By BENEDICT CAREY ANAHEIM, Calif. - The small car careered toward a pile of barrels labeled "Danger TNT," then turned sharply, ramming through a mock brick wall and into a dark tunnel. A light appeared ahead, coming fast and head-on. A locomotive whistled. "Uh-oh," said one of the passengers, Dr. Martin Seligman, a psychologist and a pioneer in the study of positive emotions. But in a moment, the car scudded safely under the light, out through the swinging doors of Mr. Toad's Wild Ride and into the warm, clear light that seemed to radiate from the Southern California pavement. "Well," Dr. Seligman said. "I don't know that I expected to be doing that." One of several prominent therapists who agreed to visit Disneyland at the invitation of this reporter, Dr. Seligman was here in mid-December for a conference on the state of psychotherapy, its current challenges and its future. And a wild ride it was. Because it was clear at this landmark meeting that, although the participants agreed it was a time for bold action, psychotherapists were deeply divided over whether that action should be guided by the cool logic of science or a spirit of humanistic activism. The answer will determine not only what psychotherapy means, many experts said, but its place in the 21st century. Copyright 2005 The New York Times Company

Keyword: Depression
Link ID: 8336 - Posted: 12.29.2005

J. Scott Yaruss Stuttering is a communication disorder generally characterized by involuntary disruptions in the flow of speech. These disfluencies can take many forms, such as repetitions of parts of words (“li-li-like this”) and moments when a sound or a period of silence is prolonged (“lllllike this” or “l-----ike this”). Individuals who stutter often experience negative emotional, cognitive or behavioral reactions that can further affect their ability to communicate. Ultimately, stuttering can have a significant adverse impact on an individual’s quality of life and ability to participate in daily activities. The stuttering classification encompasses a number of communication disorders: neurogenic stuttering and psychogenic stuttering are associated with sudden onset and, as their names imply, with a specific known cause--either a flaw in the makeup of the brain or a profound psychological challenge. These disorders are relatively rare and differ in terms of etiology, symptoms and treatment from developmental stuttering, the most common disorder. Developmental stuttering typically starts in early childhood, between the ages of two and a half and four. The onset of the disorder, which can be gradual or relatively sudden, generally occurs during the period of rapid development in a child’s language skills, motor skills, temperament, and social interaction. Later onset of developmental stuttering has also been reported, though less is known about this variant. The causes of developmental stuttering are not well understood and various theories have been offered throughout the history of speech-language pathology. The roots of stuttering have been attributed to a number of causes: emotional problems, neurological problems, inappropriate reactions by caregivers and family members, language planning, and speech motor difficulties, among others. © 1996-2005 Scientific American, Inc.

Keyword: Language; Development of the Brain
Link ID: 8335 - Posted: 06.24.2010

By Mary Beckman Marijuana has a reputation for making people dash to the kitchen (or the nearest convenience store). New research shows why and helps explain how a hormone called leptin usually keeps the appetite under control. The results may help scientists design better diet drugs. Researchers have known for several years that a connection exists between leptin and cannabinoids, the molecules in the brain that stimulate appetite and that are related to those found in marijuana (ScienceNOW, April 11 2001). Mice that don't make leptin have oversized appetites, for example, and they have unusually high concentrations of cannabinoids in the hypothalamus. But no one knew how leptin and cannabinoids interacted in the brain. To examine the relation, Young-Hwan Jo, now at the Albert Einstein College of Medicine, New York City, and colleagues, took a look at slices of mouse hypothalamus. When the team dropped a cannabinoidlike compound onto the neurons, the neurons fired. If the researchers added leptin first, the neurons did not activate. © 2005 American Association for the Advancement of Science.

