All ears are not created equal, a new report suggests, even two on the same head. Results published in the current issue of the journal Science indicate that infants process sounds differently through their left ears than they do through the right. The findings could have implications for treating hearing impairments. It has long been known that different parts of the brain process different kinds of sounds. The left hemisphere, for example, deciphers rapidly changing sounds such as speech, whereas the right hemisphere dominates the processing of tones and musical sounds. But, explains Yvonne Sininger of the David Geffen School of Medicine at the University of California at Los Angeles, “no one has looked closely at the role played by the ear in processing auditory signals.” Sininger and co-author Barbara Cone-Wesson of the University of Arizona spent six years evaluating the hearing of newborns before they left the hospital. More than 3,000 babies had their hearing tested using a tiny probe (see image) that measures how much certain sounds are amplified by parts of the ear. The researchers tested the children's hearing using two types of noises: sustained tones and a set of rapid clicks, which were timed to imitate speech. “We were intrigued to discover that the clicks triggered more amplification in the baby's right ear, while the tones induced more amplification in the baby's left ear,” Sininger remarks. “This parallels how the brain processes speech and music, except the sides are reversed due to the brain's cross connections.” According to the authors the results indicate that auditory processing begins in the ear, before sounds reach the brain, and could help to improve therapies for hearing-impaired patients. Notes Cone-Wesson: “Sound processing programs for hearing devices could be individualized for each ear to provide the best conditions for hearing speech or music.” --Sarah Graham © 1996-2004 Scientific American, Inc.

Keyword: Hearing; Laterality
Link ID: 6105 - Posted: 06.24.2010

By GARDINER HARRIS When the Food and Drug Administration opens an advisory committee hearing tomorrow into the safety of antidepressants, several committee members will push for tougher warnings saying that a child or teenager given the drugs can become suicidal in the first weeks of therapy, they said in interviews. "I want the warning strengthened," said Dr. Richard Gorman, a member of the committee and a pediatrician from Ellicott City, Md. "I would also like the pharmaceutical companies to send out letters to doctors saying that, in kids, this stuff doesn't work." Dr. James McGough, another committee member and a professor of clinical psychiatry at the University of California, Los Angeles, also said he wanted stronger warnings. For more than a year, agency officials have struggled to find the appropriate balance between warning patients about the possible suicide risk of antidepressants and reassuring those patients that drug therapy can be an effective and safe remedy. Copyright 2004 The New York Times Company

Keyword: Depression; Development of the Brain
Link ID: 6104 - Posted: 09.13.2004

Hi-tech images of the retina could allow earlier diagnosis of eye diseases, researchers suggest. The spectral imaging technique enables doctors to spot changes in blood vessels in the eye. The Heriot Watt University researchers who developed it said it could help detect glaucoma, diabetic retinopathy and age-related macular degeneration. Details of the imaging technique were presented to the Institute of Physics conference in Glasgow. It is estimated that by 2020, there will be 200m visually impaired people in the world, but 80% could be prevented or treated. The spectral imaging technique uses a standard ophthalmoscope which has been adapted so it can take a series of images of the retina at specific wavelengths. It shows how oxygenated the blood flowing out of the retina is. The higher the oxygenation level, the less healthy the retina. Spotting this early allows doctors to then look at what could be causing the problem. The images are captured by a sophisticated digital camera. Image processing corrects for the movements of the eye while the pictures are being taken, and a large set of images are combined to provide the clearest depiction possible. (C)BBC

