第一届全国脑与认知科学学术研讨会征文通知


第一届全国脑与认知科学学术研讨会征文通知

2005年11月28日—12月2日, 中国珠海

由中国科学院生物物理研究所脑与认知科学国家重点实验室、中国生物物理学会神经生物物理与神经信息学专业委员会以及中山大学心理学系联合主办的第一届全国脑与认知科学学术研讨会定于2005年11月下旬在珠海举行。现将相关事宜通知如下:

一、会议时间:2005年11月28日—12月2日,会期:5天。

二、会议地点:珠海市中山大学武舜德国际学术交流中心

三、大会组织委员会:

  主席:陈霖, 副主席:赫荣乔,秘书:李兵
  当地主席:颜光美
  委员:(拼音排序)
  陈楚侨  陈晶  傅小兰  高定国
  高明  刘力  魏舜仪  吴梅英
  张侃  周专  卓彦 

四、大会程序委员会:

  主席:李朝义,副主席:傅小兰
  委员:(拼音排序)
  陈霖  陈惟昌  董奇  范明
  郭爱克  韩世辉  赫荣乔  李葆明
  罗跃嘉  马原野  寿天德  谭铁牛
  王书荣  杨玉芳  叶朝晖  周诚
  周江宁 

五、会议主题:

  1.感知觉信息加工
  2.脑的高级功能
  3. 神经发育与功能衰退
  4. 情绪、心理健康与认知障碍
  5. 神经信息学及动态

六、大会特邀报告:

蒲慕明教授(中国科学院上海神经科学研究所)
“Modification of Developing Neural Circuits by Sensory Experience”

王志珍院士(中国科学院生物物理研究所) 
“巯基蛋白质氧化还原酶的分子伴侣活性和二聚化作用”

韩济生院士(北京大学医学院)
“Acupoint nerve stimulation for the treatment of heroine addiction: a fMRI study”

郭爱克院士(中国科学院上海神经科学研究所/生物物理研究所)
“果蝇的两难抉择和跨模态的记忆协同”

陈霖院士(中国科学院生物物理研究所/中国科学院研究生院)
“知觉组织 - 把颠倒的特征捆绑问题再颠倒回来”

赵继宗教授(北京天坛医院)
“微创神经外科学的现状和未来”

七、征文格式:
  论文摘要为中文,摘要包括题目、作者姓名、工作单位、邮编、email地址、正文、图表及参考文献,篇幅为一个A4纸(210 mm x 297 mm) 页面,正文首行段前12磅,正文段前、段后各3磅,两端对齐,1.0倍行距。上2.5cm,下2.0cm, 左、右各2.5cm。标题为4号黑体,作者姓名、单位、邮编及地址用5号宋体,正文用小四号宋体。为了减少打印错误,请将摘要用Word文件格式编排,并注明珠海会议,通过电子邮件附件形式发送至下列e-mail地址:
  中国科学院生物物理研究所 魏舜仪
  北京市朝阳区大屯路15号(邮编 100101)
  电话:(010)64889894 
  传真:(010)64889892
  电子信箱:wsy@moon.ibp.ac.cn
  会议论文摘要集将以"生物物理学报"增刊形式刊出。

  八、会议注册费
        2005年10月20日前  2005年请10月20日后
  正式代表*  ¥1000        ¥1100
  学生#     ¥700     ¥800
  陪同    ¥700 ¥700

九、会议时间、地点及食宿安排

会议时间:2005年11月28日—12月2日

1.珠海中山大学武舜德国际学术交流中心

地 址:珠海市唐家湾港湾大道(中山大学图书馆对面)
电 话:756-3619898

2.住宿安排:

1)正式代表:珠海市中山大学武舜德国际学术交流中心:双人标间:240元/间/天(含双早), 120元/床/天(含早)。
2)学生:珠海市中山大学校内招待所*:双人标间:100元/间/天, 50元/床/天。
*:中山大学校内招待所距离武舜德国际学术交流中心步行10-15分钟。 

3. 1)为了确保您预订的房间, 请按时填写注册表中的宾馆预订,并于2005年10月20日前寄达组委会秘书处,过期我们将不能保证您的住宿。
2)上述房间均为双人标准间,代表在填写注册表时,请选择单独住或与人合住; 如与他人合住,请提供合住者姓名,以便于组委会安排。此外,选择的合住者应与您所住的夜数相同,否则出现的自然单间的费用将由您个人全部承担。

4. 会议用餐: 
  
组委会将为与会代表统一安排用餐,用餐的具体时间另行通知。早餐:在所住宾馆用餐。午餐、晚餐:全体与会代表在武舜德国际学术交流中心用餐。与会代表将在注册时领取餐券,凭券用餐,不吃不退。
随会家属收费:700元(含招待会、宴会、会议期间餐费)

十、重要时间:

1)论文摘要截止日期: 2005年9月20日
2) 会前注册: 2005年10月20日
3)发论文接受函(电子邮件):2005年10月15日 

十一、注册费付款方式(请通过电汇或邮政汇款)

电汇帐号:
中国科学院生物物理研究所(请务必注明汇款人姓名及珠海会议注册费)
0200006209088116933
北京工商行东升分理处 

邮政汇款:(务必在附言处注明以下简称:珠海会议注册费)

北京市朝阳区大屯路15号(邮编 100101)
中国科学院脑与认知科学国家重点实验室 吴梅英女士(收)
电话:010-64888778

十二、会议联系人:

1) 会议摘要:
魏舜仪:100101,北京朝阳区大屯路15号中科院生物物理所
电话:+86-10-64889894,Fax: +86-10-64889892
Email: wsy@moon.ibp.ac.cn

2)会议注册:
吴梅英:100101,北京大屯路15号中科院生物物理所
电 话:+86-10-64888778, 传真: +86-10-64853625 
Email: lvip@sun5.ibp.ac.cn

第一届全国脑与认知科学学术研讨会组委会
二○○五年七月二十五日

发布于10月25日 19:09 | 评论数(0) 阅读数(1065) | 我的文章

MIT OpenCourseWare

MIT OpenCourseWare

::URL::http://ocw.mit.edu/OcwWeb/Global/all-courses.htm

Brain and Cognitive Sciences
9.00P Introduction to Psychology, Fall 2001 
9.00W Introduction to Psychology, Fall 2002 
9.01 Introduction to Neuroscience, Fall 2004 
9.01 Neuroscience and Behavior, Fall 2001 
9.011 The Brain and Cognitive Sciences I, Fall 2002 
9.012 The Brain and Cognitive Sciences II, Spring 2002 
9.013J Cellular and Molecular Neurobiology: The Brain and Cognitive Sciences III, Spring 2003 
9.02 Brain Laboratory, Spring 2002 
9.03 Neural Basis of Learning and Memory, Fall 2001 
9.036 The Visual System, Spring 2005 NEW 
9.04 Neural Basis of Vision and Audtion, Fall 2004 NEW 
9.05 Neural Basis of Movement, Spring 2003 
9.07 Statistical Methods in Brain and Cognitive Science, Spring 2004 NEW 
9.081 Human Memory and Learning, Fall 2002 
9.09J Cellular Neurobiology, Spring 2002 
9.09J Cellular Neurobiology, Spring 2005 NEW 
9.10 Cognitive Neuroscience, Spring 2002 
9.10 Cognitive Neuroscience, Spring 2004 NEW 
9.100 Cognitive Neuroscience, Spring 2004 NEW 
9.110J Neurology, Neuropsychology, and Neurobiology of Aging, Spring 2003 
9.14 Structure & Development of the Mammalian Brain, Spring 2002 
9.15 Biochemistry and Pharmacology of Synaptic Transmission, Fall 2003 NEW 
9.150 Biochemistry and Pharmacology of Synaptic Transmission, Fall 2003 NEW 
9.16 Cellular Neurophysiology, Spring 2002 
9.18 Developmental Neurobiology, Spring 2003 
9.19J Cognitive & Behavioral Genetics, Spring 2001 
9.20 Animal Behavior, Fall 2001 
9.201 Advanced Animal Behavior, Spring 2000 
9.250 Evolutionary Psychology, Spring 1999 
9.29J Introduction to Computational Neuroscience, Spring 2002 
9.301J Neural Plasticity in Learning and Development, Spring 2002 
9.322J Genetic Neurobiology, Fall 2002 
9.35 Sensation and Perception, Spring 2004 
9.357 Special Topics in Vision Science, Fall 2001 
9.373 Somatosensory and Motor Systems, Spring 2002 
9.402 Language and Thought, Fall 2002 
9.51 Affective Priming at Short and Extremely Short Exposures, Spring 2003 
9.520 Statistical Learning Theory and Applications, Spring 2003 
9.520-A Networks for Learning: Regression and Classification, Spring 2001 
9.52-A Investigating the Neural Substrates of Remote Memory using fMRI, Spring 2003 
9.52-B Topics in Brain and Cognitive Sciences Human Ethology, Spring 2001 
9.52-C Computational Cognitive Science, Spring 2003 
9.530 Cellular and Molecular Computation, Spring 2000 
9.531J Systems Biology, Fall 2004 
9.56J Abnormal Language, Fall 2004 
9.57J Language Acquisition, Fall 2001 
9.591J Language Processing, Fall 2004 NEW 
9.591J Language Processing, Fall 2002 
9.59J Psycholinguistics, Spring 2005 NEW 
9.59J Psycholinguistics, Fall 2002 
9.601J Language Acquisition I, Spring 2002 
9.611J Natural Language and the Computer Representation of Knowledge, Spring 2003 
9.63 Laboratory in Cognitive Science, Fall 2002 
9.641J Introduction to Neural Networks, Fall 2002 
9.65 Cognitive Processes, Spring 2004 
9.67 Object and Face Recognition, Spring 2001 
9.68 Affect: Biological, Psychological, and Social Aspects of "Feelings', Spring 2002 
9.69 Foundations of Cognition, Spring 2003 
9.70 Social Psychology, Spring 2002 
9.71 Functional MRI of High-Level Vision, Fall 2002 
9.74 Foundations of Human Memory and Learning, Spring 2002 
9.75J Psychology of Gender, Spring 2003 
9.911 Reasonable Conduct in Science, January (IAP) 2002 
9.912 Special Topics in Brain and Cognitive Sciences, Fall 2001 
9.913-A Intensive Neuroanatomy, January (IAP) 2002 
9.913-C Pattern Recognition for Machine Vision, Spring 2002 
9.916 Modularity, Domain-specificity, and the Organization of Knowledge, Fall 2001 
9.916-A Probability and Causality in Human Cognition, Spring 2003 
9.93 Cognitive Neuroscience of Remembering: Creating and Controlling Memory, January (IAP) 2002 
9.95-A Research Topics in Neuroscience, January (IAP) 2003 
9.96 Experimental Methods of Adjustable Tetrode Array Neurophysiology, January (IAP) 2001 
9.97 Introduction to Neuroanatomy, January (IAP) 2003 
9.98 Language and Mind, January (IAP) 2003 


» MIT OpenCourseWare » Electrical Engineering and Computer Science » Acoustics of Speech and Hearing, Fall 2004 

::URL::http://ocw.mit.edu/OcwWeb/Electrical-Engineering-and-Computer-Science/6-551JFall-2004/LectureNotes/index.htm

Lecture Notes
L = Lectures

ses # TOPICS 
L1 Sound Measurement: Amplitude, Frequency and Phase of Simple and Complex Sounds (rms vs peak, FFT and Spectrum, Relationship between Time Waveform, FFT and Impulse Response), Lumped Elements and Waves (PDF) 
L2 Sound Propagation in Space 1: Plane Waves, Characteristic Impedance, Traveling Waves, Trading of Time and Space (PDF) 
L3 Sound Propagation in Space 2: Spherical Waves, Multiple Sources (PDF) 
L4 Diffraction of Sound, Localization Cues (PDF - 1.2 MB) 
L5 Psychoacoustics 1: Localization and Binaural Hearing 
L6 Psychoacoustics 2: Thresholds and Discrimination 
L7 Circuits 1: Lumped Elements (PDF) 
L8 Circuits 2: Combinations of Elements (PDF) 
L9 Circuits 3: Equivalent Circuits (PDF) 
L10 Circuits 4: The Loudspeaker (PDF) 
L11 Circuits 5: Microphones and Middle Ears (PDF) 
L12 The Normal and Diseased Middle Ear (PDF - 1.6 MB) 
L13 Psychoacoustics 3: Masking and Frequency Selectivity 
L14 Psychoacoustics 4: Frequency Selectivity and Hearing Loss 
L15 Tubes 1: Dimensional Equations, Natural Frequencies (PDF) 
L16 Tubes 2: Perturbation Theory (PDF) 
L17 Tubes 3: Non-Uniformities and Losses (PDF) 
L18 Cochlear Mechanics 1: Hair Cells 
L19 Cochlear Mechanics 2: The Passive Cochlea 
L20 Speech Production 1: Vowels (PDF - 2.7 MB) 
L21 Cochlear Mechanics 3: The Active Cochlea 
L22 Speech Production 2: Fricative Sources and Consonants (PDF - 1.3 MB) 
L23 Speech Sound Production 3: More Consonants (PDF) 
L24 Speech Perception (PDF) 
L25 Psychoacoustics and Physiology: Gold 1948 




» MIT OpenCourseWare » Electrical Engineering and Computer Science » Speech Communication, Spring 2004 
6.541J / 24.968J / HST.710J Speech Communication, Spring 2004

::URL::http://ocw.mit.edu/OcwWeb/Electrical-Engineering-and-Computer-Science/6-541JSpring2004/CourseHome/index.htm

 
Cover of 6.541J textbook: Stevens, Kenneth. Acoustic Phonetics. Cambridge, MA: MIT Press, 1999. ISBN: 0-262-19404-X. (Image courtesy of MIT Press.) 
Highlights of this Course
This course site features assignments with solutions, along with lecture handouts featuring figures from Prof. Kenneth Stevens' book, Acoustic Phonetics, published by MIT Press in 1999. 
Course Description
6.541J surveys the structural properties of natural languages, with special emphasis on the sound pattern. Topics covered include: representation of the lexicon; physiology of speech production; articulatory phonetics; acoustical theory of speech production; acoustical and articulatory descriptions of phonetic features and of prosodic aspects of speech; perception of speech; models of lexical access and of speech production and planning; and applications to recognition and generation of speech by machine, and to the study of speech disorders. 
  Staff
Instructor:
Prof. Kenneth Stevens 
Course Meeting Times
Lectures:
Two sessions / week
1.5 hours / session 
Labs:
Three sessions total
2 hours / session

Level
Graduate 
Feedback
Send feedback about OCW or this course.