Keyword: Obesity; Drug Abuse
Link ID: 8334 - Posted: 06.24.2010

Susan Milius New videos of ants fixing an entrée of fruit fly stew show that it's the youngsters who do the colony's version of cooking. What's more, they don't nibble as they cook but wait to be served their fair share. Ants prepare their meat not by heating but by marinating it with digestive enzymes to create a glistening protein slurry. With their hourglass figures, adult ants have such tiny waists that solid food can't pass through to their abdomens. Biologists already knew that the blob-shaped larvae predigest meat. Some scientists had suggested that the adults feed meat to the larvae and return later for some regurgitated protein slurry. That's not what happened, though, in videos of lab colonies of pinhead-size Pheidole spadonia, says Deby Cassill of the University of South Florida in St. Petersburg. Adults placed lumps of prey in little hairy depressions on top of the larvae's bellies, and for some 5 hours, larvae drooled digestive enzymes over the meat as it dissolved into a protein drink. The adults collected the slurry to distribute, but during the kitchen prep, the youngsters rarely took a swallow themselves. ©2005 Science Service.

Keyword: Evolution
Link ID: 8333 - Posted: 06.24.2010

By Jennifer Viegas, Discovery News — Horses prefer fenugreek, banana and cherry-flavored feed to all other flavors, according to one of the most detailed studies yet on horse flavor preferences. Three of the most popular flavors added to commercial horse feed — molasses, garlic and mint — did not fare nearly as well. In fact, most horses in the study rejected garlic-flavored food, unless it was their only choice. According to the study, which is published in this month's Applied Animal Behavior Science, horses ranked flavors as follows: fenugreek, banana, cherry, rosemary, cumin, carrot, peppermint and oregano. Many horse enthusiasts in Western countries feed their horses apples, but the eight competition-breed horses in the study liked the flavor of bananas better. "Horses tend to be fed food that is cheap and local, so what they are offered will vary around the world," said Deborah Goodwin, lead author of the study. "We offer horses apples in the U.K., but in Japan they are expensive and people gift wrap them and give them to each other as presents." © 2005 Discovery Communications Inc.

Keyword: Chemical Senses (Smell & Taste)
Link ID: 8332 - Posted: 06.24.2010

Charlotte Schubert Our perception of colours can depend on whether we view them from the left or the right, scientists have found. They say this demonstrates how language can alter the way we see the world. The idea that language can affect cognition is not new. In the 1930s, the American linguist Benjamin Lee Whorf proposed the controversial hypothesis that the structure of language affects the way people think. Later studies have hinted that this may be true in some circumstances (see 'Tribes without names for numbers cannot count'). But whether language affects our perception of the world has remained an open question. Richard Ivry of the University of California, Berkeley, and colleagues suspected that separating out the effects of visual input to the right and left brain hemispheres might yield some clues. Language is processed mainly in the left hemisphere of the brain, which also deals with signals from the left side of the retinas in both our eyes. Because light from objects to our right falls mainly into the left-hand area of our retinas, the researchers hypothesized that colours to the right would feel the influence of language more keenly. Conversely, objects on our left side activate the right hemisphere of the brain, so the effect of language would be minimal. ©2005 Nature Publishing Group

Keyword: Vision; Laterality
Link ID: 8331 - Posted: 06.24.2010

Gaia Vince Reindeer have a body clock that does not rely on a 24-hour day/night light cycle, according to Norwegian researchers. It may explain how they stay awake to carry out their Christmas duties. Instead, the herbivores’ stomachs seem to keep their body clocks ticking along. Karl-Arne Stokkan at the University of Tromsø, and colleagues, logged the festive animals’ movements every 10 minutes for a year using a radio transmitter device embedded in collars around the reindeers’ necks. The collars were placed on 12 reindeer – six who roamed a mountainous region of mainland Norway at a latitude of 70° North, and six found in the more-northerly Arctic archipelago of Svalbard (78° N). Winter in these regions is unyieldingly dark, while in summer the Sun does not set. Spring and autumn provide just a few weeks of night/day cycles. In the absence of light stimuli humans, like most mammals, naturally revert to a 6 to 8-hour sleep pattern due to an inbuilt circadian rhythm. © Copyright Reed Business Information Ltd

