Rebecca Abrams applauds Sue Gerhardt's clear-sighted assessment of child development in Why Love Matters When researchers studied the brains of Romanian orphans - children who had been left to cry in their cots from birth and denied any chance of forming close bonds with an adult - they found a "virtual black hole" where the orbitofrontal cortex should have been. This is the part of the brain that enables us to manage our emotions, to relate sensitively to other people, to experience pleasure and to appreciate beauty. These children's earliest experiences had greatly diminished their capacity ever to be fully human. Sue Gerhardt's book Why Love Matters shows that early experience has effects on the development of both brain and personality that none of us can afford to ignore. It was Margaret Ainsworth, a Canadian psychologist, who first demonstrated a robust connection between early childhood experience and personality. For a large part of the 1960s Ainsworth sat behind a two-way mirror in Baltimore and watched one-year-olds playing with their mothers. She noted what happened when the mother left the room for a few minutes and how the child responded when she returned. She then took the study a stage further and studied what happened when, instead of the mother, a stranger entered the room and tried to engage with the child. Ainsworth's "Strange Situation" study, together with John Bowlby's attachment theory, showed that how a child developed was not the result of a general mish-mash of experiences, but the direct result of the way the child's main carer responded to and engaged with him or her. A neglectful, stressed or inconsistent parent gave the kind of care which tended to lead to anxious, insecure or avoidant children. Further studies showed that patterns of attachment behaviour in one-year-olds could accurately predict how those children would behave aged five and eight. © Guardian Newspapers Limited 2004

Keyword: Development of the Brain; Emotions
Link ID: 5849 - Posted: 06.24.2010

Nearly 3,000 babies a year die suddenly in their sleep in the U.S., leaving devastated parents wondering what went wrong. Findings published online this week in the Proceedings of the National Academy of Sciences offer insight into the genetic basis of one type of sudden infant death syndrome (SIDS). “This is one of the first genetic sub-classifications of SIDS,” says study leader Dietrich A. Stephan of the Translational Genomics Research Institute (TGen) in Phoenix, Ariz. “And it's going to be helpful in offering parents answers for sudden infant deaths, recognizing predisposition early, and hopefully saving a number of these babies.” The researchers identified children who suffered from a specific form of SIDS known as SIDDT in an Amish community in Pennsylvania. Twenty-one infants from nine families had passed away before the age of one and the scientists analyzed DNA from four of the babies as well as their parents, siblings and close relatives. The researchers identified an alteration in a gene on chromosome 6 called TSPYL: all four children had two abnormal copies of the gene and their parents each carried one copy of the alteration. TSPYL is expressed in the brainstem and sudden deaths may occur because of changes to the brain's regulatory systems that govern cardiac and pulmonary protective reflexes, the team reports. The researchers will next investigate the relationship between TSPYL mutations and SIDS in the general population, as well as the gene's role in controlling breathing and heart rate in premature infants that are otherwise normal. --Sarah Graham © 1996-2004 Scientific American, Inc.

Keyword: Sleep
Link ID: 5848 - Posted: 06.24.2010

MINNEAPOLIS / ST. PAUL—That cardinal singing his heart out in your backyard has ancestors that left the neighborhood of Australia 45 million years ago. A comprehensive study of DNA from songbirds and their relatives shows that these birds, which account for almost half of all bird species, did not originate in Eurasia, as previously thought. Instead, their ancestors escaped from a relatively small area--Australasia (Australia, New Zealand and nearby islands) and New Guinea--about 45 million years ago and went on to populate every other continent save Antarctica. The study, led by Keith Barker of the University of Minnesota's Bell Museum of Natural History, will be published online this week in the journal Proceedings of the National Academy of Sciences. The birds in question belong to the group called Passeriformes, or perching birds. It includes all songbirds, such as robins, cardinals, blackbirds, house sparrows, house finches and crows. The group is further divided into birds that must learn their songs "true songbirds") and those with the innate ability to sing the "correct" song. True songbirds account for 4,580 of the 6,000 known Passeriformes species. (There is a total of 9,702 known species of birds.) The true songbirds are currently divided into two groups: Passerida (3,477 species, among them many familiar backyard species) and Corvida (1,103 species, including crows and ravens). The two groups of true songbirds were thought to have separate origins. The Corvida originated in Australasia, but the Passerida were thought to have arisen separately, in Eurasia. The Passerida then supposedly spread from Eurasia to Africa, Australasia and the New World. But in examining the DNA sequences of two genes in all but one family (a closely related group, such as "crows and jays" or "warblers") of passerine birds, Barker and his colleagues made a startling discovery.

