by Aviva Rutkin Eureka! Like Archimedes in his bath, crows know how to displace water, showing that Aesop's fable The Crow and the Pitcher isn't purely fictional. To see if New Caledonian crows could handle some of the basic principles of volume displacement, Sarah Jelbert at the University of Auckland in New Zealand and her colleagues placed scraps of meat just out of a crow's reach, floating in a series of tubes that were part-filled with water. Objects potentially useful for bringing up the water level, like stones or heavy rubber erasers, were left nearby. The crows successfully figured out that heavy and solid objects would help them get a treat faster. They also preferred to drop objects in tubes where they could access a reward more easily, picking out tubes with higher water levels and choosing tubes of water over sand-filled ones. However, the crows failed at more challenging tasks that required an understanding of the effect of tube width or the ability to infer a hidden connection between two linked tubes. The crows displayed reasoning skills equivalent to an average 5 to 7 year old human child, the researchers claim. Previously, Eurasian jays have shown some understanding of water displacement, as have chimpanzees and orang-utans, but using similar experiments could assess and compare their skill levels. "Any animal capable of picking up stones could potentially participate," write the researchers. © Copyright Reed Business Information Ltd.

Related chapters from BN: Chapter 1: Introduction: Scope and Outlook; Chapter 6: Evolution of the Brain and Behavior
Related chapters from MM:Chapter 20:
Link ID: 19413 - Posted: 03.27.2014

Matt Kaplan Humans are among the very few animals that constitute a threat to elephants. Yet not all people are a danger — and elephants seem to know it. The giants have shown a remarkable ability to use sight and scent to distinguish between African ethnic groups that have a history of attacking them and groups that do not. Now a study reveals that they can even discern these differences from words spoken in the local tongues. Biologists Karen McComb and Graeme Shannon at the University of Sussex in Brighton, UK, guessed that African elephants (Loxodonta africana) might be able to listen to human speech and make use of what they heard. To tease out whether this was true, they recorded the voices of men from two Kenyan ethnic groups calmly saying, “Look, look over there, a group of elephants is coming,” in their native languages. One of these groups was the semi-nomadic Maasai, some of whom periodically kill elephants during fierce competition for water or cattle-grazing space. The other was the Kamba, a crop-farming group that rarely has violent encounters with elephants. The researchers played the recordings to 47 elephant family groups at Amboseli National Park in Kenya and monitored the animals' behaviour. The differences were remarkable. When the elephants heard the Maasai, they were much more likely to cautiously smell the air or huddle together than when they heard the Kamba. Indeed, the animals bunched together nearly twice as tightly when they heard the Maasai. “We knew elephants could distinguish the Maasai and Kamba by their clothes and smells, but that they can also do so by their voices alone is really interesting,” says Fritz Vollrath, a zoologist at the University of Oxford, UK (see video below). © 2014 Nature Publishing Group

Related chapters from BN: Chapter 19: Language and Lateralization; Chapter 6: Evolution of the Brain and Behavior
Related chapters from MM:Chapter 15: Language and Lateralization
Link ID: 19349 - Posted: 03.11.2014

Sara Reardon Freddie Lee Hall loved to gamble, although he usually lost. Winning was better: then he gladly gave the money back to the friends he'd won it from, along with all the wages he earned picking fruit in rural Florida. His friends praised him for this. It made him feel good. And Hall needed to feel good — as court documents make abundantly clear. As a child growing up in the impoverished town of Webster, Florida, he had struggled to keep up with 16 brothers and sisters, who were much smarter than he was. If he failed to understand something, his mother beat him, once while he was tied up in a bag strung over a fire. He stuttered, never learned to read and feared the dark. He was unable to live alone. “Even though he was full grown, mentally he was a child,” his sister Diana told the court. “I had hoped to protect Freddie Lee from the outside world.” But the outside world found him. In 1978, Hall and his friend Mack Ruffin decided to rob a convenience store. They needed a car, so they forced 21-year-old Karol Hurst, who was pregnant, to drive into the woods, where they raped and killed her. Later, one of the pair also shot and killed a sheriff's deputy. When the two men were caught, tried and convicted of murder, the court decided that Hall was the likely ringleader. Ruffin was eventually sentenced to life in prison; Hall was sentenced to death. Next month, after 35 years of failed appeals to have that death sentence commuted to life imprisonment, Hall will have his case heard before the US Supreme Court. His guilt is not in question: the issue is Florida's use of IQ test scores in sentencing him to death. © 2014 Nature Publishing Group,

