Links for Keyword: Miscellaneous

Follow us on Facebook and Twitter, or subscribe to our mailing list, to receive news updates. Learn more.

Links 81 - 100 of 526

By Laura Sanders Satirist Stephen Colbert envisions his “Colbert Nation” mentally marching in lockstep with his special brand of patriotism. But scientists have done him one better, by creating tiny worm-bots completely under their control. Rather than comedic persuasion, these scientists are using a dot of laser light. With it they can make a worm turn left, freeze or lay an egg. The researchers report their work online January 16 in Nature Methods. The new system, named CoLBeRT for “Controlling Locomotion and Behavior in Real Time,” doesn’t just create a mindless zombie-worm, though. It gives scientists the ability to pick apart complicated behaviors on a cell-by-cell basis. “This system is really remarkable,” says biological physicist William Ryu of the University of Toronto, who was not involved in the research. “It’s a very important advance in pursuit of the goal of understanding behavior.” Transparent and small, the nematode C. elegans is particularly amenable to light-based mind control. Another benefit of the worm is that researchers know the precise location of all 302 of its nerve cells. But until now, there wasn’t a good way to study each cell by itself, especially in a wriggling animal. “This tool allows us to go in and poke and prod at those neurons in an animal as it’s moving, and see exactly what each neuron does,” says study coauthor Andrew Leifer of Harvard University. © Society for Science & the Public 2000 - 2011

Lifting a Veil of Fear to See a Few Benefits of Fever

By PERRI KLASS, M.D. Fever is common, but fever is complicated. It brings up science and emotion, comfort and calculation. As a pediatrician, I know fever is a signal that the immune system is working well. And as a parent, I know there is something primal and frightening about a feverish child in the night. So those middle-of-the-night calls from worried parents, so frequent in every pediatric practice, can be less than straightforward. A recent paper in The Journal of the American Medical Association pointed out one reason, and a longstanding discussion about parental perceptions reminds us of the emotional context. The JAMA study looked at over-the-counter medications for children, including those marketed for treating pain and fever: how they are labeled, and whether the droppers and cups and marked spoons in the packages properly reflect the doses recommended on the labels. The article concluded that many medications are not labeled clearly, that some provide no dosing instrument, and that the instruments, if included, are not marked consistently. (A dosing chart might recommend 1.5 milliliters, but the dropper has no “1.5 ml” mark.) “Basically, the main message of the paper is that the instructions on the boxes and bottles of over-the-counter medications are really confusing,” said the lead author, Dr. H. Shonna Yin of New York University Medical Center, who is a colleague of mine and an assistant professor of pediatrics. © 2011 The New York Times Company

Related chapters from BP7e: Chapter 13: Homeostasis: Active Regulation of the Internal Environment
Related chapters from MM:Chapter 9: Homeostasis: Active Regulation of the Internal Environment
Link ID: 14856 - Posted: 01.11.2011

Images of Cell Type: Multipolar neuron

This project is supported by Award Number RC2GM092708 from the National Institute of General Medical Sciences (NIGMS).

Related chapters from BP7e: Chapter 2: Functional Neuroanatomy: The Nervous System and Behavior
Related chapters from MM:Chapter 2: Cells and Structures: The Anatomy of the Nervous System
Link ID: 14782 - Posted: 12.14.2010

The wonders of the cell go online

John Roach For many of us, the wonders of cell biology came alive when we peered through a microscope at an amoeba in science class. Today, a new online image library of cells brings that same sense of wonder and magic to anyone with an Internet connection. The library contains more than 1,000 images, videos, and animations of cells from a variety of organisms — from the Chinese hamster (Cricetulus griseus) to humans (Homo sapiens). The database aims to advance research on cellular activity with the ultimate goal of improving human health, according to the American Society for Cell Biology, which has created the database in partnership with Glencoe Software and the Open Microscopy Environment. "In our research of disease, one of the key features is to understand the mechanism of disease — and that is going to happen, in many cases, at the cellular level," David Orloff, manager of The Cell image library, told me. For example, the library will make it possible for scientists to compare different cell types online and understand the nature of specific cells and cellular processes, both normal and abnormal. This may lead to new discoveries about diseases, as well as new targets for drug development. © 2010 msnbc.com

