Carl Zimmer In recent years, a peculiar sort of public performance has taken place periodically on the sidewalks of Seattle. It begins with a woman named Kaeli N. Swift sprinkling peanuts and cheese puffs on the ground. Crows swoop in to feed on the snacks. While Ms. Swift observes the birds from a distance, notebook in hand, another person walks up to the birds, wearing a latex mask and a sign that reads “UW CROW STUDY.” In the accomplice’s hands is a taxidermied crow, presented like a tray of hors d’oeuvres. This performance is not surreal street theater, but an experiment designed to explore a deep biological question: What do crows understand about death? Ms. Swift has been running this experiment as part of her doctoral research at the University of Washington, under the guidance of John M. Marzluff, a biologist. Dr. Marzluff and other experts on crow behavior have long been intrigued by the way the birds seem to congregate noisily around dead comrades. Dr. Marzluff has witnessed these gatherings many times himself, and has heard similar stories from other people. “Whenever I give a talk about crows, there’s always someone who says, ‘Well, what about this?’ ” he said. Dr. Marzluff and Ms. Swift decided to bring some scientific rigor to these stories. They wanted to determine whether a dead crow really does trigger a distinctive response from living crows and, if so, what the purpose of the large, noisy gatherings might be. To run the experiment, Ms. Swift began by delivering food to a particular spot each day, so that the crows learned to congregate there to eat. Then one of her volunteers would approach the feast with a dead crow, and Ms. Swift observed how the birds reacted. © 2015 The New York Times Company

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: 21473 - Posted: 10.03.2015

By Michael Balter Are some animals smarter than others? It’s hard to say, because you can’t sit a chimpanzee or a mouse down at a table for an IQ test. But a new study, in which scientists tested wild robins on a variety of skills, concludes that they do differ in the kind of “general intelligence” that IQ tests are supposed to measure. General intelligence is usually defined as the ability to do well on multiple cognitive tasks, from math skills to problem solving. For years, researchers have questioned whether measurable differences exist in humans and nonhumans alike. In humans, factors like education and socioeconomic status can affect performance. When it comes to animals, the problem is compounded for two main reasons: First, it is very difficult to design and administer tests that pick up on overall smarts instead of specific skills, such as the keen memories of food-hoarding birds or the fine motor skills of chimpanzees that make tools for finding insects in trees. Second, differences in animal test scores can depend on how motivated they are to perform. Because most experiments award would-be test-takers with food, an empty (or a full) stomach might be all it takes to skew the results. Thus, even studies that suggest variations in intelligence among mice, birds, and apes all carry the caveat that alternative explanations could be at play. To get around some of these limitations, a team led by Rachael Shaw, an animal behavior researcher at Victoria University of Wellington, turned to a population of New Zealand North Island robins for a new round of experiments. The robins live at the Zealandia wildlife sanctuary, a 225-hectare nature paradise in Wellington where more than 700 of the birds live wild and protected from predators in the middle of the city. © 2015 American Association for the Advancement of Science.

Related chapters from BN: Chapter 6: Evolution of the Brain and Behavior; Chapter 17: Learning and Memory
Related chapters from MM:Chapter 13: Memory and Learning
Link ID: 21424 - Posted: 09.20.2015

By Steve Mirsky It's nice to know that the great man we celebrate in this special issue had a warm sense of humor. For example, in 1943 Albert Einstein received a letter from a junior high school student who mentioned that her math class was challenging. He wrote back, “Do not worry about your difficulties in mathematics; I can assure you that mine are still greater.” Today we know that his sentiment could also have been directed at crows, which are better at math than those members of various congressional committees that deal with science who refuse to acknowledge that global temperatures keep getting higher. Studies show that crows can easily discriminate between a group of, say, three objects and another containing nine. They have more trouble telling apart groups that are almost the same size, but unlike the aforementioned committee members, at least they're trying. A study in the Proceedings of the National Academy of Sciences USA finds that the brain of a crow has nerve cells that specialize in determining numbers—a method quite similar to what goes on in our primate brain. Human and crow brains are substantially different in size and organization, but convergent evolution seems to have decided that this kind of neuron-controlled numeracy is a good system. (Crows are probably unaware of evolution, which is excusable. Some members of various congressional committees that deal with science pad their reactionary résumés by not accepting evolution, which is astonishing.) © 2015 Scientific American

