Dana Foundation: Brain in the News, February 2005, Vol. 12 No. 2. “Teens’ Brains Not Fully Wired for Reason,” by Gabrielle Glaser, The Oregonian. In an eye-opening discussion, Alexander Stevens (Ass.t Professor at the Oregon Health and Science University) explains that a teenage brain is a “work in progress.” There was a belief in the past that a teen brain processed information much the same as does an adult. But recent research is finding that teens lack neural circuitry in the frontal lobe necessary for decision-making. And the circuitry is not in place until they are in their early 20s. The last part of the brain to mature is the frontal cortex, the executive brain – responsible for planning, problem solving and reason. Although teens are notorious for feelings of immortality, it may be that teens actually do not consider negative outcomes. Teens, particularly up to age 15, have great difficulty controlling involuntary responses. Also, the McLean Hospital in Massachusetts found that teens rely on the amygdala, the reaction/emotional center of the brain, to interpret sensitive emotional information. Unlike adults who read facial expressions and body language with 100% accuracy, teens misidentify expressions of others quite routinely. This is likely because of the slow maturation of the frontal cortex.

Nature Reviews Neuroscience, September 2004, Volume 5, No. 9. “Improving language and literacy is a matter of time,” Paula Tallal. P. 721. In a discussion of dyslexia, evidence is put forth that dyslexia is likely the result from a deficit in auditory processing. Findings that relate to this conclusion are described, as is an intervention strategy to tackle literacy and language problems.

Dana Foundation: Brain in the News, February 2005, Vol. 12 No. 2. “Addicts May Be Wired Not to Stop,” by Janelle Miles, The Courier Mail, Queensland Australia.. A fascinating discussion of new perspective regarding addiction to drugs and gambling, which contradicts the assumption held for years that addiction comes because pleasure and reward associated with it are too great to resist. Neuropsychologist Murat Yucel of the University of Melbourne claims that addicts might actually have a dysfunction in their brain frontal cortex, which disallows control – even with a realization of the devastating consequences of their actions. Two areas of the frontal cortex, the anterior cingulated cortex and the orbitofrontal cortex, were activated as people weighed up the pros and cons of a particular action. In addicts, however, studies show reduced blood flow to those same areas. The regions involved comprise 5-10% of a person’s brain. In research involving 18-50 year old addicts and non-addicts, there is a hope to measure the blood flow as well as chemical and anatomical differences between the brains of addicts and non-addicts in the future to determine the validity of the hypothesis.

Dana Foundation: Brain Work, January-February 2005, Vol. 15 No. 1 Tourette Syndrome: A Neural Circuit Gone Awry by Rabiya S. Tuma. This article explores the misconceptions and new understanding regarding Tourette syndrome (TS). Whereas some neurological disorders involve the disfunction of single brain nerve cells, TS involves an entire brain circuit. Like many disorders, there is a continuum of symptoms, as well as variations in severity. And too, some 1/3 of patients outgrow symptoms by age 20 while others never do. But use of magnetic resonance imaging has found that victims of the disorder have a 5% decrease in the volume of the caudate nucleus, a portion of the basal ganglia. There is work now to predict which patients will continue to have symptoms throughout their lives, as there is some correlation between the decreased caudate size and the persistence of problems. Because of research using monkeys whose brains are stimulated with electrodes into the striatum of the basal ganglia circuit, there is early evidence that the primary defect in the basal ganglia causing particular movements or behavior common to TS patients may occur in the striatum. This first step, understanding Tourette syndrome, actually is key to finding a cure.

Dana Foundation: Brain Work, January-February 2005, Vol. 15 No. 1 “Parenting Matters: Your Genes Prove It,” by Brenda Patoine. The long held belief that parenting influences the kind of adult a child becomes – and although there is much research that documents the effect of environmental, social and nurturing styles on development, there is increasing evidence that early experience is relevant to human development on the molecular as well as brain levels. The reaction to stress and fearfulness in adult rats correlates to mothering styles they experiences as infants, and the article details the investigation as to why.