发布于10月25日 19:06 | 评论数(0) 阅读数(950) | 我的文章

The Brain by Bob Murray, PhD

The Brain

Written and researched by Bob Murray, PhD

Latest News | Back Issues | Get monthly updates: Subscribe Now

1 | 2 | 3 | 4 | 5 | 6   Next

Love is in the Brain

Aug 5, 2005

Have all those songs got it wrong? And all those psychologists from Freud to the present? Is it a love drive not a sex drive after all?

A team led by a neuroscientist, an anthropologist and a social psychologist found love-related neurophysiological systems (drives to you and me) inside a magnetic resonance imaging machine.

They detected quantifiable love responses in the brains of 17 young men and women who each described themselves as being newly and madly in love.

The multidisciplinary team found that early, intense romantic love may have more to do with motivation, reward and "drive" aspects of human behavior than with the emotions or sex drive. Brain systems were activated that humans share with other mammals. So the researchers think "early-stage romantic love is possibly a developed form of a mammalian drive to pursue preferred mates, and that it has an important influence on social behaviors that have reproductive and genetic consequences."

"It's a stark reminder that the mind truly is in the brain," noted Lucy L. Brown of the Albert Einstein College of Medicine. "We humans are built to experience magical feelings like love, but our findings don't diminish the magic in any way. In fact, for some, it enhances the experience. Our research also helps to explain why a person in love feels 'driven' to win their beloved, amidst a whole constellation of other feelings."

The study, entitled "Reward, motivation and emotion systems associated with early-stage intense romantic love," is published in the July issue of the Journal of Neurophysiology, published by the American Physiological Society.

"Most of the participants in our study clearly showed emotional responses," noted Arthur Aron of the State University of New York-Stony Brook, "but we found no consistent emotional pattern. Instead, all of our subjects showed activity in reward and motivation regions. To emotion researchers like me, this is pretty exciting because it's the first physiological data to confirm a connection between romantic love and motivation networks in the brain.

"As it turns out, romantic love is probably best characterized as a motivation or goal-oriented state that leads to various specific emotions, such as euphoria or anxiety," Aron noted. "With this view, it becomes clearer why the lover expresses such an imperative to pursue his or her beloved and protect the relationship." Aron added: "Our participants who measured very high on a self report questionnaire of romantic love also showed strong activity in a particular brain region."

Aron also noted that the research answered the "historic question of whether love and sex are the same, or different, or whether romantic passion is just warmed over sexual arousal." He said, "Our findings show that the brain areas activated when someone looks at a photo of their beloved only partially overlap with the brain regions associated with sexual arousal. Sex and romantic love involve quite different brain systems."

Aron reported that, using functional magnetic resonance imaging (fMRI) and other measurements, he and his colleagues found support for their two major predictions: (1) early stage, intense romantic love is associated with subcortical reward regions rich with dopamine; and (2) romantic love engages brain systems associated with motivation to acquire a reward.

Brown explains some of these findings, commenting that "when our participants looked at a photo of his/her beloved, specific activation occurred in the right ventral tegmental area (VTA) and dorsal caudate body. These regions were significant compared to two control conditions, providing strong evidence that these brain areas, which are associated with the motivation to win rewards, are central to the experience of being in love."

Another important discovery, Brown said, was that "to our surprise, the activation regions associated with intense romantic love were mostly on the right side of the brain, while the activation regions associated with facial attractiveness were mostly on the left.

"We didn't predict such a striking lateralization," Brown reported. "It is well known that speech is largely a left-sided cortical function. But our data indicate that lateralization also occurs in lower parts of the brain. Moreover, different kinds of rewards (in this case, the "rush" of romantic love, compared with the pleasing experience of looking at a pretty or handsome face) is also lateralized. These results give us a lot to think about how the normal human brain learns and remembers and functions in general," Brown added.

Another breakthrough, Brown noted, was that "we found several brain areas where the strength of neural activity changed with the length of the romance. Everyone knows that relationships are dynamic over time, but we are beginning to track what happens in the brain as a love relationship matures."

Helen E. Fisher, a research anthropologist at Rutgers University, New Jersey, noted that not only did the brain change as romantic love endured, but that some of these changes were in regions associated with pair-bonding in prairie voles. The fMRI images showed more activity in the ventral pallidum portion of the basal ganglia in people with longer romantic relationships. It's in this region where receptors for the hormone vasopressin are critical for vole pair-bonding, or attachment.

So that's why Alicia and I are together, and in love, after 22 years! Who'd have thunk it!

"Humans have evolved three distinct but interrelated brain systems for mating and reproduction - the sex drive, romantic love, and attachment to a long term partner," Fisher said, "and our results suggest how feelings of romantic love might change into feelings of attachment. Our results support what people have always assumed--that romantic love is one of the most powerful of all human experiences. It is definitely more powerful than the sex drive."

Read more in the Journal of Neurophysiology

Top of page

Scientists Amazed At the Power of a Single Cell

Aug 5, 2005

World travelers instantly identify the architectural sails of the Sydney Opera House from most any angle. Movie aficionados immediately recognize Oscar-winner Halle Berry beneath her "Catwoman" costume or in an artist's caricature.

But how does the human brain translate varied and even abstract visual images into a single instantly and consistently recognizable concept? A research team led by neuroscientists at UCLA and California Institute of Technology shows the process begins with a single brain cell.

Reporting in the June 23 edition of journal Nature, the researchers find that individual neurons are able to recognize people, landmarks and objects--even letter, strings of names. The findings suggest a consistent, sparse and explicit code that may play a role in transforming complex visual representations into long-term and more abstract memories.

"This new understanding of individual neurons as 'thinking cells' is an important step toward cracking the brain's cognition code," said senior investigator Dr. Itzhak Fried, professor of neurosurgery at the David Geffen School of Medicine at UCLA "As our understanding grows, we one day may be able to build cognitive prostheses (like artificial limbs) to replace functions lost due to brain injury or disease, perhaps even for memory."

"Our findings fly in the face of conventional thinking about how brain cells function," adds senior investigator Christof C. Koch, professor of Cognitive and Behavioral Biology at Caltech. "Conventional wisdom views individual brain cells as simple switches or relays. In fact, we are finding that neurons are able to function more like a sophisticated computer." This study is the latest of several landmark observations made in recent years by the UCLA team, which is probing the underpinnings of the human mind at the single neuron level in humans. Two years ago they identified single cells in the human hippocampus specific to places during human navigation.

The body of work is an example of the power of neurobiological research using data drawn directly from inside a living human brain. Most neurobiological research involves animals, post-mortem tissue or imaging. In contrast, Fried and his UCLA team draw data directly from the brains of living people.

For the latest study, the research team recorded responses from the medial temporal lobe, which plays a major role in human memory and is one of the first region's affected in patients with Alzheimer's Disease. Responses by individual neurons appeared on a computer screen as spikes on a graph.

In the initial recording session, subjects viewed a large number of images of famous people, landmark buildings, animals, objects and additional images chosen after an interview. To keep the subjects focused, researchers asked them to push a computer key to indicate whether the image was a person. After determining which images prompted a significant or strong response in at least one neuron, additional sessions tested response to three to eight variations of each of those images.

Responses among the eight subjects varied with the person and stimulus. For example, a single neuron in the left posterior hippocampus of one subject responded to 30 out of 87 images, firing in response to all pictures of actress Jennifer Aniston, but not, or only very weakly, to other famous and non-famous faces, landmarks, animals or objects. The neuron also did not respond to pictures of Jennifer Aniston together with actor Brad Pitt.

In another instance, pictures of actress Halle Berry activated a neuron in the right anterior hippocampus of a different patient, as did a caricature of the actress, images of her in the lead role of the film "Catwoman," and a letter sequence spelling her name.

In a third subject, a neural unit in the left anterior hippocampus responded to pictures of the landmark Sydney Opera House and Baha'i Temple, and also to the letter string "Sydney Opera," but not to other letter strings, such as "Eiffel Tower."

Read more in Nature

Top of page

Brainy Birds

Aug 5, 2005

A Brandeis University researcher has shown that an African grey parrot with a walnut-sized brain understands a numerical concept akin to zero--an abstract notion that humans don't typically understand until age three or four, and that can significantly challenge learning-disabled children.

Strikingly, Alex, the 28-year-old parrot who lives in a Brandeis lab run by comparative psychologist and cognitive scientist Dr. Irene Pepperberg, spontaneously and correctly used the label "none" during a testing session of his counting skills to describe an absence of a numerical quantity on a tray. This discovery prompted a series of trials in which Alex consistently demonstrated the ability to identify zero quantity by saying the label "none."

Dr. Pepperberg's research findings, published in the current issue of The Journal of Comparative Psychology, add to a growing body of scientific evidence that the avian brain, though physically and organizationally somewhat different from the mammalian cortex, is capable of higher cognitive processing than previously thought. Chimpanzees and possibly squirrel monkeys show some understanding of the concept of zero, but Alex is the first bird to demonstrate an understanding of the absence of a numerical set, Dr. Pepperberg noted.

"It is doubtful that Alex's achievement, or those of some other animals such as chimps, can be completely trained; rather, it seems likely that these skills are based on simpler cognitive abilities they need for survival, such as recognition of more versus less," explained Dr. Pepperberg.

Alex had previously used the label "none" to describe an absence of similarity or difference between two objects, but he had never been taught the concept of zero quantity. "Alex has a zero-like concept; it's not identical to ours but he repeatedly showed us that he understands an absence of quantity," said Dr. Pepperberg.

Historically, the use of "zero" to label a null set has not always been obvious even in human cultures, which in many cases lacked a formal term for zero as recently as the late Middle Ages. The value of number research lies mainly in its ability to help determine the extent of animal cognition and animals' potential for more complex capacities. To that end, Dr. Pepperberg's studies on the avian brain are continuing with research into Alex's ability to count, as well as add and subtract small quantities.

Yet significantly, Dr. Pepperberg's research, which uses a training method called the model-rival technique, also holds promise for teaching autistic and other learning-disabled children who have difficulty learning language, numerical concepts and even empathy.

The model rival technique involves two trainers, one to give instructions, and one to model correct and incorrect responses and to act as the student's rival for the trainer's attention; the model and trainer also exchange roles so that the student sees that the process is fully interactive. The student, in this case, a middle-aged parrot, tries to reproduce the correct behavior. So far, results using this learning technique with small groups of autistic children, taught by Diane Sherman, PhD, in Monterey, CA, have been very promising, said Dr. Pepperberg.

"This kind of research is changing the way we think about birds and intelligence, but it also helps us break down barriers to learning in humans--and the importance of such strides cannot be underestimated," said Dr. Pepperberg.

Read more in the Journal of Comparative Psychology

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Exercise Slows Onset of Alzheimer's

June 6, 2005

Recently exercise has been proven to be better than antidepressants for depression and better than Ritalin for ADD/ADHD. Now it would seem that exercise has the same beneficial effect on those suffering from Alzheimer's Disease.

Researchers have found that physical activity appears to inhibit Alzheimer's-like brain changes in mice, slowing the development of a key feature of the disease. Their research demonstrated that long-term physical activity enhanced the learning ability of mice and decreased the level of plaque-forming beta-amyloid protein fragments--a hallmark characteristic of Alzheimer's disease (AD)--in their brains.

A number of population-based studies suggest that lifestyle interventions may help to slow the onset and progression of AD. Because of these studies, scientists are seeking to find out if and how physical or mental activity might delay the onset and progression of the disease. In this study, scientists have now shown in an animal model system that one simple behavioral intervention--exercise--could delay, or even prevent, development of AD-like syptoms by decreasing beta-amyloid levels.

Results of this study, conducted by Paul A Adlard, PhD, Carl W Cotman, PhD, and colleagues at the University of California, Irvine, are published in the April 27, 2005, issue of The Journal of Neuroscience.

To directly test the possibility that exercise (in the form of voluntary running) may reduce the cognitive decline and brain changes that characterize AD, the study used genetically engineered animals rather than normal mice. These mice begin to develop AD-like amyloid plaques at around 3 months of age. Initially, young mice (6 weeks or 1 month of age) were placed in cages with or without running wheels for periods of either 1 month or 5 months, respectively.

Mice with access to running wheels had the opportunity to exercise any time, while those without the wheels were classified as "sedentary." On 6 consecutive days after the exercise phase, the researchers placed each mouse in a Morris water maze to examine how fast it could learn the location of a hidden platform and how long it retained this information. (This water maze task involves a small pool of water with a submerged platform that the mouse must learn how to find.)

