COMET • Vol. 2, No. 20 – 29 May 2001

Editor’s note: This is the last regularly-scheduled issue of COMET until September. The focus of this special issue is current research in the neurosciences.

May you find time for recreation, reflection, and rejuvenation this summer!


*Announcement for San Joaquin Valley Educators*


A wine and hors d’oeuvres reception will precede a presentation by Liping Ma, author of Knowing and Teaching Elementary Mathematics, at California State University, Fresno on 13 June 2001. The reception will be held from 6-7 p.m. at the Smittcamp Alumni House (NE corner of Maple and Shaw Ave., Fresno; free parking is available nearby in Lots C and V). The presentation will conclude at approximately 9:00 p.m. Everyone in attendance will receive a bookplate signed by Liping Ma.

If you are interested in attending, please send me an email message to that effect by June 5. A check covering the registration fee of $20 may be made out to the San Joaquin Valley Mathematics Project (SJVMP) and mailed to the address in my signature line below by June 8. This event is being co-sponsored by the SJVMP, the Fresno County Office of Education, the California State University, Fresno Science and Mathematics Education Center, the Kremen School of Education and Human Development, and the College of Science and Mathematics (CSUF).

Special Issue: Current Research in the Neurosciences

(1) “Brain Can Produce New Memory Cells”

Source: MSNBC News – 14 March 2001

In a finding that could be good news for stroke sufferers and people with brain diseases, scientists said on Wednesday that the brains of animals and humans can produce new cells that can help to form memories.

Researchers had been skeptical about the brain’s ability to grow new cells. But behavioral neuroscientists at Rutgers and Princeton universities in New Jersey have shown not only that the brains of rats produce new cells, but also what they do.

“It appears that the new neurons become involved in memory about a week to two weeks after they are generated, and they are involved in memories normally handled by the hippocampus (an area of the brain),” said Professor Tracey Shors of Rutgers.

She and her colleague Elizabeth Gould, of Princeton University, believe their research suggests that the brain’s recuperative powers may have been underestimated and could be far greater than scientists had previously thought.

“I think the idea that the brain continues to make new neurons and that those neurons serve an important function gives us hopes that we can restore function in people who have neurone loss,” Shors said…”On another level it may give ideas about trying to enhance the self-renewing capacity of the brain.”

Jeffery Macklis, of Harvard Medical School in Massachusetts, went one step further, suggesting that the research could have implications for the treatment of brain injuries or diseases. “The results also support the idea that it might, one day, be possible to add new, fully functional neurons into existing brain circuitry to treat diseases of the nervous system,” he said in a commentary on the research…The researchers are trying to identify exactly what role the cells play in memory, and how sex differences influence memory and the generation of new neurons.


(2) “Musical Training During Childhood May Influence Regional Brain Growth”

Source: EurekAlert! – 8 May 2001

Research has revealed significant differences in the gray matter distribution between professional musicians trained at an early age and non-musicians… The musicians in the study had more relative gray matter volume in left and right primary sensorimotor regions, the left more than the right intraparietal sulcus region, the left basal ganglia region and the left posterior perisylvian region, with pronounced differences also seen in the cerebellum bilaterally.

“We were interested to know whether intense environmental demands such as musical training at an early age influenced actual brain growth and development,” comments study leader Gottfried Schlaug, MD, PhD. Results of this cross-sectional study may indicate use-dependent brain growth or structural plasticity of gray matter volume in response to such demands during a critical period of brain maturation. “An alternative explanation may be that these musicians were born with these differences, which may draw them toward their musical gifts.” Fifteen male professional musicians and 15 age and gender matched non-musicians were included in the study conducted by neurologist Schlaug and Gaser Christian, PhD, of Germany, at the Beth Israel Deaconess Medical Center, Boston. Using a magnetic resonance imaging sequence, they compared high resolution anatomical datasets of the professional musicians’ and non-musicians’ brains on a voxel-by-voxel basis using SPM99 software.