Keyword: Evolution
Link ID: 5847 - Posted: 06.24.2010

For some mice, getting drunk is a lot harder than chugging a few tequila shots. Mice that lack a particular protein receptor take longer than their alcohol-swilling peers to become intoxicated. The results provide a candidate gene for alcoholism and reveal a potential mechanism for how ethanol inebriates animals. No one knows why some people get giddy on a couple drinks while others stay sober, but those who require more libation to start dancing on tables have a higher risk of alcoholism. Alcohol boosts the amount of a brain chemical called adenosine--thought to cause the symptoms of drunkenness, including sedation--which limits the amount of alcohol one can imbibe. Booze increases adenosine by blocking a different protein receptor called ENT1, which normally transports loose adenosine back into the neuron. That means adenosine is free to whip up the woozy adenosine receptors. Chronic exposure to ethanol causes ENT1 receptors to become insensitive to alcohol and go back to cleaning up adenosine. Neurologist Robert Messing and colleagues at the Ernest Gallo Clinic and Research Center, Emeryville, California, wondered if lack of ENT1 from the get-go would make animals more tolerant to alcohol. To find out, they genetically engineered mice to lack both copies of the gene for ENT1. The team then tested their sensitivity to alcohol by injecting the mice with enough alcohol to get them just over the legal limit. Instead of putting them in driver's seat, the researchers placed the animals on a rotating rod to check their balance. Like talented midwestern log-rollers, the mice lacking ENT1 stayed on the rod nearly twice as long as the normal mice. Both types of animals had equivalent blood alcohol levels, indicating the effect was not due to faster metabolism of the ethanol by the mutants, the team reported 18 July online in Nature Neuroscience. Copyright © 2004 by the American Association for the Advancement of Science.

Keyword: Drug Abuse
Link ID: 5846 - Posted: 06.24.2010

- Bethesda, MD -- The toughest among us -- combat soldiers, athletes, or anyone in a high-stress occupation, may claim that they become “hardened” to adversity and defeat. But a new animal study demonstrates that although the body may temporarily adjust to stress, the risk for long-term cardiac problems may be the consequence of daily exposure to confrontation. Even the most self-controlled individual is susceptible to stress, which is the body’s reaction to injurious forces, infections, and various abnormal states that tend to disturb its normal physiological equilibrium. When we exert limited control over environmental stimuli, such physiological and behavioral changes may ultimately produce increased susceptibility to psychosomatic disorders when the brain impacts on bodily functions such as cardiovascular disturbances. Social stressors have been shown to induce robust short-term activations of the sympathetic-adrenomedullary system and the pituitary-adrenocortical axis. As far as cardiovascular responses to social defeat and subordination are concerned, increases in blood pressure and plasma catecholamine levels (the biochemical response to stress) have been documented in rats, persisting as long as the stimulus was present or shortly thereafter. In addition, experimental stress has produced a considerable increase in heart rate. Long-term effects of social challenges on a number of physiological and behavioral parameters have also been reported, mainly involving the daily rhythms of heart rate, body temperature, food intake, and exploratory and social activity. Many animal studies indicate that there is a gradual decline in stress when the stress factor, such as changes in habitation, is repeatedly applied. In other words, the body adapts so there is less stress.

Keyword: Stress
Link ID: 5845 - Posted: 06.24.2010

General human intelligence appears to be based on the volume of gray matter tissue in certain regions of the brain, UC Irvine College of Medicine researchers have found in the most comprehensive structural brain-scan study of intelligence to date. The study also discovered that because these regions related to intelligence are located throughout the brain, a single “intelligence center,” such as the frontal lobe, is unlikely. Dr. Richard Haier, professor of psychology in the Department of Pediatrics and long-time human intelligence researcher, and colleagues at UCI and the University of New Mexico used MRI to obtain structural images of the brain in 47 normal adults who also took standard intelligence quotient tests. The researchers used a technique called voxel-based morphometry to determine gray matter volume throughout the brain which they correlated to IQ scores. Study results appear on the online version of NeuroImage. Previous research had shown that larger brains are weakly related to higher IQ, but this study is the first to demonstrate that gray matter in specific regions in the brain is more related to IQ than is overall size. Multiple brain areas are related to IQ, the UCI and UNM researchers have found, and various combinations of these areas can similarly account for IQ scores. Therefore, it is likely that a person’s mental strengths and weaknesses depend in large part on the individual pattern of gray matter across his or her brain. © Copyright 2002-2004 UC Regents