The animals that exercised learned the task faster. Thus, the mice that used the running wheels for 5 months took less time than the sedentary animals to find the escape platform. The exercised mice acquired maximal performance after only 2 days on the task, while it took more than 4 days for the sedentary mice to reach that same level of performance. This suggests that exercise may help to offset learning/cognitive deficits present in AD patients.

Next, the investigators examined tissues from the brains of mice that had exercised for 5 months. Compared to the sedentary animals, mice that had exercised for 5 months on the running wheels had significantly (50%) fewer plaques and fewer beta-amyloid fragments (peptides) in the cerebral cortex and hippocampus, that characterize AD. Additional studies, of exercised animals at 10 weeks old, showed that the mechanism underlying this difference began within the first month of exercise.

"These results suggest that exercise--a simple behavioral strategy--in these mice may bring about a change in the way that amyloid precursor protein is metabolized," says D. Stephen Snyder, Ph.D., director of the etiology of Alzheimer's program in the NIA's Neuroscience and Neuropsychology of Aging Program. "From other research, it is known that in the aging human brain, deposits of beta-amyloid normally increase. This study tells us that development of those deposits can be reduced and possibly eliminated through exercise"

Mental exercise also helps!

These findings follow another recent report of a link between an enriched environment and Alzheimer's-like brain changes. That study, published by Orly Lazarov, PhD, and colleagues in the March 11, 2005, issue of the journal Cell, found that beta-amyloid levels decreased in the brains of another kind of genetically modified mice when they were housed in groups and in environments that were enriched with running wheels, colored tunnels, and toys.

"Both of these studies are exciting because they offer insight into one of the pathways through which exercise and environment might promote resistance to development of cognitive changes that come with aging and AD," Snyder notes.

Read more in the Journal of Neuroscience

Read more in Cell

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How Babies Learn Language

April 1, 2005

Adults may feel silly when they talk to babies, but those babies will learn to speak sooner if adults talk to them like infants instead of like other adults, according to a study by Carnegie Mellon University Psychology Professor Erik Thiessen published in the March 2005 issue of the journal Infancy.

Most adults speak to infants using so-called infant-directed speech: short, simple sentences coupled with higher pitch and exaggerated intonation. Researchers have long known that babies prefer to be spoken to in this manner. But Thiessen's research has revealed that infant-directed speech also helps them learn words more quickly than normal adult speech.

In a series of experiments, he and his colleagues exposed 8-month-old infants to fluent speech made up of nonsense words. The researchers assessed whether, after listening to the fluent speech for less than two minutes, infants had been able to learn the words. The infants who were exposed to fluent speech with the exaggerated intonation contour characteristic of infant-directed speech learned to identify the words more quickly than infants who heard fluent speech spoken in a more monotone fashion.

Thiessen's study may also explain why many adults struggle to learn a second language even though they are able to use their own language effortlessly. Children, after all, learn to speak practically from scratch, and most experts believe infants are more adept than adults at language learning. "Learning a language is one of the most critical things that an infant has to do, because communication with other people is tremendously important," Thiessen said. "It makes a great deal of sense that the special way we have of talking to babies would help them learn."

Read more in Infancy

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Active Lifestyle Helps Prevent Alzheimer's

April 1, 2005

Researchers at the University of Chicago working with mice found that an enriched environment--in this case more chances to exercise, explore and interact with others--can dramatically reduce the biological hallmarks of Alzheimer's disease in animals genetically predisposed to the disorder.

In the journal Cell, the researchers show that mice raised in a deluxe setting--large cages filled with running wheels, colored tunnels and multiple toys--had much less of the beta-amyloid peptides that are characteristic of Alzheimer's disease deposited in their brains and far lower levels of these damaging peptides in their blood than genetically similar mice raised in a standard environment.

Mice from enriched settings also had more of an enzyme that breaks down amyloid as well as increased activity of several genes involved in learning and memory, brain cell survival and the growth of new blood vessels. "We have plenty of epidemiological evidence connecting activity, exercise and education with later onset of Alzheimer's, but it has never been clear which came first," said study-author Sangram Sisodia, PhD, professor of neurobiology, pharmacology and physiology at the University of Chicago. "Did the active lifestyle delay disease, or was there something inherent in a disease-resistant brain that led to a mentally and physically active lifestyle?"

"This is the first demonstration," he said, ""in a genetically clean, carefully controlled animal model showing that an enhanced environment can have such a tremendously beneficial impact, protecting the brain from the pathological hallmarks of this insidious disease."

These findings support a "potentially causal inverse relationship between a more engaging, enriched life and AD progression," the researchers note. They also provide "clear initial directions for exploring the role of the environment and the molecular pathways perturbed in AD and other neurodegenerative disorders."

Sisodia, and colleagues studied mice carrying two distinct genes (amyloid precursor protein and presenilin-1) that predispose the animals to develop Alzheimer's early in life. At one month of age, nine of these mice were placed in the enriched environment and seven in standard housing. After five months, the researchers began to search for the pathological signs of AD in the mice's brains.

They found that mice from the enriched environment had a dramatic reduction of amyloid deposits in their brains, including less than half the volume of amyloid deposits in the hippocampus and cortex, regions involved in memory and reasoning.

The researchers also looked for genes that were activated at different levels in brains of mice from enriched versus standard housing. They identified 41 such genes, many of them already known to protect nerve cells. One of them was the gene for an enzyme that degrades beta-amyloid called neprilysin, which was at significantly higher levels in mice from the enhanced setting.

The researchers also noted one "personality" difference among the mice in the enriched environment that influenced amyloid levels. Some of these mice were extremely active, frequently exploring their cages or running on the wheel. Others, the couch-potato mice, had the same opportunities for exercise but chose much less activity.

The most active mice had the least beta-amyloid. Less active mice from the enriched environment had more and those from the standard housing, who got the least exercise, had the most.

A lot of the process involves simple plumbing, Sisodia suspects, delivering blood to the brain and carrying harmful substances away. "It may be all about blood flow," he suggested. Exercise and mental activity can stimulate growth of new vessels while they help keep existing vessels in the brain open and functional, just like in the heart.

The take home message for humans, he said, is use it or lose it. ""Activity helps, physical activity helps and mental activity helps," he said, "and the earlier you begin the better, a troubling notion in an increasingly inactive society. This is prevention, not therapy."

About 4.5 million people in the United States have Alzheimer's disease, including about five percent of those aged 65 to 74. Risk increases with age.

Read more in Cell.

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Ageing Improves Vision

March 1, 2005

It's not all down hill from here, folks! The long-held belief that older people perform slower and worse than younger people has been proven wrong. In a study published in Neuron, psychologists from McMaster University discovered that the ageing process actually improves certain abilities: Older people appear to be better and faster at grasping the big picture than their younger counterparts. That's, after all, what the tribal council of elders was supposed to do. They knew a thing or two those hunter-gatherers!

"Going into the study, we knew that ageing changes the way people see the world," says Allison Sekuler, one of the senior authors. "But these results are an unusual twist on the standard 'ageing makes you worse' story, and they provide clear insight into what is changing in the ageing brain."

Using computer-generated stimuli, the researchers monitored how much time subjects needed to process information about the direction in which a set of bars moved. When the bars were small, or when the bars were low in contrast (light gray vs. dark gray), younger subjects took less time to see the direction of motion. But when the bars were large, and high in contrast (black vs. white), older subjects outperformed the younger subjects.

"The results are exciting not only because they show an odd case in which older people have better vision than younger people, but also because it may tell us something about how ageing affects the way signals are processed in the brain," says Patrick Bennett, the other senior author.

The results suggest that as we age, the ability of one brain cell to inhibit another is reduced. That sort of inhibition helps young people find an object hidden among clutter, but it can make it hard to tune into the clutter itself. When the young brain sees big, high-contrast bars, it effectively tunes out because there is no object hidden in the bars. But older brains do not inhibit information in the same way, so they do not tune out the bars, and they can actually perform the task better.

"As we get older, it becomes harder to concentrate on one thing and ignore everything else," says Bennett. "It takes more effort to tune out distractions. We've seen it in cognition and speech studies, and now we see it in vision. Although we don't know if those are all linked, we think the visual effect is due to changes in the effectiveness of inhibitory neurotransmitters in the brain." Neurotransmitters (as all frequent readers of our site know by now) are chemical substances that can modify the way in which brain cells talk to one another. Some neurotransmitters enhance brain signals, and others inhibit them.

The study suggests that one type of inhibitory neurotransmitter may not have as much effect in old brains as in young brains. However, the researchers caution that although such a change makes older people perform better on this task, the same change likely leads to increased difficulties in a much wider range of tasks. "It's critical to understand how ageing affects vision and the brain. If we can characterize what is happening to our brains as we age, we'll be in a better position to help seniors see better for longer," says Sekuler.

Read more in Neuron.

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How Babies Recognize Mother

December 6, 2004

We are born with the capacity to recognize faces, new research has found. While neurobiologists have known for some time that a particular area of the brain, called the fusiform face area (FFA), lights up with activity when we see a face--and even that the FFA is necessary for us to recognize faces--there has been controversy over what kind of processing the area is doing.

Now, researchers Galit Yovel and Nancy Kanwisher have tackled two central questions with one set of experiments: the nature of processing that occurs in the FFA and whether the FFA is "domain specific," that is, exclusively involved in face perception, or whether the area is engaged in more general spatial processing of visual features.

What they found was that the FFA extracts configural information about faces (ie sees them as a whole) rather than processing spatial information on the parts of faces. This is quite different to what researchers had previously believed. Also, their studies indicated that the FFA is exclusively involved in face recognition. So we have a part of the brain whose sole job is to recognize faces. Our mug shot filing system.

The researchers' experiments used functional magnetic resonance imaging (fMRI) of subjects as they performed recognition tasks. In the fMRI, scans harmless magnetic fields and radio signals are used to measure brain activity as subjects perform tasks.

Read more in Neuron

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Use it or Lose It: Seniors Need to Socialize to Keep Communication Skills

September 1, 2004

Senior citizens living alone and independently in apartments should interact often with others--both friends and family members--if they want to maintain their ability to communicate, a new University of Michigan study showed.

A lifestyle with organized activities seems to provide the best social opportunities for the elderly, said Deborah Keller-Cohen, a U-M professor of women's studies and linguistics.

Much is known about the association between declines in cognitive function among the elderly and the ability to communicate, but little has been explored about what role social engagement might play in that relationship. The U-M research targeted people 85 and older-the fastest growing segment of the US population, Keller-Cohen said.

The researchers examined the relationships among social engagement, cognition and communicative skills. They reviewed notebooks kept by the study's participants, who tracked the frequency, purpose and quality of interactions. The participants were tested on their ability to name objects in pictures, a common measure of language skill ability.

Individuals who experienced less cognitive decline were involved in a wider range of relationships, each of which challenges individuals to speak and listen to others on a range of topics. Thus, this diversity in interaction would seem to keep one's linguistic skills activated, she said.

When the elderly limited their contact solely to family members, they didn't fare as well as they could have with communications skills had they also interacted with others, Keller-Cohen said. Although additional research is required, this might have implications for how senior living centers structure programming and activities.

"It's possible that as individuals decline cognitively, they become less able to handle social contact and become more dependent on family members who by virtue of kin obligations, will continue to interact with them," she said.

This research, "Social Contact and Communication in People Over 85," was presented at the recent American Psychological Association conference in Hawaii and has not yet been published.

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Reading, Writing, Rithmatic, Rhythm and Role-Playing: The New Five Rs?

September 1, 2004

Just when schools all over the developed world were gutting down on their "non essential" subjects such as music and drama comes a study which confirms that these subjects maybe should be right up there with the other Rs.

The study, led by Dr E Glenn Schellenberg, of the University of Toronto, examined the effect of extra-curricular activities on the intellectual and social development of six-year-old children. A group of 144 children were recruited through an ad in a local newspaper and assigned randomly to one of four activities: keyboard lessons, voice lessons, drama lessons, or no lessons.

Two types of music lessons were offered in order to be able to generalize the results, while the groups receiving drama lessons or no lessons were considered control groups in order to test the effect of music lessons over other art lessons requiring similar skill sets and nothing at all. The activities were provided for one year.

The participating children were given IQ tests before and after the lessons. The results of this study revealed that increases in IQ from pre- to post-test were larger in the music groups than in the two others. Generally these increases occurred across IQ subtests, index scores, and academic achievement. Children in the drama group also exhibited improvements pre- to post-test, but in the area of adaptive social behavior, an area that did not change among children who received music lessons.

The study was published in the August 2004 issue of Psychological Science.

Read more in Psychological Science

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What Are Babies Thinking?

August 4, 2004

Look who's thinking! A study published in the July 22 issue of Nature shows that babies are quite thoughtful, even if they don't have the words to express their thoughts.

The research was conducted by Sue Hespos, assistant professor of psychology at Vanderbilt University, and Elizabeth Spelke, professor of psychology at Harvard University. “It's been shown in previous studies that adults actually categorize things differently based on what language they speak,” Hespos said. “So, if language is influencing adults' thought, one of our questions was, what's going on with preverbal infants? Do children think before they speak?

“Language capitalizes on a pre-existing system of 'I live in a 3-D world, I know how objects behave and interact,'” she continued. “This pre-existing ability suggests that children do think before they speak.”

Previous research has found that infants are sensitive to the acoustic variations that signal meanings in all the world's languages that adults can no longer hear, even those variations that their own language does not use and that the adults around them no longer hear. For instance, an adult native-English speaker will not hear all of the sounds of Korean and vice versa. Infants hear these subtleties but lose this awareness as their language skills develop over the first year of life.

“The languages of the world vary both in the sounds they require speakers to distinguish and in the meanings they require speakers to convey, and these differences influence what speakers of a language readily hear and think about,” Spelke said. “Our research asked how these differences arise: Does the experience of learning to speak English or Korean make you aware of the categories your language honors?”

