Chapter 16. None

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Gretchen Cuda Kroen When Kate Klein began working as a nurse in the Cleveland Clinic's Neurointensive Care Unit, one of the first things she noticed was that her patients spent a lot of time in bed. She knew patients with other injuries benefitted from getting up and moving early on, and she wondered why not patients with brain injuries. "I asked myself that question. I asked my colleagues that question," Klein says. "Why aren't these patients getting out of bed? Is there something unique about patients with neurologic injury?" Doctors have long encouraged their surgical patients to get out of bed as soon as it's safe to do so. Movement increases circulation, reduces swelling, inflammation and the risk of blood clots, and it speeds healing. But that wasn't the thinking with brain injuries, explains Edward Manno, director of the Neurointensive Care Unit at the Cleveland Clinic and one of the neurologists who works with Klein. "The predominant thinking was that rest was better suited for the brain," Manno says. Often the damaged brain is susceptible to lack of blood flow. Increased activity may make things worse if initiated too quickly, Manno says. "So many of us thought for quite some time that we needed to put the brain to rest after the initial insult of stroke or other neurologic injury." © 2015 NPR

Keyword: Brain Injury/Concussion
Link ID: 21136 - Posted: 07.06.2015

CONCORD, N.H. — Can an algorithm pass for an author? Can a robot rock the house? A series of contests at Dartmouth College is about to find out. Dartmouth is seeking artificial intelligence algorithms that create "human-quality" short stories, sonnets and dance music sets that will be pitted against human-produced literature, poetry and music selections. The judges won't know which is which. The goal is to determine whether people can distinguish between the two, and whether they might even prefer the computer-generated creativity. "Historically, often when we have advances in artificial intelligence, people will always say, 'Well, a computer couldn't paint a sunset,' or 'a computer couldn't write a beautiful love sonnet,' but could they? That's the question," said Dan Rockmore, director of the Neukom Institute for Computational Science at Dartmouth. Rockmore, a mathematics and computer science professor, spun off the idea for the contests from his experience riding a stationary bike. He started thinking about how the music being played during his spin class helped him pedal at the right the pace, and he was surprised when the instructor told him he selected the songs without the help of computer software. "I left there thinking, 'I wonder if I could write a program that did that, or somebody could?'" he said. "Because that is a creative act — a good spin instructor is a total artist. It sort of opened my mind to thinking about whether a computer or algorithm could produce something that was indistinguishable from or even perhaps preferred over what the human does." The competitions are variations of the "Turing Test," named for British computer scientist Alan Turing, who in 1950 proposed an experiment to determine if a computer could have humanlike intelligence. The classic Turing test involves intelligent computer programs that can fool a person carrying on a conversation with it, and there have been many competitions over the years, said Manuela Veloso, professor of computer science and robotics at Carnegie Mellon University and past president of the Association for the Advancement of Artificial Intelligence. © 2015 The New York Times Company

Keyword: Robotics
Link ID: 21135 - Posted: 07.06.2015

Taunya English What do we know about the power of food to rev up sex drive? Not much. "Really, science has not figured out what determines sexual motivation and sexual attraction. If we knew the answer to that, we'd probably be richer than Pfizer after they invented Viagra," says Dolores Lamb, director of the Center for Reproductive Medicine at Baylor College of Medicine. She hasn't seen any compelling evidence that any particular food can intensify desire. Lamb is a men's health researcher and knows a lot about the intricacies of male plumbing, but she says desire is largely psychological. Even medicines that treat erectile dysfunction can't create enthusiasm. "So the trigger still has to be up in the brain," Lamb says. Still, the idea persists that ginger stirs up lust, or that hot peppers make you hot. "Probably for some folks they do, and it's certainly fun to try," Lamb says. Some legendary aphrodisiacs do have a chemical here or a nutrient there that might support sexual health, but not enough of it to make an immediate difference in the bedroom. Red, juicy watermelon, for example, contains the amino acid citrulline, and that plant nutrient is healthy for erectile tissue in both men and women. But most of the amino acid is found in the rind of the fruit. Consider chili peppers. Capsaicin, which is what provides the heat in a jalapeno, also raises your metabolism and releases feel-good endorphins. "You get kind of a chill down the back of your neck and kind of a tingly, good sensation," Lamb says. "Gets blood flowing better." © 2015 NPR