“Musicians typically commence training at an early age, making them ideal subjects for this type of investigation,” notes Schlaug. These presumed cerebral adaptations may not only lead to modifications of functional sensory and motor maps, but may also lead to structural adaptations within the sensorimotor system…


(3) “Brains Doing Math Add to Knowledge of ADHD”

Source: Education Week – 9 May 2001

…Brain scans were taken while the subjects performed mathematical calculations involving serial addition. The results show significant differences between the thought processes of the subjects with attention deficit hyperactivity disorder and those without ADHD. The yellow spots show regions of the brain where blood flow increased during performance of the task…

The subjects without ADHD showed more activity in the frontal part of the brain that is associated with attention. Also, those subjects used the middle regions of their brains associated with processing verbal strategies. The researcher, Julie Schweitzer, says that is because the subjects without ADHD seemed to hear the auditory prompt and talk themselves through the problem using words.

In contrast, the subjects with ADHD used different parts of their brains associated with visualization. Schweitzer says some of the subjects diagnosed with the disorder told her after the test that they had pictured images in their heads–for example, a chalkboard with numbers written on it–to help in doing the calculations.


(4) “Pointing the Finger”

Source: The Economist – 22 March 2001

A child’s future really may be written in his hands–not in the creases of his palms but in the relative lengths of his fingers. A report just published in Developmental Medicine and Child Neurology suggests that people with autism have ring fingers that are abnormally long compared with their index fingers…

The relative sizes of someone’s fingers are fixed for life within three months of conception, and the relationship seems to be governed by testosterone. Although the reason is not yet understood, earlier studies have shown that finger-length ratios are a robust marker of how much of that hormone a baby has been exposed to in utero–the more testosterone, the longer the ring finger. Overall, therefore, men tend to have longer ring fingers than index fingers, whereas in women the two fingers are more likely to be of equal length.

Dr. Manning and Dr. Baron-Cohen found that autistic children had extremely long ring fingers compared with their index fingers. Children with Asperger’s also had abnormal index-to-ring finger ratios, though less so than full-blown autistics. Even the unaffected siblings and parents of the autistic children had ratios that differed significantly from the normal controls.

That may sound surprising, but high levels of testosterone in the womb have been linked to several other brain-related phenomena, including left-handedness, dyslexia and female homosexuality. Dr. Manning thinks that the families of autistic children are genetically predisposed to produce high levels of testosterone during early development. (The fetus makes most of the testosterone itself. In males, it comes from the testes and adrenal glands; in females from the adrenals alone. Only a small amount, if any, comes from the mother.)

While high levels of testosterone may not solve the whole puzzle of autism, Dr Manning thinks levels in utero may be an important piece of it. The finding bolsters what is known as the “extreme male brain” theory of autism. As the name suggests, autism–which is, in any case, much more common in men than women–may simply be an extreme magnification of traits, such as problems with communication and empathy, that psychological testing has shown…are more frequently found in men.


(5) “Dyslexia Caused By Brain Defects, Study Indicates” by Mark Henderson

Source: The Times (UK) – 16 March 2001,,2-99928,00.html

Evidence that dyslexia is caused by neurological abnormalities in the brain rather than cultural and linguistic factors has been discovered by scientists.

A comparison of the brains of dyslexic English, French and Italian speakers has shown that the condition has the same biological basis in all three groups, even though the prevalence of reading disorders varies widely.

The findings, published today in Science, offer the first firm evidence that it is an identifiable neurological phenomenon, in which the brain processes language in an unusual way. Although research has pointed towards this, scientists have doubted the link because it has long been established that rates of dyslexia, or at least of the reading problems that it causes, vary widely.

In countries such as Britain, the United States and France, where the language is complicated to write, dyslexia is diagnosed more frequently than in countries such as Italy, where the written language mirrors its spoken form more closely…

The team, led by Uta Frith, Professor of Cognitive Development at University College London, found that although Italian dyslexic people performed better than the English and French dyslexic people at reading tests, the groups did equally badly at the short-term memory tests. The PET scans showed similar brain activity among all volunteers during both tests, with reduced activity in the left temporal lobe–the part of the brain that processes language.

Professor Frith said the results indicated that the underlying neurological basis of dyslexia was the same, no matter what language the sufferer speaks. The condition, however, is more likely to cause reading difficulties in languages that are complex to write. In English, there are 1,120 ways of representing 40 sounds with different combinations of letters. It is difficult to know how to pronounce words such as “pint” and “mint” without learning them in advance.

