Nature Reviews/Neuroscience Volume 3, September 2002, The Cognitive Neuroscience of Sleep: Neuronal Systems, Consciousness and Learning, by J. Allan Hobson and Edward F. Pace-Schott, pp. 679-691. In work done with REM and Non REM sleep, the regional activation patterns and neurochemistry of REM sleep effects the emotional component of a conscious experience in a dream and the subsequent unconscious changes in memory. “The psychological features of dreaming are determined by the specific regional activation patterns and neurochemistry of sleep.” This lengthy article, worthy of reading, speaks of the brains activity during waking that allows behaviors that are characterized by interaction with the outside world. The brain captures important information from the interaction, and during NREM sleep the brain goes “off-line.” This allows “stereotyped endogenous activation” to be recreated in the forebrain, allowing recent input of information from conscious experience to one repeated and revisited in a way that promotes alterations associated with the formation and consolidation of memory. During REM sleep, “the brain is reactivated by the micro-chemistry and regional activation patterns are markedly different from those of waking and NREM sleep.” The memories consolidated in the cortex, stored during the NREM sleep by repetitive revisitation of input circuits via the hippocampus, are integrated with OTHER previously stored memories during REM sleep. So “…dreaming is the conscious experience of hyper-associative brain activity that is maximal in REM sleep.”

Science News, September 7, 2002, Vol. 162, p.152. Missed ZZZ’s, More Disease? By Kristin Cobb. Although much research of late has focused on the importance of sleep and it potential effects on performance, obesity and well-being, this article out of SUNY/Buffalo reports a possible connection between lack of sleep and obesity. In sleep deprived humans, cravings for high sugar and high starch food is common – although not cravings for fruits or vegetables. “Partial sleep deprivation appears to lead to hormonal and metabolic changes, resulting in increased concentrations of stress hormones and altered hormonal response to stressful situations… .”

At Penn State University College of Medicine (Hershey), 25 young and healthy adults were deprived of 2 hours of sleep per night for one week, quite typical for modest sleep deprivation common among Americans. After a week of sleeping only 6 hours per night, test volunteers had increased blood concentrations of cytokines – which causes fatigue. It is cytokines which, when over abundant, cause a drop in alertness and performance. Among the male volunteers, cytokine TNF-a was elevated, reflecting a likelihood of low-grade inflammation which can lead to damaged arteries and subsequent vessel narrowing. High blood pressure, heart disease and stroke can result from chronic low-grade inflammation – and there are associations between inflammation and insulin resistance, obesity and diabetes.

Washington Post, www.washingtonpost.com/wp-dyn/articles/A28464-2002Jul31.html
Study: New Drug May Aid Autistic Children: Schizophrenia Medicine Found to Control Outbursts Associated with Disorder, by Shankar Vedantam. Thursday, August 1, 2002, page A09. New studies show autistic children whose behavior is characterized by tantrums, aggression and self-injurious behavior may benefit from an antipsychotic medicine approved to treat schizophrenia in adults.

Risperdal, not yet approved by the FDA for this “off-label”use, appears to reduce behaviors such as uncontrollable bursts of anger, frustration, violence, biting, scratching and banging heads. Such outbursts make functioning in intense learning structures nearly impossible – and it is from learning structures that autistic children can acquire knowledge and routine social skills to function successfully. (Remedial and rehabilitative efforts for these children make it possible for them to attend school and carry out such routine personal tasks as dressing.)

Lawrence Scahill, associate professor in child psychiatry and nursing at Yale, reports the result of his work in the NEW ENGLAND JOURNAL OF MEDICINE. It is the first comprehensive evaluation to support the same findings from small studies done by pharmaceutical companies. This study was paid for by NIMH, and tracked the use of Risperdal on 101 children ages 5 to 17. The autistic children were given either the Risperdal or a placebo for eight weeks, then tracked for behavior six months.

Although the core symptoms of autism were not significantly impacted by the use of Risperdal, the serious behavior problems were effectively reduced – such as aggression, self-injury and tantrums.