Keyword: Sexual Behavior
Link ID: 21134 - Posted: 07.06.2015

By Adrian Cho Whether they're from humans, whales, or elephants, the brains of many mammals are covered with elaborate folds. Now, a new study shows that the degree of this folding follows a simple mathematical relationship—called a scaling law—that also explains the crumpling of paper. That observation suggests that the myriad forms of mammalian brains arise not from subtle developmental processes that vary from species to species, but rather from the same simple physical process. In biology, it rare to find a mathematical relationship that so tightly fits all the data, say Georg Striedter, a neuroscientist at the University of California, Irvine. "They've captured something," he says. Still, Striedter argues that the scaling law describes a pattern among fully developed brains and doesn't explain how the folding in a developing brain happens. The folding in the mammalian brain serves to increase the total area of the cortex, the outer layer of gray matter where the neurons reside. Not all mammals have folded cortices. For example, mice and rats have smooth-surfaced brains and are "lissencephalic." In contrast, primates, whales, dogs, and cats have folded brains and are "gyrencephalic." For decades, scientists have struggled to relate the amount of folding in a species' brain to some other characteristic. For example, although animals with tiny brains tend to have smooth ones, there is no clean relationship between the amount of folding—measured by the ratio of the total area of the cortex to the exposed outer surface of the brain—and brain mass. Make a plot of folding versus brain mass for various species and the data points fall all over and not on a unified curve. Similarly, there is no clean relationship between the amount of folding and the number of neurons, the total area of the cortex, or the thickness of the cortex. © 2015 American Association for the Advancement of Science

Keyword: Development of the Brain; Evolution
Link ID: 21133 - Posted: 07.04.2015

By BARRY MEIER and DANIELLE IVORY In a small brick building across the street from a Taco Bell in Marrero, La., patients enter a clear plastic capsule and breathe pure oxygen. The procedure, known as hyperbaric oxygen therapy, uses a pressurized chamber to help scuba divers overcome the bends and to aid people sickened by toxic gases. But Dr. Paul G. Harch, who operates the clinic there on the outskirts of New Orleans, offers it as a concussion treatment. One patient, Rashada Parks, said that she had struggled with neck pain, mood swings and concentration problems ever since she fell and hit her head more than three years ago. Narcotic painkillers hadn’t helped her, nor had antidepressants. But after 40 hourlong treatments, or dives, in a hyperbaric chamber, her symptoms have subsided. “I have hope now,” Ms. Parks said. “It’s amazing.” Three studies run at a taxpayer cost of about $70 million have all come to a far different conclusion. They found that the benefits of hyperbaric oxygen reported by patients like Ms. Parks may have resulted from a placebolike effect, not the therapy’s supposed ability to repair and regenerate brain cells. But undeterred, advocates of the treatment recently persuaded lawmakers to spend even more public money investigating whether the three studies were flawed. A growing industry has developed around concussions, with entrepreneurs, academic institutions and doctors scrambling to find ways to detect, prevent and treat head injuries. An estimated 1.7 million Americans are treated every year after suffering concussions from falls, car accidents, sports injuries and other causes. While the vast majority quickly recover with rest, a small percentage of patients experience lingering effects a year or longer afterward. Along with memory issues, symptoms can include headaches, dizziness and vision and balance problems. © 2015 The New York Times Company