Italian has 33 ways of representing 25 sounds; letter groups usually signify the same sound. Professor Frith said: “It highlights the impact that the complexity of orthography (the writing of sounds) can have on reading proficiency of people with dyslexia. “In the Italian population there may be hidden cases of dyslexia. Mild cases of dyslexia may appear far worse in irregular orthographies.”

Eraldo Paulesu, of the University of Milan-Bicocca, who contributed to the study, said: “The addition of data from French subjects reinforces findings that languages with complex orthographies are difficult for both dyslexics and non-dyslexics to read.”

Juliette England, of the British Dyslexia Association, said: “This really endorses that in dyslexia, the brain functions in a different way. It shows that dyslexia doesn’t have to be a handicap, and that it doesn’t mean you’re stupid.”


(6) “Anatomy of a Stutter” by Rachel K. Sobel

Source: U.S. News – 2 April 2001

…More than 3 million people in the United States–and 55 million around the world–wrestle with this devastating and isolating disorder every day…What causes these people to trip up? “The simplest 4-year-old is more fluent than you,” says Gerald Maguire, a psychiatrist who has stuttered for most of his 35 years. Indeed, the vagaries of the disorder have stumped scientists for generations. Why, for instance, do whispering, acting, talking to pets, and singing often make the disability disappear? Why does it occur roughly four times as often in men as in women? And why do some children eventually outgrow it?

A small yet energized group of researchers is now making headway toward a new scientific understanding of this ancient affliction. Coming from a variety of fields, including neuroscience and radiology, genetics and speech pathology, these scientists have begun to uncover the biological roots of this enigmatic disorder. “For a long time, stuttering was thought to be psychogenic, rooted purely in psychology,” says Allen Braun of the National Institute on Deafness and Other Communication Disorders. “That’s clearly not the case now.”

Now the focus is on genes and the inner workings of the brain. Investigators announced last November at the American Speech-Language-Hearing Association meeting that they had found the first tangible evidence of a genetic aberration underlying at least some cases of stuttering. What’s more, new PET imaging studies have revealed striking differences in the brain physiology of stutterers and nonstutterers. Stutterers, it turns out, may be using the wrong side of their brains when they speak. “The right hemisphere seems to be interrupting or interfering with the left hemisphere,” says Peter Fox, neurologist and director of research imaging at the University of Texas Health Science Center…

Roger and Janis Ingham, professors of speech and hearing sciences at the University of California-Santa Barbara, have been peering into the brains of dozens of stutterers with PET scans to find out what is going awry. Over the past few years, and most recently in the November issue of Brain, the duo, working with UT’s Fox, have reported evidence of neurological “miswiring,” primarily in the right side of stutterers’ brains. PET scans of nonstutterers show both hemispheres lighting up when they speak, with more activity on the left. By contrast, a stutterer has more hot spots on the right, possibly interfering with what should be left- sided speech production. When stutterers have moments of fluency, interestingly enough, their scans start to resemble those of nonstutterers.

The researchers also found that a region of the brain that processes hearing is deficient in stutterers while they are speaking. This region is active in fluent speakers, but it’s nearly silent in stutterers. The finding seems to indicate that the stutterer is tuning himself out as he’s trying to speak, thus contributing to or simply blocking out the stammering speech…

All of this aberrant neural activity probably sends faulty messages to the main speech-producing muscles–the vocal cords, tongue, diaphragm, and lips. “Stutterers don’t have a problem planning a message. They have adequate language and grammar skills,” says Janis Ingham. “Where they lose it, it looks like, is in selecting speech sounds, sequencing them, and figuring out which muscles need to be turned on or off to produce them”…

One team of researchers, led by University of Illinois-Urbana-Champaign scientist Nicoline Ambrose, discovered through statistical analysis of inheritance patterns that stuttering may be due to a single major gene along with a few less important ones..

If the exact mechanisms can be worked out–which genes, how those genes create proteins, and how those proteins function in the disorder–scientists foresee a future in which stuttering could be treated like other medical problems. “Nervousness is not a molecule we can do something about,” says Drayna. “Genes and proteins are”…

In the end, scientists hope their findings will help debunk stereotypes and stigmas, even among stutterers themselves. “People who stutter are relieved to find out that they are not crazy, that they don’t have a defective personality,” says Janis Ingham. “To know ‘my brain is different than yours but my soul isn’t’ is a tremendous thing.”