Keyword: Vision
Link ID: 6103 - Posted: 09.13.2004

Gasotransmitters open a window on biology and drug development By Mark Greener High levels of carbon monoxide interfere with cellular respiration and pollute the environment. Hydrogen sulfide (H2S), another chemical asphyxiant, paralyzes the sense of smell and at lower levels produces the rotten-egg stink prized by children using their first chemistry sets. But even the noxious to the downright deadly can have a subtler side: at minute concentrations, both gases transmit biological signals between cells. Over the past 20 years or so, research into the growing array of so-called gasotransmitters, endogenously produced gaseous transmitters like nitric oxide (NO), CO, and H2S, has fundamentally altered classic views of intercellular signaling.1 They act in systems as varied as gastrointestinal, circulatory, and nervous.2 Gasotransmitters are not stored in vesicles; rather, exquisitely regulated biosynthetic enzymes are activated when signaling is initiated. Moreover, while the proteins that sense the gases are diverse, the architecture seems highly conserved. The research offers a fresh perspective on processes as diverse as neural control, blood vessel diameter, and embryonic development. It also raises numerous new therapeutic and diagnostic opportunities. In fact, physicians already prescribe drugs modulating gasotransmitters to manage erectile dysfunction and angina. © 2004, The Scientist LLC,

Keyword: Learning & Memory
Link ID: 6102 - Posted: 06.24.2010

By PAUL BLOOM New Haven — What people think about many of the big issues that will be discussed in the next two months - like gay marriage, stem-cell research and the role of religion in public life - is intimately related to their views on human nature. And while there may be differences between Republicans and Democrats, one fundamental assumption is accepted by almost everyone. This would be reassuring - if science didn't tell us that this assumption is mistaken. People see bodies and souls as separate; we are common-sense dualists. The President's Council on Bioethics expressed this belief system with considerable eloquence in its December 2003 report "Being Human'': "We have both corporeal and noncorporeal aspects. We are embodied spirits and inspirited bodies (or, if you will, embodied minds and minded bodies)." Our dualism makes it possible for us to appreciate stories where people are liberated from their bodies. In the movie "13 Going on 30,'' a teenager wakes up as Jennifer Garner, just as a 12-year-old was once transformed into Tom Hanks in "Big.'' Characters can trade bodies, as in "Freaky Friday,'' or battle for control of a single body, as when Steve Martin and Lily Tomlin fight it out in "All of Me.'' Body-hopping is not a Hollywood invention. Franz Kafka tells of a man who wakes up one morning as a gigantic insect. Homer, writing hundreds of years before the birth of Christ, describes how the companions of Odysseus were transformed into pigs - but their minds were unchanged, and so they wept. Children easily understand stories in which the frog becomes a prince or a villain takes control of a superhero's body. Copyright 2004 The New York Times Company

Keyword: Development of the Brain
Link ID: 6101 - Posted: 06.24.2010

Bethesda, MD - A combination of luck and scientific curiosity has produced a mouse lacking two isoenzymes, MAO A and MAO B, that have been linked to violent criminal behavior and Parkinson's disease. The MAO A/B knockout mouse should provide an excellent model in which to address the specific roles of these neurotransmitters and their receptors in anxiety and stress-related disorders. The research appears as the "Paper of the Week" in the September 17 issue of the Journal of Biological Chemistry, an American Society for Biochemistry and Molecular Biology journal. The monoamine oxidase isoenzymes MAO A and MAO B are involved in breaking down neurotransmitters. Higher or lower than normal amounts of these isoenzymes result in irregular neurotransmitter levels, causing abnormal behavior. Realizing the connection between neurotransmitter levels and behavior, psychiatrists routinely use MAO A inhibitors as antidepressants and MAO B inhibitors for Parkinson's disease. By making knockout mice lacking either MAO A or MAO B, Jean C. Shih, a Professor at the University of Southern California School of Pharmacy, and her collaborators previously showed how each isoenzyme functions in the body. However, up until now, scientists have been unsuccessful at making a mouse lacking both MAO A and MAO B.

Keyword: Aggression; Emotions
Link ID: 6100 - Posted: 09.11.2004

Cannabis may loosen the stiff and spastic muscles of multiple sclerosis sufferers, and not just their minds, a follow-up study has found. The results contradict findings from the first phase of the study, where improvements seemed to be largely due to "good moods". “There does seem to be evidence of some benefit from cannabis in the longer term that we didn’t anticipate in the short term study,” says John Zajicek, at Peninsula Medical School in Exeter, UK, and one of the research team. In 2003, Zajicek and his colleagues published results on the largest study to date of cannabinoids and MS. The trial included 630 advanced-stage MS patients who took either cannabinoid compounds or a placebo for 15 weeks. Compared with those on placebos, patients who received active compounds said they both felt less pain and less muscle spasticity – the spasms characteristic of this neurodegenerative disease. © Copyright Reed Business Information Ltd.