Keyword: Biological Rhythms
Link ID: 8330 - Posted: 06.24.2010

By introducing expression of a special green-algae gene into neurons of the tiny, transparent nematode C. elegans, researchers have been able to elicit specific behavioral responses by simply illuminating animals with blue light. The work paves the way for better understanding of how neurons communicate with each other, and with muscles, to regulate behavior in intact, living organisms. Generally speaking, detailed information about the activity and function of specific neurons during particular behaviors has been difficult to achieve in undissected animals. The new findings are reported by Alexander Gottschalk and colleagues at Goethe-University Frankfurt and at the Max Planck Institute for Biophysical Chemistry, also in Frankfurt. In their new study, the researchers employed a light-sensitive protein from the green alga Chlamydomonas reinhardtii. This protein, channelrhodopsin-2 (ChR2), sits in cell membranes, where it gates the flow of certain ions from one side of the membrane to the other. Such so-called channel proteins play central roles in the activities of neurons and muscle cells, and while some channel proteins are sensitive to chemicals or electrical signals, ChR2 and its relatives are controlled directly by certain wavelengths of light, making them ideal for remote control in the laboratory. In their experiments, the researchers took advantage of the light sensitivity of the algal channel protein by introducing expression of a modified form of ChR2 in specific C. elegans neurons and muscle cells. The researchers found that when this form of ChR2 was expressed in muscle cells, blue-light activation of the protein was sufficient to cause strong contraction of the muscle. They found that muscle contraction was simultaneous with light exposure.

Keyword: Pain & Touch
Link ID: 8329 - Posted: 12.20.2005

By Stacey Colino, Special to The Washington Post Like most teenagers, Andrew Solomon was often at the mercy of his moods -- but in his case this situation persisted into his thirties. "During my up periods, I'm lucid and articulate," said Solomon, author of the partly autobiographical "The Noonday Demon: An Atlas of Depression," which won the National Book Award for nonfiction in 2001. "I have clarity and can see patterns in my work, and I can write loads of publishable material in one night. I'm also very affectionate with people I care about." But when his moods would turn, as they invariably did, he could withdraw or have angry outbursts. Once, after an annoying phone call, he slammed down the phone so hard it broke. Another time, when an acquaintance who frequently drank too much showed up at his home tipsy and immediately poured herself a cocktail, Solomon "smashed the glass and yelled at her that she had to leave immediately," he recalls. After such explosions, he would "spend the next week apologizing." Yet it wasn't until three years ago that Solomon, now 42, learned there is a word for the mood swings that have affected him since his youth: cyclothymia. Cyclothymic disorder, as it is sometimes known, is a milder cousin of bipolar disorder. Like bipolar disorder, cyclothymia has high and low phases, though the highs are not as high and the lows not as low. It can be crippling nonetheless. And it is a risk factor for bipolar disease itself, with up to 50 percent of those with cyclothymia eventually developing bipolar disorder. Major depression is also a higher risk. © 2005 The Washington Post Company

Keyword: Depression; Schizophrenia
Link ID: 8328 - Posted: 06.24.2010

Morphine and other opioids work wonders for pain. Unfortunately, their effectiveness declines over time while their addictiveness grows, meaning patients need the drug even as it affords them less and less relief. But new research into the cellular workings of opioids offers a promising new pathway to improved pain relief--without the addiction--by triggering one receptor and blocking another. Medicinal chemist Philip Portoghese of the University of Minnesota and his colleagues began by studying two of the four major opioid receptors in the cells of the central nervous system. Each bears the name of a Greek letter and the chemists focused on the Mu and Delta receptors. Previous research had shown that drugs that linked up with Mu receptors lasted longer with less addiction when combined with drugs that blocked Delta receptors. But it was not known whether the two channels worked separately or in concert to improve the overall effect. So Portoghese and his colleagues built a drug that triggered the Mu receptor while blocking the Delta receptor--dubbed MDAN, for Mu Delta agonist antagonist. They administered various versions of the drug to mice and then tested their sensitivity to pain by focusing a hot light on their tails and recording the time it took the animals to move them. The MDAN drug proved roughly 50 times more effective than morphine in blocking pain, the researchers report in this week's online edition of the Proceedings of the National Academy of Sciences. But MDAN still paled in comparison to drugs designed purely to stimulate the Mu receptor, which exhibit more than 100 times the pain blocking potential of morphine. The MDAN drugs had another benefit, however: the mice did not develop any dependence. © 1996-2005 Scientific American, Inc