(7) “How Sleep Benefits the Brain”  

Source: MSNBC News – 25 April 2001

Researchers at the University of California at San Francisco found that sleep dramatically enhances changes in brain connections during a vital period of visual development in young cats…

“Young animals and human babies sleep a whole lot more than they do when they get older,” Stryker said. “And this is precisely the time in life when the connections in the brain are being reorganized to attain the perfect precision that they have in normal adults”…

The study represented strong evidence that one function of sleep is to help consolidate the effects of waking experience on cortical plasticity, putting memories into permanent storage, Stryker said. While the study examined sleep’s effect on young cats, sleep may play a similar role in older animals and people, he added.


“There may be similar phenomena going on in other areas of the brain later in life,” Stryker said. “I think it’s likely to be true that other areas of the brain, higher areas of the brain, have their critical (developmental) periods later in life–and some of them, in the highest areas, the critical periods never close until senility.”


The study found the amount of plasticity in the brain depended on the amount of sleep known as non-rapid eye movement–the deep, quiet sleep marked by large, slow brain waves…


(8) “Brain Research Oversold, Experts Say” by Valerie Strauss

Source: Washington Post – 13 March 2001
(Link from, graphic of the brain)

D.C. School Superintendent Paul L. Vance often says he plans to revamp early childhood education with the “latest brain research.” The only problem: Top brain researchers say it can’t be done.

“You can’t go from neuroscience to the classroom, because we don’t know enough neuroscience,” said Kurt W. Fischer, director of the Mind, Brain and Education program at Harvard University’s Graduate School of Education.

Brain science, to be sure, has in recent years revealed fascinating insights that will help revolutionize human understanding of the species. One day, its findings may have broad applications for education, and there is evidence that it can help students with specific learning disabilities today. But it cannot yet tell most teachers what or when to teach or how to organize their curriculum, many experts say…

There is, to be sure, a wealth of knowledge about human development learned over time by behavioral and social scientists and others, said Jack Shonkoff, dean of the Heller Graduate School at Brandeis University.

And the growing prominence of neuroscience has led to increased cooperation among fields, which Ken Whang, a program director for the National Science Foundation’s Research on Learning and Education program, said is the key to progress in improving education.

But policymakers and educators often ignore or misinterpret what is known to be effective in learning, Shonkoff and others said… Environment matters, the National Research Council report said, though educators and legislators stress test scores and other things that do nothing to create such bonds.

Vance has said he wants to revamp early childhood education based on brain-based research suggesting that language development ought to begin as early as age 3. Experts say early musical and language stimulation is important. But the report, titled “From Neurons to Neighborhoods,” says there is “no sharp break at age 3 (or 5).”

Neuroscience both confirms and contradicts common beliefs about learning and memory.

It was once thought that humans learn far more in the early years than in adulthood, partly because brain neurons and synapses were thought to be created only in utero and during the first year of life. It was recently discovered that they grow throughout life, supporting lifelong learning…

Research has also shown the brain to be flexible. The phenomenon, called “plasticity,” occurs when the organ changes structure depending on what activity a person is performing, said the University of Chicago’s Peter Huttenlocher, a leading brain expert.

For example, British researchers showed that London taxi drivers — who do extensive training before hitting the streets — have larger hippocampuses, the part of the brain involved in spatial learning, than non-taxi drivers. Size depended on how long they had been driving taxis…

John Ratey, a Harvard University psychiatrist and author of “A User’s Guide to the Brain,” said children who learn musical instruments before reading and math have an advantage because that part of their brain is already built up. But other scientists disagree.

Researchers are investigating the controversial idea of critical periods in human development — that the brain can receive information only at a certain age — and sensitive periods when the brain is more open to learning certain things. Experts, not surprisingly, disagree…

But Fischer said there are times when new cognitive capacities and brain connections are growing suddenly — at about 4 months, 8 months, 12 months, 2 years, 4 years, 7 years, 10 years, 15 years, and 20 years (and probably at a few more times in the first few months of life and at least one more at 25).

Where researchers do seem to agree is that brain research will first help students with specific learning disabilities…

But much work remains to be done.

“There is an enormous body of brain research, but with the brain being easily the most complicated thing we know about in the universe, we really still understand very little about it,” said Bryan D. Fantie, director of the Human Neuropsychology Laboratory and Behavioral Neurosciences Doctoral Program at American University.