Keyword: Intelligence
Link ID: 5844 - Posted: 06.24.2010

Good mothering can abolish the impact of a "bad" gene for aggression, suggests a new study, adding spice to the "nature-versus-nurture" controversy. The findings come at a time when governments in Britain and Australia are seeking ways to crack down on antisocial behaviour, and refocus attention on impacts of parenting. The new work, on rhesus monkeys, backs an earlier study in people which gave the same result. "We think the findings are striking in parallel with the human studies," says Stephen Suomi of the US National Institute of Child Health and Human Development in Bethesda, Maryland. Speaking on Monday at a press conference in London to mark the opening of a conference on genes and aggression, Suomi said that his results strongly mirror those of a study in 2002 co-led by Terrie Moffitt of the Institute of Psychiatry at King's College London (Science, vol 297, p851). For 26 years, she and her colleagues followed the fate of 1037 children born in 1972 in Dunedin, New Zealand. They found that children were much more likely to grow up to be aggressive and antisocial if they had inherited a "short" version of a gene called MAOA. It makes monoamine oxidase A, an enzyme which helps to break down neurotransmitters such as serotonin, and was less efficient in the individuals with the "short" version. © Copyright Reed Business Information Ltd.

Keyword: Aggression; Development of the Brain
Link ID: 5843 - Posted: 06.24.2010

Michael Hopkin It might seem a poor substitute for dinner and dancing, but when it comes to wooing the ladies, the jumping spider Habronattus dossenus at least has rhythm. Researchers have recorded for the first time the 'seismic' vibrations that accompany a male's visual display of ardour. "Jumping spiders have very good vision, so people thought they were purely visual," says Damian Elias of Cornell University in Ithaca, New York, who captured the routine on video. Extravagant courtship dances and ornaments are common among the dozens of different Habronattus species. Elias and his colleagues made the discovery by placing a male, together with a tethered female, on a taut nylon surface hooked up to a vibration sensor. As the male displayed to the female, the researchers observed the vibrations and converted them to a sound recording. ©2004 Nature Publishing Group

Keyword: Sexual Behavior; Hearing
Link ID: 5842 - Posted: 06.24.2010

People with mild cognitive impairment (MCI) taking the drug donepezil were at reduced risk of progressing to Alzheimer's disease (AD) for the first 18 months of a 3-year study when compared with their counterparts on placebo, according to a presentation of preliminary data from a recently completed clinical trial supported by the National Institute on Aging (NIA), part of the National Institutes of Health. The reduced risk of progressing from MCI to a diagnosis of AD among participants on donepezil disappeared after 18 months, and by the end of the study, the probability of progressing to AD was the same in the two groups. The study compared donepezil, vitamin E, or placebo in participants with MCI to see whether the drugs might delay or prevent progression to AD. Over the course of the study, among people who did progress to AD, the MCI participants on donepezil averaged 661 days until a diagnosis of AD, a second group on vitamin E averaged 540 days from MCI to AD, and those on placebo averaged 484 days to AD. The study investigators reported a statistically significant effect when donepezil was compared to placebo, but said there was no apparent benefit from vitamin E. The NIA and the scientists conducting the study emphasized that further analyses will be needed to assess the practical, clinical implications of the new data; the study is very complex, and the effects appear time limited. "We will subject the data to considerable scrutiny over the next few months for additional information on whether and, if so, when the drug could benefit people with MCI." said Neil Buckholtz, Ph.D., Chief of the NIA's Dementias of Aging Branch. "Today's presentation of a possible but limited effect of donepezil is encouraging. But we are hoping that further clinical studies in MCI patients will result in more significant progress in delaying a diagnosis of Alzheimer's disease."