Related chapters from BN: Chapter 18: Attention and Higher Cognition; Chapter 6: Evolution of the Brain and Behavior
Related chapters from MM:Chapter 14: Attention and Higher Cognition
Link ID: 21390 - Posted: 09.09.2015

Alison Abbott The octopus genome offers clues to how cephalopods evolved intelligence to rival the craftiest vertebrates. With its eight prehensile arms lined with suckers, camera-like eyes, elaborate repertoire of camouflage tricks and spooky intelligence, the octopus is like no other creature on Earth. Added to those distinctions is an unusually large genome, described in Nature1 on 12 August, that helps to explain how a mere mollusc evolved into an otherworldly being. “It’s the first sequenced genome from something like an alien,” jokes neurobiologist Clifton Ragsdale of the University of Chicago in Illinois, who co-led the genetic analysis of the California two-spot octopus (Octopus bimaculoides). The work was carried out by researchers from the University of Chicago, the University of California, Berkeley, the University of Heidelberg in Germany and the Okinawa Institute of Science and Technology in Japan. The scientists also investigated gene expression in twelve different types of octopus tissue. “It’s important for us to know the genome, because it gives us insights into how the sophisticated cognitive skills of octopuses evolved,” says neurobiologist Benny Hochner at the Hebrew University of Jerusalem in Israel, who has studied octopus neurophysiology for 20 years. Researchers want to understand how the cephalopods, a class of free-floating molluscs, produced a creature that is clever enough to navigate highly complex mazes and open jars filled with tasty crabs. © 2015 Nature Publishing Group

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: 21295 - Posted: 08.13.2015

Alexandra Sims Intelligent people are not only smarter than the average person - it seems they could also live longer as well. A study by the London School of Economics found that smarter siblings are more likely to outlive their less clever brothers and sisters, with genetics accounting for 95 per cent of the connection between intelligence and life span. The scientists examined the differences in longevity between identical twins, who share all of their genes and non-identical twins, who on average share half of their genes. Writing in the International Journal of Epidemiology, scientists noted the difference in intellect between the twins and the age at which they died. Focusing on three different twin studies from Sweden, Denmark and the United States the researchers examined sets of twins for whom both intelligence and age of death had been recorded in pairs where at least one of the twins had died. In both types of twins it was found that the smarter of the two lived longer, but this effect was far more prominent in non-identical twins. Rosalind Arden, a research associate at the LSE, told The Times that "the association between top jobs and longer lifespans is more a result of genes than having a big desk.” She added though that the research does not mean parents can "deduce your child’s likely lifespan from how he or she does in their exams this summer”.

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: 21222 - Posted: 07.28.2015

By Kiona Smith-Strickland Are crows the smartest animals of all? Many scientists think that corvids — the family of birds that includes crows, ravens, rooks and jays — may be among the most intelligent animals on Earth, based on their ability to solve problems, make tools and apparently consider both possible future events and other individuals’ states of mind. “There’s a lot of research that has been done with both ravens and crows because they are such intelligent species,” said Margaret Innes, an assistant curator at the Maryland Zoo in Baltimore. Even in humans, defining and measuring intelligence is difficult, and it’s more complicated in other species, which have very different body shapes and have evolved for their niche in the environment. However, scientists who study cognition have defined a few measures of intelligence: recognizing oneself in a mirror, solving complex problems, making tools, using analogies and symbols, and reasoning about what others are thinking. For a long time, biologists expected most of these mental feats to be unique to primates. The great apes — chimpanzees, orangutans and gorillas — succeed at nearly all of these tasks, from making and using tools to learning large vocabularies of symbols, as well as recognizing themselves in mirrors. A select few other mammals also meet most of the accepted criteria for intelligence. Dogs and dolphins, for instance, are very good at tasks involving social intelligence, such as communication, conflict resolution and reasoning about what others are thinking. Dolphins are also capable of basic tool use — for instance, carrying sea sponges in their mouths to shield their noses from scrapes and bumps as they forage on the ocean floor.