(9) “Read My Mind”

Source: New Scientist Magazine – 27 January 2001

…Psychologists and neuroscientists alike have been baffled by our ability to anticipate other people’s behavior and empathize with their feelings. Now a team of Italian neurophysiologists may have stumbled on the key to this mystery.

Vittorio Gallese, Giacomo Rizzolatti and their colleagues at the University of Parma have identified an entirely new class of neurons. These neurons are active when their owners perform a certain task, and in this respect are wholly unremarkable. But, more interestingly, the same neurons fire when their owner watches someone else perform that same task. The team has dubbed the novel nerve cells “mirror” neurons, because they seem to be firing in sympathy, reflecting or perhaps simulating the actions of others.

Many neuroscientists are starting to think that in higher primates, including humans, these neurons play a pivotal role in understanding the intentions of others. “Mirror neurons may be one important part of the mosaic that explains our social abilities,” says Gallese. Vilayanur Ramachandran of the University of California at San Diego goes further. He believes that mirror neurons will answer important questions about human evolution, language and culture–and may take us to the heart of what it means to be human. “I predict that mirror neurons will do for psychology what DNA did for biology,” he says. “They will provide a unifying framework and help explain a host of mental abilities that have hitherto remained mysterious”…


(10) “They See Where Others Hear” by Keay Davidson

Source: San Francisco Chronicle – 29 March 2001

The letter “c” is light blue, “a” evokes a sense of “weathered wood,” and “r” feels like “a sooty rag being ripped.” So wrote the novelist Vladimir Nabokov — and he wasn’t simply being poetic.

He was one of a tiny band of humans gifted with synesthesia, an unusual neurological ability to mix sensory signals from different organs…As many as one in a few hundred humans may be synesthetes. And they’re coming out of the closet and getting organized: The first national meeting of the American Synesthesia Association will be held at Princeton University on May 19…

Research on synesthesia is shedding light on brain mechanisms in general, Robertson writes in today’s issue of the journal Nature.

For example, she says, research from Australia — reported in the same issue — is helping to clarify the old scientific debate over whether one must be consciously aware of certain sensory information in order for the brain to assemble it into the coherent impressions we have of reality: say, of a rolling red ball or a passing white dove.

Compared to the relatively drab world of nonsynesthetics, some synesthetics seem to inhabit a “Yellow Submarine”-type realm where colors sing, shapes exude sensual smells, and numbers and letters illuminate their field of view..


(11) “Unlocking the Brain’s Potential”

Source: BBC News – 10 March 2001

Scientists think they have identified the part of the brain, which if switched off, can stimulate artistic genius, a BBC documentary shows.

The discovery was made after studying people with autism and dementia, but an Australian scientist believes ordinary people may one day be able to “tap in” and allow them at least a moment of genius. And in recent tests, five volunteers found their abilities were improved after the particular area of the brain was temporarily “switched off.”

Fragments of Genius explores the amazing talents of people like Stephen Wiltshire, an autistic man who has an incredible ability to draw buildings in specific and accurate detail after seeing them just once…Both Stephen and Derek Paravicini, an autistic man who is a superb jazz pianist, are savants – people with profound intellectual disabilities who have a “fragment of genius” – of whom there are thought to be no more than 25 in the world…

Dr Bruce Miller, a dementia specialist at the University of California in San Francisco, found some of his patients were developing artistic talents.

After scanning them, he found they had all had problems in the same part of the brain – the left arterial temporal lobe. He found the same part of the brain was damaged in an American savant, Dane Bottino, an 11-year-old with artistic talents.

Allan Snyder, professor of science at the Australian National University, University of Sydney and director of Centre for the Mind, has also been looking at why savants have such amazing talents, when they are so severely disabled in other ways…His theory is that because a specific part of the brain does not work properly, abilities in another area may be unlocked. And he says the savants have their gifts, because of this “malfunction” of the brain, not in spite of it…And he said if ordinary people could also find a way to get access: “Each of us could draw like a professional, do lightning fast arithmetic”…

This malfunctioning may, he believes, enable them to access certain “primitive” parts of the brain which process sound, vision and numbers.

In the BBC program, Stephen Wiltshire is taken up in a helicopter over London. Hours later, he produces a detailed and accurate drawing of a four-square mile area of the city.