The example they used to explore this question was differences between how different languages describe space. For example, the distinction between a tight fit versus a loose fit is marked in Korean but not in English. A cap on a pen would be a tight fit relationship, while a pen on a table would be a loose fit relationship. English does not mark this distinction in the same way, instead emphasizing the “containment” versus “support” relationship, for example: the coffee is in the mug or the mug is on the table.

Hespos and Spelke tested whether five-month-old infants from native English-speaking homes noticed whether objects fit tightly or loosely. The tests were based on infants' tendency to look at events that they find to be novel. Infants were shown an object being placed inside a container that fit either tightly or loosely until the time they looked at the object being placed inside the container decreased. They were then shown new tight and loose fit relationships. The researchers found that the babies looked at the objects longer when there was a change between tight or loose fit, illustrating that they were detecting the Korean concept.

Hespos and Spelke also conducted the experiment with adults to confirm that English-speaking adults do not spontaneously make the tight versus loose fit distinction. “Adults ignore tight fit versus loose fit and pay attention to 'in' versus 'on,'” Hespos said. “Adults were glossing over the distinction that the babies were actually detecting.”

“These findings suggest that humans possess a rich set of concepts before we learn language,” Spelke added. “Learning a particular language may lead us to favor some of these concepts over others, but the concepts already existed before we put them into words.”

Read more in Nature

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The Dopamine Reward

May 11, 2004

Researchers, using a new combination of techniques, have discovered that dopamine levels in our brains vary the most in situations where we are unsure if we are going to be rewarded, such as when we are gambling or playing the lottery.

The research results, "Dopamine Transmission in the Human Striatum during Monetary Reward Tasks," were published online April 28 in the Journal of Neuroscience.

Dopamine has long been known to play an important role in how we experience rewards from a variety of natural sources, including food, relationships and sex, as well as from drugs such as cocaine and heroin, but pinning down the precise conditions that cause its release has been difficult.

"Using a combination of techniques, we were actually able to measure release of the dopamine neurotransmitter under natural conditions using monetary reward," said David Zald, assistant professor of psychology at Vanderbilt University.

Zald believes the primary significance of the study is the possibilities it raises for future research on measuring what causes us to experience reward from a variety of sources and what happens in our brains when we are disappointed in our quest for those rewards. The research lays a foundation for a better understanding of what happens in the brain during unpredictable reward situations such as gambling, (or, for that matter forming new friendships) and offers promise for exploring the chemical foundation of problems such as gambling addiction.

Zald and his colleagues used positron emission topography (PET scanners) to view brain activity in nine human research subjects who had been injected with a chemical that binds to dopamine receptors in the brain, but is less able to bind when the brain is releasing dopamine. A decrease in binding to the receptors is associated with an increase in dopamine release, while an increase in binding indicates reduced release of dopamine. This technique allows researchers to study the strength and location of dopamine release more precisely than has previously been possible.

The team studied the subjects under three different scenarios. Under the first scenario, the subject selected one of four cards and knew a monetary reward of $1 was possible but did not know when it would occur. During the second scenario, subjects knew they would receive a reward with every fourth card they selected. Under the third scenario, subjects chose cards but did not receive or expect any rewards.

Zald and his team found that over the course of the experiment, dopamine transmission increased more in one part of the brain in the unpredictable first scenario, while showing decreases in neighboring regions. In contrast, the receipt of a reward under the predictable second scenario did not result in either significant increases or decreases in dopamine transmission.

"It's probably not just the receipt of money, but the conditions under which it occurs which makes a difference," Zald explained.

The increase and suppression were localized to specific, separate regions of the brain, illustrating that variable reward scenarios, like gambling, have a complex effect on the brain. "The most interesting thing we found is that there were areas that showed increased dopamine release during the unpredictable condition, and there were also other areas showing decreased dopamine release, so other than just dopamine as reward, there is a more complicated action occurring."

For us the interesting thing here is that the research ties in with our view of the brain as very much a hunter-gatherer instrument. The situation of gambling with an unpredictable reward is exactly like "primitive" hunting on the African savannah (I've witnessed this--BM). The danger of being attacked by a predator is the gamble, the antelope is the reward. The same process occurs when meeting new people--the danger of rejection or harm is the gamble, their meeting our needs is the reward.

in Journal of Neuroscience

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New Insights on Sex Drive

April 3, 2004

For almost a decade, researchers at Pfizer struggled to show that Viagra could enhance sexual function in women. Last month, they gave up.

Tests on thousands of women made it clear that the pill, thought able to stir arousal, did not always evoke sexual desire. Viagra's failure underscored the obvious: When it comes to sexuality, men and women to some extent are differently tuned. For men, arousal and desire are often intertwined, while for women, the two are frequently distinct.

Scientists have recently begun to map out this difference in the brain. Male arousal, studies find, is strongly visual, and when men engage in sexual activity or even anticipate it, brain structures once thought to have little connection to sex spring into action. The same brain regions, however, remain relatively quiet when women are aroused.

At the core of the sexual divide, some researchers say, is the amygdala, walnut shaped part of the limbic system, the brain's seat of emotions.

In one recent study, a team of researchers at Emory University had 28 men and women look at erotic photographs while an MRI took snapshots of their brains. A pattern immediately emerged: There was a frenzy of brain activity, particularly in the amygdalae of men. Yet the two groups reported equal arousal most of the time.

"This definitely emphasizes that up until recently the amygdala has been overlooked," said Stephan Hamann, a professor of psychology and the lead author of the study, which was published in Nature Neuroscience.

In another study published last year, researchers in the Netherlands recorded brain activity in men as their female partners brought them to orgasm. The amygdala showed decreased activity during climax. Other studies have suggested that a larger amygdala may lead to a more robust sex drive.

Hamann said the amygdala is known to have intricate connections to primates' visual systems. One reason for the response to visual stimuli in men, he said, could be cultural. Men tend to be inundated with sexual imagery and, possibly, are more likely to seek it out.

in Nature Neuroscience

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Clever Pretty Polly!

February 18, 2004

Alicia and I are constantly amazed by the way that we humans think we are so unique. We're not. In every single way in which we have tried to differentiate ourselves we have found that there are other creatures with the same attributes as us.

Just to take a few: It used to be thought that we were the only tool-makers. Now we know that bonobos, chimpanzees and crows (to name just a few) make and use tools.

Our psychologists, philosophers and theologians said that what separated us from other members of the animal kingdom was consciousness--the sense of knowing who we were and where we existed in time and space. Well, not so. Neuroscientists discovered a few years ago that we share this with chickens (and virtually all other forms of sentient life).

"Mathematics!" Yelled those who wanted to retain our specialty. Sorry, guys, try again. Other species can count.

"It's our use of language," the humanophiles cried. Not so. Chimpanzees can be taught to use human language and to construct sentences. And not only chimps. The finding of a parrot with an almost unparalleled power to communicate with people has brought scientists up short.

The bird, a captive African grey called N'kisi, has a vocabulary of 950 words, and shows signs of a sense of humor. He invents his own words and phrases if he is confronted with novel ideas with which his existing repertoire cannot cope--just as a human child would do.

N'kisi's remarkable abilities, which are said to include telepathy, is believed to be one of the most advanced users of human language in the animal world. About 100 words are needed for half of all reading in English, so if N'kisi could read he would be able to cope with a wide range of material.

The parrot uses words in context, with past, present and future tenses, and is often inventive. One N'kisi-ism was "flied" for "flew", and another "pretty smell medicine" to describe the aromatherapy oils used by his owner, an artist based in New York.

When he first met Dr Jane Goodall, the renowned chimpanzee expert, after seeing her in a picture with apes, N'kisi said: "Got a chimp?"

He appears to fancy himself as a humourist. When another parrot hung upside down from its perch, he commented: "You got to put this bird on the camera."

Dr Goodall says N'kisi's verbal fireworks are an "outstanding example of interspecies communication".

In an experiment, the bird and his owner were put in separate rooms and filmed as the artist opened random envelopes containing picture cards. Analysis showed the parrot had used appropriate keywords three times more often than would be likely by chance. This was despite the researchers discounting responses like "What ya doing on the phone?" when N'kisi saw a card of a man with a telephone, and "Can I give you a hug?" with one of a couple embracing.

Professor Donald Broom, of the University of Cambridge's School of Veterinary Medicine, said: "The more we look at the cognitive abilities of animals, the more advanced they appear, and the biggest leap of all has been with parrots."

in Science

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It's Chemistry

February 18, 2004

"I feel my synaptic receptors taking up oxytocin whenever I'm around you. Will you marry me?" There's something rather unromantic about this proposal.

However recent research has highlighted that love is very much a matter of brain chemistry. According to neuroscientist Professor Gareth Leng of Edinburgh University in a recent lecture called "How Does the Brain Fall in Love" oxytocin is the neuroglue that helps bond a mother and her baby. It is also released during childbirth and orgasm. He said it acts like a "master switch" in the brain, opening up new patterns of interaction between nerve cells.

He also claims that people who have fewer of the special brain receptors needed to take up the oxytocin may have difficulties in making successful permanent bonds with their partners.

Research has found that the hormone, which is released into the brain in large amounts during labour and during sexual activity, is an important trigger of maternal behavior in animals. Its crucial role in sexual bonding has been observed by scientists studying the prairie vole.

The prairie vole mates for life and this life-long bond is established over the 48 hours of intense mating activity that is its first experience of sex. According to Professor Leng: "During this time, large amounts of oxytocin are released within the brain. Prairie voles have oxytocin receptors in different parts of their brains, and scientists have found that blocking these receptors prevents the formation of pair-bonding in females. How a single, albeit prolonged, exposure to oxytocin can produce such profound and prolonged changes in behavior is not known, but we are trying to find answers."

Reported in BBC News Online

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Updated IQ Tests Can Wreak Havoc

December 16, 2003

I always thought that IQ tests were useless and really said very little about the individual. But now researchers from Cornell University have come up with findings that show that they can be positively deadly.

They have found that the year in which IQ is tested can make the difference between life and death for a death row inmate. It also can determine the eligibility of children for special services, adults' Social Security benefits and recruits' suitability for certain military careers.

That's because IQ scores tend to rise 5 to 25 points in a single generation. This so-called "Flynn effect" is corrected by toughening up the test every 15 to 20 years to reset the mean score to 100. A score from a test taken at the end of one cycle can vary widely from a score derived from a test taken at the beginning of the next cycle, when the test is more difficult, says Stephen J Ceci, professor of human development at Cornell.

Ceci and his current and former graduate students found, for example, that the number of children recommended for special services for mild mental retardation tripled during the first five years of a new test compared with the final five years of an old test, despite the fact that there were no real changes in underlying intelligence.

"Our findings imply that some borderline death row inmates or capital murder defendants who were not classified as mentally retarded in childhood because they took an older version of an IQ test might have qualified as retarded if they had taken a more recent test," Ceci says. "That's the difference between being sentenced to life imprisonment versus lethal injection." The study is published in the October issue of American Psychologist.

The researchers analyzed IQ data from almost 9,000 school psychologist special education assessments in nine school districts across the country to document how the resetting of the IQ test influences mental retardation diagnoses for several years after a new test is introduced.

The consequences of taking intelligence tests at the end or beginning of a test's cycle are most critical, however, when determining whether a death row inmate is mentally competent. Of the 350 people executed since 1990, 112 were known to have IQ scores of 70 or below (the cutoff for mental retardation).

Among children, the researchers found nearly a six-point difference between those taking the two tests. "This variance can make the difference between a child being diagnosed as mentally retarded or not," Ceci says. "This study shows for the first time that two children in the same classroom with the same cognitive ability could be diagnosed differently simply because different test norms were used for each child."

The researchers report that perhaps tens of thousands of children could be affected by these IQ trends over the course of their school years, with far-reaching financial implications. "Our results imply that millions of taxpayers' educational dollars may be misallocated because students are being misdiagnosed every year that an IQ test ages," Ceci points out.

A diagnosis of mental retardation also determines whether a person is eligible for Social Security disability benefits. And the year in which a military recruit takes an IQ test can determine whether he or she is eligible for service or certain occupations and ranks. "Caution must be used when IQ scores are used to base important financial, social or legal decisions. It may not be sufficient to simply look to see if an IQ score is below some cutoff point. The most important times to be particularly careful are when the test is either at the beginning or the end of its cycle."

Read more in American Psychologist

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Subtle Racial Bias Makes Communication Difficult

December 2, 2003

A new study highlights how even unintentional racial bias makes problem-solving difficult. The researchers found new evidence using brain imaging that white individuals attempt to control racial bias when exposed to black individuals, and that this act of suppressing bias exhausts mental resources. One would assume that it's also true the other way around.

Published in the online edition of Nature Neuroscience, the study combines the use of functional magnetic resonance imaging (fMRI), which measures brain activity, with other behavioral tests common to research in social and cognitive psychology to determine how white individuals respond to black individuals.

"We were surprised to find that brain activity in response to faces of black individuals predicted how research participants performed on cognitive tasks after actual interracial interactions," says Jennifer Richeson, Assistant Professor of Psychological and Brain Sciences, the lead author on the paper.

Their findings suggest that harboring racial bias, however unintentional, makes negotiating interracial interactions more cognitively demanding. Similar to the depletion of a muscle after intensive exercise, the data suggest that the demands of the interracial interaction result in reduced capacity to engage in subsequent cognitive tasks, say the researchers.