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: 21086 - Posted: 06.23.2015

Alison Abbott Redouan Bshary well remembers the moment he realized that fish were smarter than they are given credit for. It was 1998, and Bshary was a young behavioural ecologist with a dream project: snorkelling in Egypt's Red Sea to observe the behaviour of coral-reef fish. That day, he was watching a grumpy-looking grouper fish as it approached a giant moray eel. As two of the region's top predators, groupers and morays might be expected to compete for their food and even avoid each other — but Bshary saw them team up to hunt. First, the grouper signalled to the eel with its head, and then the two swam side by side, with the eel dipping into crevices, flushing out fish beyond the grouper's reach and getting a chance to feed alongside. Bshary was astonished by the unexpected cooperation; if he hadn't had a snorkel in his mouth, he would have gasped. This underwater observation was the first in a series of surprising discoveries that Bshary has gone on to make about the social behaviour of fish. Not only can they signal to each other and cooperate across species, but they can also cheat, deceive, console or punish one another — even show concern about their personal reputations. “I have always had a lot of respect for fish,” says Bshary. “But one after the other, these behaviours took me by surprise.” His investigations have led him to take a crash course in scuba diving, go beach camping in Egypt and build fake coral reefs in Australia. The work has also destroyed the stereotypical idea that fish are dumb creatures, capable of only the simplest behaviours — and it has presented a challenge to behavioural ecologists in a different field. Scientists who study primates have claimed that human-like behaviours such as cooperation are the sole privilege of animals such as monkeys and apes, and that they helped to drive the evolution of primates' large brains. Bshary — quiet, but afraid of neither adventure nor of contesting others' ideas — has given those scientists reason to think again. © 2015 Nature Publishing Grou

Related chapters from BN: Chapter 6: Evolution of the Brain and Behavior; Chapter 18: Attention and Higher Cognition
Related chapters from MM:Chapter 14: Attention and Higher Cognition
Link ID: 20983 - Posted: 05.26.2015

by Karl Gruber "As clever as a guppy" is not a huge compliment. But intelligence does matter to these tropical fish: big-brained guppies are more likely to outwit predators and live longer than their dim-witted peers. Alexander Kotrschal at Stockholm University, Sweden, and his colleagues bred guppies (Poecilia reticulata) to have brains that were bigger or smaller than average. His team previously showed that bigger brains meant smarter fish. When put in an experimental stream with predators, big-brained females were eaten about 13 per cent less often than small-brained ones. There was no such link in males, and the researchers suspect that their bright colours may counter any benefits of higher intelligence. They did find, Kotrschal says , that large-brained males were faster swimmers and better at learning and remembering the location of a female. "This is exciting because it confirms a critical mechanism for brain size evolution," says Kotrschal. It shows, he adds, that interactions between predator and prey can affect brain size. It might seem obvious that bigger brains would help survival. Yet previous research simply found a correlation between the two, leaving the possibility open that some third factor may have been driving the effect. Now, direct brain size manipulation allowed Kotrschal's team to pin it down as a cause of better survival. "This is the first time anyone has tested whether a larger brain confers a survival benefit," says Kotrschal. "The fact that large-brained females survived better in a naturalistic setting is the first experimental proof that a larger brain is beneficial for the fitness of its bearer. This is like watching evolution happen and shows how brain size evolves." © Copyright Reed Business Information Ltd.