Related chapters from BN: Chapter 18: Attention and Higher Cognition; Chapter 16: Psychopathology: Biological Basis of Behavior Disorders
Related chapters from MM:Chapter 14: Attention and Higher Cognition; Chapter 12: Psychopathology: The Biology of Behavioral Disorders
Link ID: 19285 - Posted: 02.24.2014

By Roy H. Hamilton and Jihad Zreik It's hard to imagine anyone, no matter how brilliant, who doesn't yearn to be even smarter. Thanks to recent advances in neural science, that wish may come true. Researchers are finding ways to rev up the human brain like never before. There would be just one question: Do we really want to inhabit that world? It may be too late to ask. Modern society has already embraced the basic idea of fine-tuning our intellects via artificial procedures—what might be termed “cosmetic” neurology. Schoolchildren take Adderall, Concerta and other attention-focusing medications. Parents and teachers rely on antidepressants and antianxiety drugs. And self-help books offer the latest advances in neuroscience to help ordinary people think faster and sharper. Add to those advances another cognitive-enhancement method: transcranial direct-current stimulation (tDCS). With this technique, electrodes applied to the scalp deliver minuscule amperages of current to the brain. This trickle of electricity seems to cause incremental adjustments in the electrical potentials of membranes in the neurons closest to the electrodes, increasing or decreasing their likelihood of firing. And that, in turn, induces measurable changes in memory, language, mood, motor function, attention and other cognitive domains. Investigators still aren't sure whether tDCS can cause long-term neural changes. Although most tests show only transient effects, there is limited evidence that repeated applications might have more persistent results. The procedure is not approved by the U.S. Food and Drug Administration, and the consensus among experts is that it should be performed only under qualified supervision. Nevertheless, if used properly, it is safe, portable, easy to implement and inexpensive. © 2014 Scientific American

Related chapters from BN: Chapter 17: Learning and Memory; Chapter 18: Attention and Higher Cognition
Related chapters from MM:Chapter 13: Memory and Learning; Chapter 14: Attention and Higher Cognition
Link ID: 19242 - Posted: 02.12.2014

| by Isaac Saul Multi-step puzzles can be difficult for humans, but what if I told you there was a bird that could solve them on its own? In this BBC special, Dr. Alex Taylor has set up an eight-step puzzle to try and stump one of the smartest crows he's seen in captivity. They describe the puzzle as "one of the most complex tests of the animal mind ever." This isn't the first time crows' intelligence has been tested, either. Along with being problem solvers, these animals have an eerie tendency towards complex human-like memory skills. Through several different studies, we've learned that crows can recognize faces, communicate details of an event to each other and even avoid places they recognize as dangerous. This bird, dubbed "007" for its crafty mind, flies into the caged puzzle and spends only seconds analyzing the puzzle before getting down to business. Despite the puzzle's difficulty, the bird only seems to be stumped momentarily. At the end of the puzzle is a food reward, but how he gets there is what will really blow your mind. © 2014 TheHuffingtonPost.com, Inc

Related chapters from BN: Chapter 17: Learning and Memory; Chapter 6: Evolution of the Brain and Behavior
Related chapters from MM:Chapter 13: Memory and Learning
Link ID: 19219 - Posted: 02.08.2014

Ian Sample, science correspondent Differences in children's exam results at secondary school owe more to genetics than teachers, schools or the family environment, according to a study published yesterday. The research drew on the exam scores of more than 11,000 16-year-olds who sat GCSEs at the end of their secondary school education. In the compulsory core subjects of English, maths and science, genetics accounted for on average 58% of the differences in scores that children achieved. Grades in the sciences, such as physics, biology and chemistry, were more heritable than those in humanities subjects, such as art and music, at 58% and 42% respectively. The findings do not mean that children's performance at school is determined by their genes, or that schools and the child's environment have no influence. The overall effect of a child's environment – including their home and school life – accounted for 36% of the variation seen in students' exam scores across all subjects, the study found. "The question we are asking is why do children differ in their GCSE scores? People immediately think it's schools. But if schools accounted for all the variance, then children in one classroom would all be the same," said Robert Plomin, an expert in behavioural genetics who led the study at King's College London. To tease out the genetic contribution to children's school grades, the researchers studied GCSE scores of identical twins (who share 100% of their genes) and non-identical twins (who share on average half of the genes that normally vary between people). Both groups share their environments to a similar extent. © 2013 Guardian News and Media Limited