USA Today, www.usatoday.com/usatonline/20020802/4329656s.htm Cuts in class size fail to bolster learning Although the interest in reduction of class size to improve achievement has increased in the past decade, inspiring nearly half of American states to launch programs to reduce class size, new research casts doubt on the merit of such plans.

A San Francisco think tank released a study ast month that undermines the California billion dollar per year effort to create smaller classrooms, saying that the impact on learning is not sufficient to warrant such expenditures. The report states that the variable most important in student learning was teacher quality, not class size. In California, the need for additional teachers t man smaller classes infused the system with less effective teachers, so that lower quality teaching negated nearly all benefits from reduced class size.

Improvement in teaching skills may be the necessary thrust for improving student achievement: “Teacher quality trumps class size every time.”

U. S, News and World Report August 12, 2002, p. 45. Genes + abuse = trouble By Nancy Shute
Children of abuse often grow up to become violent adults; but a sizeable percentage of them do not. The difference may be due to a “genetic variation” that enables some abused youngsters to develop resiliency. This work was reported in the August SCIENCE.

In tracking male children born in 1971 in New Zealand who had all been mistreated, beaten or molested it was found that 85% of the boys who had a gene that reduced the amount of a particular enzyme, MAOA, had committed violent crimes or gotten into trouble by age 26. MAOA limits the availability of serotonin (and other brain chemicals). Proper serotonin levels are known to limit impulsivity and aggression.

Those abused children who did not grow into violent adults had a gene that allowed high levels of MAOA (thereby enabling proper amounts of serotonin in the brain). The children never abused but possessing the gene that reduces MAOA exhibit no more violence than those with lots of MAOA. The work highlights the importance of the environment in manifesting the pre-dispositions of the genes, making clear the importance of gene-environment interactions. Early trauma may indeed alter brain chemistry for a lifetime.

Science News, August 3, 2002, Vol. 162, p.68 Resilient DNA In a related article (see above), Seth D. Pollak of the University of Wisconsin-Madison reports that “…females in the same study showed a significant but less dramatic effect of the MAOA gene on the linkage between childhood maltreatment and later antisocial behavior.” It may be because females possess two X chromosomes and are thus more apt to inherit at least one MAOA gene. Monoamine oxidase A, or MAOA, is a gene situated on the X chromosome.

In males with low activity MAOA gene, the antisocial behavior developing included persistent fighting, bullying, stealing, and law breaking – with no signs of remorse.

The MAOA gene yields an enzyme that lowers brain concentrations of chemical messengers such as norepinephrine, serotonin and dopamine. In the 442 young males in New Zealand who had been studied from age three, 36% by age 11 had experienced some form of abuse, including physical, sexual and absence of consistent caregivers. 12% of the males that were maltreated possessed the low-activity MAOA gene, but they accounted for nearly half of all later convictions for violent crimes.

Science News, July 27, 2002, Vol. 162. P. 53 Staying Alive with Attitude: Beliefs about aging sway seniors’ survival For people over age 50, those with positive views about themselves live an average of 7 1/2 years longer than those negative about their senior status. The effect of the positive attitude impacts life span even more than the years added to life due to low blood pressure, cholesterol, moderate body weight, and avoidance of smoking. This work comes from Becca R. Levy of Yale, psychologist reporting work in the August JOURNAL OF PERSONALITY AND SOCIAL PSYCHOLOGY. The differences in the will to live may explain a link between “…survival and self-perceptions of aging.” The occupations of people involved in no way affected the results.

The link between attitude toward aging and survival may also be reflective of physiological reactions to stress by those with negative views.

Science News, August 10, 2002, Vol. 162. P. 94 Speech loses beat in dyslexia Children with dyslexia often have spelling and reading problems, primarily because they do not detect the critical rhythm of spoken words. This comes from work out of the University College London and work headed up by a team led by Usha Goswami.

The sound cue, requiring 1/10 to 1/5 of a second, allows the human brain to note the transition from consonant sounds to vowel segments in speech. The inability to detect the transition makes it difficult to sound out words, and hence to read properly Very difficult might be detecting nuances of differences in rhyming words or similar sounding words, such as sweet, street and seat.

