Where were we before we got sidetracked? It's tempting to blame cell phones, iPods and satellite radios for our distractibility, say researchers. But the more likely culprit is the aging brain. Changes in brain activity that begin gradually in middle age may explain why older adults find it hard to focus in busy environments, according to a study in this month's Journal of Cognitive Neuroscience. Canadian researchers compared brain scans of adults of various ages who were given a series of memory tasks. They found that advancing age inhibited the ability to turn off background chatter and concentrate on the task at hand. "Young adults can do this really well," said lead author Cheryl Grady, senior scientist with the Rotman Research Institute at Baycrest in Toronto. "This difference becomes less distinct in middle-age adults and is even less distinct in older adults." Seeking Focus One way to cope better: Limit multi-tasking. "Multi-tasking is a colloquial expression for what we refer to as a divided-attention problem," said David Madden, professor of medical psychology at Duke University Medical Center. "When people have to divide their attention, it's harder to concentrate." © 2006 The Washington Post Company

Keyword: Attention; Alzheimers
Link ID: 8536 - Posted: 06.24.2010

By SALLY SATEL, M.D. As a psychiatrist at a methadone clinic, I rarely encounter patients waving advertisements for the newest antidepressant or sleeping pill. Consumer-consciousness is just not big among our clientele. So I was surprised when a patient asked about "that pill for gambling addiction — maybe it would work for cocaine addiction, too." Ted was a 36-year-old heroin addict who stopped using once he began methadone but whose continuing cocaine habit increased in turn. Earlier that morning he heard a story on National Public Radio about a pill that helped pathological gamblers. "The gambler on the radio said the medication made him stop 'climbing the walls' and that he wasn't craving anymore," Ted told me. "That's what I need, something to make me not want." That, of course, is the timeless quest of addicts in recovery: not to want. More specifically, effortlessly not to want. But the very idea of a drug to treat addiction rankles others. Some experts are skeptical of substitution drugs, like methadone, because they produce dependence themselves. Others believe that treatment should break the addict's Pavlovian link between quick-fix relief and pill-taking. And psychotherapists often want a patient to feel the pain of his psychic conflicts in order to resolve them and thus eradicate the root cause of his addiction. Copyright 2006 The New York Times Company

Keyword: Drug Abuse
Link ID: 8535 - Posted: 06.24.2010

By ALIX SPIEGEL For most of the 20th century, therapists in America agreed on a single truth. To cure patients, it was necessary to explore and talk through the origins of their problems. In other words, they had to come to terms with the past to move forward in the present. Thousands of hours and countless dollars were spent in this pursuit. Therapists listened diligently as their patients recounted elaborate narratives of family dysfunction — the alcoholic father, the mother too absorbed in her own unhappiness to attend to her children's needs — certain that this process would ultimately produce relief. But returning to the past has fallen out of fashion among mental health professionals over the last 15 years. Research has convinced many therapists that understanding the past is not required for healing. Despite this profound change, the cliché of patients' exhaustively revisiting childhood horror stories remains. "Average consumers who walk into psychotherapy expect to be discussing their childhood and blaming their parents for contemporary problems, but that's just not true any more," said John C. Norcross, a psychology professor at the University of Scranton in Pennsylvania. Copyright 2006 The New York Times Company

Keyword: Depression; Schizophrenia
Link ID: 8534 - Posted: 06.24.2010

By MARK DERR I was drinking coffee in the kitchen one night a few years ago when I heard, emanating from our stereo system two rooms away, the unmistakable voice of Marilyn Monroe singing "Happy Birthday, Mr. President." Startled, I asked my wife, Gina, what that recording was doing on our stereo. "You're hallucinating," she said. "That's the Grateful Dead. It's not even close to 'Happy Birthday,' much less Marilyn Monroe." I think I have seen one Marilyn Monroe movie in its entirety, and I don't recall its title. Many years ago, I saw a film clip of her performance at Madison Square Garden in celebration of President John F. Kennedy's birthday. Despite Gina's assurances, I continued to hear Marilyn singing until I walked into the next room and met the familiar sound of Jerry Garcia and the Grateful Dead. We concluded that I had somehow conflated the Dead's song "Uncle John's Band" with some faint music from the next-door neighbor's house and transformed the two streams of sound into something completely different. The dopamine agonist I had started taking a few months earlier for Parkinson's disease carried a warning that hallucinations were a possible side effect. It had already caused sleep attacks, so, I thought, why not hallucinations? Copyright 2006 The New York Times Company