Keyword: Multiple Sclerosis; Drug Abuse
Link ID: 6099 - Posted: 06.24.2010

Helen Pilcher A woman who stopped dreaming after a stroke is helping researchers unravel the mysteries of sleep. The 73-year-old patient was admitted to hospital after a stroke disrupted blood flow to an area at the back of her brain, called the occipital lobe. At first, her symptoms were not unusual - she lost some vision and was weak on one side of the body. But as the initial problems faded a few days later, a new symptom emerged: the woman had stopped dreaming. Her story is recorded in the Annals of Neurology1. She used to experience 3 to 4 dreams per week, says Claudio Bassetti, now of University Hospital Zurich in Switzerland, who studied the woman. After the stroke, she had no dreams for a whole year, yet her sleep and mental functions appeared otherwise unaffected. People have been fascinated by dreams for centuries. Psychologist Sigmund Freud believed that dreams offer a release for repressed feelings. Others think they help us empty our minds at the end of a busy day, or solve problems as we sleep. ©2004 Nature Publishing Group

Keyword: Sleep
Link ID: 6098 - Posted: 06.24.2010

By Karen Young Neuroscientists at the National Institute of Mental Health (NIMH) of the National Institutes of Health (NIH; both Bethesda, Maryland) have used brain imaging, specifically functional magnetic resonance imaging (fMRI), to help reveal how structural abnormalities in the brain can lead to functional abnormalities, offering insight into how genetic flaws may translate into cognitive symptoms in more common and complex major mental disorders. The research specifically focused on Williams syndrome, characterized by an inability to visualize an object as a set of parts and then construct a replica. People with Williams syndrome also tend to be "overly friendly and anxious and often have mental retardation and learning disabilities," according to the NIH. "Williams syndrome has been fascinating to people for decades because it has this very circumscribed psychological abnormality," lead investigator Andreas Meyer-Lindenberg, MD, told Medical Device Daily. "Usually when you have brain damage of any kind, in the case you do have mental retardation or difficulties, most faculties are affected to the same degree." Content © 2004 Thomson BioWorld

Keyword: Language; Brain imaging
Link ID: 6097 - Posted: 06.24.2010

By Paul Rincon, BBC News Online science staff, at the BA festival Parents of children with attention deficit hyperactive disorder (ADHD) often show signs of the condition themselves, research has suggested. University of Wales at Bangor scientists said this made dealing with their child's condition more difficult. But they told the British Association Festival of Science in Exeter that sharing these symptoms did not put the child at any greater risk. Nor did it mean ADHD adults necessarily had poor parenting skills, they argued. Children with ADHD have extreme difficulty sitting still, learning or concentrating; and looking after these children can be exhausting for parents. "Parenting a child with ADHD when you have symptoms yourself must be the most difficult thing to do." However, he said his study of over 250 parents and children indicated there might be some positive aspects to sharing ADHD traits between parent and child. The research confirms that in families with shared symptoms, ADHD parents are more likely to engage in negative and undesirable parenting practices, and have a negative emotional relationship with their child. But this group of parents is also more likely to engage in affectionate and constructive parenting when dealing with their child. This includes the parent expanding on a child's play idea, without criticism, and spending more time playing together, all of which are positive parenting traits. (C) BBC

Keyword: ADHD
Link ID: 6096 - Posted: 09.11.2004

Researchers have discovered a critical protein that regulates the growth and activation of neural connections in the brain. The protein functions in the developing brain, where it controls the sprouting of new connections and stimulates otherwise silent connections among immature neurons, and potentially in the mature brain as well, where it may play a role in memory formation. The researchers published their discovery of the protein, called dendrite arborization and synapse maturation 1, or Dasm1, in two papers in the September 7, 2004, issue of the Proceedings of the National Academy of Sciences. They were led by Howard Hughes Medical Institute investigators Yuh Nung Jan and Lily Yeh Jan. The first author on both papers was Song-Hai Shi in the Jans' laboratory at the University of California, San Francisco. Dendritic spines are mushroom-shaped protuberances that extend from the surface of the cable-like axon of a neuron. Dendrites receive chemical signals that trigger nerve impulses in the form of neurotransmitters launched from neighboring neurons. Growth of new dendrites can therefore increase the connection between neurons. Changes in the strength of connections, known as long-term potentiation, allow the brain to create memories. © 2004 Howard Hughes Medical Institute.