Keyword: Alzheimers
Link ID: 5841 - Posted: 07.20.2004

High levels of estrogen found in the most responsive females David Perlman, Chronicle Science Editor A new mystery in the saga of Sausalito's humming toadfish has finally been solved: It's hormones and hearing all the way. For more than 25 years, houseboat dwellers along the Sausalito waterfront have been awakened every summer night by loud humming noises resounding beneath their homes. Even local folk in nearby houses on land complained: They sound like an orchestra full of mournful, rasping oboes, they say. It took five years back in the 1980s for John McCosker, a marine biologist at the California Academy of Sciences, to pin the blame on the mating call of the male plainfin midshipman -- an ugly foot-long creature also called the toadfish but known scientifically as Porichthys notatus -- who nests beneath rocks along the shore and summons willing females to deposit their eggs so the males can fertilize them with sperm. Now a team of aquatic neurobiologists has discovered why some females of the species eagerly spawn near the males, while others literally cannot hear the mating call at all and ignore its loud vibrations completely. ©2004 San Francisco Chronicle

Keyword: Hearing; Sexual Behavior
Link ID: 5840 - Posted: 06.24.2010

By MALCOLM RITTER, AP Science Writer People with a common memory disorder that often leads to Alzheimer's disease (news - web sites) may be able to briefly delay that fate by taking a drug normally prescribed for Alzheimer's, a new study indicates. But ultimately the drug Aricept doesn't cut the risk of getting the feared illness, despite an average delay of six months. The lead author of the study, Dr. Ronald Petersen of the Mayo Clinic, said it was too early to make any recommendations for doctors and patients. He called the new results "a foot in the door" to finding more effective treatments. The same study found no effect from vitamin E, long viewed as a possible weapon against Alzheimer's. The experiment is the first to show that Alzheimer's can be delayed in people with the memory disorder, mild cognitive impairment, Petersen said. So researchers might be able to find other treatments that will produce more than the "modest" effect of Aricept, he said. MCI may be at least as common as Alzheimer's, which afflicts some 4 million Americans. Petersen said it might appear in some 18 percent to 20 percent of people older than 65 who do not have Alzheimer's or other dementia. Most of these people go on to develop Alzheimer's, with about 10 percent to 15 percent receiving an Alzheimer's diagnosis each year, Petersen said. Copyright © 2004 The Associated Press.

Keyword: Alzheimers
Link ID: 5839 - Posted: 06.24.2010

A global research project is aiming to pin down the genetic causes of autism by studying 6,000 DNA samples from families affected by the brain disorder The US National Alliance for Autism Research project involves 170 experts from the US, Canada, the UK and Europe. Researchers will use a new technology called DNA microarray to scan the human genome to locate key genes. UK experts said the research offered "great hope", but added environmental factors were also a likely cause. Over the next six months, the researchers will analyse 6,000 DNA samples from families where two children have an autism spectrum disorder. Their parents' DNA will be analysed as part of the study. The "gene chip" which they are using to carry out the DNA microarray testing contains thousands of strands of synthetic DNA, allowing genetic patterns which are common to the families to be identified. Results from the study, believed to be the largest study into autism genes in history, are likely to be available in early 2005. Autism is a complex brain disorder that often inhibits a person's ability to communicate, respond to surroundings or form relationships with others. There are no specific medical treatments for autism or a cure. Around 535,000 people in the UK have an autism spectrum disorder. (C)BBC

Keyword: Autism
Link ID: 5838 - Posted: 07.19.2004

ATLANTA- Difficulties in performing more challenging cognitive tasks, such as managing one's finances and medications, preparing meals and traveling independently, could be early warning signs that indicate the presence of mild cognitive impairment (MCI), according to Emory University researchers. Other more basic and well-rehearsed daily tasks, such as bathing, grooming, and dressing, can also decline in patients with MCI, but to a lesser extent. The findings will be presented at the 9th International Conference of Alzheimer's Disease and Related Disorders in Philadelphia on July 18 at 8 a.m. MCI is a term described as a subtle decline in thinking abilities. A person with MCI, for example, may experience memory problems greater than normally expected with aging, but that person does not show other symptoms of dementia, such as impaired judgment or reasoning, according to the Alzheimer's Association. Little research has been conducted on whether well-rehearsed activities of daily living, known as ADLs (feeding, dressing, grooming, walking, bathing and toileting) and instrumental activities of daily living, known as IADLs, (laundry, shopping, transportation, driving, meal preparation, managing medications and finances) are compromised early in the disease process.