Keyword: Parkinsons
Link ID: 8533 - Posted: 02.14.2006

By NICHOLAS WADE When rats pause in running through a maze, they play back their memory of points along their route, but in reverse order. The discovery may provide a deep insight into how memory works in humans, as well as in rats. The reverse replay mechanism seems to be part of a neural editing process in which memories are selected, combined and stored as a set of edited movies, as it were, of important experiences in life. The mechanism was discovered by David J. Foster and Matthew A. Wilson at the Massachusetts Institute of Technology while they were studying the behavior of neurons in the rat's hippocampus, a brain region where new memories of location are formed. Their finding is reported in an article published online on Sunday by the journal Nature. The researchers were able to detect the reverse replay because of a set of electrodes that were stuck into individual neurons in the hippocampus. These neurons are known as place cells because each responds to a specific location in the rat's surroundings, in this case points along the maze. Though scientists have been aware of place cells for years, reverse replay had not been seen before because it occurs when the rats pause in the maze and seem to be doing nothing, Dr. Wilson said. Researchers had ignored this behavior because it did not seem to be important. Copyright 2006 The New York Times Company

Keyword: Learning & Memory
Link ID: 8532 - Posted: 02.14.2006

By Bjorn Carey To figure out how we pick mates, scientists have measured every shape and angle of the human face, studied the symmetry of dancers, crafted formulas from the measurements of Playboy models, and had both men and women rank attractiveness based on smelling armpit sweat. After all this and more, the rules of attraction for the human species are still not clearly understood. How it all factors into true love is even more mysterious. But a short list of scientific rules for the game of love is emerging. Some are as clearly defined as the prominent, feminine eyes of a supermodel or the desirable hips of a well-built man. Other rules work at the subconscious level, motivating us to action for evolutionary reasons that are tucked inside clouds of infatuation. In the end, lasting love depends at least as much on behavior as biology. But the first moves are made before you're even born. Starting at conception, the human body develops by neatly splitting cells. If every division were to go perfectly, the result would be a baby whose left and right sides are mirror images. But nature doesn't work that way. Genetic mutations and environmental pressures skew symmetry, a process with lifelong implications. © 2006 MSNBC.com © 2006 Microsoft

Keyword: Sexual Behavior; Hormones & Behavior
Link ID: 8531 - Posted: 06.24.2010

Seven-month-old infants cannot talk, nor can they do arithmetic. But a new study seems to show that babies do have an inherent sense of numbers, regardless of whether they can add two and two to get four. Neuroscientists Kerry Jordan and Elizabeth Brannon had previously shown that rhesus monkeys have a natural ability to match the number of voices they hear to the number of individuals they expect to see. When presented with a soundtrack of "coo" sounds, the monkeys chose to look at a picture containing the same number of fellow monkey faces. If the monkeys heard two coos, for example, they preferred to look at a picture of two monkeys rather than three and vice versa. The researchers expected the same to be true of human babies. But other studies with infants had delivered ambiguous results. Babies trained to expect to see two objects when presented with two tones stared longer at results that violated this convention, such as two tones and then three objects. And although babies matched up drumbeats and household objects in one study, efforts to duplicate the result failed. Jordan and Brannon argue that each of these studies was flawed, either because training might have skewed the response, or because the tasks were too difficult or the objects were irrelevant to a baby. © 1996-2006 Scientific American, Inc.

Keyword: Development of the Brain
Link ID: 8530 - Posted: 06.24.2010

Electroconvulsive therapy (ECT) – shock treatment –improves quality of life in patients with major depression, and that improved quality of life continues for six months, according to a report in the February Journal of Affective Disorders. The study was conducted in seven hospitals in New York City – two private psychiatric hospitals, three community hospitals and two academic medical centers, said W. Vaughn McCall, M.D., M.S., the lead author and professor and chairman of the Department of Psychiatry and Behavioral Medicine at Wake Forest University School of Medicine. "This study adds to the accumulating evidence that ECT is associated with a net health benefit in depressed patients who attain and sustain remission," wrote McCall and colleagues. ECT has long been known to be an effective treatment for major depression. The results from 283 severely depressed patients at the seven New York City hospitals confirm results from an earlier study McCall did of 77 ECT patients at Wake Forest University Baptist Medical Center, a study that was published in the November 2004 issue of the British Journal of Psychiatry. In that study, he said, "Quality of life and function are improved in ECT patients as early as two weeks after the conclusion of ECT." In the new study, the psychiatrists said, "ECT is associated with improved health-related quality of life in the short term and the long term." Most of the improvements were largely explained by the control of depressive symptoms, McCall said.