Keyword: Brain Injury/Concussion
Link ID: 21132 - Posted: 07.04.2015

By Kelly Servick How many times would you give your neighbor an electric shock to earn a few extra bucks? Your answer could be more malleable than you think. A new study finds that two common drugs—an antidepressant and a treatment for Parkinson’s disease—can influence moral decisions, a discovery that could help unravel specific mechanisms behind aggression and eventually help researchers design treatments for antisocial behavior. Previous research has linked two neurotransmitters, the brain’s signaling molecules, to our willingness to inflict harm. Serotonin appears to help keep us civil; it’s reduced in the brains of violent offenders, for example. Dopamine, meanwhile, has been shown to prompt aggression in animals, and it’s elevated in a certain part of the brain in people with psychopathic behavior. But measuring how these neurotransmitters contribute to moral decision-making is hard to do in the lab. Many studies rely on theoretical questions like the so-called trolley dilemma, which asks a person whether they would redirect an oncoming train to kill someone if it would save the lives of several others in its path. A person’s answer might not always reflect how they would behave in real life, however. So neuroscientist Molly Crockett of the University of Oxford in the United Kingdom and her colleagues developed a lab test with real consequences. They asked subjects to make a series of decisions about how many moderately painful electric shocks to deliver to themselves or to others. Half the questions gave volunteers a chance to earn money by inflicting self-harm. (For example: “Would you rather endure seven shocks to earn $10 or 10 shocks to earn $15?”) The other half offered the same type of decision, except that someone else stood to be shocked. At the end of the experiment, one of these choices was randomly selected and carried out: The decision-maker got paid, and either they or another person—waiting in a different room—got a series of painful zings on the wrist. Any answer could be the one with real consequences, so “people have to sort of put their money where their mouth is,” Crockett says. © 2015 American Association for the Advancement of Science

Keyword: Emotions
Link ID: 21131 - Posted: 07.04.2015

Spider-like cells inside the brain, spinal cord and eye hunt for invaders, capturing and then devouring them. These cells, called microglia, often play a beneficial role by helping to clear trash and protect the central nervous system against infection. But a new study by researchers at the National Eye Institute (NEI) shows that they also accelerate damage wrought by blinding eye disorders, such as retinitis pigmentosa. NEI is part of the National Institutes of Health. “These findings are important because they suggest that microglia may provide a target for entirely new therapeutic strategies aimed at halting blinding eye diseases of the retina,” said NEI Director, Paul A. Sieving, M.D. “New targets create untapped opportunities for preventing disease-related damage to the eye, and preserving vision for as long as possible.” The findings were published in the journal EMBO Molecular Medicine. Retinitis pigmentosa, an inherited disorder that affects roughly 1 in 4,000 people, damages the retina, the light-sensitive tissue at the back of the eye. Research has shown links between retinitis pigmentosa and several mutations in genes for photoreceptors, the cells in the retina that convert light into electrical signals that are sent to the brain via the optic nerve. In the early stages of the disease, rod photoreceptors, which enable us to see in low light, are lost, causing night blindness. As the disease progresses, cone photoreceptors, which are needed for sharp vision and seeing colors, can also die off, eventually leading to complete blindness.

Keyword: Vision; Glia
Link ID: 21130 - Posted: 07.04.2015

by Sarah Zielinski Seabirds called shearwaters manage to navigate across long stretches of open water to islands where the birds breed. It’s not been clear how the birds do this, but there have been some clues. When scientists magnetically disturbed Cory’s shearwaters, the birds still managed to find their way. But when deprived of their sense of smell, the shearwaters had trouble homing in on their final destination. Smell wouldn’t seem to be all that useful out over the ocean, especially with winds and other atmospheric disturbances playing havoc on any scents wafting through the air. But now researchers say they have more evidence that shearwaters are using olfactory cues to navigate. Andrew Reynolds of Rothamsted Research in Harpenden, England, and colleagues make their case June 30 in the Proceedings of the Royal Society B. Messing with Cory’s shearwaters or other seabirds, like researchers did in earlier studies, wasn’t a good option, the researchers say, because there are conservation concerns when it comes to these species. Instead, they attached tiny GPS loggers to 210 shearwaters belonging to three species: Cory’s shearwaters, Scopoli’s shearwaters and Cape Verde shearwaters. But how would the birds’ path reveal how they were navigating? If they were using olfactory cues, the team reasoned, the birds wouldn’t take a straight path to their target. Instead, they would fly straight for a time, guided in that direction by a particular smell. When they lost that scent, their direction would change, until they picked up another scent that could guide them. And only when a bird got close would it use landmarks, other birds and the odor of the breeding colony as guides. If the birds were using some other method of navigation — or randomly searching for where to go — their paths would look much different. © Society for Science & the Public 2000 - 2015