Related chapters from BN: Chapter 7: Life-Span Development of the Brain and Behavior; Chapter 1: Introduction: Scope and Outlook
Related chapters from MM:Chapter 4: Development of the Brain; Chapter 20:
Link ID: 19027 - Posted: 12.12.2013

by Sarah Zielinski If you put two birds together and gave them a problem, would they be any better at solving it than if they were alone? A study in Animal Behaviour of common mynas finds that not only are they no better at problem solving when in a pair than when on their own, the birds actually get a lot worse when put in a group. Andrea S. Griffin and her research team from the University of Newcastle in Callaghan, Australia, began by using dog food pellets as bait to capture common mynas (a.k.a. the Indian mynah, Acridotheres tristis) from around Newcastle. Then they gave each of the birds an innovation test, consisting of a box containing a couple of drawers and some Petri dishes. To get to the food hidden in spots in the box, the birds would have to get creative and figure out how to open one of the four containers by doing things like levering up a lid or pushing open a drawer. The scientists then ranked the birds by innovative ability before pairing them up. Half the pairs consisted of a high-innovation and a low-innovation myna, and the other half were pairs of medium-innovation birds. Then the pairs each received an innovation test similar to the one with boxes. Another experiment tested the birds in same-sex groups of five. On their own, 29 of 34 birds were able to access at least one container. But in pairs, only 15 of the 34 birds did so, and they took a lot longer. Performance dropped for both high- and medium-innovation birds, and it didn’t improve for the low-ranked ones, which had done so poorly the first time around that their results couldn’t get any worse. In groups of five, birds’ results fell even further: No mynas solved any of those tasks. © Society for Science & the Public 2000 - 2013

Related chapters from BN: Chapter 17: Learning and Memory; Chapter 6: Evolution of the Brain and Behavior
Related chapters from MM:Chapter 13: Memory and Learning
Link ID: 18900 - Posted: 11.09.2013

By Scott Barry Kaufman One of the longest standing assumptions about the nature of human intelligence has just been seriously challenged. According to the traditional “investment” theory, intelligence can be classified into two main categories: fluid and crystallized. Differences in fluid intelligence are thought to reflect novel, on-the-spot reasoning, whereas differences in crystallized intelligence are thought to reflect previously acquired knowledge and skills. According to this theory, crystallized intelligence develops through the investment of fluid intelligence in a particular body of knowledge. As far as genetics is concerned, this story has a very clear prediction: In the general population– in which people differ in their educational experiences– the heritability of crystallized intelligence is expected to be lower than the heritability of fluid intelligence. This traditional theory assumes that fluid intelligence is heavily influenced by genes and relatively fixed, whereas crystallized intelligence is more heavily dependent on acquired skills and learning opportunities. But is this story really true? In a new study, Kees-Jan Kan and colleagues analyzed the results of 23 independent twin studies conducted with representative samples, yielding a total sample of 7,852 people. They investigated how heritability coefficients vary across specific cognitive abilities. Importantly, they assessed the “Cultural load” of various cognitive abilities by taking the average percentage of test items that were adjusted when the test was adapted for use in 13 different countries. © 2013 Scientific American

Related chapters from BN: Chapter 7: Life-Span Development of the Brain and Behavior; Chapter 1: Introduction: Scope and Outlook
Related chapters from MM:Chapter 4: Development of the Brain; Chapter 20:
Link ID: 18821 - Posted: 10.22.2013

by Jack Flanagan Although dogs are said to be man's best friend, it doesn't mean they "get" us. At least, not like elephants seem to. Without any training, the giant herbivores can understand and follow our hand gestures – the first non-human animals known to be able to do so. Elephants have lived alongside humans for between 4000 and 8000 years. Despite their potential to be tamed, though, elephants have never been domesticated in the same way as dogs, cats and agricultural animals have. This hasn't prevented them from developing a number of human-like skills. In the wild, they are famously empathetic towards one another. In captivity, elephants have displayed a degree of self-awareness by being able to recognise themselves in a mirrorMovie Camera. Others have developed the teamwork necessary to coordinate and complete a task. In fact, one elephant has even learned some basic phrases in Korean – and another has been taught to paint by its parents. Arguably it was only a matter of time before they added another skill to their impressive repertoire. Hidden talent Pointing gestures are common enough among humans: from an early age babies naturally recognise the meaning behind them. We know that chimpanzees and even seals can do this too, but not without hours of training. It comes as a surprise, then, to discover that elephants can find hidden food once it is pointed out to them – without any prior lessons. © Copyright Reed Business Information Ltd.