Keyword: Pain & Touch; Drug Abuse
Link ID: 8327 - Posted: 06.24.2010

Our ability to understand speech or decide which fruit in the store is freshest depends on the brain's dexterity in integrating information over time. The prefrontal cortex, where working memory resides, plays a critical role in helping us make these countless everyday decisions. A novel computational study by Brandeis researchers in this week's issue of the Proceedings of the National Academy of Sciences proposes for the first time a neuronal model for the mechanisms underlying a time-related task in this complex decision-making process. Essentially, the study shows that neurons in the prefrontal cortex fire with greater or lesser intensity to finely control, or inhibit behavior, based on a neuronal feedback signal, or circuit mechanism. Such integral feedback control is probably at work in many regulatory areas of the body, such as temperature control and feelings of satiety to prevent overeating, but this is the first time this mechanism has been suggested as a role of neuronal firing. The findings provide a framework for understanding how neurons operate in a part of the brain that controls behavior and which is often compromised in people with mental health problems such as schizophrenia, a disease that can entail problems with short-term memory tasks and misperceptions about the immediate environment.

Keyword: Learning & Memory
Link ID: 8326 - Posted: 12.20.2005

Darwin’s fingerprints can be found all over the human genome. A detailed look at human DNA has shown that a significant percentage of our genes have been shaped by natural selection in the past 50,000 years, probably in response to aspects of modern human culture such as the emergence of agriculture and the shift towards living in densely populated settlements. One way to look for genes that have recently been changed by natural selection is to study mutations called single-nucleotide polymorphisms (SNPs) – single-letter differences in the genetic code. The trick is to look for pairs of SNPs that occur together more often than would be expected from the chance genetic reshuffling that inevitably happens down the generations. Such correlations are known as linkage disequilibrium, and can occur when natural selection favours a particular variant of a gene, causing the SNPs nearby to be selected as well. Robert Moyzis and his colleagues at the University of California, Irvine, US, searched for instances of linkage disequilibrium in a collection of 1.6 million SNPs scattered across all the human chromosomes. They then looked carefully at the instances they found to distinguish the consequences of natural selection from other phenomena, such as random inversions of chunks of DNA, which can disrupt normal genetic reshuffling. © Copyright Reed Business Information Ltd.

Keyword: Evolution
Link ID: 8325 - Posted: 06.24.2010

On average, twins of people who have been diagnosed with dementia score lower on cognitive tests than do the twins of people without dementia, new research has found. The study, which included more than 100 Swedish twins age 65 and older, also found that, on average, identical twins of people with dementia have poorer cognitive skills than do fraternal (non-identical) twins of people with dementia. The researchers suggest that these differences in thinking skills reflect a genetic risk for dementia. However, they emphasize that cognitive changes and elevated genetic risk do not always predict that twins or siblings of people with dementia will eventually develop dementia themselves. The research, reported in the December 2005 issue of the Journal of Geriatric Psychiatry and Neurology, was led by Margaret Gatz, Ph.D., of the University of Southern California and the Karolinska Institute in Sweden. The study was funded by the National Institute on Aging (NIA), a component of the National Institutes of Health, U.S. Department of Health and Human Services, and a Zenith Award from the Alzheimer's Association. The University of Southern California Alzheimer's Disease Center is one of more than 30 Alzheimer's Disease Centers nationwide supported by the NIA. "This research is intriguing because it associates genetic risk for dementia with twins' cognitive deficits, even in the absence of dementia," says Neil Buckholtz, Ph.D., chief of the Dementias of Aging Branch of NIA's Neuroscience and Neuropsychology of Aging Program. "The differences in cognitive deficits between identical and fraternal twins are also important, suggesting that the twins who were more similar genetically had the greater risk."

Keyword: Alzheimers; Genes & Behavior
Link ID: 8324 - Posted: 12.20.2005

By THE ASSOCIATED PRESS ANCHORAGE, (AP) - Lloyd Leavitt shrugs off the subzero freeze that blankets the town of Barrow, Alaska, each winter. It is the weeks of endless night that get to him, filling him with insatiable cravings for carbohydrates, sleep and natural light. "There comes a time when you don't know if it's morning or evening; you get confused," said Mr. Leavitt, who has lived all his 49 years in Barrow, the nation's highest-latitude community. Mr. Leavitt has plenty of company when it comes to dealing with Alaska's dark side. No matter how far south you go, the state is still far north of the rest of the country. That means abbreviated days that get increasingly short as you travel farther north. Winter brings shorter days and extreme cold in other states as well. But Alaska is the American vortex of seasonal blues. No wonder residents here eagerly await the passing of winter solstice, the psychological turning point toward spring. The sun will not rise again in Barrow for another month after the solstice, which falls on Wednesday. For those in Barrow, a largely Inupiat Eskimo town of 4,500, that day marks the countdown to daylight, which is celebrated in a three-day April festival. Copyright 2005The New York Times Company