Keyword: Chemical Senses (Smell & Taste); Animal Migration
Link ID: 21127 - Posted: 07.04.2015

By SINDYA N. BHANOO Learning can be traced back to individual neurons in the brain, according to a new study. “What we wanted to do was see if we could actually create a new association — a memory — and see if we would be able to see actual change in the neurons,” said Matias Ison, a neuroscientist at the University of Leicester in England and one of the study’s authors. He and his colleagues were able to monitor the brain activity of neurosurgical patients at UCLA Medical Center. The patients already had electrodes implanted in their medial temporal lobes for clinical reasons. The patients were first presented with images of notable people — like Jennifer Aniston, Clint Eastwood and Halle Berry. Then, they were shown images of the same people against different backdrops — like the Eiffel Tower, the Leaning Tower of Pisa and the Sydney Opera House. The same neurons that fired for the images of each of the actors also fired when patients were shown the associated landmark images. In other words, the researchers were able to watch as the patients’ neurons recorded a new memory — not just of a particular person, but of the person at a particular place. © 2015 The New York Times Company

Keyword: Learning & Memory
Link ID: 21126 - Posted: 07.02.2015

by Michael Le Page It's good to be mixed-up. People whose parents are distantly related are, on average, taller, smarter and better educated than those whose parents are close relatives. Based on what we know about plants and animals, biologists have long suspected that people of mixed parentage have a genetic advantage. Now an extensive study may have confirmed the hunch. "It does imply that people who come from very different ancestry would be a bit taller and a bit more cognitively able," says team member Jim Wilson of the University of Edinburgh, UK. It has long been known that children are more likely to suffer from genetic diseases if their parents are close relatives, because they may inherit the same harmful gene variants from their mother and father. To probe the wider implications, Wilson and his colleagues analysed genome and life history data from 110 genome studies involving 350,000 people from Africa, Asia, Europe and North America. They were surprised to find no evidence of a link between having closely related parents and most of the traits they looked at, such as cholesterol levels, blood pressure and rates of diabetes. © Copyright Reed Business Information Ltd

Keyword: Sexual Behavior; Genes & Behavior
Link ID: 21120 - Posted: 07.02.2015

by Lisa Grossman Marriage for all, no gay gene required. For same-sex couples in the US, 26 June was a landmark date: the Supreme Court legalised marriage between two men or two women in all 50 states. "[Same-sex couples] ask for equal dignity in the eyes of the law," wrote Associate Justice Anthony Kennedy in the decision. "The Constitution grants them that right." But one thing the decision didn't do was declare sexual orientation a "suspect class" under the law, which would have given it the same protection as race. One of the criteria for this classification is that the trait must be immutable – an argument that the gay rights movement has internalised under the banner of "we're born this way". But although there is some evidence that sexual orientation has a genetic component, most scientists agree that it's not that simple. "There's significant consensus in the scientific community that there's enough different interacting causes for sexual orientation that two different individuals can be gay for different combinations of reasons," says sexuality researcher Lisa Diamond at the University of Utah. "I think all the evidence suggests that we're born with an underlying capacity and then that capacity interacts with a whole bunch of other influences," she says – whether they be prenatal, genetic or environmental. © Copyright Reed Business Information Ltd