Birds Do It ... We Do It ... and No One Knows Why

By NICHOLAS BAKALAR Everyone yawns, but no one knows why. We start when we are in the womb, and we do it through old age. Most vertebrate species, even birds and fishes, yawn too, or at least do something that looks very much like it. But its physiological mechanisms, its purpose and what survival value it might have remain a mystery. There is no shortage of theories — a recent article in the journal Neuroscience & Biobehavioral Reviews outlines many — but a dearth of experimental proof that any of them is correct. “The lack of experimental evidence is sometimes accompanied by passionate discussion,” said Dr. Adrian G. Guggisberg, the lead author. Hippocrates proposed in the fourth century B.C. that yawning got rid of “bad air,” and increased “good air” in the brain. The widely held modern view of this theory is that yawning helps increase blood oxygen levels and decrease carbon dioxide. If this were true, Dr. Guggisberg writes, then people would yawn more when they exercise. And people with lung or heart disease, who often suffer from a lack of oxygen, yawn no more than anyone else. Researchers have exposed healthy subjects to gas mixtures with high levels of carbon dioxide and found that it does not lead to increased yawning. In fact, there is no study that shows that oxygen levels in the brain are changed one way or the other by yawning. Copyright 2010 The New York Times Company

Related chapters from BP7e: Chapter 15: Emotions, Aggression, and Stress; Chapter 2: Functional Neuroanatomy: The Nervous System and Behavior
Related chapters from MM:Chapter 11: Emotions, Aggression, and Stress; Chapter 2: Cells and Structures: The Anatomy of the Nervous System
Link ID: 14776 - Posted: 12.14.2010

An Odyssey Through the Brain

By ABIGAIL ZUGER, M.D. Who has seen the mind? Neither you nor I — nor any of the legions of neuroscientists bent on opening the secrets of that invisible force, as powerful and erratic as the wind. The experts are definitely getting closer: the last few decades have produced an explosion of new techniques for probing the blobby, unprepossessing brain in search of the thinking, feeling, suffering, scheming mind. But the field remains technologically complicated, out of reach for the average nonscientist, and still defined by research so basic that the human connection, the usual “hook” by which abstruse science captures general interest, is often missing. Carl Schoonover took this all as a challenge. Mr. Schoonover, 27, is midway through a Ph.D. program in neuroscience at Columbia, and thought he would try to find a different hook. He decided to draw the general reader into his subject with the sheer beauty of its images. So he has compiled them into a glossy new art book. “Portraits of the Mind: Visualizing the Brain From Antiquity to the 21st Century,” newly published by Abrams, includes short essays by prominent neuroscientists and long captions by Mr. Schoonover — but its words take second place to the gorgeous imagery, from the first delicate depictions of neurons sketched in prim Victorian black and white to the giant Technicolor splashes the same structures make across 21st-century LED screens. Copyright 2010 The New York Times Company

Thrown off balance: Inner ear disorders are complex to diagnose and correct.

By Courtney Humphries Two years ago, George Winslow’s world was literally thrown off balance. He was working on cars at the auto repair shop he owns in Foxborough when he began to sweat, and every step felt like a struggle. The world began to spin violently. Unable to get his balance, Winslow slammed to the floor. He lost hearing in one ear. He left the shop in an ambulance, and the world didn’t stop moving for more than four grueling hours. Winslow was diagnosed with Meniere’s disease, a progressive disorder of the inner ear that brings severe, unexpected attacks of vertigo, often accompanied by hearing loss, ringing in the ears, and nausea. From then on, Winslow suffered from frequent attacks of intense dizziness, sometimes three or four a week. An active person who had always preferred to work under the hood rather than behind a desk, he was often exhausted and relying more on the help of his staff. “This is the toughest thing I’ve ever gone through,’’ says Winslow, 54. Because a balance disorder is a complex problem to diagnose, people who suffer them often go from doctor to doctor until, like Winslow, they find specialists who can properly treat the problem. After his local doctor offered little help, Winslow eventually found his way to Dr. Steven Rauch, an otologist at the Massachusetts Eye and Ear Infirmary who specializes in treating balance disorders like Meniere’s. Winslow has undergone a series of treatments that have lessened the frequency and duration of the attacks, and he had minor surgery last week that he hopes will further improve the situation. But although his condition has improved, he’s had to adjust to a life out of balance. © 2010 NY Times Co