Related chapters from BN: Chapter 6: Evolution of the Brain and Behavior; Chapter 1: Introduction: Scope and Outlook
Related chapters from MM:Chapter 20:
Link ID: 18780 - Posted: 10.12.2013

By Justin Gregg Santino was a misanthrope with a habit of pelting tourists with rocks. As his reputation for mischief grew, he had to devise increasingly clever ways to ambush his wary victims. Santino learned to stash his rocks just out of sight and casually stand just a few feet from them in order to throw off suspicion. At the very moment that passersby were fooled into thinking that he meant them no harm, he grabbed his hidden projectiles and launched his attack. Santino was displaying an ability to learn from his past experiences and plan for future scenarios. This has long been a hallmark of human intelligence. But a recently published review paper by the psychologist Thomas Zentall from the University of Kentucky argues that this complex ability should no longer be considered unique to humans. Santino, you see, is not human. He’s a chimpanzee at Furuvik Zoo in Sweden. His crafty stone-throwing escapades have made him a global celebrity, and also caught the attention of researchers studying how animals, much like humans, might be able to plan their behavior. Santino is one of a handful of animals that scientists believe are showing a complex cognitive ability called episodic memory. Episodic memory is the ability to recall past events that one has the sense of having personally experienced. Unlike semantic memory, which involves recalling simple facts like “bee stings hurt,” episodic memory involves putting yourself at the heart of the memory; like remembering the time you swatted at a bee with a rolled up newspaper and it got angry and stung your hand. © 2013 Scientific American

Related chapters from BN: Chapter 6: Evolution of the Brain and Behavior; Chapter 1: Introduction: Scope and Outlook
Related chapters from MM:Chapter 20:
Link ID: 18764 - Posted: 10.09.2013

By John Horgan Last spring, I kicked up a kerfuffle by proposing that research on race and intelligence, given its potential for exacerbating discrimination, should be banned. Now Nature has expanded this debate with “Taboo Genetics.” The article “looks at four controversial areas of behavioral genetics”—intelligence, race, violence and sexuality—”to find out why each field has been a flashpoint, and whether there are sound scientific reasons for pursuing such studies.” Behavioral genetics has failed to produce robust evidence linking complex traits and disorders to specific genes. The essay provides a solid overview, including input from both defenders of behavioral genetics and critics. The author, Erika Check Hayden, quotes me saying that research on race and intelligence too often bolsters “racist ideas about the inferiority of certain groups, which plays into racist policies.” I only wish that Hayden had repeated my broader complaint against behavioral genetics, which attempts to explain human behavior in genetic terms. The field, which I’ve been following since the late 1980s, has a horrendous track record. My concerns about the potential for abuse of behavioral genetics are directly related to its history of widely publicized, erroneous claims. I like to call behavioral genetics “gene whiz science,” because “advances” so often conform to the same pattern. Researchers, or gene-whizzers, announce: There’s a gene that makes you gay! That makes you super-smart! That makes you believe in God! That makes you vote for Barney Frank! The media and the public collectively exclaim, “Gee whiz!” © 2013 Scientific American

Related chapters from BN: Chapter 1: Introduction: Scope and Outlook; Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 20: ; Chapter 4: Development of the Brain
Link ID: 18753 - Posted: 10.07.2013

Smart, successful, and well-connected: a good description of Albert Einstein … and his brain. The father of relativity theory didn’t live to see modern brain imaging techniques, but after his death his brain was sliced into sections and photographed. Now, scientists have used those cross-sectional photos to reveal a larger-than-average corpus callosum—the bundle of nerve fibers connecting the brain’s two hemispheres. Researchers measured the thickness of the famous noggin’s corpus callosum (the lighter-colored, downward-curving region at the center of each hemisphere, above) at various points along its length, and compared it to MRIs from 15 elderly men and 52 young, healthy ones. The thickness of Einstein’s corpus callosum was greater than the average for both the elderly and the young subjects, the team reported online last week in the journal Brain. The authors posit that in Einstein’s brain, more nerve fibers connected key regions such as the two sides of the prefrontal cortex, which are responsible for complex thought and decision-making. Combined with previous evidence that parts of the physicist’s brain were unusually large and intricately folded, the researchers suggest that this feature helps account for his extraordinary gifts. © 2013 American Association for the Advancement of Science

