Chapter 5. The Sensorimotor System

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By Ingrid Wickelgren An attractive blonde in a bright red blouse sits in a wheelchair before the assembled scientists, doctors, writers and members of the community. We are in a conference room at the Aspen Meadows Resort, the site of the 2013 Aspen Brain Forum. Amanda Boxtel recalls what life was like for her at 24. She had been a skier, a runner and a ballet dancer, she tells us. She liked to hike in the wilderness. Pictures of a beautiful young woman appear on a screen. In the photos, she’s standing. Then one day on a slope, the tips of Boxtel’s skis crossed. She did a somersault and shattered four vertebrae. “I also shattered illusions of my immortality. I was paralyzed from here”—she hold her hands at her hips—“down. No movement and no sensation.” That life changed radically for her right then is difficult to dispute. But Boxtel eventually embraced a road to recovery. “It took time to turn wounds into wisdom. It took guts. This is a cruel injury. It is so much more than not being able to walk,” she tells us. With the aid of adaptive technology, she got back on her skis. She took up waterskiing, rock climbing, kayaking and hang gliding. But still, she couldn’t bear weight on her legs or walk. Walking seems easy to most of us, because the action is built-in; it is automatic. In reality, however, walking is a highly complex motion involving many different muscles that must contract in a precisely timed sequence. Once the spinal cord can no longer orchestrate this motion, it is exceedingly hard to replicate. Walking, for Boxtel, was arguably a pipe dream. And so she sat for 21 years. © 2013 Scientific American

Keyword: Robotics
Link ID: 18699 - Posted: 09.25.2013

By NICHOLAS BAKALAR Many people use copper bracelets and magnetic wrist straps to alleviate the pain of arthritis, but a new randomized, double-blinded, placebo-controlled study concludes they do not work. British researchers randomized 65 patients with rheumatoid arthritis to receive one of four treatments: wearing a powerful magnetic wrist strap, a weak magnetic strap, a non-magnetic strap and a copper bracelet. Each patient wore each device for five weeks and completed pain surveys. The study appears in the September issue of PLoS One. The patients reported pain levels using a visual scale, ranging from “no pain” to “worst pain ever,” and recorded how often their joints felt tender and swollen. Researchers used questionnaires to assess physical limitations, and tested for inflammation by measuring blood levels of C-reactive protein and plasma viscosity. There was no statistically significant difference in any of these measures regardless of which type of device patients were wearing. Stewart J. Richmond, a researcher at the University of York who led the study, acknowledged that the devices may have some benefits as a placebo. “People swear by these things,” he said. “Is it ethically correct to allow patients to live in blissful ignorance? Or is it better to provide them with the facts? We can’t deceive patients. We have to be honest with them.” Copyright 2013 The New York Times Company

Keyword: Pain & Touch
Link ID: 18695 - Posted: 09.24.2013

By JOHN SCHWARTZ Candace Pert, a neuroscientist who helped discover a fundamental element of brain chemistry as a graduate student and went on to become a major proponent of alternative medicine, died on Sept. 12 at her home in Potomac, Md. She was 67. The cause was cardiac arrest, said her sister, Deane Beebe. Dr. Pert was working at the Johns Hopkins University School of Medicine in the 1970s when a team she was on found one of the most sought-after objects in brain research: the receptor in the brain that opiates like morphine fit into, like a key in a lock, allowing the drug’s effects to work. The discovery of the opioid receptor would, in 1978, earn the coveted Albert Lasker Award, often a precursor to the Nobel Prize. The award went to Solomon H. Snyder, who headed the lab. Neither Dr. Pert nor any of the other lab assistants was cited. Such omissions are common in the world of science; the graduate student in the lab rarely gets credit beyond being the first name on the papers describing the research. But Dr. Pert did something unusual: she protested, sending a letter to the head of the foundation that awards the prize, saying she had “played a key role in initiating the research and following it up” and was “angry and upset to be excluded.” Her letter caused a sensation in the field. Some saw her exclusion as an example of the burdens and barriers women face in science careers. In a 1979 article about Dr. Pert in the The Washington Post, Dr. Snyder, who had lauded Dr. Pert’s contributions in his Lasker acceptance speech, argued that “that’s the way the game is played,” adding that today’s graduate students will be tomorrow’s lab chiefs, and that “when they have students, it will be the same.” © 2013 The New York Times Company