Related chapters from BP7e: Chapter 9: Hearing, Vestibular Perception, Taste, and Smell
Related chapters from MM:Chapter 6: Hearing, Balance, Taste, and Smell
Link ID: 14695 - Posted: 11.22.2010

A Direct Hit of Drugs to Treat Brain Cancer

By DENISE GRADY It was a desperate measure, for a desperate disease. Fourteen months ago, Dennis Sugrue let doctors thread a fine tube through his blood vessels and up into his head, so they could spray the drug Avastin directly into the part of his brain where a tumor had been cut out. It was an experiment, devised mainly to find out whether the procedure was safe, and to gauge how much Avastin the brain could tolerate. But Mr. Sugrue, then 50, was hoping the experiment would also free him of cancer. He had glioblastoma, a brain tumor that fights off every known therapy. The same disease killed Senator Edward M. Kennedy last year. Mr. Sugrue’s cancer was diagnosed in April 2009 and bombarded with the usual weapons: surgery, radiation and chemotherapy. Within months, the tumor was growing back. That was when he signed up for the Avastin study. About 10,000 Americans a year develop glioblastoma. Nearly all find that the standard treatments seem to work — for a while. And then the clock starts to run down. With treatment, the median survival is about 15 months. Only 25 percent of patients make it to two years. The disease is the focus of much research, and will almost certainly be for years to come. Hundreds of studies are being conducted in glioblastoma and other brain cancers. Among other things, they involve vaccines, drug combinations and special drug-delivery techniques. Progress is measured in small steps — a few more months of survival, more patients managing to survive two years. On paper the gains may seem minute, but for patients the added time may translate into a graduation or wedding that might otherwise have been missed. Copyright 2010 The New York Times Company

Related chapters from BP7e: Chapter 2: Functional Neuroanatomy: The Nervous System and Behavior; Chapter 19: Language and Hemispheric Asymmetry
Related chapters from MM:Chapter 2: Cells and Structures: The Anatomy of the Nervous System; Chapter 15: Language and Our Divided Brain
Link ID: 14646 - Posted: 11.09.2010

Hacker’s challenge

by James Garvey So long as people read Wittgenstein, people will read Peter Hacker. It’s hard to imagine how his work on the monumental Analytical Commentary on Wittgenstein’s Philosophical Investigations could possibly be superseded. He spent nearly twenty years on that project (ten of them in cooperation with his friend and colleague Gordon Baker), following in Wittgenstein’s footsteps, and producing a large number of important articles and books on topics in the philosophy of mind and language along the way. Nearer the end than the beginning of a distinguished career as an Oxford don, at a time of life when most academics would be happy to leave the lectern behind and collapse somewhere with a nice glass of wine, Hacker is in the middle of another huge project, this time on human nature. He also seems keen to pick a fight with almost anyone doing the philosophy of mind. This has a much to do with his view of philosophy as a contribution to human understanding, not knowledge. One might think that philosophy has the same general aim as science – securing knowledge of ourselves and the world we live in – even if its subject matter is more abstract and its methods more armchair. What is philosophy if not an attempt to secure new knowledge about the mind or events or beauty or right conduct or what have you? According to Hacker, philosophy is not a cognitive discipline. It’s something else entirely. “Philosophy does not contribute to our knowledge of the world we live in after the manner of any of the natural sciences. You can ask any scientist to show you the achievements of science over the past millennium, and they have much to show: libraries full of well-established facts and well-confirmed theories. If you ask a philosopher to produce a handbook of well-established and unchallengeable philosophical truths, there’s nothing to show.” © 2010 TPM: The Philosophers’ Magazine.