Keyword: Depression
Link ID: 8529 - Posted: 06.24.2010

All is fair in love and war — especially when the two are intertwined. Just ask the male Australian cuttlefish. "The male cuttlefish has quite a challenge on his hands when it comes to the end of their yearly life cycle," explains Roger Hanlon, senior scientist at the Marine Biological Laboratory. "There are four, five, even ten males for every female on the spawning grounds, so the challenge they face is, 'How do I get my genes into the next generation?' There's enormous competition among the males for the relatively few females that are on the spawning ground." Hanlon and his team spent five spawning seasons observing cuttlefish underwater in a remote coastal area of Australia. As one might expect, the largest males used their size advantage to find a female partner and guard her from other males. Hanlon observed that smaller males were able to get to the female while the guard male was fighting other males away, or by meeting the female in a "secret rendezvous" under a rock, for instance. But he found that the small males with the biggest success rate employ the same camouflage trick that allows them to escape predators: these so-called "sneaker" males change their skin pattern and body shape to disguise themselves as females, and swim right past a large guard male, who thinks he's getting another girlfriend. © ScienCentral, 2000-2006.

Keyword: Sexual Behavior
Link ID: 8528 - Posted: 06.24.2010

Researchers at a trio of universities have found that reactivating a specific memory does not affect associated or related memories, adding to our understanding of how memories are stored and influenced. The study appears in the latest issue of the Proceedings of the National Academy of Sciences. The study's authors are Jacek Debiec and Joseph LeDoux of New York University's Center for Neural Science, Valérie Doyère of NYU and Université Paris-Sud, and Karim Nader, a psychology professor at McGill University. Memories are made in stages. These initial stages involve learning followed by consolidation--a process during which the memory trace is formed. Unconsolidated memories are susceptible to disruption. Therefore, various pharmacological agents or interfering tasks applied before consolidation occurs prevent a memory from persisting. However, once consolidation occurs, memories may be long lasting--one experience may create memories that last a lifetime. For years it had been believed that consolidated memories were resistant to drug manipulations, which are effective in the early stages of memory formation. However, increasing number of data indicate that reactivation of consolidated memories renders them susceptible to treatments, which may result in either impairment or enhancement of the reactivated memory. This process is often referred to as reconsolidation, which has been proposed as a possible way of treating traumatic memories.

Keyword: Learning & Memory; Emotions
Link ID: 8527 - Posted: 02.14.2006

Up to 80% of the risk of developing Alzheimer's disease is genetic, a study has suggested. US researchers looked at almost 400 sets of elderly twins, where at least one had Alzheimer's. It also found that genetic factors appeared to determine when a person developed the condition. UK experts said the research, published in the journal Archives of General Psychiatry, would help quantify the role genetics played. Two-thirds of adults aged 65 years and older with dementia have Alzheimer's. The number of cases is expected to rise with the growing older adult population. Gene mutations which could affect risk have been found, but it is thought they only apply to a tiny number of cases. Scientists trying to determine whether genetic or environmental factors influence disease risk often study twins. Identical (monozygotic) twins share all their genes. So if a disease does have a strong genetic basis, it is likely to be seen in both or neither. But if only one has a condition, it is likely that environmental factors play a relatively greater influence. In the US study, researchers from the University of Southern California, Los Angeles, and colleagues identified 392 pairs of twins where one or both had Alzheimer's from the Swedish Twin Registry. (C)BBC

Keyword: Alzheimers; Genes & Behavior
Link ID: 8526 - Posted: 02.13.2006

Helen Pearson Idlers, loafers and layabouts, listen up. A new study suggests that the times when we sit around twiddling our thumbs could in fact be vital for learning. The idea stems from experiments in which neuroscientists eavesdropped on the brains of rats as they explored their environments. They found that the rats' brains 'replay' their experiences in reverse when the animals pause briefly to rest. The scientists, David Foster and Matthew Wilson working at the Massachusetts Institute of Technology in Cambridge, inserted a pincushion of fine wires into the animals' skulls. These allowed the team to simultaneously monitor the electrical activity of around 100 individual brain cells in the hippocampus, a brain region involved in learning and memory. The researchers placed each wired-up rat in a straight 1.5-metre run. They recorded brain-cell activity as the rats scurried up and down, pausing at each end to eat, groom and scratch their whiskers. As the rats ran along the track, the nerve cells fired in a very specific sequence. This is not surprising, because certain cells in this region are known to be triggered when an animal passes through a particular spot in a space. But the researchers were taken aback by what they saw when the rats were resting. Then, the same brain cells replayed the sequence of electrical firing over and over, but in reverse and speeded up. "It's absolutely original; no one has ever seen this before at all," says Edvard Moser, who studies memory at the Norwegian University of Science and Technology in Trondheim. ©2006 Nature Publishing Group