24 children with dyslexia and 49 normal readers were tested, all age 9 years. Work reported in PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES notes that only dyslexics had difficulty “…discerning the beat in continuous sounds containing sudden rises and falls in loudness, such as speech transitions as “sw-eet.”

Discover, September 2002, Are You Hungry? p 23 – 24. This article explores the problems of Prader-Willi syndrome, which slows metabolism and increases appetite to cause overt obesity in the 20,000 victims suffering from it. Positive signals from the mouth release dopamine and opioids in the brain to create a sense of pleasure, with normal human body reaction releasing hormones to slow the appetite. The pleasurable reactions are strong: as eating preferred food releases dopamine in the same regions of the human brain as does heroin. In fact, much recent appetite research focuses on the brain’s pleasure centers and the neuro-chemicals involved. The breakdown in the Prader-Willi victims is in the hypothalamic mediation of hormone responses to eating, and the control of the hypothalamus of metabolic systems. The metabolism involves heart rate, body temperature, and growth

U.S. News and World Report, August 19, 2002 p 50 The gene that wouldn’t sit still by Emily Sohn. Researchers have linked a single gene variant to many ADHD cases, tracking its effect on humans all over the world. In work published in PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES two years ago, a study found that children with the 7R form of DRD4 might be more apt to be diagnosed ADHD than those without the variant. DRD4 is one of five genes that code receptor proteins to allow brain cells to pick up the brain chemical called dopamine. Dopamine influences human motivation and behavior. DRD4 is one of the most variable of the human genes, perhaps contributing to differences in behavior or personality from person to person. One of its eleven forms, called the 7-repeat variation (7R) appears in half of the children with ADHD. Its frequency in those without the disorder, however, is just 20%. It is the most solid link between any behavior or behavior disorder and a gene. This comes from University of Toronto psychiatrist James Kennedy, an early researcher in the study of DRD4. Full understanding of DRD4 will be essential before any of the newer interest in this gene’s indications for children and adults with ADHD, but it is possible that medication to calm children may not be optimum: perhaps a refunneling of such people into careers full of adventures, or careers demanding risk and high energy where those with the 7R variant seem to excel.
Discover, October 2002, Vol. 23, No. 10, pp. 34-40. The Blank Slate, by Steven Pinker. This article does a fine job explaining the interplay of genetics and environment in human behavior, examining it in light of the cultural tendency to favor the ‘tabula rasa’ theory. Such a belief promotes the idea that human social frailties, human shortfalls can be eliminated through proper manipulation of environmental conditions. This, according to Pinker, violates the truth about human nature and the real information from research. A must-read, this article clearly states the importance of foundational genetics while respecting the role played by experience in manifesting behavior.

The work out of U of California San Diego earlier this year, reported by Daniel F. Kripke, claimed that anything “more than 7 hours is optional sleep, and that people sleeping more than 7.5 hours a sleep per night were more likely to die,” contradicts this latest work. However, Vgontzas of Penn State refutes Kripke’s work, claiming that “…underlying depression and sickness probably explain the apparent association between sleeping 8 or more hours and increased mortality…”

Science News, September 14, 2002, Vol. 162, p.163. Smoking Gun? Mouse tests link nicotine to crib death The role nicotine plays in mimicking the brain chemical necessary for arousing people from sleep may increase the risk of SIDS in babies born of women who smoked during pregnancy.

SIDS babies do not struggle to breath when deprived of oxygen, leading to death. The normal human alert system would signal a need to breath – made possible when acetylcholine is triggered to bind to receptor molecules on cell surfaces as oxygen levels in the blood drop to dangerous levels. That causes a healthy system to arouse the respiratory system to breath, whereas nicotine dampens the arousal reaction. Since nicotine binds to the receptor sites that acetylcholine needs to do its job in the arousal process, the arousal reaction is significantly blunted. The work done at Pasteur Institute in Paris may explain the relationship between smoking and SIIDS.

Science News, August 31, 2002, Vol. 162, p.34. Gift of Gab: Speech insights spark statistical static New research out of SCIENCE magazine reports that adults can spot patterns in language syllables, even when they are nonsense – but that rules of language construction may not be innate.