Keyword: Pain & Touch
Link ID: 18685 - Posted: 09.21.2013

By William Saletan In much of this country, over the last three years, pro-lifers have banned abortions 20 weeks after fertilization. They’ve justified these bans by asserting—contrary to the most authoritative studies—that fetuses at this stage of development can feel pain. Their assertions, in turn, are based on research by several doctors. But the doctors don’t buy the pro-lifers’ conclusions. They say their research doesn’t support the bans. The 12 state bans (several of which have been blocked or limited by courts) begin with legislative “findings.” The findings parrot a 33-page report posted by the National Right to Life Committee and other pro-life organizations. The report cites the work of a number of researchers. Pam Belluck, an enterprising New York Times correspondent, contacted the researchers and asked them about the abortion bans. It turns out there’s a big gap between the science and the legislation. The pro-life report cites Dr. Nicholas Fisk, a former president of the International Fetal Medicine and Surgery Society, 27 times. According to the report, Fisk’s work shows fetal “stress responses” that imply sensitivity to pain. But Fisk tells Belluck that he doesn’t buy the inference from stress hormones and cerebral blood flow to pain. Neural studies, he says, have persuaded him that until 24 weeks gestation—the current abortion limit in many states—fetal pain “is not possible at all.” The report also cites Dr. Mark Rosen, a fetal anesthesia pioneer, 16 times. Rosen’s work, the report suggests, shows that painkillers and anesthesia are common during fetal surgery because unborn children can feel pain. But Rosen tells Belluck that the real purpose of such drugs during fetal surgery is to minimize dangerous movement and harmful stress hormones, thereby facilitating recovery. The drugs don’t signify medical belief in fetal pain. Dr. Scott Adzick, another fetal surgery expert cited in the pro-life report, makes the same point. © 2013 The Slate Group, LLC

Keyword: Pain & Touch; Aggression
Link ID: 18680 - Posted: 09.21.2013

By William Skaggs At the level of personal experience, there is nothing that seems easier to understand than pain. When I jam my finger in a doorway, I have no difficulty at all recognizing the sensation that results. But this superficial simplicity covers up a world of complexity at the level of brain mechanisms, and the complexities are even greater when we try to identify pain in other people or other species of animals. Some of the complexities are purely scientific, but others are caused by moral or philosophical issues getting mixed up with scientific issues. My provocation for writing this post was a blog post called Do Octopuses Feel Pain?, by Katherine Harmon, who writes the blog Octopus Chronicles, It’s basically a nice article—there’s nothing objectionable about it—but it pressed one of my buttons. She made a number of important points, and altogether what she wrote is well worth reading, but nevertheless the result left me with a feeling of dissatisfaction, as do most scientific discussions about pain in animals. I’d like to try to explain where that discomfort comes from. In her blog post, Harmon listed three elements that are involved in feeling pain: (1) nociception, that is, having mechanisms in the body that are capable of detecting damage and transmuting it into neural signals; (2) the experience of pain; (3) the ability to communicate pain information from sensation to perception. I’m not sure I understand the third aspect, but I take it to mean the ability to transform nociception into experience. In any case, the essence of pain as most people understand it is aspect 2. Most people think of pain as a particular type of experience—as something that happens inside our minds and can only be observed by ourselves. © 2013 Scientific American

Keyword: Pain & Touch
Link ID: 18679 - Posted: 09.21.2013

By Melissa Hogenboom Science reporter, BBC News Moving in time to a steady beat is closely linked to better language skills, a study suggests. People who performed better on rhythmic tests also showed enhanced neural responses to speech sounds. The researchers suggest that practising music could improve other skills, particularly speech. In the Journal of Neuroscience, the authors argue that rhythm is an integral part of language. "We know that moving to a steady beat is a fundamental skill not only for music performance but one that has been linked to language skills," said Nina Kraus, of the Auditory Neuroscience Laboratory at Northwestern University in Illinois. More than 100 teenagers were asked to tap their fingers along to a beat. Their accuracy was measured by how closely their responses matched the timing of a metronome. Next, in order to understand the biological basis of rhythmic ability, the team also measured the brainwaves of their participants with electrodes, a technique called electroencephalography. This was to observe the electrical activity in the brain in response to sound. Using this biological approach, the researchers found that those who had better musical training also had enhanced neural responses to speech sounds. In poorer readers this response was diminished. BBC © 2013