Keyword: Development of the Brain
Link ID: 6095 - Posted: 06.24.2010

Quality-control system in neurons triggers cell suicide when excessive accumulation of GM1 ganglioside in lysosomes disrupts protein folding inside endoplasmic reticulum Excess accumulation in brain cells of a fat molecule called GM1-ganglioside (GM1) disrupts the folding of newly assembled proteins into their proper shapes, triggering nerve degeneration and mental retardation in children. This finding, from investigators at St. Jude Children's Research Hospital, is published in the Sept. 10 issue of Molecular Cell. The disease, called GM1 gangliosidosis, disrupts the normal function of brain cells and causes them to self-destruct. The St. Jude discovery offers strong evidence for the cause of GM1 gangliosidosis in children. GM1 gangliosidosis is a lysosomal storage disorders, an inherited disease in which one or more enzymes in the lysosomes are defective. Lysosomes are the cell's recycling centers, where proteins, fats and other molecules are broken down into their basic building blocks, which are then reused to make new molecules. Lysosomal storage diseases occur when lysosomes lack the enzymes they need to perform their recycling tasks, leading to abnormal accumulation of the molecules the lysosome is supposed to break down. These diseases are responsible for most severe cases of nerve degeneration and mental retardation among children.

Keyword: Development of the Brain
Link ID: 6094 - Posted: 09.10.2004

Molly Brown was left profoundly deaf after her auditory nerves were removed during treatment for a genetic illness. But late last year she became one of the first people to be given a radical new type of implant that attempts to recreate hearing by stimulating the brainstem directly. Of the five who received the implant, she has had the most success. She still finds the telephone difficult, so when she told Duncan Graham-Rowe about her strange new world they used instant messaging When did you first notice problems with your hearing? In 1982, when I was 22, I noticed I was having some difficulty talking on the phone. The sound seemed to be getting softer and more garbled. What did you do? I went to an ear doctor, who diagnosed "sinus difficulties". But it was getting worse, so after another year I switched doctors. My new doctor straightaway suspected a brain tumour. He said, "You are too young to lose that much hearing." What was the diagnosis? I had neurofibromatosis type II (NF2), although it wasn't diagnosed for certain until last October. It is a disease in which chromosome 22 basically tells your body to develop non-malignant growths or tumours on the hearing nerves, spine and sometimes elsewhere in your body. It is present at conception. You know, I almost feel better knowing that I have had this from day one and that I was not doing something "wrong". © Copyright Reed Business Information Ltd.

Keyword: Hearing
Link ID: 6093 - Posted: 06.24.2010

Challenging decades of scientific belief that the decoding of sound originates from a preferred side of the brain, UCLA and University of Arizona scientists have demonstrated that right-left differences for the auditory processing of sound start at the ear. Reported in the Sept. 10 edition of Science, the new research could hold profound implications for rehabilitation of persons with hearing loss in one or both ears, and help doctors enhance speech and language development in hearing-impaired newborns. "From birth, the ear is structured to distinguish between various types of sounds and to send them to the optimal side in the brain for processing," explained Yvonne Sininger, Ph.D., visiting professor of head and neck surgery at the David Geffen School of Medicine at UCLA. "Yet no one has looked closely at the role played by the ear in processing auditory signals." Scientists have long understood that the auditory regions of the two halves of the brain sort out sound differently. The left side dominates in deciphering speech and other rapidly changing signals, while the right side leads in processing tones and music. Because of how the brain's neural network is organized, the left half of the brain controls the right side of the body, and the left ear is more directly connected to the right side of the brain.