It is one of the early findings that support the theory that humans are born with a “…brain-based grasp of grammar,” including the logic of word construction. It is the pauses in spoken word (even nonsense or foreign languages) that enable listeners to understand rules for building words. The rhythm and intonations of natural speech are sought by the human brain.

Discover, October 2002, Vol. 23, No. 10, pp. 63-67. Free Radical, by Karen Wright Bruce Ames work is highlighted in this fascinating summary of his theory regarding the role of free radicals in the aging process. Ames has worked in the area of dietary supplements for rejuvenating physically and mentally with a research group at Berkeley and in Children’s Hospital Oakland. Through work with rats, mental processing and physical aging characteristics have been bettered. It is Ames’ belief that the same can eventually be done with humans.

Research has proven that most aging and human anomolies occur as a result of mutations, causing damaging genes. Carcinogens for instance, stress the body and possibly create genetic damage leading to cancer. The fact is that half of all chemicals, natural or synthetic, become carcinogenic if they are delivere3d in high doses – so over concern regarding the presence of trace amounts of such substances is unrealistically feared. Ames believes that a proactive lifestyle, mainly one that eliminates such behaviors such as poor eating habits, smoking, and excessive drinking – coupled with good nutrition – can avoid damaged genes, thereby extending the healthy life span of a human.

The article centers on the role of free radicals in the degeneration of human cells. Free radicals are molecules that destroy the interiors of cells, because they contain unpaired electron that bonds with other healthy molecules, thereby stripping the healthy molecules of electrons that they need. Resulting is broken chromosomes, crippled enzymes and compromised cell membranes. The process whereby electrons are “stolen” from healthy human cells is oxidation, and it can even break strands of DNA.

Although the damage is repaired by the human body, natural error causes mistakes (mutations). These genetic mutations predisposes a human to disease and maladies – perhaps even cancer. Research has found that the older a rodent is, the more oxidation in tissue there is – thus, the greater the chance for errors or mutations. Much of the difference in presence of free radicals in varying aged rodents centers in the cells’ power centers – mitochondria. Ames discovery of a supplement to improve the functioning of mitochondria appeared to better the biochemistry and behavior of rats. However, although mitochondria were functioning more efficiently than their untreated counterparts, free radical production was also elevated – presenting the possibility of speeded mutation and deterioration.

The diet of the rodents was then changed with the addition of an agent to neutralize oxidants. Lipoic, a mitochondrial antioxident, positively impacted that. As a result, not only did the mitochondria function improve, the rat memory and function in improved dramatically. Current research is measuring whether life span is simultaneously lengthened.

Human diets may also yield improvements in cell functioning and in brain functioning. Alcar (the supplement that improves structure and functioning of the mitochondria) and Lipoic acid may be a change worth tracking and studying as to the effects on human well-being and functioning. Ames believes that B vitamin therapy may be a way to begin such a pathway in improving nutrition. But he also believes that the future may allow for DNA screening to assess the oxidative damage to a person’s genes, and thus to determine a customized dietary intervention to counter them. But for now, vitamins are the single best approach, according to Ames.

Nature, Volume 418, August 29, 2002, p. 929-930 The molecules of forgetfulness, by Alcino J. Silva and Sheena A. Josselyn. Since not everything that we learn has use, brains prevent overburdening via a mechanism to forget. Although cognitive processing includes techniques for over-expression of genes, deletion or modification of genes in rodents, it is now becoming clearer how memory is regulated by molecules (protein phosphatases and kinases) with opposing functions. Each of the molecules has a role in either removing or adding phosphate groups on targeted proteins to alter their respective properties.

A natural inhibitor blocks (PPI) neuronal activity (forming of memory) and researchers have been able to alter the expression of the inhibitor in mice. It was learned that massed training triggers more inhibitor activity than distributed training, thus making distributed (or shorter segments of training versus one long, equal length training session) more efficient for planting new memory (hence, learning). Blocking the inhibitor during training accelerates learning, and massed training results in suppressing both short term and long term processes involved in learning and memory formation. It appears that in studies involving mice, memory formation, memory decline, and suppression of memory can be altered through changes in neuronal communication brought on by signaling molecules at the synapses.