Dana Foundation: Brain Work, January-February 2005, Vol. 15 No. 1. “The Neurobiology of Economic Decisions, “Risk and Reward Systems in Adolescents,” by Rabiya S. Tuma. Even though the cognitive abilities of teens compares to those of adults, teens are more apt to take high risk whereas adults are not. Gregory Berns of Emory University School of Medicine in Atlanta believes that the immaturity of the reward system in a young person’s brain causes over-activity in response to novelty. In studying teens aged 13-17 and adults aged 30-50, a fMRI was used to watch the activity in the striatum, a region of the basal ganglia involved in assessing reward. The research showed a difference in how teens processed reward stimuli in comparison to adults, and that they appeared “hypersensitive to novel experiences.” Berns says, “…it seems that the dopamine system peaks in adolescence, and that the brain is novelty-seeking.”

Dana Foundation: Brain Work, January-February 2005, Vol. 15 No. 1. “News from the Frontier, “Fats and Learning.” Animal studies are illuminating the effects of high-fat diets on learning and memory. Diets high in fat or fat and sugar were not only new-memory impaired, but vulnerable to stress induced cognitive dysfunction. According to this article, if the results can translate to humans, the intake of empty calories may not only negatively affect acquisition of new memory but “…increase resistance to age-and stress-related cognitive impairment.” The work of John Morley and others at St. Louis University found that obese rodents fed a high fat diet had impaired cognitive performance. When exposed to a state similar to sleep apnea, the results were disastrous for the brain of the mice. More mistakes on working memory tasks, learning and memory performances were substantially poorer.

Dana Foundation: Brain in the News, July 2004, Vol. 11 No. 7. “Brain is Atypical in Autistic Boys,” by Dorsey Griffith of the Sacramento Bee. Studies done at UC Davis MIND Institute has found that two brain regions are larger in autistic boys than in normal male brains. The amygdala and the hippocampus, both fundamental in memory and emotion, appear to develop to quicker and earlier than in the brains of normal male children. This, regardless of IQ, was manifested in the amygdala that increased in size as much as 17% larger than normal brains initially (since the amygdala is instrumental in fear, it may account for the increased fearfulness of autistic children), but then did not continue to change as time went on. In normal development, the amygdala increases in size about 40% - but over an extended period of time. The amydala is also larger in children with Asperger syndrom, but to a lesser degree.

Dana Foundation: Brain in the News, August 2004, Vol. 11 No. 8. “Autism: A Problem of Brain Connections,” by Byron Spice of the Pittsburgh Post-Gazette. In a fascinating discussion of research related to autism, the research published in the British journal BRAIN suggests that different brain regions of autism patients do not work in a coordinated manner as normal brains do, particularly necessary for high-level thinking. Seemingly, there exists either a lack or a surplus of connections results in inefficiency of communication - which may help explain the disordered thinking of an autistic patient. More research regarding interconnectivity of the brain may result from this work. Because the variations in symptoms of autistic patients vary in extremes, it has been difficult to research the disorder. Usually, however, autistic patients have a good understanding of individual words – but tremendous difficulty manipulating them within a context. One definite observation is the increase activation of the Wernicke region in autistic patients and less in the Broca area than normal brains. The former aids in word recognition, and the latter allows for word understanding (semantics). Synchronization of activity was lower in the autistic patient however, as observed using fMRI.

Dana Foundation: Brain in the News, July 2004, Vol. 11 No. 7. “This is your Brain on Math,” by Geoff Koch of the Dallas Morning News. In what has become an increasingly controversial topic, Mr. Koch explores the apparent hard-wired circuitry in both animals and humans for numeracy and math skills. Although science has long know that young children and animals share the same basic math skills, it is becoming clearer that the skills are entrenched in brain circuitry acquired through evolution. There is also a discussion of brains that are “math gifted,” and why math-giftedness appears six to 13 times as often in males than females. Theorizing, Dr. Michael O’Boyle from the University of Melbourne (Australia) in the journal Neuropsychology suggests that it may be due to prenatal exposure to testosterone, which selectively benefits the right hemisphere of the brain.