For the study, thirty white individuals were measured for racial bias, which involved a computer test to record the ease with which individuals associate white American and black American racial groups with positive and negative concepts. Racial bias is measured by a pattern in which individuals take longer to associate the white Americans with negative concepts and black Americans with positive concepts. The study participants then interacted with either a black or a white individual, and afterward they were asked to complete an unrelated cognitive task in which they had to inhibit instinctual responses. In a separate fMRI session, these individuals were presented with photographs of unfamiliar black male and white male faces, and the activity of brain regions thought to be critical to cognitive control was assessed.

"We found that white people with higher scores on the racial bias measure experienced greater neural activity in response to the photographs of black males," says Richeson. "This heightened activity was in the right dorsolateral prefrontal cortex, an area in the front of the brain that has been linked to the control of thoughts and behaviors. Plus, these same individuals performed worse on the cognitive test after an actual interaction with a black male, suggesting that they may have been depleted of the necessary resources to complete the task."

According to Richeson, most people find it unacceptable to behave in prejudiced ways during interracial interactions and make an effort to avoid doing so, regardless of their level of racial bias. A different research project by Richeson and her colleagues suggested that these efforts could leave individuals temporarily depleted of the resources needed to perform optimally on certain cognitive tasks. This new study by Richeson provides striking evidence that supports the idea that interracial contact temporarily impairs cognitive task performance.

These results suggest, according to the researchers, that harboring racial bias in an increasingly diverse society may be bad for one's cognitive performance. Bad for your relationships as well, I would have thought!

Read more in Nature Neuroscience

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Adolescent Steroid Use Causes Long Term Aggression

December 2, 2003

With the recent revelations about steroid use in Major League Baseball and the bust a few weeks ago of several Oakland Raiders players for drug abuse, Northeastern University psychology professor Richard Melloni, who studies the link between steroid use and aggression, has recently found evidence that use of anabolic steroids may have long-term effects on players' behavior and aggression levels well after they stop abusing these performance enhancing drugs.

Melloni and doctoral student Jill Grimes have been studying how steroids used during adolescence may permanently alter the brain's ability to produce serotonin. In their experiments, adolescent Syrian hamsters--given their similar brain circuitry to human adolescents--were administered doses of anabolic steroids and then measured for aggressiveness over certain periods of time.

In their findings, published this week in Hormones and Behavior, they conclude that there is indeed a lengthy price--namely long-term aggression--to pay for drug abuse even after the ingestion of steroids ceases.

"We know testosterone or steroids affect the development of serotonin nerve cells, which, in turn, decreases serotonin availability in the brain," Melloni says. "The serotonin neural system is still developing during adolescence and the use of anabolic steroids during this critical period appears to have immediate and longer-term neural and behavioral consequences. What we know at this point is that aggressiveness doesn't simply cease after the ingestion of steroids does."

Read more in Hormones and Behavior

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Dr Bob Murray is a widely published psychologist and expert on depression, post-traumatic stress and relationships. Together with his wife and long-term collaborator Alicia Fortinberry, he is founder of the highly successful Uplift Program, and author of the new book Creating Optimism: A Proven, 7-Step Program for Overcoming Depression (McGraw-Hill, 2004). They offer seminars, courses and audio-programs teaching people how to beat depression and improve self-esteem by creating healing relationships.

发布于10月25日 19:02 | 评论数(36) 阅读数(4472) | 我的文章

生物医学工程回顾与展望 转



生物医学工程回顾与展望 
  www.shouxi.net 杨子彬 2004-8-25 14:06:00 中国医学科学院学报2000年第22卷第3期 
  关键词: 生物医学工程(Biomedical Engineering BME) 

  生物医学工程(Biomedical Engineering,BME)是一门生物、医学和工程多学 科交叉的边缘科学,它是用现代科学技术的理论和方法,研究新材料、新技术、新仪器设备 ,用于防病、治病、保护人民健康,提高医学水平的一门新兴学科。

  生物医学工程在国际上做为一个学科出现,始于20世纪50年代,特别是随着宇航技术的进步 、人类实现了登月计划以来,生物医学工程有了快速的发展。在我国,生物医学工程做为一 个专门学科起步于20世纪70年代,中国医学科学院、中国协和医科大学原院校长、我国著名 的医学家黄家驷院士是我国生物医学工程学科最早的倡导者。1977年中国协和医科大学生物 医学工程专业的创建、1980年中国生物医学工程学会的成立,有力地推进了我国生物医学工 程的发展。目前,我国许多高校科研单位均设有生物医学工程机构,从事着生物医学的科研 教学工作,在我国生物医学工程科学事业的发展中发挥着重要作用。

  显微镜的发明 “解剖”一词由希腊语“Anatomia”转译而来,其意思是用 刀剖割,肉眼观察研究人体结构。17世纪Lee Wenhock发明了光学显微镜,推动了解剖学向 微观层次发展,使人们不但可以了解人体大体解剖的变化,而且可以进一步观察研究其细胞 形态结构的变化。随着光学显微镜的出现,医学领域相继诞生了细胞学、组织学、细胞病理 学,从而将医学研究提高到细胞形态学水平。

  普通光学显微镜的分辨能力只能达到微米(μm)级水平,难以分辨病毒及细胞的超微细结构 、核结构、DNA等大分子结构。而20世纪60年代出现的电子显微镜,使人们能观察到纳米(nm 级的微小个体,研究细胞的超微结构。光学显微镜和电子显微镜的发明都是医学工程研究 的成果,它们对推动医学的发展起了重要作用。

  影像学诊断飞跃进步 影像学诊断是20世纪医学诊断最重要发展最快的领域 之一。50年代X光透视和摄片是临床最常用的影像学诊断方法,而今天由于X线CT技术的出现 和应用,使影像学诊断水平发生了飞跃,从而极大地提高了临床诊断水平。即计算机体断层 摄影(computed tomography CT),即是利用计算机技术处理人体组织器官的切面显像。X线CT 片提供给医生的信息量,远远大于普通X线照片观察所得的信息。目前,螺旋CT(spiral CT 或helicalet CT)已经问世,能快速扫描和重建图像,在临床应用中取代了多数传统的CT, 提高了诊断准确率[1]。医学工程研究利用生物组织中氢、磷等原子的核磁共振(nu clear magnetic resonance)原理。研制成功了核磁共振计算机断层成像系统(MRI),它不仅 可分辨病理解剖结构形态的变化,还能做到早期识别组织生化功能变化的信息,显示某些疾 病在早期价段的改变,有利于临床早期诊断。可以认为MRI工程的进步,促进了医学诊断学 向功能与形态相结合的方向发展,向超快速成像、准实时动态MRI、MRA、FMRI、MRS发展。 根据核医学示踪,利用正电子发射核素(18F,11C,13N)的原理,创造 的正电子发射体层摄影(PET),是目前最先进的影像诊断技术。美国新闻媒体把PET列为十大 医学生物技术的榜首。PET问世不过30年历史,但它已显示出对肿瘤学、心脏病学、神经病 学、器官移植,新药开发等研究领域的重要价值[2]。影像学诊断水平的不断提高 ,与20世纪生物医学工程技术的发展密切相关。

  介入医学问世 介入医学是一种微创伤的诊疗技术。Dotter和Judkin(1964 年)是最早使用介入技术治疗疾病的创始人,他们用导管对下肢动脉阻塞性病变进行扩张治 疗取得成功。1967年Margulis首先使用过介入放射学(Interventional Radiology),这是医 学文献出现“介入”一词的最早记载。1977年 Gruenzing成功地进行了首例冠状动脉球囊扩 张术获得成功以后,介入性诊疗技术由于其创伤小、患者痛苦少,安全有效而倍受临床欢迎 。20世纪80年代随着生物医学工程的发展,高精度计算机化影像诊查仪器、数字减影血管造 影(DSA)、射频消融技术以及高分子(high-polymer)新材料制成的介入技术用的各种导管相 继问世,使介入性诊疗技术发生了飞速进步,临床应用范围不断扩大,从心血管、脑血管、 非血管管腔器官到某些恶性肿瘤等都具有使用介入诊疗的适应证,并使诊疗效果明显提高,患者可减免许多大手术之苦。有人把介入诊疗技术视 为与药物诊疗、手术诊疗并列的临床三大诊疗技术之一,也有人把介入诊疗技术称之为20世 纪发展起来的临床医学新领域--介入医学[3,4]。

   人工器官的应用 当人体器官因病伤已不能用常规方法救治时,现代临床医 疗技术有可能使用一种人工制造的装置来替代病损器官或补偿其生理功能,人们称这种装置 为人工器官(artificial organ)。如20世纪50年代以前,风湿性心脏瓣膜病的治疗,除了应 用抗风湿药物、强心药物对症治疗外,对病损的瓣膜很难修复改善,不少患者因心功能衰竭 死亡。而今天可以应用人工心肺机体外循环技术,在心脏停跳状态下切开心脏,进行更换人 工瓣膜或进行房、室间隔缺损的修补,使心脏瓣膜病、先天性心脏病患者恢复健康。心外科 之所以能达到今天这样的水平,主要是由于人工心肺机的问世和使用了人工心脏瓣膜、人工 血管等新材料、新技术的结果[5]。

  肾功能衰竭、尿毒症患者愈后不良,而人工肾血液透析技术已挽救了大量肾病晚期患者的生 命,肾病治疗学也因此有了很大进步。

  现代生物医学工程中人工器官的发展也非常迅速,除上述人工器官外,人工关节、人工心脏 起搏器、人工心脏、人工肝、人工肺等在临床都得到应用,使千千万万的患者恢复了健康。 可以说,人体各种器官除大脑不能用人工器官代替外,其余各器官都存在用人工器官替代的 可能性。

  此外,放射医学、超声医学、激光医学、核医学、医用电子技术、计算机远程医疗技术等先 进的医疗技术和仪器设备都是现代医学工程研究开发的成果,综上可见,20世纪生物医学工 程的发展,显著提高了医学诊断和治疗水平,有力地推动着医学科学的进步。

  21世纪生物医学工程展望 纵观医学新技术诞生和发展的 历史,从伦琴发现X线到今天X射线诊疗技术的发展,从朗兹万发现超声波到今天B超诊断的 广泛应用,从布洛赫和伯塞尔发现核磁共振到今天MRI的问世,从赫斯费尔德发明CT到今天C T成像系统的应用,都是以物理学工程技术为基础、医学需求为前提发展起来的医学新技术 。循着20世纪医学发展的轨迹,我们有理由预测21世纪新的医学诊疗技术可能在以下10个方 面有重大突破和创新:

  (1)各种诊疗仪器、实验装置趋向计算机化、智能化,远程医疗信 息网络化,诊疗用机器人将被广泛应用。[6]

  (2)介入性微创,无创诊疗技术在临床医疗中占有越来越重要的地位。激光技术,纳米技术 和植入型超微机器人将在医疗各领域里发挥重要作用。

  (3)医疗实践发现单一形态影像诊查仪器不能满足疾病早期诊断的需要。随着PET的问世和应 用,形态和功能相结合的新型检测系统将有大发展。非影像增显剂型心血管、脑血管影像诊 查系统将在21世纪问世。

  (4)生物材料和组织工程将有较大发展,生物机械结合型、生物型人工器官将有新突破,人 工器官将在临床医疗中广泛应用。

  (5)材料和药物相结合的新型给药技术和装置将有很大发展,植入型药物长效缓释材料,药 物贴覆透入材料,促上皮、组织生长可降解材料,可逆抗生育绝育材料、生物止血材料将有 新突破。

  (6)未来医疗将由治疗型为主向预防保健型医疗模式转变。为此,用于社区、家庭、个人医 疗保健诊疗仪器,康复保健装置,以及微型健康自我监测医疗器械和用品将有广泛需求和应 用。

  (7)除继续努力加强生物源性疾病防治外,对精神、心理、社会源性疾病的防治诊疗技术和 相应仪器设备的研制受到越来越多的重视与开发,研制精神分析、心理安抚、生物反馈型诊 疗技术和设备将是生物医学工程的新起点。

  (8)创伤是造成青年人群死亡的主要原因,研制新型创伤防护装置、生命急救系统是未来生 物医学工程的重要课题。

  (9)即将迎来的21世纪是分子生物学时代,有关分子生物学的诊疗新技术将快速发展,遗传 、疾病基因诊疗技术,生物技术和微电子技术相结合的DNA芯片、雪白芯片和诊疗系统将被 广泛应用。

  (10)空气污染、环境污染严重危害着人类健康,研究和开发劳动保护、家庭保健、个人防护 用的人工气候微环境是未来不能忽视的问题。

  1997年我国发布了关于卫生工作改革与发展的决定,提出了奋斗目标:“到2000年,基本实 现人人享有初级卫生保健”,到2010年国民健康的主要指标在经济发达地区达到或接近世界 中等发达国家水平,在欠发达地区达到发展中国家的先进水平。1999年国家科技部召开了“ 发展生物医学工程技术战略研讨会”,国家工程院开展了有关发展我国医疗器械工业战略研 究等,对推动生物医学工程产业发展、落实创新工程战略布置起着重要作用。20世纪人类与 疾病做斗争,在医学诊疗技术上取得了重大成就;但面向21世纪的巨大挑战,我们要动员起 来,调整政策,制定规划,改革医学研究教学的旧模式,发挥现代科学多学科交叉合作的优 势,创建全新的生物医学,为人民造福。


杨子彬(中国医学科学院 中国协和医科大学 基础医学研究所生物工程室,北京 100005)


参考文献


[1]Ge Wang Micheal WV. Preliminary study on helical CT algorithms for pati ent motion estimation and compensation .IEEE Trans. Medical Imaging,1995,14(2) :205

[2]Minn H, Lapela M, Klemi PJ et al. Predication of surviva l with fluorin-18-fluoro deoxyglucose and PET in head and neck caner. J Nucl M ed, 1997,38:1907

[3]Scheinman MM. Catheter Ablation. Circulation, 1991, 83:1489 -1498

[4]杨于彬,生物医学工程与介入性诊疗技术,世界医疗器械,1997,3(9 :50-52

[5]Katircioglu F , Yamak B,Battalogla B, et al .Long term re sults of mitral valve replacement with preservation of the posterior leaflet. J Heart Valve Dis, 1996,5(3):302

[6]Peredina A, Allen A. Telemedicine technology and clinical app lication. JAMA,1995,273:483-488

发布于10月25日 18:57 | 评论数(0) 阅读数(1044) | 我的文章

科学家有望找到人类突然入睡的原因 转

科学家有望找到人类突然入睡的原因 转

科学家有望找到人类突然入睡的原因 



录入:佚名 医学频道来源:中国科技信息网Chinainfo 点击数:558 更新时间:2005-5-25【我要评论】 【字体:小 大】 





Narcoleptic mice
image: Masashi Yanagisawa

Sudden Sleep

Researchers have spotted a chemical brain process that may explain why some people fall asleep without warning. The research was done in mice, but as this ScienCentral News video reports, it helps explain what regulates our normal sleep patterns and may lead to future treatments for people with narcolepsy. 