Keyword: Sexual Behavior
Link ID: 21117 - Posted: 07.01.2015

Hannah Devlin Science correspondent Two licensed drugs have been shown to halt brain degeneration in mice, raising the prospect of a rapid acceleration in the search for a medicine to beat Alzheimer’s disease. The results, presented on Tuesday at the Alzheimer’s Society annual research conference in Manchester, have been hailed as “hugely promising” because they involve medicines that are already known to be safe and well-tolerated in people – potentially cutting years from the timeline for drugs to reach patients. Speaking ahead of her presentation, Giovanna Mallucci, professor of clinical neuroscience at the University of Cambridge, said: “It’s really exciting. They’re licensed drugs. This means you’d do a straightforward basic clinical trial on a small group of patients because these are not new compounds, they’re known drugs.” The scientists have chosen not to name the two drugs, which are currently used for conditions unrelated to dementia, to avoid the possibility of patients seeking to use them ahead of any clinical trial to prove their efficacy. The findings build on a landmark study two years ago, showing that brain cell death could be halted in mice by switching off a faulty signal in the brain that stops new proteins being produced. However, the breakthrough relied on a compound that had severe physical side-effects including weight loss and diabetes, making it unsuitable for use in humans. The two drugs were identified after Mallucci’s team screened hundreds of licensed compounds in search for something safe that had the same protective effects on the brain. Clare Walton, research manager at the Alzheimer’s Society, said: “The new results are hugely promising because the drugs are already given to people and we know they’re safe.” © 2015 Guardian News and Media Limited

Keyword: Alzheimers
Link ID: 21114 - Posted: 07.01.2015

By Jan Hoffman Guinea pigs do not judge. They do not bully. They are characteristically amiable, social and oh-so-tactile. They tuck comfortably into child-size laps and err on the side of the seriously cute. When playing with guinea pigs at school, children with autism spectrum disorders are more eager to attend, display more interactive social behavior and become less anxious, according to a series of studies, the most recent of which was just published in Developmental Psychobiology. In previous studies, researchers in Australia captured these results by surveying parents and teachers or asking independent observers to analyze videotapes of the children playing. In the new report, however, the researchers analyzed physiological data pointing to the animals’ calming effect on the children. The children played with two guinea pigs in groups of three — one child who was on the spectrum and two typically developing peers. All 99 children in the study, ages 5 to 12, wore wrist bands that monitored their arousal levels, measuring electric charges that race through the skin. Arousal levels can suggest whether a subject is feeling anxious or excited. The first time that typically developing children played with the guinea pigs, they reported feeling happy and registered higher levels of arousal. The researchers speculate that the children were excited by the novelty of the animals. Children with autism spectrum disorders also reported feeling elated, but the wrist band measurements suggested their arousal levels had declined. The animals seem to have lowered the children’s stress, the researchers concluded. © 2015 The New York Times Company

Keyword: Autism
Link ID: 21111 - Posted: 06.30.2015

Henry Nicholls Andy Russell had entered the lecture hall late and stood at the back, listening to the close of a talk by Marta Manser, an evolutionary biologist at the University of Zurich who works on animal communication. Manser was explaining some basic concepts in linguistics to her audience, how humans use meaningless sounds or “phonemes” to generate a vast dictionary of meaningful words. In English, for instance, just 40 different phonemes can be resampled into a rich vocabulary of some 200,000 words. But, explained Manser, this linguistic trick of reorganising the meaningless to create new meaning had not been demonstrated in any non-human animal. This was back in 2012. Russell’s “Holy shit, man” excitement was because he was pretty sure he had evidence for phoneme structuring in the chestnut-crowned babbler, a bird he’s been studying in the semi-arid deserts of south-east Australia for almost a decade. After the talk, Russell (a behavioural ecologist at the University of Exeter) travelled to Zurich to present his evidence to Manser’s colleague Simon Townsend, whose research explores the links between animal communication systems and human language. The fruits of their collaboration are published today in PLoS Biology. One of Russell’s students Jodie Crane had been recording the calls of the chestnut-crowned babbler for her PhD. The PLoS Biology paper focuses on two of these calls, which appear to be made up of two identical elements, just arranged in a different way. © 2015 Guardian News and Media Limited