Keyword: Depression; Biological Rhythms
Link ID: 8323 - Posted: 12.19.2005

By Robert Roy Britt After hitting a 565-foot home run, Mickey Mantle once said, "I just saw the ball as big as a grapefruit." During a slump, Joe "Ducky" Medwick of the St. Louis Cardinals said he was "swinging at aspirins." A new study puts some science behind those perceptions. Researchers found a correlation between batting averages of softball players and how big or small they perceived the ball to be. After games at several softball fields in Charlottesville, Va., the researchers asked 47 players to pick from eight different-sized circles the one that best represented the size of the ball they had been trying to hit. "Only people who hit .500 or above pointed at the big circle," said Jessica Witt, a cognitive psychology doctoral candidate at the University of Virginia. The softball players literally see the ball as larger, the study concludes. "It's not in their minds. It's in perception," Witt told LiveScience. Witt was not surprised. She competed last July for the gold medal-winning U.S. Ultimate Frisbee team at the 2005 World Games in Duisburg, Germany. She has experienced a similar effect. © 2005 MSNBC.com

Keyword: Vision
Link ID: 8322 - Posted: 06.24.2010

By Clifford Singer, M.D., and Alison Bahr, M.A. Changes in sleep are inevitable as people age, though some sleep symptoms may be due to diseases rather than aging itself (Foley et al., 1999). For example, 41% of a study sample of older adults with ≥4 medical conditions considered themselves to be fair or poor sleepers as compared to 22% with one to three conditions and only 10% of those with none (Foley et al., 2004). In this same study, poor sleep was most strongly associated with heart disease, depression, arthritis and obesity. However, even healthy seniors experience reductions in slow-wave sleep ("deep sleep") and have lower sleep efficiency with more nighttime awakenings than younger adults (Bliwise, 1993). Patients with Alzheimer's disease (AD) may have the same sleep disturbances seen in other seniors, and, early in the course of AD, their sleep may not differ markedly from age-matched controls (Vitiello et al., 1990). In some cases, however, the sleep disturbance may be a marker for early AD. For example, investigators have reported that insomnia is an independent risk factor for cognitive decline over a three-year follow-up period (Cricco et al., 2001). Sleep-related problems generally increase as AD progresses (Moe et al., 1995). Patients with AD experience more frequent nighttime awakenings, daytime sleep increases, and both slow-wave sleep and rapid eye movement (REM) sleep are decreased (Bliwise, 1993; Prinz et al., 1982; Vitiello and Borson, 2001; Vitiello et al., 1992). Subjective sleep disturbances occur in up to 54% of patients with AD who live in the community (Carpenter et al., 1995; Chen et al., 2000; Hart et al., 2003; McCurry et al., 1999). McCurry et al. (1999) reported that 24% of caregivers report being awakened at night by the patient with AD and 40% report that patients with AD sleep more than usual. © 2005 Psychiatric Times.