Related chapters from BP7e: Chapter 1: Biological Psychology: Scope and Outlook; Chapter 18: Attention and Higher Cognition
Related chapters from MM:Chapter 1: An Introduction to Brain and Behavior; Chapter 14: Attention and Consciousness
Link ID: 14638 - Posted: 11.08.2010

Optogenetics: Controlling the Brain with Light [Extended Version]

By Karl Deisseroth Despite the enormous efforts of clinicians and researchers, our limited insight into psychiatric disease (the worldwide-leading cause of years of life lost to death or disability) hinders the search for cures and contributes to stigmatization. Clearly, we need new answers in psychiatry. But as philosopher of science Karl Popper might have said, before we can find the answers, we need the power to ask new questions. In other words, we need new technology. Developing appropriate techniques is difficult, however, because the mammalian brain is beyond compare in its complexity. It is an intricate system in which tens of billions of intertwined neurons—with multitudinous distinct characteristics and wiring patterns—compute with precisely timed, millisecond-scale electrical signals, as well as with a rich diversity of biochemical messengers. Because of that complexity, neuroscientists lack a deep grasp of what the brain is really doing—of how specific activity patterns within specific brain cells ultimately give rise to thoughts, feelings and memories. By extension, we also do not know how the brain's physical failures produce distinct psychiatric disorders such as depression or schizophrenia. The ruling paradigm of psychiatric disorders—casting them in terms of chemical imbalances and altered levels of neurotransmitters—does not do justice to the brain's high-speed electrical neural circuitry. And psychiatric treatments have historically been largely serendipitous: helpful for many but rarely illuminating, and suffering from the same challenges as basic neuroscience. In a 1979 Scientific American article Nobel laureate Francis Crick suggested that the major challenge facing neuroscience was the need to control one type of cell in the brain while leaving others unaltered. Electrical stimuli cannot meet this challenge because electrodes are too crude a tool: they stimulate all the circuitry at their insertion site without distinguishing between different cell types, and their signals cannot turn off neurons with precision. © 2010 Scientific American,

50 ideas to change science: Neuroscience

Thanks to better brain imaging and biological insights, we're closing in on the neurons of consciousness and the subtleties of our mental machinery Cognitive control Towards the seat of consciousness The question "what is consciousness?" represents one of the great frontiers of contemporary science. Thanks to studies of humans and animals, we now know that it is a subtly nuanced state whose nature and intensity varies according to the brain's intrinsic level of activity, its chemical microclimate and the information it receives from outside. By exploiting the normal vicissitudes of waking, sleeping and dreaming states, we are now beginning to explore how consciousness is expressed and controlled. For example, I have been involved in studies comparing brain activation in REM sleep with that in lucid-dreaming states, in which we retain much executive brain function. They seem to confirm the central importance of one specific area of the frontal brain - the dorsolateral prefrontal cortex - in regulating many key aspects of consciousness, including attention, decision-making and voluntary action. A combination of imaging techniques, judicious measures of subjective experience and detailed cellular and molecular-level studies will continue to deepen our understanding of our cognitive command centres in the coming years. With them we hope to crack the puzzle of consciousness, and perhaps correct the dysfunctional states of the brain we now call mental illness. Allan Hobson © Copyright Reed Business Information Ltd.

Guards of the blood-brain barrier identified

By Rachel Ehrenberg Of all the body’s organs, the brain is the most like Area 51: Entry to the region is severely restricted, thanks to a barricade of cells and molecules known collectively as the blood-brain barrier. Increased surveillance by scientists has now pinpointed the barrier’s senior operatives, cells that are tasked with monitoring the razor wire–like barricade that keeps all but a select few from entering the brain. In two papers published online October 13 in Nature, scientists report that specialized cells called perictyes are crucial in the blood-brain barrier’s development and its maintenance in adulthood. A better understanding of how these pericytes function could help elucidate why some people fare especially poorly after traumatic brain injury or get particular neurological diseases such as cerebral palsy, scientists say. And new research could also lead to tricks for selectively opening or closing the blood-brain barrier, letting in medications that might combat diseases such as Alzheimer’s. One of the new studies demonstrates that pericytes are necessary for cementing the barrier’s cells into a nearly impenetrable wall surrounding blood vessels in the central nervous system. The work also establishes a timeline: In mice, the blood-brain barrier develops well before birth, researchers from Stanford and the University of California, San Francisco report. Pericytes also appear to keep the barrier’s cells on lockdown, dialing down the activity of genes that, if left to their own devices, would spur the transport of molecules across the barrier and into the brain. © Society for Science & the Public 2000 - 2010