Sleep Mysteries

At the end of a long day, when fatigue comes wafting over our limbs and starts to tip our lids shut it seems blatantly obvious why we need sleep - we're tired. But surprisingly, why we need sleep and what exactly happens in the brain to trigger sleep is one of the greatest mysteries of neuroscience.

"It's actually the big question - why do we need sleep?" says University of Texas Southwestern Medical Center brain scientist Masashi Yanagisawa, whose research team recently came one step closer to answering that question.

Yanagisawa and his colleagues combined two established scientific techniques to identify and map, for the first time, a prominent sleep circuit in the brains of mice. They say the circuit helps balance sleep patterns in all mammals, including people, though they still don't know what tips that balance to either wake us up or put us to sleep. Yanagisawa hopes his team's map will at least shed new light on sleep's dark mysteries as well as lead to new treatments for people with narcolepsy. "We believe that our research will open up the future avenue for devising a new way of treating various sleep disorders," he says.

Yanagisawa's team focused their research in an area of the brain known to regulate sleep, called the hypothalamus. The hypothalamus is packed with different sleep regulating neurons (nerve cells). The researchers wanted to disentangle one specific set known as "orexin neurons." Orexin neurons are informally called "wake up" neurons because they are brain cells that release a hormone, called orexin, that help keeps people awake. Orexin is a chemical messenger (also known as a neurotransmitter) that travels to different parts of the brain to keep those areas awake, keeping us from falling asleep all the time. People with narcolepsy actually have weak orexin signaling systems. 

The research team already knew where these orexin neurons sent their signals, but they didn't know what activated them. To determine their power source, the researchers used a fluorescent green protein, normally found in jellyfish and developed by researchers in France as a tracer molecule. Much like a homing device, if the fluorescent molecule is injected into the brain it will "swim upstream," says Yanagisawa, through the synapses of one orexin neuron to another until it finds the original power source. But because so many different neurons are "just scattered around and completely intermixed" within the tight space of the hypothalamus they needed something even more specific. So the research team genetically modified mice to express the fluorescent molecule wherever orexin neurons were located. 

They reported in the journal Neuron that they could finally see a three-part circuit under a fluorescent microscope. The circuit ran between orexin neurons that wake us up and keep us going, histamine neurons that also help keep us awake, and a third group called "cholinergic neurons" or sleep neurons that are active when we are asleep. When the orexin and histamine neurons are active, they turn off the cholinergic or "sleepy neurons," as Yanagisawa calls them. But when the "sleepy neurons" are active they inhibit the orexin and histamine neurons. 

"So there is a triangular flip flop or seesaw switch mechanism in our brain which regulates wakefulness and sleep," Yanagisawa explains.

The researchers say this mechanism is important for maintaining sleep homeostasis - basically giving us stable periods of being awake and asleep - but the answer to the big question, what flips the switch on sleep and why we need sleep, is still unknown. They think something builds up in the brain when we are awake, "something we call sleep debt or sleep pressure," says Yanagisawa. 

Future Narcolepsy Treatment 

In the meantime, the researchers hope their new understanding of this three-part circuit will yield new treatments for people with narcolepsy. Yanagisawa says we may be able to repair failed orexin neurons "with drugs so that in the absence of those functional neurons [they] can still keep awake."

Stasia Wieber, director of the Center for Sleep Medicine at Mount Sinai School of Medicine, in New York, agrees that understanding the orexin signaling system is critical to treating narcolepsy. "Now that we understand a little bit about the feedback mechanisms and loops involved in orexin will only help to be able to use it clinically," she says.

But Wieber also stresses that this research was done in mice and has yet to be reproduced in people. She says it may be five to seven years before it could turn into a medication. For his part, Yanagisawa adds, "We [still] don't know the trigger" for sleep and says finding it will be his next step. 

Yanagisawa's research appeared in the April 21, 2005 issue of Neuron and was funded by the Ministry of Education, Culture, Sports, Science and Technology of Japan and ERATO, part of Japan Science and Technology Corporation. 

ScienCentral网5月19日消息,科学家通过研究老鼠脑细胞的化学变化过程,有望找到某些人会突然入睡的原因。科学家们对老鼠大脑进行试验后说道,通过此次研究他们有望找到人类控制睡眠的机理,并且找到治疗嗜眠病的方法。

睡眠的秘密 

工作了一天之后,人们都会感到疲惫、四肢无力、眼皮也会睁不开。也许这些就是人们需要睡眠的原因。但是,大脑如何触发睡眠机制仍然是人类神经学中的难解之谜。 

德克萨斯州立大学脑科研究专家Masashi Yanagisawa说道,“人类为何需要睡眠”长期以来一直困扰着科学家。其研究小组最近的研究为解开这个谜团前进了一大步。 

Yanagisawa及其同事研究了老鼠大脑中的“睡眠电路”,哺乳动物大脑中的“睡眠电路”可以帮助它们控制睡眠和苏醒。人类也是如此,具体是如何控制睡眠和苏醒还有待进一步研究。Yanagisawa希望他的研究小组能够找到人类睡眠的机理,并为嗜眠病患者找到治疗方法。他说道,他们的研究会给其它科学家研究人类睡眠混乱铺平道路。 

Yanagisawa的小组主要研究老鼠大脑中的下丘脑部分。下丘脑中有许多控制睡眠的神经元。下丘脑中的增食因子(Orexin)神经元会释放出一种称作Orexin的荷尔蒙,这种荷尔蒙可以帮助人们保持苏醒状态。Orexin就像是一个信史,它会传播到大脑各个部分,保持大脑各部分都处于清醒状态。患有嗜眠病的人通常在大脑中都会缺乏orexin神经元。 

研究人员已经知道Orexin神经元向大脑哪些部分发送信号,到底是什么激发了Orexin神经元产生这些信号,还是一个谜。为了找到激励源,研究人员使用一种可发光的绿色蛋白质。这种蛋白质首先发现于水母体内,主要用作追踪分子。yanagisawa说道,一旦这种蛋白质被注入大脑中的下丘脑,它就会逆流而上,从一个Orexin神经元游动到另一个,直到游到最初发出信号的源头。但是下丘脑很小,其中不同种类的神经元又很多并且混杂在一起,所以科学家对老鼠的下丘脑作了一定处理后才实施此项试验。 

他们在显微镜下最终观察到一个由三部分组成的“信号电路”。连接Orexin神经元的电路保持人们处于清醒状态,组胺神经元也具有同Orexin神经元相似的功能,类胆碱神经元则是当人们处于清醒状态时才处于活动状态,它会使人们处于睡眠状态。Yanagisawa说道,当Orexin神经元和组胺神经元处于活动状态时,它们会抑制类胆碱神经元的活动。同理,当类胆碱神经元处于活动状态时,则会抑制Orexin和组胺神经元的活动。 

Yanagisawa解释道,这样以来,大脑中就形成了一个环路,不同的神经元陆续处于活动状态,从而控制动物体的睡眠和苏醒。 

研究人员说,这种循环机制对生物体十分重要,它会防止生物体过于劳累。但是大脑如何控制这些神经元的活跃与休眠到目前为止还无人知晓。yanagisawa说道,或许当人们处于清醒状态时,体内的劳累感会不断累积,到达一定程度,自然会触发与促使睡眠有关的神经元。 

嗜眠病治疗 

研究人员同样希望他们的研究成果为治疗人类嗜眠病提供新的方法。yanagisawa说,医学家可以使用药物修复人体受损伤的Orexin神经元,使它们恢复正常的工作能力。 

许多研究人类嗜眠病的科学家也对该研究成果持肯定态度。他们说道,既然人们弄清楚了人类控制睡眠的部分机制,就应该把这些研究成果运用到临床医疗中去。 

同时值得注意的是,此项试验只是在老鼠大脑中进行,还没有真正在人脑中进行同样的试验。所以,或许科学家需要五至七年的时间才制造出治疗人类嗜眠病的药物。yanagisawa下一步的研究方向主要集中在弄清楚大脑如何控制神经元交替活动与休眠的触发机制。 

发布于10月25日 18:56 | 评论数(0) 阅读数(1019) | 我的文章

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     Since its founding in 1963, researchers at LRDC have sought to describe what learning is, where and how it happens best, how it can improve, and how research can help. LRDC scholars from several disciplines have contributed substantially to knowledge about human cognition, learning, and effective schooling and training.  Research findings are applied, in collaboration with education practitioners and business and government enterprises, to the reform and improvement of instruction and training in schools and workplaces.

     Most research projects at LRDC receive support from local and national funding organizations. Government and private funding have helped LRDC continue its study of the learning and teaching of basic cognitive skills and school subject matters, learning in the modern workplace, and the structure and components of effective learning environments. More recently, grants provided by national and local foundations have helped LRDC play a major role in educational reform and school restructuring. Several of these education projects have given LRDC a presence in a number of states and urban school districts, in this region and across the country.

 

     LRDC fosters an environment in which research initiatives relating to the science, practice, organization and technology of learning, teaching and training are born and thrive. Often, when initiatives are completed, new ideas and directions emerge. These new ideas and directions, over time, become the impetus for LRDC scholars and researchers to form new groupings.

     After several decades of quality research, LRDC has attracted diverse funding sources. Some funding sources target specific areas for their grants, which resulted in the formation of several multi-investigator research groupings, with substantial funding and strong missions. For the most part, however, LRDC will continue to maintain its mix of larger long-term multi-investigator programs operating in concert with smaller single-investigator projects.

     While all LRDC activities focus on learning, and most have links to the cognitive sciences, not all projects fit neatly into a single mission statement. All activities, nonetheless, contribute to one or more of the areas of cognitive research on learning and teaching, reform and improvement of schooling, and individual and organizational learning in the workplace. Whenever possible, LRDC makes an effort to leverage information technologies developed for, or as a result of, its work in all of these areas.


     LRDC research has illuminated the nature, forms, and processes of learning and supported the development of sound innovations in education policy and practice. In 1999, LRDC scientists and researchers are engaged in more than 50 research projects.

     A major strength of LRDC is its faculty and staff expertise.  Among its 23 faculty are education researchers, cognitive scientists, computer scientists, developmental and social psychologists, psycholinguists, evaluation and measurement specialists, organizational behavior researchers, and education policy analysts. Almost all hold joint appointments in University teaching departments (Business, Computer Science, Education, Intelligent Systems, Law, Linguistics, Political Science, and Psychology). Some have worked with LRDC for many years and bring special qualifications such as past teaching experience and extensive computer and data analysis expertise to their jobs.

     Supporting the faculty is a corps of 164 research associates, research specialists, and technical support staff. Among this corps are graduate student researchers working on LRDC-sponsored projects, part-time undergraduate hourly workers and postdoctoral fellows and research associates who come to LRDC after finishing doctoral training at other universities. The mix of new and experienced researchers offers significant training opportunities at LRDC and, at the same time, infuses LRDC with creativity and talent.  Once projects are completed, former students and postdoctoral fellows continue their work at other major universities and research laboratories.

     Evidence of the high quality of LRDC senior researchers is their outstanding publication record, election or appointment to governing positions in professional societies, memberships on major policy-making boards, and editorships of top scholarly journals. Senior scientists at LRDC serve or have served as presidents and board members of the National Academy of Education, the American Educational Research Association, the Federation of Behavioral, Psychological and Cognitive Scientists, the Society for Research in Child Development, and several divisions of the American Psychological Association.

     Senior scientists also serve on boards and committees of the National Research Council, review panels for the National Assessment of Educational Progress and other assessment programs, and numerous boards and commissions of scholarly organizations, foundations, and government bodies. They have earned many national research fellowships, honorary university degrees, and prestigious awards.  This high quality extends to support staff, many of whom also enjoy significant research and publication records.