Keyword: Language; Evolution
Link ID: 21110 - Posted: 06.30.2015

Allison Aubrey Bite into that bread before your main meal, and you'll spike your blood sugar and amp up your appetite. Waiting until the end of your dinner to nosh on bread can blunt those effects. Bite into that bread before your main meal, and you'll spike your blood sugar and amp up your appetite. Waiting until the end of your dinner to nosh on bread can blunt those effects. iStockphoto Ah, the bread basket. You sit down for a nice meal out, and there it appears: piping hot, giving off a waft of yeasty divinity. There's a reason this age-old tradition prevails. Even in the era of paleo and gluten-free, there are still hordes of us who will gladly nosh on crusty, chewy, soul-warming bread. But the downside may be more than just some extra calories. Turns out, eating all those carbs before a meal can amp up our appetites and spike our blood sugar. "The worst situation is having refined carbohydrates on an empty stomach, because there's nothing to slow down the digestion of that carbohydrate into sugar," explains David Ludwig, director of the Optimal Weight for Life Clinic at Boston Children's Hospital. © 2015 NPR

Keyword: Obesity
Link ID: 21108 - Posted: 06.30.2015

By Sunnie Huang, CBC News The story of a Newfoundland man who was struck by a moose but doesn't remember it is not just a curious tale of luck. It also highlights the complex underpinnings of human memory, a neuroscience expert says. Stephen Bromley, from Conche, N.L., struck a moose with his car on Monday, but said he had no recollection it, even days after the collision. It's not the first time that something was amiss about human memory after a moose encounter. hi-moose-car-2012 Michelle Higgins said the roof of her car was peeled back "like a sardine can" after she struck a moose. Another Newfoundlander drove about 40 kilometres with her car's roof peeled back "like a sardine can" after crashing into a moose in 2012. Three years later, she said she still can't recall the incident. The blackout doesn't surprise Scott Watter, a McMaster University professor who specializes in neuroscience, psychology and behaviour. "They are lucky in that sense, but it doesn't seem like a thing that breaks the rules of everything we know about how brains work," he told CBC News. People who sustain head trauma often have poor memory of the event, especially when tested on specific details, Watter said. Also, the more severe the injury gets, the further back the memory loss extends, Watter said. The system at the heart of our memory is a seahorse-shaped section of the brain called the hippocampus, Watter explained. It's responsible for linking different parts of human experience to form a coherent memory. In the most severe — but rare — cases of hippocampus damage, the person can no longer create or retain new memory, as seen in Christopher Nolan's 2000 box office hit Memento. ©2015 CBC/Radio-Canada.

Keyword: Learning & Memory
Link ID: 21106 - Posted: 06.29.2015

Vaughan Bell Marketing has discovered neuroscience and the shiny new product has plenty of style but very little substance. “Neuromarketing” is lighting up the eyes of advertising executives and lightening the wallets of public relations companies. It promises to target the unconscious desires of consumers, which are supposedly revealed by measuring the brain. The more successful agencies have some of the world’s biggest brands on their books and these mega-corporations are happy to trumpet their use of brain science in targeting their key markets. The holy grail of neuromarketing is to predict which ads will lead to most sales before they’ve been released but the reality is a mixture of bad science, bullshit and hope. First, it’s important to realise that the concept of neuroscience is used in different ways in marketing. Sometimes, it’s just an empty ploy aimed at consumers – the equivalent of putting a bikini-clad body next to your product for people who believe they’re above the bikini ploy. A recent Porsche advert apparently showed a neuroscience experiment suggesting that the brain reacts in a similar way to driving their car and flying a fighter jet, but it was all glitter and no gold. The images were computer-generated, the measurements impossible, and the scientist an actor. In complete contrast, neuromarketing is also a serious research area. This is a scientifically sound, genuinely interesting field in cognitive science, where the response to products and consumer decision-making is understood on the level of body and mind. This might involve looking at how familiar brand logos engage the memory systems in the brain, or examining whether the direction of eye gaze of people in ads affects how attention-grabbing they are, or testing whether the brain’s electrical activity varies when watching subtly different ads. Like most of cognitive neuroscience, the studies are abstract, ultra-focused and a long way from everyday experience. © 2015 Guardian News and Media Limited