Related chapters from BN: Chapter 6: Evolution of the Brain and Behavior; Chapter 12: Sex: Evolutionary, Hormonal, and Neural Bases
Related chapters from MM:Chapter 8: Hormones and Sex
Link ID: 20962 - Posted: 05.21.2015

by Ashley Yeager New Caledonian crows are protective of their tools. The birds safeguard the sticks they use to find food and become even more careful with the tools as the cost of losing them goes up. Researchers videotaped captive and wild Corvus moneduloides crows and tracked what the birds did with their sticks. In between eating, the birds tucked the tools under their toes or left them in the holes they were probing. When higher up in the trees, the birds dropped the tools less often and were more likely to leave them in the holes they were probing than when they were on the ground. The finding, published May 20 in the Proceedings of the Royal Society B, shows how tool-protection tactics can prevent costly losses that could keep the crows from chowing down. © Society for Science & the Public 2000 - 2015

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: 20953 - Posted: 05.20.2015

By BENEDICT CAREY Behind all those canned compliments for older adults — spry! wily! wise! — is an appreciation for something that scientists have had a hard time characterizing: mental faculties that improve with age. Knowledge is a large part of the equation, of course. People who are middle-aged and older tend to know more than young adults, by virtue of having been around longer, and score higher on vocabulary tests, crossword puzzles and other measures of so-called crystallized intelligence. Still, young adults who consult their elders (mostly when desperate) don’t do so just to gather facts, solve crosswords or borrow a credit card. Nor, generally, are they looking for help with short-term memory or puzzle solving. Those abilities, called fluid intelligence, peak in the 20s. No, the older brain offers something more, according to a new paper in the journal Psychological Science. Elements of social judgment and short-term memory, important pieces of the cognitive puzzle, may peak later in life than previously thought. The postdoctoral fellows Joshua Hartshorne of M.I.T. and Laura Germine of Harvard and Massachusetts General Hospital analyzed a huge trove of scores on cognitive tests taken by people of all ages. The researchers found that the broad split in age-related cognition — fluid in the young, crystallized in the old — masked several important nuances. “This dichotomy between early peaks and later peaks is way too coarse,” Dr. Hartshorne said. “There are a lot more patterns going on, and we need to take those into account to fully understand the effects of age on cognition.” The new paper is hardly the first challenge to the scientific literature on age-related decline, and it won’t be the last. A year ago, German scientists argued that cognitive “deficits” in aging were caused largely by the accumulation of knowledge — that is, the brain slows down because it has to search a larger mental library of facts. That idea has stirred some debate among scientists. Experts said the new analysis raised a different question: Are there distinct, independent elements of memory and cognition that peak at varying times of life? © 2015 The New York Times Company

Related chapters from BN: Chapter 17: Learning and Memory; Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 4: Development of the Brain; Chapter 4: Development of the Brain
Link ID: 20693 - Posted: 03.17.2015

By Gail Sullivan Chemicals found in food and common household products have been linked to lower IQ in kids exposed to high levels during pregnancy. Previous research linked higher exposure to chemicals called "phthalates" to poor mental and motor development in preschoolers. This study was said to be the first to report a link between prenatal exposure to the chemicals and childhood development. Researchers from Columbia University’s Mailman School of Public Health studied exposure to five types of phthalates, which are sometimes referred to as “hormone disruptors” or “endocrine disruptors.” Among these, di-n-butyl phthalate (DnBP) is used in shower curtains, raincoats, hairspray, food wraps, vinyl and pill coating, among other things — but according to the EPA, the largest source of exposure may be seafood. Di-isobutyl phthalate (DiBP) and Butylbenzyl phthalate (BBzP) are added to plastics to make them flexible. These chemicals may also used in makeup, nail polish, lacquer and explosives. The researchers linked prenatal exposure to phthalates to a more than six-point drop in IQ score compared with kids with less exposure. The study, “Persistent Associations between Maternal Prenatal Exposure to Phthalates on Child IQ at Age 7 Years," was published Wednesday in the journal PLOS One. "The magnitude of these IQ differences is troubling," one of the study’s authors, Robin Whyatt, said in a press release. "A six- or seven-point decline in IQ may have substantial consequences for academic achievement and occupational potential."