Related chapters from BN: Chapter 1: Introduction: Scope and Outlook; Chapter 19: Language and Lateralization
Related chapters from MM:Chapter 20: ; Chapter 15: Language and Lateralization
Link ID: 18750 - Posted: 10.07.2013

Daniel Cressey A few chance encounters hundreds of metres underwater seem to have solved the long-standing mystery of what one squid species does with its unusual tentacles: it pretends they are fish to lure its prey into range. Until now, the deep-sea-dwelling squid Grimalditeuthis bonplandi had never been observed in the wild by researchers, and most of the knowledge about it came from partially digested specimens pulled from the stomachs of large fish and whales. Most squid have a pair of tentacles with hooks or suckers that they use to grasp food, but in this species the corresponding tentacles are thin, fragile things — and their function has puzzled squid researchers. Henk-Jan Hoving, a squid researcher at the Helmholtz Centre for Ocean Research in Kiel, Germany, and his team obtained videos of seven of these animals seen in the Atlantic and North Pacific. One of the observations came from an expedition run by the Monterey Bay Aquarium Research Institute in Moss Landing, California, and the other videos were made by commercial remotely-operated submersibles used by the oil and gas industry, and later supplied to Hoving and his team. Hoving and his team saw the squid move the ends of their unique appendages, known as tentacle clubs, in a way that “really looked like a small fish or squid”, he says. They describe their observations in Proceedings of the Royal Society B1. The movement of these tentacles attracts the crustaceans and other cephalopods that G. bonplandi eats. Thinking they are going to get dinner, the prey species move towards the flapping arms, only to be eaten themselves. © 2013 Nature Publishing Group

Related chapters from BN: Chapter 1: Introduction: Scope and Outlook; Chapter 6: Evolution of the Brain and Behavior
Related chapters from MM:Chapter 20:
Link ID: 18572 - Posted: 08.28.2013

By Harvey Black The intelligence of the corvid family—a group of birds that includes crows, ravens, magpies, rooks and jackdaws—rivals that of apes and dolphins. Recent studies are revealing impressive details about crows' social reasoning, offering hints about how our own interpersonal intelligence may have evolved. One recent focus has been on how these birds respond to the sight of human faces. For example, crows take to the skies more quickly when an approaching person looks directly at them, as opposed to when an individual nears with an averted gaze, according to a report by biologist Barbara Clucas of Humboldt State University and her colleagues in the April issue of Ethology. The researchers walked toward groups of crows in three locations in the Seattle area, with their eyes either on the birds or on some point in the distance. The crows scattered earlier when the approaching person was looking at them, unlike other animals that avoid people no matter what a person is doing. Clucas speculates that ignoring a human with an averted gaze is a learned adaptation to life in the big city. Indeed, many studies have shown that crows are able to learn safety behaviors from one another. For example, John Marzluff of the University of Washington (who co-authored the aforementioned paper with Clucas) used masked researchers to test the learning abilities of crows. He and his colleagues ventured into Seattle parks wearing one of two kinds of masks. The people wearing one kind of mask trapped birds; the others simply walked by. Five years later the scientists returned to the parks with their masks. The birds present at the original trapping remembered which masks corresponded to capturing—and they passed this information to their young and other crows. All the crows responded to the sight of a researcher wearing a trapping mask by immediately mobbing the individual and shrieking. © 2013 Scientific American

Related chapters from BN: Chapter 1: Introduction: Scope and Outlook; Chapter 6: Evolution of the Brain and Behavior
Related chapters from MM:Chapter 20:
Link ID: 18563 - Posted: 08.27.2013