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发布于10月25日 18:54 | 评论数(0) 阅读数(991) | 我的文章

关于生物反馈Biofeedback的三本英文书籍

print.google.com 真不错

google这个东西真不错,可以阅读许多东西。

 
Biofeedback: A Practitioner's Guide  
edited by Mark S Schwartz, Frank Andrasik
 
Provided by Guilford Press through the Google Print Publisher Program 
 
  
A Symphony in the Brain: The Evolution of the New Brain Wave Biofeedback  
by Jim Robbins
 
Provided by Grove Press through the Google Print Publisher Program 
 

Mapping the Mind  
by Rita Carter
 
Provided by University of California Press through the Google Print Publisher Program 
 

发布于10月25日 18:51 | 评论数(0) 阅读数(1141) | 我的文章

Higher level language processes in the brain: Inference and Comprehension Processes

International Hanse-Conference on

Higher level language processes in the brain: Inference and Comprehension Processes

at the Hanse-Advanced Study Institute/Germany

June, 21-25, 2003

Organized by Charles A. Perfetti and Franz Schmalhofer

Topics and objectives of conference

Over the last three decades, research on inferencing and higher-level language processes have become increasingly more important and resulted in many intriguing experimental findings (e.g., Beeman et al., 2000; Long & Baynes, 2002; McDaniel et al., 2001) as well as interesting computational models (e.g., Kintsch, 2000; Schmalhofer et al., 2002; van den Broek et al., 2001). Most importantly, this field of research features well established theories (e.g., Gernsbacher, 1990, 1997, Kintsch, 1998; O’Brien et al., 1998) that form a broad foundational consensus in the field (Graesser et al., 1997; Perfetti, 1999). Such consensual theories are of great importance for the cumulative progress in an area.

Competitive perspectives exist as well and there have even been controversies about centrally important issues regarding higher level language processes and inferencing. Examples are: (a) the alternative of working with experimentally controlled text materials (so called experimenter-generated textoids) versus naturally occurring texts such as literary texts, newspaper articles or technical exposition (Graesser et al., 1997), (b) deriving theoretical conclusions from on-line measures (such as priming in lexical decision or word pronunciation tasks, sentence reading times, eye fixation durations) or off-line measures (recognition, verification and memory recall tasks), (c) assuming a spreading-activation (McNamara, 1994) or a compound-cue mechanism (Gillund & Shiffrin, 1984) for activating information in memory (d), the debate between the minimalist (McKoon & Ratcliff, 1992) and the constructionist positions (Singer et al., 1994) and more recently, (e) the comparison between a memory-based text-processing view (e.g. McKoon & Ratcliff, 1998; O’Brien, et al., 1998) and a guided experience view of language comprehension (Zwaan, et al., 2001).

Many researchers preferred to investigate inferencing with on-line measures such as priming effects with lexical decision or word pronunciation tasks (Potts, Keenan, & Golding, 1988), reading times and eye-fixation recordings (Reichle, et al., 1998). Others have examined memory for explicit and inference sentences. Although it has already been proposed to combine these results (Graesser & Kreuz, 1993), work on this is just about to begin (cf. Van den Broek et al., 2001). Some researchers who centered their empirical work on investigating the on-line processes on inferences have suggested that the memory performance after comprehending a text are produced by quite a different mechanism. Through a compound-cue mechanism (Dosher & Rosedale, 1991; Ratcliff & McKoon, 1988;), it has thus been proposed that information is accessed in memory by a process that combines the multiple cues present in the retrieval environment into a compound cue which would then be used as a sort of fuzzy address to all those memory locations which are subsequently activated (cf. Gillund & Shiffrin, 1984). On the other hand, spreading activation mechanisms (Collins & Quilian, 1969) have been employed to explain priming effects in on-line measures of text comprehension. Although it has been pointed out that investigators are not forced to choose between an activation-based memory system and a combination of cues at the time of retrieval (McNamara, 1994), an integration of on-line activation of information during reading and memory for text has not yet been fully achieved (but see Singer & Kintsch, 2001; van den Broek et al., 2001).

The competitive experimental evaluation between the so called minimalist and constructionist positions has produced one of the most interesting debates in the field. The minimalist and memory-based text processing assumptions see inferencing as making ready a range of information of potential relevance to a reader's ongoing understanding of a text. The constructionist view assumes that inferences are drawn for the purpose of reconstructing the experience of others (i.e., the author’s experience) who are usually displaced from the reader in time an/or the physical location (Zwaan et al., 2001). This means that in natural settings, we usually read texts (i.e., a novel, a scientific publication or a newspaper article, a web page on the internet) that have been written by some other in the near or distant past. As is generally known, it is an important characteristic of human language that communication is no longer bound to the “here-and-now” of the immediate physical surroundings and humans are thereby also enabled to take different perspectives (Hockett, 1959; quoted after Zwaan, Kaup, Stanfield, & Madden, 2001). This dislocation is thus an important property of the use of symbols in the human language.

On this ground, Zwann et al. (2001) recently proposed a revision of the constructionist view that the goal of comprehension is to construct a representation of the situation referents and not the situation itself. Zwaan et al. suggest that the representations in situation models may be built from perceptual symbols. Thus, the components of the representation are encoded as the experience, and activated by verbal input as experiential simulations. Overall, Zwaan et al., provide a number of novel arguments that form a theoretical framework that may indeed be suited for integrating other empirical and theoretical work.

In his famous chapter “You can’t play 20 questions with nature and win” Newell (1973) has correctly identified some major problems of purely competitive evaluations of alternative hypotheses in experimental research. One of his conclusions was: “Thus, far from providing the rungs of a ladder by which psychology gradually climbs to clarity, this form of conceptual structure leads rather to an ever increasing pile of issues, which we weary of or become diverted from but never really settle” (p. 287-288). It does not appear unreasonable that this statement may at least temporarily hold true, for example for the minimalist versus constructionist controversy on inferencing, which had its peak in the early nineties..

In recent years, brain imaging technologies (fMRI, ERP, PET) have been applied to inferencing and more generally higher level language processes (Reichle, Carpenter & Just, 2000). Mason & Just (2001) have for example found that an inverse U-shaped relation in memory performance, that is a function of the strength of the causal connectedness of two sentences is mimicked by fMRI-data. More specifically, activation values of those areas in the right brain hemisphere that correspond to the language areas of the left hemisphere show this inverse U-shaped form. Experiments by Beeman, Bowden and Gernsbacher (2000), who use speeded responses and a lateralized presentation technique have furthermore indicated that predictive inferences start being generated in the right hemisphere before they are later on also represented in the left hemisphere. St George et al. (1997) have used evoked reaction potentials (ERP) to investigate individual differences in the generation of predictive inferences.

The purpose of the conference then is to discuss and elaborate on the foundational consensus that exists about inferencing and comprehension processes in the light of newest findings from the areas of cognitive neuroscience, behavioural cognitive psychology research and cognitive modeling techniques. Cognitive psychology research has identified the goal- and task structures which are followed when an inferencing and comprehension task is performed. The results from brain imaging research will supply information about when and where specific cognitive processes may occur in the brain. And cognitive modeling techniques have set the ground for integrating research findings across different experimental paradigms in a precise manner. As a consequence of this discussion, modifications and possibly a new conceptual structure may arise that would allow to better integrate the research findings from theses three different areas.

References

Beeman, M., Bowden, E. M., & Gernsbacher, M. A. (2000). Right and left hemisphere cooperation for drawing predictive and coherence inferences during normal story comprehension. Brain and Language, 71, 310-336.

Collins, A. M., & Quillian, M. R. (1969). Retrieval time from semantic memory. Journal of Memory and Language, 8, 240-247.

Dosher, B. A., & Rosedale, G. (1991). Judgments of semantic and episodic relatedness: Common time-course and failure of segregation. Journal of Memory and Language, 30, 125-160.

Gernsbacher, M. A. (1990). Language comprehension as structure building. Hillsdale, NJ: Erlbaum.

Gernsbacher, M. A. (1997). Two decades of structure building. Discourse Processes, 23, 265-304.

Gillund, G., & Shiffrin, R. M. (1994). A retrieval model for both recognition and recall. Psychological Review, 91, 1-67.

Graesser, A. C., & Kreuz, R. J. (1993). A theory of inference generation during text comprehension. Discourse Processes, 16, 145-160.

Graesser, A. C., Millis, K. K., & Zwaan, R. A. (1997). Discourse Comprehension. Annual Review of Psychology, 48, 163-189.

Kintsch, W. (1998). Comprehension: A paradigm for cognition. Cambridge: Cambridge University Press.

Kintsch, W. (2000) Metaphor comprehension: A computational theory. Psychonomic Bulletin and Review, 257-266.

Long, D. L., & Baynes, K. (in press). Discourse representation in two cerebral hemispheres. Journal of Cognitive Neuroscience.

Mason, R. & Just, M. (2001) How the two brain hemispheres process causal information in text: A multiple process theory of comprehending causality. Abstracts of the 42nd Annual Meeting of the Psychonomic Society, Orlando Florida, 15-18 November 2001.

McDaniel, M. A., Schmalhofer, F., & Keefe, D. (2001). What is minimal about predictive inferences? Psychonomic Bulletin and Review. 8, 840-846.

McKoon, G. & Ratcliff, R. (1992). Inference during reading. Psychological Review, 99, 440-466.

McKoon, G. & Ratcliff, R. (1998). Memory-based language processing: Psycholinguistic research in the 1990s. Annual Review of Psychology, 49, 25-42.

McNamara, T. P. (1994). Theories of priming: II, Types of primes. Journal of Experimental Psychology: Learning, Memory, and Cognition, 20, 507-520.

Newell, A. (1973). You can’t play 20 questions with nature and win: Projective comments on papers in this symposium. In W. G. Chase (Ed.), Visual Information Processing (pp. 283-310). New York: Academic Press.

O’Brien, E. J., Rizzella, M. L., Albrecht, J. E., & Halleran, J. G. (1998). Updating a situation model: A memory-based text processing view. Journal of Experimental Psychology: Learning, Memory, and Cognition, 24, 1200-1210.

Perfetti, C. A. (1999). Comprehending written language: A blueprint of the reader. In C. M. Brown & P. Hagoort (Eds.), The neurocognition of language processing (pp. 167-208). Oxford University Press.

Potts, G. R., Keenan, J. M., & Golding, J. M. (1988). Assessing the occurrence of elaborative inferences: Lexical decision versus naming. Journal of Memory and Language, 27, 399-415.

Ratcliff, R., & McKoon, G. (1988). A retrieval theory of priming in memory. Psychological Review, 95, 385-408.

Ratcliff, R., & McKoon, G. (1994). Retrieving information from memory: Spreading

activation theories versus compound cue theories, Psychological Review, 101,

177-184.

Reichle, E. D., & Carpenter, P. A., & Just, M. A. (2000). The neural basis of strategy and

skill in sentence-picture verification. Cognitive Psychology, 40, 261-295.

Reichle, E. D., Pollatsek, A., Fisher, D. L., & Rayner, K. (1998). Toward a model of eye-movement control in reading. Psychological Review, 105, 125-157.

Schmalhofer, F., McDaniel, M. A., & Keeffe, D. (2002). A unified model for predictive and bridging inferences. Discourse Processes. 33 (2), 105-132.

Singer, M., Graesser, A. C., & Trabasso, T. (1994). Minimal or global inferences during reading. Journal of Memory and Language, 33, 421-441.

Singer, M. & Kintsch, W. (2001). Text retrieval: A theoretical exploration. Discourse Processes, 31, 27-59.

St. George, M., Mannes, S., & Hoffman, J. E. (1997). Individual differences in inference generation: An ERP analysis. Journal of Cognitive Neuroscience, 9, 776-787.

van den Broek, P., Tzeng, Y., Virtue, S., Linderholm, T., & Young, M. (2001). Inference making and memory for text: A computational model. Abstracts of the 42nd Annual Meeting of the Psychonomic Society, Orlando Florida, 15-18 November 2001.

van Dijk, T. A., & Kintsch, W. (1983). Strategies of discourse comprehension. San Diego, CA: Academic Press.

Zwaan, R. A., Kaup, B., Stanfield, R. A., & Madden C. J. (2001). Language comprehension as guided experience. (http://cogprints.soton.ac.uk/documents/)

发布于10月25日 18:38 | 评论数(0) 阅读数(1147) | 我的文章

Bioelectromagnetism Matlab Toolbox

Bioelectromagnetism Matlab Toolbox

Powered by Matlab Logo

Distributed by SourceForge Logo

License

GNU

This toolbox is released under the GNU General Public License (GPL, see http://www.gnu.org/licenses/gpl.html). This is a copyleft license, which means you have the freedom to use, distribute and modify the code, but only on the condition that you must pass on this freedom. You can integrate this code into proprietary packages, but you must do so according to this rule. That is, some parts of your proprietary package will not have this freedom, but those parts derived from this code must retain that freedom. You must use, distribute and develop the code herein in accordance with the GPL.

EEG Features

Firstly, this is not a signal processing toolbox. Of course, once the data is loaded, there are many matlab functions available for data processing, but few of them are integrated into a GUI interface here. At present, there are no specific functions for processing raw EEG, such as filtering, averaging, etc. For examples of signal processing tools, see the matlab signal processing toolbox and the links below, especially EEGLAB.

This toolbox has been developed to facilitate quick and easy import, visualisation and measurement for ERP data. The toolbox can open and visualise ERP averaged data (Neuroscan, ascii formats), 2D/3D electrode coordinates and 3D cerebral tissue tesselations (meshes). All the features can be explored quickly and easily using the example data provided in the toolbox. The GUI interface is simple and intuitive. The following lists the features already available and some items that could be developed.

ERP Visualisation

  • ERP data can be read and plotted as a time series
  • Automated or GUI entry of ERP epoch/sampling etc. parameters
  • Interactive, precise measurement of ERP waveform values
  • Interactive ERP peak detection and plotting/measurement
  • Interactive ERP topographic mapping

Data Import/Export Support

  • Neuroscan EEG formats (.avg,.eeg,.cnt)
  • Neuroscan electrode formats (.tri, .3dd ascii)
  • EMSE electrode and mesh formats (.elp/.wfr/.reg)
  • FreeSurfer mesh formats (.tri/.asc/.surf/.curv/etc)
  • BrainStorm formats
  • All data is stored internally in one large, convenient data structure (p), which is available from the matlab workspace.