Inside Neurosurgery’s Rise

By RANDI HUTTER EPSTEIN, M.D. NEW HAVEN — Two floors below the main level of Yale’s medical school library is a room full of brains. No, not the students. These brains, more than 500 of them, are in glass jars. They are part of an extraordinary collection that might never have come to light if not for a curious medical student and an encouraging and persistent doctor. The cancerous brains were collected by Dr. Harvey Cushing, who was one of America’s first neurosurgeons. They were donated to Yale on his death in 1939 — along with meticulous medical records, before-and-after photographs of patients, and anatomical illustrations. (Dr. Cushing was also an accomplished artist.) His belongings, a treasure trove of medical history, became a jumble of cracked jars and dusty records shoved in various crannies at the hospital and medical school. Until now. In June 2010, after a colossal effort to clean and organize the material — 500 of 650 jars have been restored — the brains found their final resting place behind glass cases around the perimeter of the Cushing Center, a room designed solely for them. These chunks of brains floating in formaldehyde bring to life a dramatic chapter in American medical history. They exemplify the rise of neurosurgery and the evolution of 20th-century American medicine — from a slipshod trial-and-error trade to a prominent, highly organized profession. Copyright 2010 The New York Times Company

Related chapters from BP7e: Chapter 1: Biological Psychology: Scope and Outlook; Chapter 2: Functional Neuroanatomy: The Nervous System and Behavior
Related chapters from MM:Chapter 1: An Introduction to Brain and Behavior; Chapter 2: Cells and Structures: The Anatomy of the Nervous System
Link ID: 14396 - Posted: 08.24.2010

Can you teach yourself synaesthesia?

by Linda Geddes A form of synaesthesia in which people experience letters or numbers in colour may be trainable. The discovery could shed new light on how such traits develop. Synaesthesia is thought to have a genetic component, but some people have reported synaesthetic experiences following hypnosis, so Olympia Colizoli at the University of Amsterdam in the Netherlands, and colleagues, wondered if it might also be possible to acquire synaesthesia through training. To test the idea, they gave seven volunteers a novel to read in which certain letters were always written in red, green, blue or orange (see picture). Before and after reading the book, the volunteers took a "synaesthetic crowding" test, in which they identified the middle letter of a grid of black letters which were quickly flashed onto a screen. Synaesthetes perform better on the test when a letter they experience in colour is the target letter. The volunteers performed significantly better on this test after training compared with people who read the novel in black and white. The findings suggest that natural synaesthesia may develop as a result of childhood experiences as well as genetics, says Colizoli, who presented the findings at the Forum of European Neuroscience in Amsterdam last week. © Copyright Reed Business Information Ltd.

Related chapters from BP7e: Chapter 8: General Principles of Sensory Processing, Touch, and Pain
Related chapters from MM:Chapter 5: The Sensorimotor System
Link ID: 14252 - Posted: 07.13.2010

Alpha, beta, gamma: The language of brainwaves

by Helen Thomson I'VE just had a brainwave. Oh, and there's another. And another! In fact, you will have had thousands of them since you started reading this sentence. These waves of electricity flow around our brains every second of the day, allowing neurons to communicate while we walk, talk, think and feel. Exactly where brainwaves are generated in the brain, and how they communicate information, is something of a mystery. As we begin to answer these questions, surprising functions of these ripples of neural activity are emerging. It turns out they underpin almost everything going on in our minds, including memory, attention and even our intelligence. Perhaps most importantly, haphazard brainwaves may underlie the delusions experienced by people with schizophrenia, and researchers are investigating this possibility in the hope that it will lead to treatments for this devastating condition. So what exactly is a brainwave? Despite the way it is bandied about in everyday chit-chat, the term "brainwave" has a specific meaning in neuroscience, referring to rhythmic changes in the electrical activity of a group of neurons. Each neuron has a voltage, which can change when ions flow in or out of the cell. This is normally triggered by stimulation from another cell, and once a neuron's voltage has reached a certain point, it too will fire an electrical signal to other cells, repeating the process. When many neurons fire at the same time, we see these changes in the form of a wave, as groups of neurons are all excited, silent, then excited again, at the same time. © Copyright Reed Business Information Ltd.