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: 20413 - Posted: 12.13.2014

James Gorman Evidence has been mounting for a while that birds and other animals can count, particularly when the things being counted are items of food. But most of the research is done under controlled conditions. In a recent experiment with New Zealand robins, Alexis Garland and Jason Low at Victoria University of Wellington tested the birds in a natural setting, giving them no training and no rewards, and showed that they knew perfectly well when a scientist had showed them two mealworms in a box, but then delivered only one. The researchers reported the work this fall in the journal Behavioural Processes. The experiment is intriguing to watch, partly because it looks like a child’s magic trick. The apparatus used is a wooden box that has a sliding drawer. After clearly showing a robin that she was dropping two mealworms in a circular well in the box, Dr. Garland would slide in the drawer. It covered the two worms with an identical-looking circular well containing only one worm. When the researcher moved away and the robin flew down and lifted off a cover, it would find only one worm. The robins pecked intensely at the box, behavior they didn’t show if they found the two worms they were expecting. Earlier experiments had also shown the birds to be good at counting, and Dr. Garland said that one reason might be that they are inveterate thieves. Mates, in particular, steal from one another’s food caches, where they hide perishable prey like worms or insects. “If you’ve got a mate that steals 50 or more percent of your food,” she said, you’d better learn how to keep track of how many mealworms you’ve got. © 2014 The New York Times Company

Related chapters from BN: Chapter 6: Evolution of the Brain and Behavior; Chapter 18: Attention and Higher Cognition
Related chapters from MM:Chapter 14: Attention and Higher Cognition
Link ID: 20324 - Posted: 11.18.2014

By Sarah Zielinski The marshmallow test is pretty simple: Give a child a treat, such as a marshmallow, and promise that if he doesn’t eat it right away, he’ll soon be rewarded with a second one. The experiment was devised by Stanford psychologist Walter Mischel in the late 1960s as a measure of self-control. When he later checked back in with kids he had tested as preschoolers, those who had been able to wait for the second treat appeared to be doing better in life. They tended to have fewer behavioral or drug-abuse problems, for example, than those who had given in to temptation. Most attempts to perform this experiment on animals haven’t worked out so well. Many animals haven’t been willing to wait at all. Dogs, primates, and some birds have done a bit better, managing to wait at least a couple of minutes before eating the first treat. The best any animal has managed has been 10 minutes—a record set earlier this year by a couple of crows. The African grey parrot is a species known for its intelligence. Animal psychologist Irene Pepperberg, now at Harvard, spent 30 years studying one of these parrots, Alex, and showed that the bird had an extraordinary vocabulary and capacity for learning. Alex even learned to add numerals before his death in 2007. Could an African grey pass the marshmallow test? Adrienne E. Koepke of Hunter College and Suzanne L. Gray of Harvard University tried the experiment on Pepperberg’s current star African grey, a 19-year-old named Griffin. In their test, a researcher took two treats, one of which Griffin liked slightly better, and put them into cups. Then she placed the cup with the less preferred food in front of Griffin and told him, “wait.” She took the other cup and either stood a few feet away or left the room. After a random amount of time, from 10 seconds to 15 minutes, she would return. If the food was still in the cup, Griffin got the nut he was waiting for. Koepke and colleagues presented their findings last month at the Animal Behavior Society meeting at Princeton. © 2014 The Slate Group LLC.

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: 20061 - Posted: 09.11.2014