Science News, August 24, 2002, Vol. 162, p.118. All about me: Left brain may shine spotlight on self Past research has indicated that face recognition is processed on the right hemisphere of the brain’s cerebral cortex. Identification of one’s own face, however, may be processed differently. In work reported in Nature Neuroscience, coming out of Dartmouth College in New Hampshire, left-brain networks hold primary responsibility for memories and knowledge about oneself, including visual distinctions Personal recognition “…allows for other types of complex thought, such as empathy and introspection.”
Science News, August 24, 2002, Vol. 162, p.126. Tracking signs of memory loss Brain scans can track a compound to highlight the plaques present in Alzheimer’s disease, before the autopsies that heretofore were the only real indicators of the disease. Beta-amyloid plaques that clog the brain can now be detected in early stages, allowing victims the therapies best able to thwart the disease’s progression.

The radioactive molecule that crosses from blood into the brain, binding to plaques and therefore trackable through brain scans in seemingly healthy patients (prior to the manifestation of the disease) are safe for use in animals. The procedure has been tested in humans in Uppsala University in Sweden, with impressive results. The findings were shared in July in Stockholm at the International Conference for Alzheimer’s Disease and Related Disorders.

Nature, Volume 418, August 15, 2002, p. 734-736 Positive feedback from coffee
By Jean-Marie Vaugeois Caffeine likely blocks two proteins, the A1 and A2A receptors that control voluntary movements. As a result, the receptors no longer detect the neuromodulator adenosine, which “…results in a long-lasting decrease in the activity of inhibitory neurons…,” and hence there is more movement.

By blocking the receptors, caffeine eventually blocks the action of the protein receptors that reduce motor activity – working through the striatum, a region of the brain that controls motor activity. Thus, our nerve cells “wake up.”

Adenosine activates and turns on the genes by activating the A2A receptor. Also, DARPP-32, a protein, prolongs and intensifies the effects of low doses of caffeine, but higher doses produce a long lasting blockage of A2A receptors, so that no feedback loop is needed to inhibit the enzyme. The DARFF-32 protein extends the effects of caffeine. There is speculation that caffeine might eventually help protect against nerve degeneration as that which occurs in Parkinson’s disease. A2A blockers are potential treatments for such a malady, afflicting neurons involved in movement.

Nature Review/Neuroscience, Volume 3, August 2002, p. 589 Now you see it… Although traditional thinking has assumed that only primitive visual features, such as color or orientation, can be picked out of a visual field when one is not “paying attention.” A new study reported in PROCEDURES NATIONAL ACADEMY OF SCIENCE, 20 June 2002, reports that even two images on either side of a focal point could be categorized rapidly and in parallel. Whether that is due to separate processing by individual brain hemispheres or not is unclear. Also, complex sets of visual features can be detected and categorized even when a subject does not devote full attention to it: i.e., it is not the focal point of concentration.

This preliminary work might indicate that the “…gating of visual information by attention is much less simple than we thought, and that ‘early’ processing can include processes that occur at high levels of the visual system.” It could also indicate that classroom distractions might be far more prevalent and have greater impact on students than previously thought.

Nature Review/Neuroscience, Volume 3, August 2002, p. 617-626 Neuroscience of Attention-Deficit/Hyperactivity Disorder: The Search for Endophenotypes, by F. Castellanos and R. Tannock This lengthy article deals with the controversial condition of ADHD, which has been handled heretofore either descriptively and atheoretically. There is discussion of quantifiable “intermediate constructs” or endophenotypes, which the authors review selectively to begin the uncovering of causes of the malady, rather than just descriptions of it. The three selected endophenotypes include: deficits in temporal processing, deficits in working memory, and shortened delay gradients that are tied to reward-related circuitry. The article also includes a discussion on the relationship of nicotine use by a mother and later development of ADHD symptoms. Diagnostic criteria are included in chart form, and locomotor hyperactivity is discussed in relationship to dopamine.