Related chapters from BP7e: Chapter 3: Neurophysiology: The Generation, Transmission, and Integration of Neural Signals
Related chapters from MM:Chapter 3: Neurophysiology: The Generation, Transmission, and Integration of Neural Signals
Link ID: 14248 - Posted: 07.12.2010

Big Animals, Slower Reflexes

By SINDYA N. BHANOO It takes an elephant much longer to notice a fly and flick it away than it takes a shrew, and the reason is not that the elephant’s great brain is too busy with philosophy, or that it simply does not concern itself with flies. It’s a matter of round-trip travel time — in the nervous system. The trip from the elephant’s skin to the brain and back again to the muscles to flick the tail is 100 times as long as the same trip in a shrew, according to a new study published in the Proceedings of the Royal Society B. The nervous system acts like an information superhighway, sending messages back and forth from the brain throughout the body. The bigger the animal, the greater the distance traveled. Nerves have a maximum speed limit of about 180 feet per second, said Maxwell Donelan, the study’s lead author. “It makes sense that in a large animal, like an elephant, messages have a longer way to travel,” he said. Dr. Donelan believes that large animals may have to compensate for this handicap by thinking ahead, and avoiding risky situations. “That’s what we want to study next,” he said. “It could be that the nervous systems of large animals have evolved to become excellent predictive machines.” Copyright 2010 The New York Times Company

Man in �coma’ heard everything for 23 years

BRUSSELS - For 23 torturous years, Rom Houben says he lay trapped in his paralyzed body, aware of what was going on around him but unable to tell anyone or even cry out. The car-crash victim had been diagnosed as being in a vegetative state but appears to have been conscious the whole time. An expert using a specialized type of brain scan that was not available in the 1980s finally realized it, and unlocked Houben’s mind again. The 46-year-old Houben is now communicating with one finger and a special touchscreen on his wheelchair. “Powerlessness. Utter powerlessness. At first I was angry, then I learned to live with it,” he said, punching the message into the screen during an interview with the Belgian RTBF network, aired Monday. He has called his rescue his “renaissance.” Over the years, Houben’s family refused to accept the word of his doctors, firmly believing their son knew what was happening around him, and gave no thought to letting him die, said his mother, Fina. She was vindicated when the breakthrough came. “At that moment, you think, ‘Oh, my God. See, now you know.’ I was always convinced,” she said in a telephone interview with The Associated Press. The discovery took place three years ago but only recently came to light, after publication of a study on the misdiagnosis of people with consciousness disorders. Copyright 2009 The Associated Press.

Related chapters from BP7e: Chapter 1: Biological Psychology: Scope and Outlook; Chapter 19: Language and Hemispheric Asymmetry
Related chapters from MM:Chapter 1: An Introduction to Brain and Behavior; Chapter 15: Language and Our Divided Brain
Link ID: 13495 - Posted: 06.24.2010

Scientists see numbers inside people’s heads

By Charles Q. Choi By carefully analyzing brain activity, scientists can tell what number a person has just seen, research now reveals. They can similarly tell how many dots a person was presented with. Past investigations had uncovered brain cells in monkeys that were linked with numbers. Although scientists had found brain regions linked with numerical tasks in humans — the frontal and parietal lobes, to be exact — until now patterns of brain activity linked with specific numbers had proven elusive. Story continues below ↓advertisement | your ad here Scientists had 10 volunteers watch either numerals or dots on a screen while a part of their brain known as the intraparietal cortex was scanned — it's a region of the parietal lobe especially linked with numbers. They next rigorously analyzed brain activity to decipher which patterns might be linked with the numbers the volunteers had observed. When it came to small numbers of dots, the researchers found that brain activity patterns changed gradually in a way that reflected the ordered nature of the numbers. For example, one might be able to conclude that the pattern for six is between that for five and seven. In the case of the numerals, the researchers could not detect this same gradual change. This suggests their methods simply might not be sensitive enough to detect this progression yet, or that these symbols are, in fact, coded as more precise, discrete entities in the brain. © 2009 LiveScience.com.