Ewen Callaway Researchers found 69 genes that correlate with higher educational attainment — and three of those also also appear to have a direct link to slightly better cognitive abilities. Scientists looking for the genes underlying intelligence are in for a slog. One of the largest, most rigorous genetic study of human cognition1 has turned up inconclusive findings, and experts concede that they will probably need to scour the genomes of more than 1 million people to confidently identify even a small genetic influence on intelligence and other behavioural traits. Studies of twins have repeatedly confirmed a genetic basis for intelligence, personality and other aspects of behaviour. But efforts to link IQ to specific variations in DNA have led to a slew of irreproducible results. Critics have alleged that some of these studies' methods were marred by wishful thinking and shoddy statistics. A sobering editorial in the January 2012 issue of Behavior Genetics2 declared that “it now seems likely that many of the published findings of the last decade are wrong or misleading and have not contributed to real advances in knowledge”. In 2011, an international collaboration of researchers launched an effort to bring more rigour to studies of how genes contribute to behaviour. The group, called the Social Sciences Genetic Association Consortium, aimed to do studies using practices borrowed from the medical genetics community, which emphasizes large numbers of participants, rigorous statistics and reproducibility. In a 2013 study3 comparing the genomes of more than 126,000 people, the group identified three gene variants associated with with how many years of schooling a person had gone through or whether they had attended university. But the effect of these variants was small — each variant correlated with roughly one additional month of schooling in people who had it compared with people who did not. © 2014 Nature Publishing Group

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: 20050 - Posted: 09.09.2014

|By Madhuvanthi Kannan We humans assume we are the smartest of all creations. In a world with over 8.7 million species, only we have the ability to understand the inner workings of our body while also unraveling the mysteries of the universe. We are the geniuses, the philosophers, the artists, the poets and savants. We amuse at a dog playing ball, a dolphin jumping rings, or a monkey imitating man because we think of these as remarkable acts for animals that, we presume, aren’t smart as us. But what is smart? Is it just about having ideas, or being good at language and math? Scientists have shown, time and again, that many animals have an extraordinary intellect. Unlike an average human brain that can barely recall a vivid scene from the last hour, chimps have a photographic memory and can memorize patterns they see in the blink of an eye. Sea lions and elephants can remember faces from decades ago. Animals also have a unique sense perception. Sniffer dogs can detect the first signs of colon cancer by the scents of patients, while doctors flounder in early diagnosis. So the point is animals are smart too. But that’s not the upsetting realization. What happens when, for just once, a chimp or a dog challenges man to one of their feats? Well, for one, a precarious face-off – like the one Matt Reeves conceived in the Planet of the Apes – would seem a tad less unlikely than we thought. In a recent study by psychologists Colin Camerer and Tetsuro Matsuzawa, chimps and humans played a strategy game – and unexpectedly, the chimps outplayed the humans. Chimps are a scientist’s favorite model to understand human brain and behavior. Chimp and human DNAs overlap by a whopping 99 percent, which makes us closer to chimps than horses to zebras. Yet at some point, we evolved differently. Our behavior and personalities, molded to some extent by our distinct societies, are strikingly different from that of our fellow primates. Chimps are aggressive and status-hungry within their hierarchical societies, knit around a dominant alpha male. We are, perhaps, a little less so. So the question arises whether competitive behavior is hard-wired in them. © 2014 Scientific American

Related chapters from BN: Chapter 6: Evolution of the Brain and Behavior; Chapter 15: Emotions, Aggression, and Stress
Related chapters from MM:Chapter 11: Emotions, Aggression, and Stress
Link ID: 20028 - Posted: 09.03.2014

By Emily Underwood Old age may make us wiser, but it rarely makes us quicker. In addition to slowing down physically, most people lose points on intelligence tests as they enter their golden years. Now, new research suggests the loss of certain types of cognitive skills with age may stem from problems with basic sensory tasks, such as making quick judgments based on visual information. Although there’s no clear causal link between the two types of thinking yet, the new work could provide a simple, affordable way to track mental decline in senior citizens, scientists say. Since the 1970s, researchers who study intelligence have hypothesized that smartness, as measured on standard IQ tests, may hinge on the ability to quickly and efficiently sample sensory information from the environment, says Stuart Ritchie, a psychologist at the University of Edinburgh in the United Kingdom. Today it’s well known that people who score high on such tests do, indeed, tend to process such information more quickly than those who do poorly, but it’s not clear how these measures change with age, Ritchie says. Studying older people over time can be challenging given their uncertain health, but Ritchie and his colleagues had an unusual resource in the Lothian Birth Cohort, a group of people born in 1936 whose mental function has been periodically tested by the Scottish government since 1947—their first IQ test was at age 11. After recruiting more than 600 cohort members for their study, Ritchie and colleagues tracked their scores on a simple visual task three times over 10 years, repeating the test at the mean ages of 70, 73, and 76. © 2014 American Association for the Advancement of Science