The scientists believe this is possible because instead of his brain processing details of information, such as identifying a building or recognizing it, he can tune in to all the complex mental processes that lie behind that recognition, and copy them.

A team from Flinders University in Adelaide, Australia, recently used the findings of Miller and Snyder to run their own tests which found “savant skills” – memory, math and art – improved in five out of 17 volunteers, supporting Professor Snyder’s theory.

The scientists used transcranial magnetic stimulation, a technique used in the treatment of depression. It was used to switch off the frontal temporal lobe. The volunteers were tested before, during and after the treatment. The five showed improvements in calendar calculating – naming what day of the week any date in recent history was on – and drawing abilities.


(12) “Different Dispositions, Different Brains” by Siri Carpenter

Source: Monitor on Psychology – 2 February 2001

In recent years, neuroimaging research has yielded important insights into emotional phenomena ranging from depression and anxiety to autism and prejudice. In some cases, such insights have begun to spur the development of treatments for emotional problems.

For the most part, the potential role that individual personality differences might play in the emotional brain has been largely disregarded. A new study, published in the February issue of APA’s Behavioral Neuroscience (Vol. 115, No. 1), however, suggests that personality variables such as extraversion and neuroticism–known to be important to people’s emotional experience but usually assumed to be irrelevant to measures of brain functioning–deserve greater attention in the neuropsychology of emotion…

The fMRI results indicated that participants who scored high on extraversion showed greater brain reactivity to positive stimuli, relative to negative stimuli, than did participants who scored low on extraversion. For participants who scored low on extraversion, no such correlation was found.

These associations between extraversion and neural activity in response to positive images were observed in several brain regions involved in emotion, including the frontal cortex, amygdala and anterior cingulate.

Similarly, neuroticism was strongly linked to brain reactions to negative stimuli–although the pattern appeared in fewer brain regions than did the association between extraversion and responses to positive stimuli.

“Depending on personality traits, people’s brains seem to amplify some aspects of experience over others,” explains Gabrieli. “All of the participants saw positive and negative scenes, but people’s reactions were very different–one group saw the cup as being very full and the other group saw it as very empty”…


(13) “Finding Your Skills and Talents Has Mental and Physical Benefits” by Katherine Ramsland

Source: Philadelphia Inquirer – 7 April 2001

…Everyone wants to be healthier, and biologists are always testing things that affect the immune system. One study, designed by Marian Diamond at the University of California at Berkeley, indicates that the part of the brain that plans (the dorsolateral cortex) appears to communicate with the immune system.

When Diamond found that mice with a diminished dorsolateral cortex did not produce immune cells, she tested a theory on humans. Several groups of women played contract bridge – a game that requires planning, memory and strategy – while others passively listened to music. After an hour, those involved in the game showed an increase in immune-cell production (CD4 cells), but there was no such benefit for the music listeners.

Diamond surmised that activities that stimulate the planning brain may also strengthen the immune system. “From our preliminary results showing that the game of bridge can increase CD4 cells,” she says, “our research supports the possibility that taking control over your life can enhance your physical health.”

To plan effectively, we need a sense of purpose, such as that touted in the 1980s by folklorist Joseph Campbell. He urged people to direct their lives toward the “special track” that was waiting for them. Once found, then “the life that you should be living is the one you are living.” In other words, seek your bliss.

By bliss Campbell meant that each person has skills and talents that collectively move him or her toward authentic self-expression. As with Billy Elliot, who had to dance, even if it meant taking a ballet class with girls, bliss is our natural direction; it inspires the highest caliber of creativity and performance…Therapist Pelli Wheaton believes that less than 10 percent of the American people are being their own true selves, because it takes courage to break patterns that block us. Those who live authentically, she observes, “radiate joy”…

We can think of bliss as both the stimulus and the goal that gets us through an obstacle course known as life. Bliss is not fate. It’s more the idea that our style, background and personality best match a particular vocation or avocation…Because bliss is inner-driven, we know when “this is it!” As in a challenging game, we have to strategize our way around life’s obstacles, but bliss is our driving force. A side benefit is the boost to our immune systems.

In short, finding our bliss gives us both mental and physical advantages, and when we offer the world the best we have, we help make it a better place to live.