Keyword: Alzheimers; Sleep
Link ID: 8321 - Posted: 06.24.2010

By Ewald Horwath, M.D., and Sara Siris Nash, M.D. Patients with HIV infection are at risk of developing psychiatric symptoms and disorders similar to those seen in the general population. Even before infection, people at risk for HIV may come from certain populations--such as injection-drug users and others with substance abuse or dependence--in whom there is a higher than average risk for psychiatric illness (Pillard, 1988; Rounsaville et al., 1982). Symptoms of anxiety and depression may be related to apprehension about disease progression and death and sadness from the loss of health, friends and income (Forstein, 1984; Nichols, 1985; Ostrow, 1987). Several studies have found a substantial risk for DSM-III major depression and adjustment disorders with anxious or depressed mood, which may occur during asymptomatic infection (Dilley et al., 1985; Holland and Tross, 1985). In addition, patients living with an underlying mental illness--especially severe and persistent mental or mood disorders--are at a disproportionately increased risk of developing infection with HIV due to sexual and substance use behaviors (Carey et al., 2004). Shortly after the initial HIV infection, the virus enters the central nervous system and may cause meningitis or encephalitis. Other serious CNS complications tend to occur late in the course of disease, when immune function has significantly declined, though studies have reported conflicting results as to the predictive value of CD4 counts in assessing cognitive and motor performance (Bornstein et al., 1991; Goethe et al., 1989; Koralnik et al., 1990; McArthur et al., 1989; Miller et al., 1990; Saykin et al., 1988). Viral load is more closely associated with the degree of cognitive impairment. © 2005 Psychiatric Times.

Keyword: Miscellaneous
Link ID: 8320 - Posted: 06.24.2010

Bruce Bower Preliminary evidence indicates that people can quell either temporary or chronic physical pain by learning to use their minds to reduce activity in a key brain area. Brain-imaging technology now enables individuals to use mental exercises to control a neural region that contributes to pain perception, say neuroscientist Sean C. Mackey of Stanford University and his colleagues. Both healthy volunteers and chronic-pain patients "learned to control their brains and, through that, their pain," Mackey holds. "However, significantly more testing must be done before this can be considered a treatment for chronic pain." The new findings appear in the Dec. 20 Proceedings of the National Academy of Sciences. Mackey's team studied 32 healthy volunteers, ages 18 to 37. First, each volunteer reported when an adjustable heat pulse applied to a leg produced pain that he or she rated as 7 out of 10, with 10 being equivalent to "the worst pain imaginable." Brain imaging of participants, using a functional magnetic resonance imaging (fMRI) scanner, showed that this level of pain was accompanied by pronounced blood flow—a sign of intense neural activity—in an area called the rostral anterior cingulate cortex. ©2005 Science Service.

Keyword: Pain & Touch
Link ID: 8319 - Posted: 06.24.2010

By Jennifer Viegas, Discovery News — Circus tigers increase their pacing ahead of performances, according to a new study whose authors believe that such behavior indicates the big cats positively anticipate their time on stage. The authors received cooperation and assistance from Feld Entertainment, Inc., the owners of Ringling Brothers and Barnum and Bailey Circus. Previously, the researchers analyzed other repetitive behavior, such as weaving, in circus elephants and came to a similar conclusion, which suggested the animals perked up before performing. "Elephants actually fight to do their act when they are held back," said Ted Friend, one of the researchers. "If the elephants are kept out of the ring, they will do their act outside." Friend, a professor in the Department of Animal Science at Texas A&M University, added, "That is what the elephants are accustomed to do. It's like humans going to work every day." He and his colleagues videotaped four tigers before and after performances for five days in 2002 and for four days in 2003. The researchers determined that pacing increased before performances. © 2005 Discovery Communications Inc.

Keyword: Learning & Memory; Emotions
Link ID: 8318 - Posted: 06.24.2010

Claire Ainsworth The seeds of sudden infant death syndrome seem to be planted in part by conditions in the mother's womb. The finding shows it is not just genetic factors that determine whether babies are predisposed to the tragic condition. And although it will not change doctors' advice to parents, it may shed some light on the causes of these mysterious deaths. Cot death, or sudden infant death syndrome (SIDS), is the name for the unexplained death of a baby, usually in its sleep. The condition strikes 1 in 2,000 babies in the developed world. Most cases are isolated. But it is known that a woman who has had one baby die from SIDS is five times more likely than other women to have a second baby die. This was once thought to cast suspicion on a mother's ability to care for her children. But it is now accepted that there are biological reasons for this recurrence, although it hasn't been clear what these are. To investigate, a team led by Gordon Smith, an obstetrician at the University of Cambridge, UK, studied the medical records of more than a quarter of a million women in Scotland. They compared three groups: those who had given birth to two surviving children; those whose first baby had died from SIDS, but whose second child did not; and those who first child did not die, but whose second baby did. ©2005 Nature Publishing Group

Keyword: Development of the Brain; Sleep
Link ID: 8317 - Posted: 06.24.2010