By DAVID CRARY, AP National Writer NEW YORK (AP) — There's extensive evidence that pigs are as smart and sociable as dogs. Yet one species is afforded affection and respect; the other faces mass slaughter en route to becoming bacon, ham and pork chops. Seeking to capitalize on that discrepancy, animal-welfare advocates are launching a campaign called The Someone Project that aims to highlight research depicting pigs, chickens, cows and other farm animals as more intelligent and emotionally complex than commonly believed. The hope is that more people might view these animals with the same empathy that they view dogs, cats, elephants, great apes and dolphins. "When you ask people why they eat chickens but not cats, the only thing they can come up with is that they sense cats and dogs are more cognitively sophisticated that then species we eat — and we know this isn't true," said Bruce Friedrich of Farm Sanctuary, the animal-protection and vegan-advocacy organization that is coordinating the new project. "What it boils down to is people don't know farm animals the way they know dogs or cats," Friedrich said. "We're a nation of animal lovers, and yet the animals we encounter most frequently are the animals we pay people to kill so we can eat them." The lead scientist for the project is Lori Marino, a lecturer in psychology at Emory University who has conducted extensive research on the intelligence of whales, dolphins and primates. She plans to review existing scientific literature on farm animals' intelligence, identify areas warranting new research, and prepare reports on her findings that would be circulated worldwide via social media, videos and her personal attendance at scientific conferences. © 2013 Hearst Communications Inc.

Related chapters from BN: Chapter 6: Evolution of the Brain and Behavior; Chapter 1: Introduction: Scope and Outlook
Related chapters from MM:Chapter 20:
Link ID: 18417 - Posted: 07.29.2013

Josh Howgego Thresher sharks can use their lengthy tail fins to swat sardines from shoals, researchers have found by taking underwater footage. Such tactical use of the tail fin during hunting — which was previously observed only in mammals such as dolphins and killer whales1 — might indicate that sharks are more intelligent than scientists thought. Pelagic thresher sharks (Alopias pelagicus) are nocturnal and notoriously shy. Researchers have long suspected that the shark uses its tail — which makes up half of its body length — to stun its prey, but the behaviour has not been documented before under natural conditions2. Simon Oliver, lead investigator of the Thresher Shark Research and Conservation Project, and his colleagues studied the sharks off the coast of Cebu, an island in the Philippines. Oliver, who is based at the University of Liverpool, UK, has been watching the animals during the day since 2005, but he hadn’t seen the sharks hunting until some divers saw it happening and phoned him. “Immediately I dropped everything and went to investigate,” he says. The sharks hunt by first lunging into a school of fish, priming their tails as they move in. They then swipe the tail in a trebuchet-like motion through an arc of 180o in just one-third of a second — fast enough to both physically hit the fish and to create a stunning shock wave (see image below). Each strike can take out up to seven sardines, so Oliver thinks it is probably the most energy-efficient way for the animals to hunt. The team published the results today in PLOS ONE3. © 2013 Nature Publishing Group

Related chapters from BN: Chapter 1: Introduction: Scope and Outlook; Chapter 6: Evolution of the Brain and Behavior
Related chapters from MM:Chapter 20:
Link ID: 18367 - Posted: 07.11.2013

By Felicity Muth Pigs are one of the top animals consumed across the world. According to the US Census Bureau, in 2010, around one hundred million metric tons of pork were consumed that year, with 10% of this being in the US (although it does seem that overall meat consumption is declining). With so many of us eating pork, you might think we’d know a bit more about these animals. A lot of people are surprised to hear about some of the cognitive abilities of the average pig. While it’s problematic to call an animal ‘intelligent’ or not, as this is a term is ill-defined and too often related to human cognition, pigs have shown us that they have a number of cognitive abilities tested across many different types of test. They have good learning and memory in many contexts (both short- and long-term), including episodic memory (memory for past events in their life), the ability to differentiate between familiar and unfamiliar pigs, and an inclination to explore novel objects. In addition to these behavioural feats, the pig brain is well-developed. For example, the volume of the prefrontal cortex is around 24% of the total neocortex and 10% of the total brain volume, comparable to primates including humans. I’m not sure why, despite this research, pigs have a reputation for being ‘stupid’. Similar to the ‘three-second memory’ myth with fish, I wonder if it’s perpetuated to make people not feel bad about eating these animals, or the conditions under which they are often reared. © 2013 Scientific American