Keyword: Alzheimers
Link ID: 5837 - Posted: 07.19.2004

Obese people who undergo gastric bypass surgery may lose weight quickly because levels of a hormone controlling appetite fall away, research shows. The hormone, ghrelin, is released into the blood from the stomach and upper intestine and triggers hunger pangs. It is one of two-dozen hormones thought to help regulate hunger. The Archives of Surgery study, by Atlanta's Emory University, found ghrelin levels dropped by nearly one-third after gastric bypass surgery. The researchers focused on a particular type of gastric bypass surgery known as the Roux-en-Y procedure. This involves dividing the stomach to create a pouch that is attached to the small intestine. It reduces the size of the stomach and bypasses parts of the gastric system that absorb food and may trigger releases of the hormone. However, it is considered to be risky and is usually only offered to patients who are severely overweight and who have been unable to lose weight using other methods. The researchers checked levels of the hormone in 48 obese patients, 34 of whom had undergone gastric bypass surgery. Another eight obese patients had other types of weight-loss procedures that did not divide the stomach, and six non-obese patients undergoing surgery were monitored to provide a base level of the hormone. None of these 14 patients showed any reduction in ghrelin levels. (C)BBC

Keyword: Obesity
Link ID: 5836 - Posted: 07.18.2004

By ANAHAD O'CONNOR Dr. Loren R. Mosher, a former National Institute of Mental Health official who developed a drug-free approach to treating schizophrenia and argued that psychiatrists should rely less heavily on antipsychotic medications, died on July 10 at a clinic in Berlin. He was 70. The cause was liver disease, his wife, Judith Schreiber, said. In the 1960's and 70's, as psychiatrists were beginning to prescribe powerful new antipsychotic drugs to treat schizophrenia, Dr. Mosher advocated using little-known alternative therapies instead. From 1968 to 1980, while chief of the Center for Studies of Schizophrenia at the mental health institute, he began a long-term study that compared drug-free treatments with conventional hospitalization. Through decades of research, he found that patients who were randomly assigned to live in a psychotherapeutic, residential setting with few medications did just as well as patients given drugs. In some cases, when the person had never taken any medication, he found the outcome was even better. "Loren believed that you couldn't just give drugs to someone who is in deep distress and ignore them," said Dr. David Cohen, a professor of social work at the School of Social Work at Florida International University and a former colleague of Dr. Mosher. "He said that there was therapeutic value in just being with someone and bearing the discomfort of it. Just giving the patients drugs would only distance yourself from them." Copyright 2004 The New York Times Company

Keyword: Schizophrenia
Link ID: 5835 - Posted: 07.18.2004

By LISA BELKIN When Vivienne Sales finally broke her silence, she did so loudly, losing her temper in the hushed library where she worked. It was August 2003, and she had been hanging on to her job as a reference librarian by the most fragile of threads. For more than a year her supervisors at the Embry-Riddle Aeronautical University in Prescott, Ariz., had been warning her that she was sometimes sloppy and inaccurate. She was late for work too often, they said. She didn't dress neatly and appropriately. Her desk was always a mess. Sales knew all this. She also knew why. Three years earlier, when she was 36, she was told she had attention-deficit and hyperactivity disorder. (That's the full name of the condition, and while its initials are technically a.d.h.d., not all who have it exhibit the hyperactivity symptoms, so it is often referred to conversationally as simply A.D.D.) The news was a relief because it seemed to explain everything -- why she rarely seemed to fit into a workplace, why she left nine different jobs in 1999 alone, why, despite two master's degrees and years of dogged hard work, she never seemed to get anywhere. Although the diagnosis was illuminating, Sales was determined to keep her condition to herself. ''Work isn't like school, where they have to give you more time on the tests'' if you have A.D.D., she explained. ''In the real world, if you tell during the interview, they won't hire you. And if you tell after you're hired, they can fire you.'' Copyright 2004 The New York Times Company

Keyword: ADHD
Link ID: 5834 - Posted: 07.18.2004

By WALTER KIRN One of the least persuasive doctrines of the religion I belonged to as a teenager held that temptation was a gift from God because doing right would have no meaning if people lacked the freedom to do wrong. The idea, as I understood it at the time, was that even though it would be a sin to pick up a pretty girl at the church dance and drive her to the dark abandoned chicken farm known as ''the coop'' where we Mormon kids held our makeout sessions, I should nevertheless feel grateful for the fact that I desperately desired to do so. Except I didn't feel grateful; I felt confused. That good actions often felt deeply frustrating and bad actions supremely pleasurable seemed to me to be creation's greatest flaw, not its crowning virtue. My old confusion came back to me when I read a recent series of articles in the science journal Nature concerning the genetic and chemical roots of sexual behavior in the vole. The study in question involved the prairie vole, a rodent species whose males are naturally monogamous and enjoy spending time with their partners, and the meadow vole, whose males prefer to mate with many females and then like to wander off and be alone. What could account for this difference, the scientists wondered, between the two groups of closely related creatures? And could the naughty, randy voles be civilized? Yes, it turned out, they could be. It wasn't hard, in fact. To make the meadow voles act like prairie voles when it came to so-called pair bond formation, the researchers merely injected a gene harvested from the ideal-husband voles into the forebrains of the rock-star voles. (The forebrain is the seat of passion? Who knew?) Copyright 2004 The New York Times Company