Keyword: Hearing; Laterality
Link ID: 6092 - Posted: 09.10.2004

A grand tradition in the study of the brain is to wait for disaster to strike. The functional map of the brain--identifying which areas underlie movement, different senses or emotions, memory, and so on--has largely been filled in by observing which functions were eliminated or changed with injuries or strokes to focal areas of the brain. In a study published September 10, 2004, in the online edition of the Annals of Neurology, scientists describe a patient who lost all dreaming, and very little else, following a stroke in one distinct region of the brain, suggesting that this area is crucial for the generation of dreams. "How dreams are generated, and what purpose they might serve, are completely open questions at this point. These results describe for the first time in detail the extent of lesion necessary to produce loss of dreaming in the absence of other neurological deficits. As such, they offer a target for further study of the localization of dreaming," said author Claudio L. Bassetti, M.D., of the Department of Neurology at the University Hospital of Zurich in Switzerland. These unique scientific observations began with an unfortunate event: a stroke suffered by a 73-year-old woman. When blood flow was disrupted to a relatively small area deep in the back part of her brain, she lost a number of brain functions.

Keyword: Sleep
Link ID: 6091 - Posted: 09.10.2004

Michael Hopkin A brain-imaging study has shed light on why some people are more susceptible than others to hypnosis. By hinting at the brain processes involved, the analysis also suggests that hypnosis - both the stage and therapeutic varieties - does have genuine effects on the brain's workings. Those who are easily hypnotized show different activity in a brain region called the anterior cingulate gyrus, which is involved in planning our future actions, reports John Gruzelier of Imperial College London. In a hypnotic trance, the function of this region may be impaired, he says, meaning that subjects are more likely to follow a hypnotist's suggestion: "The hypnotist tells you to go with the flow, and so you don't evaluate what you're doing." This is consistent with the idea that those who are easiest to hypnotize tend to describe themselves as generally letting go of their inhibitions quite easily, Gruzelier told the British Association Festival of Science in Exeter, UK, on Thursday. Some experts have argued that hypnotism is not a real physiological phenomenon at all, but rather the result of hypnotists imposing themselves on their subjects, who may be simply swept along. Stage hypnotists are often accused of intimidating their 'volunteers' into playing along for the sake of the show. ©2004 Nature Publishing Group

Keyword: Brain imaging; Attention
Link ID: 6090 - Posted: 06.24.2010

By Christopher Shea ATTENTION, NEW PARENTS. Jerome Kagan, a professor emeritus of psychology at Harvard, has devised a fun little test for you. At 4 months old, plop your baby into a bouncy seat and present him with a series of colorful new toys - ones he's never seen - one after the other, for 20 seconds at a time. Does he cry madly and shake his arms and legs? If yes, be forewarned: Your baby may be at higher risk for "developing serious anxiety over social interactions" a decade down the road. If he screams at 4 months, he'll be more likely to stay home from junior-high dances. If he screams, he'll be more likely to answer "no" when a psychologist asks, at age 11, "Are you happy most of the time?" It won't really matter if you cuddled your child as an infant or showered him with play dates as a toddler. He'll probably never be a brash CEO or politician, although he might become a brilliant solitary researcher or a melancholy poet. On the other hand, if your baby just stares calmly at the toys, he will be calm on dates but also slightly more likely to become a delinquent, because parental threats won't faze him. © Copyright 2004 Globe Newspaper Company.