Science News, February 19, 2005,Vol. 167 No.8 “Math minus Grammar,” by B. Bower. This article highlights three British men who sustained left brain damage that left them without ability to speak or understand language, yet with full capacity to grasp mathematics. Although there is no way to determine whether language is needed to develop number sense, it does again underscore the argument that language and math follow “…different mental and neural paths.” According to Elizabeth M. Brannon of Duke University, it ”provides additional evidence that mathematics and language are functionally and neuroanatomically independent.” Although there is a belief among some that the evolution of language grammar provided a basis for mathematical rules, there is no evidence from research to date that knowledge of mathematical rules by humans of nonhuman animals exists.

U.S. News and World Report, “Mysteries of the Teen Years.” May 10, 2005 special edition. This is a “must have” edition for parents, focusing on four general areas of discussion: behavior, health, culture, and voices. Although much is observation and opinion and reads like a magazine article, there is a fair amount of research that increases an understanding of today’s teens. Topics of special interest include alcohol, depression, risk taking, current teen culture, and the importance of sports.

National Geographic, March 2005, “What’s in Your Mind” is an extensive section with quality information on a wide range of topics concerning mind and brain (“The mind is what the brain does”). They include: Evolution of perceptions of the mind-brain link, observations from brain surgery, perception and vision, development of sophisticated brain wiring and extensive memory, perception of emotion, innate vs acquired fears and the amygdala, autistic genius, perfect pitch, infant cognitive skill, malleability of the brain, hypergraphia, and spiritualism.

“Informal Learning for Children,” February 1, 2005, by Greer C. Bautz. http://gseweb.harvard.edu/news/feature/blatt02012005.html
This resource is actuallyl an interview of the Harvard Graduate School of Education’s Technology in Education master’s program, Joseph Blatt. He has spent much of his career studying the effects of media and technology on the learning, development and civic behavior of young people. He collaborates with Sesame Workshop, the creators of Sesame Street. His focus is on bettering the chances for the electronic media to benefit children educationally. Because children average more than 40 hours per week in front of screens, Blatt says there has been a shift in the learning of young people. First, there is an increased emphasis on visual and sound communication, imagery and demonstration. These replace the importance of description, in the past. He believes this shift will force learning to become more concrete and egalitarian. Also, he sees the differences in content between youth and adults of the past diminishing. He also believes that will force children to develop skills in constructing meaning from unfiltered information, with which they are continually bombarded. It will require from parents and teachers, however, much guidance and training in assessing sources, understanding manipulation, and developing the ability to synthesize.

Science News, April 2, 2005. Vol. 167, No.14“Still Hungry,” by Janet Raloff. This article explores the role of the hormone, ghrelin, which causes some humans to feel unsated even after ingesting many calories. It explores the eating habits and the obesity problems facing us today, but also points to factors including body weight, food choices and lack of sleep in our society that affect feelings of hunger. It is becoming apparent that there is an array of lifestyle and diet factors that modify the production of ghrelin in a body, and thus affects hunger and the tendency to over – or under – eat. Ghrelin triggers appetite, which is moderated by appetite suppressors insulin (pancreas) and leptin (fat cells are the source). It has been found that fat, calorie for calorie, is less effective at suppressing ghrelin than other types of food. While the intake of sugar and protein prompt the drop of ghrelin concentration, fat causes a much slower drop. Low fat diets suppress hunger hormones better than fat. Another observation is that fructose, the primary sugar in fruits and soft drinks is not as efficient in lowering ghrelin signals as glucose… Also, hunger and satiety signals don’t function well in heavy weight humans, so that compared to non-obese people, “the heavier humans remain hungry longer and don’t feel full as quickly.”

Science News, November 13, 2004,Vol. 166 No.“Assault on Autism,” by Diana Parsell. In an article that studies the roots of autism, there is a close look at environmental effects. Because difficulties can occur at so many points in early human development, this is difficult. But autism may in fact result in part from environmental influences in utero that disrupt normal early development. Hormones, stress, viral infections of the mother, and toxic exposures may each cause the human nervous and immune systems to undergo remodeling. Research finds that children with mutations in genes that encode enzymes are at higher risk of damage from such environmental influences.

Time Magazine, “The Math Myth: The real truth about Women’s Brains and the Gender Gap in Science,” by Amanda Ripley. March 7, 2005. In a series of articles, Time looks at research and common perceptions regarding gender performance in science and math areas. Worth reading, the articles leave more questions than they answer.
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