Related chapters from BN: Chapter 1: Introduction: Scope and Outlook; Chapter 6: Evolution of the Brain and Behavior
Related chapters from MM:Chapter 20:
Link ID: 18259 - Posted: 06.12.2013

by Debora MacKenzie YOUR eye colour is a product of your DNA, but what about your IQ? The biggest-ever search for genes that affect intelligence, and the first to give reproducible results, has found 10 variations in DNA that seem to influence intelligence – but not by much. Studies of families show intelligence is 40 to 50 per cent inherited, and otherwise depends on environment. Since mass-analysis of DNA variations became possible, a number of studies have sought the genes involved in this inheritance, and some papers have claimed strong associations between particular genes and IQ. Yet results have varied widely and none have been replicated. "Many of the published findings of the last decade are wrong," says John Hewitt of the University of Colorado in Boulder, who was not involved in the new study. So if intelligence is inherited, where are the genes hiding? The research may have hit problems because each gene linked with IQ has only a tiny effect on overall intelligence. This means you need data on a large number of people to reliably distinguish such effects from measurement error. Most studies have involved between 100 and 2000 subjects. Now, some 200 researchers have assembled 54 sets of data on more than 126,000 people who have had their genomes analysed for 2.5 million common, small mutations called SNPs. Information was also available for how long they spent in education and the level they reached. © Copyright Reed Business Information Ltd.

Related chapters from BN: Chapter 7: Life-Span Development of the Brain and Behavior; Chapter 1: Introduction: Scope and Outlook
Related chapters from MM:Chapter 4: Development of the Brain; Chapter 20:
Link ID: 18242 - Posted: 06.06.2013

People with higher IQs are slow to detect large background movements because their brains filter out non-essential information, say US researchers. Instead, they are good at detecting small moving objects. The findings come in a study of 53 people given a simple, visual test in Current Biology. The results could help scientists understand what makes a brain more efficient and more intelligent. In the study, individuals watched short video clips of black and white bars moving across a computer screen. Some clips were small and filled only the centre of the screen, while others filled the whole screen. The participants' sole task was to identify in which direction the bars were drifting - to the right or to the left. Participants also took a standardised intelligence test. The results showed that people with higher IQ scores were faster at noticing the movement of the bars when observing the smallest image - but they were slower at detecting movement in the larger images. Michael Melnick of the University of Rochester, who was part of the research team said the results were very clear. "From previous research, we expected that all participants would be worse at detecting the movement of large images, but high IQ individuals were much, much worse. The authors explain that in most scenarios, background movement is less important than small moving objects in the foreground, for example driving a car, walking down a hall or moving your eyes across the room. BBC © 2013

Related chapters from BN: Chapter 18: Attention and Higher Cognition; Chapter 1: Introduction: Scope and Outlook
Related chapters from MM:Chapter 14: Attention and Higher Cognition; Chapter 20:
Link ID: 18189 - Posted: 05.25.2013

Jeremy Laurance Iodine deficiency is widespread amongst pregnant women in the UK and may be harming the cognitive development of their children, scientists have found. The first large study of the problem in the UK has revealed that two-thirds of expectant mothers had a mild to moderate deficiency in the mineral, which was associated with significantly lower IQ and reading ability in their children at the ages of eight and nine. Iodine is essential for growth and development of the brain, and pregnant women need 50 per cent more. Researchers said women should ensure they are getting enough from their diet – milk, yogurt and fish are the best sources – and that any pregnancy supplement they take contains iodine. But they warned that kelp and seaweed supplements should be avoided as they contain variable levels of iodine and could lead to overdose. Severe iodine deficiency is known to cause brain damage and is the biggest cause of mental deficiency in the developing world. But mild to moderate iodine deficiency has been little studied – until now. Researchers from the Universities of Surrey and Bristol examined records of 1,000 mothers who were part of the Children of the 90s study which has followed the development of children born to 14,000 mothers in Avon since 1990-91. They found that 67 per cent of the mothers had levels of iodine below that recommended by the World Health Organisation. Their children were divided into groups according to how well they performed on IQ and reading tests at eight and nine. The results showed those whose mothers had low iodine levels were 60 per cent more likely to be in the bottom group. © independent.co.uk

Related chapters from BN: Chapter 7: Life-Span Development of the Brain and Behavior; Chapter 1: Introduction: Scope and Outlook
Related chapters from MM:Chapter 4: Development of the Brain; Chapter 20:
Link ID: 18183 - Posted: 05.22.2013