Related chapters from BN: Chapter 10: Vision: From Eye to Brain; Chapter 7: Life-Span Development of the Brain and Behavior
Related chapters from MM:Chapter 7: Vision: From Eye to Brain; Chapter 4: Development of the Brain
Link ID: 19917 - Posted: 08.05.2014

Posted by Katie Langin In a battle of wits, could a bird outsmart a kindergartner? Don’t be too quick to say no: One clever young bird solved a problem that has stumped 5-year-old children, according to a new study. The bird—a New Caledonian crow named Kitty—figured out that dropping rocks in one water-filled tube was the key to raising the water level in another, seemingly unconnected tube, giving her access to a floating morsel of meat. To solve this problem, Kitty needed to decipher a confusing cause-and-effect relationship, basically akin to figuring out that if you flip a switch on the wall, a ceiling light will turn on. This mental ability was once thought to be restricted to humans, but causal reasoning—the ability to understand cause and effect—has now been identified in a handful of animals, from chimpanzees to rats. Crows are the Einsteins of the bird world, renowned for their ability to make tools and solve complex puzzles. (Watch a video of a New Caledonian crow solving problems.) Their impressive mental capacity was even apparent to the ancient Greeks. In one of Aesop’s fables, a thirsty crow is presented with a dilemma when he cannot reach the water at the bottom of a pitcher. He figures out that the water level rises when he drops pebbles into the pitcher, and many pebbles later he is rewarded with a drink. As it turns out, there’s some truth to this fictional story. A study published earlier this year reported that New Caledonian crows will place rocks in water-filled tubes if they can’t reach a piece of meat that is attached to a floating cork. © 1996-2013 National Geographic Society.

Related chapters from BN: Chapter 18: Attention and Higher Cognition
Related chapters from MM:Chapter 14: Attention and Higher Cognition
Link ID: 19878 - Posted: 07.26.2014

Sara Reardon For chimps, nature and nurture appear to contribute equally to intelligence. Smart chimpanzees often have smart offspring, researchers suggest in one of the first analyses of the genetic contribution to intelligence in apes. The findings, published online today in Current Biology1, could shed light on how human intelligence evolved, and might even lead to discoveries of genes associated with mental capacity. A team led by William Hopkins, a psychologist at Georgia State University in Atlanta, tested the intelligence of 99 chimpanzees aged 9 to 54 years old, most of them descended from the same group of animals housed at the Yerkes National Primate Research Center in Atlanta. The chimps faced cognitive challenges such as remembering where food was hidden in a rotating object, following a human’s gaze and using tools to solve problems. A subsequent statistical analysis revealed a correlation between the animals' performance on these tests and their relatedness to other chimpanzees participating in the study. About half of the difference in performance between individual apes was genetic, the researchers found. In humans, about 30% of intelligence in children can be explained by genetics; for adults, who are less vulnerable to environmental influences, that figure rises to 70%. Those numbers are comparable to the new estimate of the heritability of intelligence across a wide age range of chimps, says Danielle Posthuma, a behavioural geneticist at VU University in Amsterdam, who was not involved in the research. “This study is much overdue,” says Rasmus Nielsen, a computational biologist at the University of California, Berkeley. “There has been enormous focus on understanding heritability of intelligence in humans, but very little on our closest relatives.” © 2014 Nature Publishing Group

Related chapters from BN: Chapter 18: Attention and Higher Cognition; Chapter 6: Evolution of the Brain and Behavior
Related chapters from MM:Chapter 14: Attention and Higher Cognition
Link ID: 19820 - Posted: 07.12.2014