Keyword: Emotions
Link ID: 21105 - Posted: 06.29.2015

Amy Standen A doctor I interviewed for this story told me something that stuck with me. He said for every person with dementia he treats, he finds himself caring for two patients. That's how hard it can be to be a caregiver for someone with dementia. The doctor is Bruce Miller. He directs the Memory and Aging Center at the University of California, San Francisco. According to Miller, 50 percent of caregivers develop a major depressive illness because of the caregiving. "The caregiver is so overburdened that they don't know what to do next," he says. "This adds a huge burden to the medical system." This burden is going increase dramatically in the coming decade. By 2025, 7 million Americans will have Alzheimer's disease, according to one recent estimate. Millions more will suffer from other types of dementia. Together these diseases may become the most expensive segment of the so-called "silver tsunami" — 80 million baby boomers who are getting older and needing more medical care. The cost of caring for Alzheimer's patients alone is expected to triple by 2050, to more than $1 trillion a year. So UCSF, along with the University of Nebraska Medical Center, is beginning a $10 million study funded by the federal Centers for Medicare & Medicaid Innovation. Researchers plan to develop a dementia "ecosystem," which aims to reduce the cost of caring for the growing number of dementia patients and to ease the strain on caregivers. © 2015 NPR

Keyword: Alzheimers
Link ID: 21104 - Posted: 06.29.2015

by Clare Wilson Do you dream of where you'd like to go tomorrow? It looks like rats do. When the animals are shown a food treat at the end of a path they cannot access and then take a nap, the neurons representing that route in their brains fire as they sleep – as if they are dreaming about running down the corridor to grab the grub. "It's like looking at a holiday brochure for Greece the day before you go – that night you might dream about the pictures," says Hugo Spiers of University College London. Like people, rats store mental maps of the world in their hippocampi, two curved structures on either side of the brain. Putting electrodes into rats' brains as they explore their environment has shown that different places are recorded and remembered by different combinations of hippocampal neurons firing together. These "place cells" fire not only when a rat is in a certain location, but also when it sleeps, as if it is dreaming about where it has been in the past. Spiers's team wondered whether this activity during sleep might also reflect where a rat wants to go in future. They placed four rats at the bottom of a T-shaped pathway, with entry to the top bar of the T blocked by a grille. Food was placed at the end of one arm, in a position visible to the animals. Next they encouraged the rats to sleep in a cosy nest and recorded their hippocampus activity with about 50 electrodes each as they rested. Finally they put the rats back into the maze, but now with the grille and the treat removed. © Copyright Reed Business Information Ltd.

Keyword: Sleep
Link ID: 21103 - Posted: 06.27.2015

Sharon Darwish Bottlenose dolphins have an average brain mass of 1.6 kg, slightly greater than that of humans, and about four times the size of chimpanzee brains. Although you couldn’t really imagine a dolphin writing poetry, dolphins demonstrate high levels of intelligence and social behaviour. For example, they display mirror self-recognition, as well as an understanding of symbol-based communication systems. Research into the differing brain sizes and intellectual capabilities within the animal kingdom is fascinating. Why have some species evolved to be more intelligent than others? Does brain size affect cognitive ability? Some studies say yes, but some insist otherwise. It really depends which species we are talking about. In humans, for example, larger brains do not indicate higher intelligence – otherwise Einstein, who had an average-sized brain, may have not been quite as successful in his career. (Yes, that link was to a 23-pager on the analysis of Einstein’s brain. It makes for great bedtime reading.) Most neuroscientists now believe that it is the structure of the brain on a cellular and molecular level that determines its computational capacity. Within certain animal species however, a larger brain offers evolutionary advantage. For example, large-brained female guppies are better survivors and demonstrate greater cognitive strengths than their smaller-brained counterparts. © 2015 Guardian News and Media Limited

Keyword: Development of the Brain; Genes & Behavior
Link ID: 21102 - Posted: 06.27.2015