Keyword: Sexual Behavior; Hormones & Behavior
Link ID: 5833 - Posted: 07.18.2004

A vitamin found in a range of common foods could protect against Alzheimer's Disease, researchers have claimed. A team from the Chicago Institute for Healthy Aging found niacin - vitamin B3 - was also linked to a reduced risk of age-related mental decline. It is found in dairy products, poultry, fish, lean meats, nuts, and eggs. The team said their findings, published in the Journal of Neurosurgery and Psychiatry, could help prevent Alzheimer's developing. The US researchers looked at the diets of almost 4,000 people aged 65 and over between 1993 and 2002. None had any history of Alzheimer's disease. The researchers then monitored for any signs of decreasing mental agility. After three years, a sample of 815 people were checked for clinical changes and their dietary intake was assessed. Among this group, 131 were diagnosed with Alzheimer's disease. The researchers, led by Dr Martha Morris took into account other risk factors such as age, gender, race, educational levels and a gene known as the ApoE. They found that those with the lowest food intake of niacin - around 12.6mg a day - were 80% more likely to be diagnosed with Alzheimer's than those with the highest intake - around 22.4mg a day. When they examined the mental agility of the larger group after six years, the researchers found cognitive decline was "significantly reduced" by 44% among those with the highest niacin intake compared with those with the lowest intake. (C)BBC

Keyword: Alzheimers
Link ID: 5832 - Posted: 07.17.2004

By ERIC NAGOURNEY This time of year dermatologists are wringing their pale, smooth hands in dismay and frustration: Why don't people listen to the warnings about the risks of sunlight? Vanity and the recklessness of the young usually get the blame. But maybe there's more to the urge to bake than looks and youthful abandon. A small, provocative study seems to say so. It links the penetration of ultraviolet rays to the release of pleasure-inducing endorphins in the brain. Writing in The Journal of the American Academy of Dermatology, a group of researchers reported that they sought out volunteers who regularly went to tanning salons and invited them to lounge in tanning beds at no charge over a period of six weeks. The 14 volunteers - 13 women and a man - came in twice a week and were directed to one of two seemingly identical tanning beds. But one of the beds was equipped with a UV filter and the other wasn't. When the volunteers were given mood assessments afterwards, those who had not been shielded from the ultraviolet light consistently seemed more content and more relaxed. And when the group was given the opportunity to come in on a third day and choose one bed or the other, 11 of the 12 people headed straight for the bed that provided ultraviolet light. Copyright 2004 The New York Times Company

Keyword: Drug Abuse; Biological Rhythms
Link ID: 5831 - Posted: 07.17.2004

Infant pacification may have led to the origins of language By Kate Wong When a staff member brings a baby into the offices of Scientific American, a small crowd inevitably forms around the infant, and although the onlookers all have rather different personalities and mannerisms, they tend to talk to the baby in the same singsong way. Vowels are lingered over, phrases are repeated in high-pitched voices, and questions carry exaggerated inflections. Sound familiar? This is motherese, the distinctive speech that human adults across the globe instinctively use when addressing babies. And according to a new theory, it holds a key to the emergence of language. In a paper slated for the August Behavioral and Brain Sciences, Florida State University physical anthropologist Dean Falk proposes that just as motherese forms the scaffold for language acquisition during child development, so, too, did it underpin the evolution of language. Such baby talk itself originated, she posits, as a response to two other hallmarks of human evolution: upright walking and big brains. In contrast to other primates, humans give birth to babies that are relatively undeveloped. Thus, whereas a chimpanzee infant can cling to its quadrupedal mother and ride along on her belly or back shortly after birth, helpless human babies must be carried everywhere by their two-legged caregivers. Assuming, as many anthropologists do, that early humans had chimplike social structures, moms did most of the child rearing. But having to hold on to an infant constantly would have significantly diminished their foraging efficiency, Falk says. She argues that hominid mothers therefore began putting their babies down beside them while gathering and processing food. To placate an infant distressed by this separation, mom would offer vocal, rather than physical, reassurance and continue her search for sustenance. © 1996-2004 Scientific American, Inc.

Keyword: Language
Link ID: 5829 - Posted: 06.24.2010