By Neuroskeptic Nothing that modern neuroscience can detect, anyway. This is the message of a provocative article by Pace University psychologist Terence Hines, just published in Brain and Cognition: Neuromythology of Einstein’s brain As Hines notes, the story of how Einstein’s brain was preserved is well known. When the physicist died in 1955, his wish was to be cremated, but the pathologist who performed the autopsy decided to save his brain for science. Einstein’s son Hans later gave his blessing to this fait accompli. Samples and photos of the brain were then made available to neuroscientists around the world, who hoped to discover the secret of the great man’s genius. Many have claimed to have found it. But Hines isn’t convinced. Some researchers, for instance, have used microscopy to examine Einstein’s brain tissue on a histological (cellular) level. Most famous amongst these studies is Diamond et al, who in 1985 reported that Einstein’s brain had a significantly higher proportion of glial cells than those of matched, normal control brains. However, Hines points out that this ‘finding’ may have been a textbook example of the multiple-comparisons problem: Diamond et al. (1985) reported four different t-tests, each comparing Einstein’s brain to the brains of the controls. Only one of the four tests performed was significant at the .05 level. Although only the results of the neuron to glial cell ratios were reported by Diamond et al. (1985), the paper makes it clear that at least six other dependent measures were examined: (1) number of neurons, (2) total number of glial cells, (3) number of astrocytes, (4) number of oligodendrocytes, (5) neuron to astrocyte ratio and (6) neuron to oligodendrocyte ratio. Thus a total of seven different dependent measures were examined in four different brain areas for a total of 28 comparisons… one p less than 0.05 result out of 28 is not surprising. Other histological studies followed from other researchers, but Hines says that they do not present a coherent picture of clear differences:

Related chapters from BN: Chapter 7: Life-Span Development of the Brain and Behavior; Chapter 2: Functional Neuroanatomy: The Cells and Structure of the Nervous System
Related chapters from MM:Chapter 4: Development of the Brain; Chapter 1: Cells and Structures: The Anatomy of the Nervous System
Link ID: 19654 - Posted: 05.26.2014

|By Andrea Anderson Our knack for language helps us structure our thinking. Yet the ability to wax poetic about trinkets, tools or traits may not be necessary to think about them abstractly, as was once suspected. A growing body of evidence suggests nonhuman animals can group living and inanimate things based on less than obvious shared traits, raising questions about how creatures accomplish this task. In a study published last fall in the journal PeerJ, for example, Oakland University psychology researcher Jennifer Vonk investigated how well four orangutans and a western lowland gorilla from the Toronto Zoo could pair photographs of animals from the same biological groups. Vonk presented the apes with a touch-screen computer and got them to tap an image of an animal—for instance, a snake—on the screen. Then she showed each ape two side-by-side animal pictures: one from the same category as the animal in the original image and one from another—for example, images of a different reptile and a bird. When they correctly matched animal pairs, they received a treat such as nuts or dried fruit. When they got it wrong, they saw a black screen before beginning the next trial. After hundreds of such trials, Vonk found that all five apes could categorize other animals better than expected by chance (although some individuals were better at it than others). The researchers were impressed that the apes could learn to classify mammals of vastly different visual characteristics together—such as turtles and snakes—suggesting the apes had developed concepts for reptiles and other categories of animals based on something other than shared physical traits. Dogs, too, seem to have better than expected abstract-thinking abilities. They can reliably recognize pictures of other dogs, regardless of breed, as a study in the July 2013 Animal Cognition showed. The results surprised scientists not only because dog breeds vary so widely in appearance but also because it had been unclear whether dogs could routinely identify fellow canines without the advantage of smell and other senses. Other studies have found feats of categorization by chimpanzees, bears and pigeons, adding up to a spate of recent research that suggests the ability to sort things abstractly is far more widespread than previously thought. © 2014 Scientific American

Related chapters from BN: Chapter 6: Evolution of the Brain and Behavior; Chapter 18: Attention and Higher Cognition
Related chapters from MM:Chapter 14: Attention and Higher Cognition
Link ID: 19614 - Posted: 05.15.2014