Topographic Mapping

If the electrode position data is available or adapted from the standardized electrode positions available, the toolbox can generate topographic maps. There are various topography options, including 2D/3D surface mapping with various controls for contour mapping, scaling, and colour maps. If a scalp tesselation is available, the toolbox can load and visualise the 'mesh' and interpolating from the electrodes onto the mesh (only when they are already coregistered - the functions for coregistration are in early stages of development).

  • standardized extended 10/20 electrode coordinates available
  • example realistic geometry, with 124 channel electrode coordinates and associated scalp/skull/cortex tissue meshes from MRI volume provided
  • latency selection for topographic mapping based on single values, either entered manually or interactively selected
  • animation of topographic maps
  • automatic or user-defined amplitude scales
  • various color or bw topographic maps (linear or polynomial color scales)
  • contour topographic mapping, with automatic or user-defined intervals or numbers of contours specified (rudimentary at the moment - needs refinement)
  • Printing or saving graphics files (various formats)
  • 3D rotation and left,right,front,back views of 3D topographic maps

The following graphic illustrates 3D scalp topography (with interpolation from 124 electrodes onto a scalp mesh). As of May 2002, the methods are integrated with the GUI interface (they are available in the mesh_laplacian.m and mesh_laplacian_interp.m functions). Many thanks to Robert Oostenveld for assistance in validating these functions.
scalp interpolation

Data Transforms/Analysis

  • Identification/replacement of bad electrodes
  • ERP peak detection for all electrodes
  • ERP peak detection for regions of electrodes

MRI Features

There are useful functions to load and visualize MRI volumes in Analyze format (or the Freesurfer COR- format and GE Signa files). The Analyze avw* functions have been developed to carefully handle the orientation and implement a strict interpretation of the original Analyze 7.5 specification. This specification is available here in two very informative pdf documents:

If you need to, use the orient option in the avw* functions to handle different image orientations, but read the above documents and this discussion on the issue first (you will be wise in no time).

Also, when working with format conversions, consider these enlightening notes from Mark Jenkinson!

It is expected these MRI functions, together with mesh functions, will provide the opportunity to visualize mesh overlays with MRI volumes. It is also creates an avenue for conversion of MRI volumes. There are some MRI processing functions freely available for matlab, some of them are bundled into the CVS archives, but none are integrated into GUI interfaces yet.

For further MRI processing functions, see the matlab image processing toolbox, the SPM toolbox for matlab, and the FSL tools (in c/c++ with source code available).

System Requirements - Development Platform

The development of this matlab toolbox is in its infancy. It is not very clear what the system requirements are, although matlab 6+ is required. I understand from one report that the toolbox GUI does not work under matlab 5.x, but many command line functions should be OK. For most ERP plotting, the toolbox creates about 4-8Mb of data in the workspace and GUI. For more elaborate mesh plotting and interpolation, the toolbox can create up to 40Mb of workspace data (probably that much again in the GUI itself).

The toolbox has been developed on matlab 6.x on a windows platform. I have noticed some minor problems with mesh plotting and interpolation on systems without OpenGL graphics.

Download

CVS Access

A CVS client is required to checkout files from the CVS archive. CVS clients are available for every major operating system, eg:

  • Microsoft Windows: TortoiseCVS
  • Linux, BSD and Mac OS X: CVS (normally provided by your operating system vendor)
  • Mac OS X: fink CVS
  • Macintosh classic: MacCVS Pro

To view the modules in this project, use the www interface to the CVS repository. The module to check out is 'bioelectromagnetism' (previous modules, 'eeg_toolbox' and 'mri_toolbox' are no longer developed, their functions are all in 'bioelectromagnetism'). The CVS repository can be checked out through anonymous (pserver) CVS with the following instructions (when prompted for a password, simply press Enter).

cvs -z3 -d:pserver:anonymous@cvs.sf.net:/cvsroot/eeg checkout bioelectromagnetism

Updates from within the module's directory do not need the -d parameter.

Installation for Matlab

Extract it to a folder on your matlab path or use the 'addpath [bioelectromagnetism folder] -end' command to append a new folder to your matlab path.

Email Support List

To ask questions or keep informed of updates, subscribe to eeg-users. If you want to know about changes to functions, the cvs service provides automatic notification to the developers email list, so you can also subscribe to eeg-developers. This list is not for questions about how to use the functions.

Getting Started

See the getting started guide.

Documentation

See the auto-html documentation bioelectromagnetism, with similar info also available by typing 'doc bioelectromagnetism' at the matlab command prompt. This documentation provides html access to the information otherwise availabe using 'help [command]', once the toolbox is installed under matlab. In addition, it provides clear dependency links between functions in the toolbox. It was generated automatically by m2html.

Script Processing

It is possible to run all of the functions in the toolbox from the command prompt or a matlab script. Script and function names are intended to be loosely descriptive of their purpose (scripts have the _script.m extension). At this stage, most of the scripts and functions have been developed and tested on limited dataset specifications, so be careful to verify operations on your data. A couple of scripts may be under development and will not work at all. It is best if you have some familiarity with programming in matlab so that you can modify some script variables, which are defined at the outset of a script.

GUI Layout Problems?

There is no guarantee that GUI interfaces will appear correctly on different matlab platforms. It is developed on windows98, matlab6.0 (R12), but some of the text and boxes may not scale correctly on other systems. The toolbox uses normalized scaling for all GUI widgets, which should display and resize OK on any platform, but the matlab handlers seem to work differently with different display systems (X, windows, etc). Please just try resizing the GUI window until it looks OK for you.

If you find the toolbox useful and wish to modify the GUI, please have a look at the gui*.m files to adjust the size of widgets, figures or whatever. If you do tidy up the code for your system, please email your modifications to me with an indication of what is modified for what system. If you have the time and inclination, please register as a sourceforge developer and make arrangements to integrate your development efforts with the cvs repository.

Developers

To development the toolbox, first consider the data structure. All the data is integrated into fields of the p struct, which is easily passed into the functions. At this early stage of the project, there is a degree of fluidity and flexibility, which may facilitate integration of this toolbox with similar projects, such as EEGLAB.

To fully engage the CVS repository, first get an account with sourceforge and then follow the sourceforge instructions to register and to setup your ssh/cvs access to the toolbox source code. The ssh/cvs setup and development process is made easy by reading the introduction materials at http://sfsetup.sourceforge.net. Also, subscribe to eeg-developers.

Development

Recently Done

  • Histogram and ROI functions for MRI viewer (avw_view)
  • Spherical spline interpolation (not in GUI yet)
  • average reference transform
  • global field power and global dissimilarity index

To Be Completed

  • interactive topographic map measurements (single value or local max/min)
  • realistic surface spline interpolation
  • incorporate analysis tools into GUI
  • Access to time-series filtering from the GUI (eg, signal processing toolbox)
  • GUI display of .eeg and .cnt EEG formats. There are no GUI facilities for viewing or manipulating epoched or continuous EEG at present. There are some command line functions to read Neuroscan data in these formats.
  • Other data formats. If you want to load a data format other than those available or you have a function that loads an alternative data format, please forward an example data file and description of the data format (or matlab function to read it). Please first see the link to a useful list of file formats for which matlab functions are available below.
  • MRI segmentation and tesselation (possibly based on FSL routines)
  • tesselation orientation and metric conversions
  • Integration with the EEGLAB and Brainstorm toolboxes? Some conversion functions for BrainStorm are available, but nothing yet for ICA.

Other EEG/ERP matlab links

Some MRI and Visualization links


Darren.Weber_at_radiology.ucsf.edu, Last Modified 10/06/2005 06:04:15

发布于10月25日 17:17 | 评论数(17) 阅读数(20981) | 我的文章

Keiichi Kitajo's website

Keiichi Kitajo's website                  

Contact Information                         Home      Japanese

Keiichi Kitajo, Ph.D. (Kei)

Research Scientist
Lab. for Dynamics of Emergent Intelligence
RIKEN Brain Science Institute(BSI)

2-1, Hirosawa,Wako-shi, Saitama
351-0198 Japan

Honorary Research Associate
Psychophysics and Cognitive Neuroscience Laboratory (Prof. Lawrence M. Ward)Department of Psychology, University of British Columbia (UBC)

2136 West Mall, BC, V6T1Z4, Canada


E-mail kkitajo@brain.riken.jp, kitajyo@p.u-tokyo.ac.jp, kkitajo@psych.ubc.ca

Nationality Japanese

 Current Projects                            
1.Stochastic resonance (SR) within the human brain
Visual SR
Auditory SR
Crossmodal SR

2.Stochastic resonance and synchronization in the brain
SR and Large-scale Synchronization of the human brain (EEG potential and Scalp current density)

3.Higher cognitive function and Stochastic resonance
SR in multi-stable perception (attention, ambiguous figures etc..)

4.Ongoing activity and SR

Keywords
Noise, perception, synchronization, stochastic resonance, brain, EEG, Auditory steady-state response, attention


Selected Publications and Presentations (International Conferences, Journals, etc.)  Please don't hesitate to contact me if you need reprints or pdf files!

K. Kitajo, RIKEN BSI seminar. Stochastic resonance within the human brain. 2005.

K. Kitajo, K. Yamanaka, L. M. Ward and Y. Yamamoto, Stochastic resonance in attention control. submitted

K. Kitajo, K. Yamanaka, L. M. Ward and Y. Yamamoto, Stochastic resonance in attention switching. Proceedings of SPIE 5841: 49-56, 2005.

S. Doesburg, K. Kitajo, L. M. Ward, Gamma-band synchrony precedes switching of conscious perceptual objects in binocular rivalry. NeuroReport 16: 1139-1142, 2005.

K. Kitajo, K. Yamanaka, D. Nozaki, L. M. Ward and Y. Yamamoto,  Frequency-specific, noise-influenced neural synchrony and detection of visual signals. submitted

K. Kitajo, K. Yamanaka, D. Nozaki, L. M. Ward and Y. Yamamoto, Behavioral stochastic resonance is associated with large-scale synchronization of human brain activity. Proceedings of SPIE 5467:359-369, 2004.

K. Kitajo, D. Nozaki, L. M. Ward and Y. Yamamoto, Behavioral stochastic resonance within the human brain. Physical Review Letters 90: 218103, 2003.

K. Kitajo, D. Nozaki, L. M. Ward and Y. Yamamoto, Behavioral stochastic resonance in the human brain. Fluctuations and Noise in Biological, Biophysical, and Biomedical System, Santa Fe USA ,  Proceedings of SPIE 5110: 252-261, 2003.

K. Kitajo, D. Nozaki and Y. Yamamoto, Human perception-action coupling enhanced by stochastic resonance. First SIAM (Society for Industrial and Applied Mathematics) Conference on Life Sciences, Boston USA ,2002.

K. Kitajo, Inter-blink interval and human cognition. Measurements, analyses, and modeling of spontaneous rhythmicity in biosignals. ; International Scientific Research, Ministry of Education, Science and Culture: Joint Research Program on "Functional Role of Noise in Physiological Control Systems". Tokyo , Japan , 2000.

K. Kitajo, C. Fukusaki, Y. Yamamoto, H. Yano and M. Miyashita, Development of the inhibitory system in human spinal cord.  Third World Congress of Biomechanics, Sapporo , Japan , 1998.

K. Kitajo, M. Shirayama and M. Miyashita, Elbow movement patterns predicted by means of an artificial neural network. XI th Congress of the International Society of Biomechanics, Jyuvaskyla , Finland , 1995.

K. Kitajo M. Shirayama, and M. Miyashita Neural Networks Learning EMG-Torque Relationship during Voluntary Isometric Knee Extension. Japanese Journal of Sports Sciences. 1995.

 

Media coverage of our researches

Static on the Brain. Physical Review Focus, --30 May 2003
Eye can see better when it’s noisy. NewScientist, --7 June 2003
Virtual Journal of Biological Physics Research, Volume 5, Issue 11, -- 1 June 2003
Kyodo news -- 3 July 2003
Noise aids perception. Cern Courier, Volume 43, Number 6, 2003
Wissenschaft-online 2 June 2003
Wissenschaft.de 5 June 2003 
Scinews.ru  
ECPLANET

Awards
Japanese Society of Biomechanics: 1994 New Investigator Award. Learning and prediction of EMG-Torque relationship using artificial neural networks.

Grant Awards
Principal Investigator, Grant-in-Aid for Scientific Research, Ministry of Education, Science and Culture, Japan (2001-2002). Relationship between spontaneous eye blinking and human cognition during voluntary movement.

Principal Investigator, Grant-in-Aid for Scientific Research, Ministry of Education, Science and Culture, Japan (1999-2000). Changes in visual and somato-sensory information processing during human motor learning.

Principal Investigator. Research Award of Casio Science Foundation, Japan (1999). Effect of human cognitive process on eye blinking - Development of portable measurement device for eye blinking -. 

My interests
Brain, Synchronization, Noise, Perception, Soccer football, Pumping iron, Alpine skiing

Tools
OS Linux (Turbolinux)
, MS Windows, Mac OS X, Unix (Solaris)

Psychophysics 
Presentation (Neurobehavioral systems)  
Psychophysics toolbox  (matlab free toolbox) 

Data anayses
Matlab, Siganl processing Toolbox, Matlab Compiler
, EEGLAB

Mathematica, Gnuplot, Igor, GIMP
Miktex Tex, TexnicCenter, SAS  

Programming languages
C/C++, Visual Basic
, Visual C++, Gawk, OpenGL, Matlab

发布于10月25日 17:00 | 评论数(0) 阅读数(1430) | 我的文章

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