Keyword: Learning & Memory
Link ID: 8525 - Posted: 06.24.2010

The mystery of cot death may be explained by new research published online in Nature Neuroscience today [Sunday 12 February 2006]. A failure to 'gasp' has long been proposed as the basis for sudden infant death syndrome, or cot death. A team at the University of Bristol has discovered a subset of cells in the brain that have the ability to self-generate nervous impulses, which appear essential for gasping. These cells have been termed 'pacemakers'. Professor Julian Paton who heads up the research team at Bristol University said: "Our studies resolve a 15-year long controversy by showing that pacemaker cells in the brain appear responsible for gasping but not normal breathing. Importantly, cot death has been proposed to result from a failure of autoresuscitation and gasping." Using a unique experimental set-up developed in Bristol, Paton combined forces with two other world leaders in respiration – Dr. Jeffrey Smith (NIH, USA) and Professor Walter St.-John (Dartmouth, USA) – to discover how gasping works. They found that many different types of brain cells are essential for normal breathing, but only a small subset of these is required for gasping or autoresuscitation. If normal breathing should stop, this backup system is activated to induce gasping. This restores oxygen supplies and kick-starts the heart beat so that normal breathing can resume.

Keyword: Sleep
Link ID: 8524 - Posted: 06.24.2010

A new study to examine facial preference, has found that people are attracted to facial characteristics indicative of personality traits similar to their own Biological scientists at the University of Liverpool launched the study to investigate the reasons why many couples tend to look similar to each other. The team, in collaboration with the University of Durham and the University of St Andrews, asked participants to judge perceived age, attractiveness, and personality traits of real-life married couples. Photographs of female faces were viewed separately to male faces, so that participants were unaware of who was married to whom. Dr Tony Little, from the University's School of Biological Sciences, explains: "There is widespread belief that couples, particularly those who have been together for many years, look similar to each other. To understand why this happens, we looked at the assumptions that people make about a person's personality, based on facial characteristics. We found that perceptions of age, attractiveness and personality were very similar between male and female couples. For example if the female face was rated as 'sociable' then her partner was also more likely to be rated as 'sociable.' "We also found that couples who had been married for a long period of time, were perceived as having more similar personalities than those who had not been together very long. This may come from sharing experiences together - affecting how their face appears."

Keyword: Sexual Behavior
Link ID: 8523 - Posted: 02.11.2006

Washington, D.C. — Based on laboratory research, scientists at Georgetown University Medical Center have a new theory as to why people with Alzheimer's disease have trouble performing even the simplest memory tasks, such as remembering a family member’s name. That’s because they discovered a physical link between apolipoprotein E (APOE), the transport molecules known to play a role in development of the disease, and glutamate, a brain chemical necessary for establishing human memory. In a study published in the Journal of Biological Chemistry, the research team specifically found that receptors on the outside of brain nerve cells (neurons) that bind on to APOE and glutamate are connected on the surface of neurons, separated from each other by only a small protein. While the researchers don’t know why these receptors are linked together, they say inefficient or higher-than-average levels of APOE in the brain could possibly be clogging these binding sites, preventing glutamate from activating the processes necessary to form memories. “We have found out that two receptors previously thought to have nothing to do with each other do, in fact, interact, leading us to conclude that APOE affects the NMDA glutamate channel that is important in memory,” says the study’s senior author, G. William Rebeck, PhD, associate professor of neuroscience in Georgetown’s Biomedical Graduate Research Organization.

Keyword: Alzheimers
Link ID: 8522 - Posted: 06.24.2010

Researchers have linked a hormone known to adjust levels of key brain chemicals to the quality of our hearing as we age. The more of the hormone that older people have in their bloodstream, the better their hearing is, and the less of the hormone, the worse their hearing is. The hormone, aldosterone, is known to regulate kidney function and also plays a role in controlling levels of two crucial signaling chemicals in the nervous system, potassium and sodium. For nerves to send signals crisply and work properly, potassium and sodium must be in precise proportion, without any disruption in the molecular channels or gates through which they move. Levels of potassium are particularly crucial in the sensitive inner ear, where fluid rich in potassium plays a central role in converting sounds into signals that the nervous system recognizes. The team of scientists in Rochester, N.Y., put 47 healthy men and women between the ages of 58 and 84 through a battery of sophisticated hearing tests. Scientists also measured their blood levels of aldosterone, which is known to drop as people age. They found that people with severe hearing loss had on average about half as much aldosterone in their bloodstream as their counterparts with normal hearing. The researchers noted, however, that the levels of aldosterone found in all the participants is considered normal, and that no patients or physicians should consider altering aldosterone levels without more research.