Keyword: Development of the Brain
Link ID: 6089 - Posted: 06.24.2010

by Arline Kaplan, Psychiatric Times August 2004 Vol. XXI Issue 9 Although eating disorders have been considered to be largely sociocultural in origin, findings from family, twin and molecular genetic studies conducted during the last decade are refuting that perspective, an expert in genetic epidemiology told attendees at the recent 2nd World Congress on Women's Mental Health in Washington, D.C. (Bulik et al., 2004). "Twenty years ago when I started in this field, and gave my favorite lecture on eating disorders, it was all about the role of the family and social factors in the etiology of eating disorders," said Cynthia M. Bulik, Ph.D., William R. and Jeanne H. Jordan Distinguished Professor of Eating Disorders in the department of psychiatry and director of the eating disorders program at the University of North Carolina, Chapel Hill. "Both anorexia and bulimia were very much viewed as disorders of choice. These young girls were viewed as trying to emulate some cultural ideal and diet themselves down to a certain weight. Now, any patient would have told you had you listened that wasn't what they were doing. They went far beyond any societal ideal in Cosmopolitan or any other magazine." Bulik explained that when she and colleagues started talking about genes as being involved in these disorders, "people pretty much thought we were out of our minds." However, the investigators are discovering a complex interplay between genes and the environment leading to the development of anorexia nervosa (AN) and bulimia nervosa (BN). © 2004 Psychiatric Times

Keyword: Anorexia & Bulimia
Link ID: 6088 - Posted: 06.24.2010

by Amir Raz, Ph.D., Psychiatric Times August 2004 Vol. XXI Issue 9 In the United States, approximately 2% to 6% of school-age children are diagnosed with attention-deficit/hyperactivity disorder. Data show that stimulant medication is the most consistently successful form of treatment in ADHD, with psychostimulants such as dextroamphetamine (Adderall, Dexedrine) and methylphenidate (Ritalin) exerting therapeutic effects via modulation of the noradrenergic and dopaminergic systems. In the United States, methylphenidate is used to treat over 2 million children with ADHD annually. Methylphenidate acts primarily by blocking the dopamine transporter and increasing extracellular dopamine in the striatum. Despite more than 50 years of clinical and neuroscientific research, appropriate diagnostic and therapeutic interventions for ADHD are still an issue for many people, and although reports summarize the current knowledge (American Academy of Pediatrics Subcommittee on Attention-Deficit/Hyperactivity Disorder and Committee on Quality Improvement, 2001), they use parameters that are still based on the same descriptive determinations that have plagued the field for years. Stimulants are thus widely prescribed for the treatment of ADHD even though the mechanisms subserving their calming effects are not easily understood. The past two decades have ushered in a new era of methodological advances in tools for noninvasive imaging of the living brain. Brain imaging has forged an impressive link between psychology, psychiatry and neuroscience. The information gleaned from such advances has been used to study both the anatomical and functional aspects of neural processing. © 2004 Psychiatric Times.

Keyword: ADHD
Link ID: 6087 - Posted: 06.24.2010

by Antonio Mantovani, M.D., Ph.D., and Sarah H. Lisanby, M.D. Psychiatric Times August 2004 Vol. XXI Issue 9 Transcranial magnetic stimulation (TMS) is a non-invasive means of stimulating focal regions of the brain using magnetic fields. Since its introduction in 1985, TMS has been used to study localization of brain functions, connectivity of brain regions and pathophysiology of neuropsychiatric disorders. The potential uses of TMS to treat psychiatric disorders are under active study. This article reviews the state of knowledge about the therapeutic potential of TMS in psychiatry. Transcranial magnetic stimulation is an investigational medical procedure performed by placing an electromagnetic coil on the scalp (Figure). High-intensity current is rapidly turned on and off in the coil through the discharge of a capacitor. This produces a time-varying magnetic field that lasts for about 100 to 200 microseconds. The magnetic field strength is about 1.5 to 2 tesla (about the same intensity as the static magnetic field used in clinical magnetic resonance imaging) at the surface of the coil, but the strength of the magnetic field drops off exponentially with distance from the coil. The proximity of the brain to the time-varying magnetic field results in current flow in neural tissue and in membrane depolarization. Transcranial magnetic stimulation is experimental; it is not approved by the U.S. Food and Drug Administration for the treatment of any disorder. A striking effect of TMS occurs when one places the coil on the scalp over the primary motor cortex. A single TMS pulse of sufficient intensity causes involuntary movement in the muscle represented by that region of cortex. © 2004 Psychiatric Times.

Keyword: Depression
Link ID: 6086 - Posted: 06.24.2010