Related chapters from BP7e: Chapter 19: Language and Hemispheric Asymmetry
Related chapters from MM:Chapter 15: Language and Our Divided Brain
Link ID: 13300 - Posted: 06.24.2010

When �What Animals Do’ Doesn’t Seem to Cover It

By NATALIE ANGIER Certain things should never be taken for granted, among them your spouse, your mother, the United States Constitution, and the precise meaning of words that are at the heart of your profession. Daniel Levitis was working as a teaching assistant for an animal behavior course at the University of California in Berkeley, and on the first day of class, the professor explained that the shorthand definition of a “behavior” is “what animals do.” O.K., that’s the freshman-friendly definition, Mr. Levitis thought. Now how about the unabridged, professional version? What is the point-by-point definition of a behavior that behavioral biologists use when judging whether a particular facet of the natural world falls under their purview? After all, animals digest food and grow fur, yet few behavioral researchers would count such physiological and anatomical doings as behaviors. Mr. Levitis asked the professor for the full definition of a behavior. She referred him to their textbook, with its promising title, “Animal Behavior.” To his surprise, neither that textbook nor any other reference he consulted bothered to spell it out. “It was assumed that everyone knew what the word meant,” said Mr. Levitis, who is completing his doctorate at Berkeley. Mr. Levitis decided to ask the people who should know best: working behavioral biologists. The provocative and crisply written results of his quest, carried out with his colleagues, William Lidicker Jr. and Glenn Freund, appear in the current issue of the journal Animal Behaviour. Among the highlights of the report: biologists don’t agree with one another on what a behavior is; biologists don’t agree with themselves on what a behavior is; biologists can be as parochial as the rest of us, meaning that animal behaviorists tend to reflexively claim the behavior label for animals only, while botanists sniff that, if the well-timed unfurling of a smelly, colorful blossom for the sake of throwing your seed around isn’t the ultimate example of a behavior, then there’s no such thing as Valentine’s Day; and, finally, words may count, but thoughts do not. Copyright 2009 The New York Times Company

Related chapters from BP7e: Chapter 1: Biological Psychology: Scope and Outlook
Related chapters from MM:Chapter 1: An Introduction to Brain and Behavior
Link ID: 13072 - Posted: 06.24.2010

Brain scans unravel hypnotist’s hand trick

How can a hypnotist paralyze your hand just with words? By making a part of your brain butt in on the process that normally makes your hand move, a study says. So the brain region that's ready to move your hand ignores its usual inputs and listens to this interloper, which says, "Don't even bother," the research concluded. It's "a kind of reconnection between different brain regions," said Yann Cojan, a researcher at the University of Geneva in Switzerland. He's an author of the study in Thursday's issue of the journal Neuron. It used brain scans to show what happened when 12 volunteers tried to move a hand that had been paralyzed by hypnosis. Results showed the right motor cortex prepared itself as usual to tell the left hand to move. But the cortex appeared to be ignoring the parts of the brain it normally communicates with in controlling movement. Instead, it acted more in sync than usual with a different brain region called the precuneus. That was a surprise, Cojan said. The precuneus is involved in mental imagery and memory about oneself. Cojan suggests it was brimming with the metaphors the participants had heard from the hypnotist: Your hand is very heavy, it is stuck on the table, etc. So, he said, it might have been telling the motor cortex, "Oh, but your hand is too heavy, you can't move your hand." It's as if the motor cortex "is connected to the idea that it cannot move (the hand) and so ... it doesn't send the message to move," Cojan said. For the research, 12 participants had their brains scanned while doing a task that required them to push a button with one hand or the other. For some sessions, they were hypnotized and told their left hands were paralyzed. For other sessions, their mental status was normal. For comparison, six other participants simply pretended their left hands were paralyzed. © 2009 The Associated Press.

Related chapters from BP7e: Chapter 11: Motor Control and Plasticity; Chapter 19: Language and Hemispheric Asymmetry
Related chapters from MM:Chapter 5: The Sensorimotor System; Chapter 15: Language and Our Divided Brain
Link ID: 12990 - Posted: 06.24.2010

Previous Page | Next Page

Links By Chapter:

Links for Keyword: Miscellaneous