Keyword: Hearing; Hormones & Behavior
Link ID: 8521 - Posted: 02.11.2006

Bruce Bower The concept of identity theft assumes an entirely new meaning for people with brain injuries that rob them of their sense of self—the unspoken certainty that one exists as a person in a flesh—bounded body with a unique set of life experiences and relationships. Consider the man who, after sustaining serious brain damage, insisted that his parents, siblings, and friends had been replaced by look-alikes whom he had never met. Everyone close to him had become a familiar-looking stranger. Another brain-injured patient asserted that his physicians, nurses, and physical therapists were actually his sons, daughters-in-law, and coworkers. He identified himself as an ice skater whom he had seen on a television program. The sense of "I" can also go partially awry. After a stroke had left one of her arms paralyzed, a woman reported that the limb was no longer part of her body. She told a physician that she thought of the arm as "my pet rock." Other patients bequeath their physical infirmities to phantom children. For instance, a woman blinded by a brain tumor became convinced that it was her child who was sick and blind, although the woman had no children. Copyright ©2006 Science Service.

Keyword: Laterality; Attention
Link ID: 8520 - Posted: 06.24.2010

By Jennifer Viegas, Discovery News — Female baboons that suffer the loss of a close friend or relative turn to other baboons for comfort and support, according to a new study that encompassed 14 years of observing over 80 free-ranging baboons in Botswana's Okavango Delta. The study provides the first direct evidence that certain animals mourn the loss of individuals, even when the rest of their social group remains intact. The findings also suggest that friendship may be just as important to some primates as it is for humans. Researchers particularly were struck by the behavior of one female chacma baboon (Papio hamadryas ursinus) named Sylvia, who was described as "the queen of mean" and disdainful of other baboons until she lost her daughter, Sierra, to a lion kill. "In the week after Sierra died, Sylvia was withdrawn," said Anne Engh, who led the project. "When the other females were grooming and socializing, she tended to sit alone and rarely interacted even with her other relatives." Copyright © 2006 Discovery Communications Inc.

Keyword: Emotions; Evolution
Link ID: 8519 - Posted: 06.24.2010

Prashant Nair TWO antibodies that enabled the severed spinal nerves of rats to be regenerated are to be tested in humans. The antibodies have helped rats with damaged spinal cords to walk again, by blocking the action of Nogo, a protein that stops nerve cells sprouting new connections. But there were concerns about whether blocking Nogo would lead to uncontrolled neuronal rewiring in the brain or spinal cord and it was also unclear how such a therapy could be given to humans. Now Martin Schwab and his colleagues at the University of Zurich in Switzerland have infused two antibodies, 11C7 and 7B12, into the damaged spinal cords of rats. An osmotic mini-pump connected to a fine catheter was used to deliver the antibodies directly into the cerebrospinal fluid surrounding the injured part of the spinal cord - a method of delivery that could easily be applied to humans, they say. The antibodies triggered regeneration of axons, the fine thread-like extensions that connect neurons, and enabled injured rats to swim, cross the rungs of a ladder without slipping and traverse a narrow beam (Annals of Neurology, vol 58, p 706). Moreover, the antibodies did not cause hyperalgesia, a condition in which even a simple touch is sensed as pain - a sign that would have indicated wrong neuronal connections had been made. © Copyright Reed Business Information Ltd.

Keyword: Regeneration
Link ID: 8518 - Posted: 06.24.2010

Roxanne Khamsi Colour vision may have evolved in primates to help them pick up on changes in blood and oxygen concentrations beneath the skin’s surface, giving access to emotional cues, a new analysis proposes. Previously research has suggested that primates – the only mammals with the ability to see in colour – evolved this facility to spot ripe fruits or nutritional leaves. The new analysis compared variations in skin colour change with the colour sensitivities of primate vision cells. These cells, known as cones, sit in the retina of the eye and allow primates to discriminate colour. Charting the receptivity of these cells was no small task. “Basically, careful retinal neurophysiologists and psychophysicists spent untold numbers of hours measuring how sensitive each cone is to each wavelength of light,” says Mark Changizi at Caltech in Pasadena, California, US. Changizi, who led the new study, and his colleagues built on this previous research by analysing how different primates’ cone cells might pick up on shifting blood oxygen levels, which show through the skin. © Copyright Reed Business Information Ltd

Keyword: Vision; Emotions
Link ID: 8517 - Posted: 06.24.2010