Keyword: Language; Aggression
Link ID: 18665 - Posted: 09.18.2013

The structure of the brain may predict whether a person will suffer chronic low back pain, according to researchers who used brain scans. The results, published in the journal Pain, support the growing idea that the brain plays a critical role in chronic pain, a concept that may lead to changes in the way doctors treat patients. The research was supported by the National Institute of Neurological Disorders and Stroke (NINDS), part of the National Institutes of Health. “We may have found an anatomical marker for chronic pain in the brain,” said Vania Apkarian, Ph.D., a senior author of the study and professor of physiology at Northwestern University Feinberg School of Medicine in Chicago. Chronic pain affects nearly 100 million Americans and costs the United States up to $635 billion per year to treat. According to the Institute of Medicine, an independent research organization, chronic pain affects a growing number of people. “Pain is becoming an enormous burden on the public. The U.S. government recently outlined steps to reduce the future burden of pain through broad-ranging efforts, including enhanced research,” said Linda Porter, Ph.D, the pain policy advisor at NINDS and a leader of NIH’s Pain Consortium. “This study is a good example of the kind of innovative research we hope will reduce chronic pain which affects a huge portion of the population.” Low back pain represents about 28 percent of all causes of pain in the United States; about 23 percent of these patients suffer chronic, or long-term, low back pain.

Keyword: Pain & Touch
Link ID: 18663 - Posted: 09.18.2013

By PAM BELLUCK It is a new frontier of the anti-abortion movement: laws banning abortion at 20 weeks after conception, contending that fetuses can feel pain then. Since 2010, a dozen states have enacted them, most recently Texas. Nationally, a bill passed the Republican-dominated House of Representatives in June. The science of fetal pain is highly complex. Most scientists who have expressed views on the issue have said they believe that if fetuses can feel pain, the neurological wiring is not in place until later, after the time when nearly all abortions occur. Several scientists have done research that abortion opponents say shows that fetuses can feel pain at 20 weeks after conception. One of those scientists said he believed fetuses could likely feel pain then, but he added that he believed the few abortions performed then could be done in ways to avoid pain. He and two other scientists said they did not think their work or current evidence provided scientific support for fetal-pain laws. Some scientists’ views have evolved as more research has been done. Dr. Nicholas Fisk, a senior maternal-fetal medicine specialist at Royal Brisbane and Women’s Hospital in Australia, said he once considered early fetal pain “a major possibility” after finding that fetuses receiving blood transfusions produced increased stress hormones and blood flow to the brain, and that painkillers lowered those levels. But Dr. Fisk, a former president of the International Fetal Medicine and Surgery Society, said neurological research has convinced him that pain “is not possible at all” before 24 weeks. © 2013 The New York Times Company

Keyword: Pain & Touch; Aggression
Link ID: 18659 - Posted: 09.17.2013

By Associated Press, Former Grateful Dead drummer Mickey Hart has a new piece of equipment accompanying him on his latest tour: a cap fitted with electrodes that capture his brain activity and direct the movements of a light show while he’s jamming on stage. The sensor-studded headgear is an outgrowth of collaboration between Hart, 70, and Adam Gazzaley, a University of California at San Francisco neuroscientist who studies cognitive decline. The subject has been an interest of the musician’s since the late 1980s, as he watched his grandmother deal with Alzheimer’s disease. When he played the drums for her, he says, she became more responsive. Since then, Hart has invested time and money exploring the therapeutic potential of rhythm. Thirteen years ago, he founded Rhythm for Life, a nonprofit promoting drum circles for the elderly. Hart first publicly wore his electroencephalogram cap last year at an AARP convention where he and Gazzaley discussed their joint pursuit of research on the link between brain waves and memory. He wore it again while making his new album, “Superorganism,” translating the rhythms of his brain waves into music. Hart’s bandmates, with input from other researchers in Gazzaley’s lab, paired different waves with specific musical sequences that were then inserted into songs. © 1996-2013 The Washington Post

Keyword: Brain imaging; Aggression
Link ID: 18656 - Posted: 09.17.2013

by Andy Coghlan A girl who does not feel physical pain has helped researchers identify a gene mutation that disrupts pain perception. The discovery may spur the development of new painkillers that will block pain signals in the same way. People with congenital analgesia cannot feel physical pain and often injure themselves as a result – they might badly scald their skin, for example, through being unaware that they are touching something hot. By comparing the gene sequence of a girl with the disorder against those of her parents, who do not, Ingo Kurth at Jena University Hospital in Germany and his colleagues identified a mutation in a gene called SCN11A. This gene controls the development of channels on pain-sensing neurons. Sodium ions travel through these channels, creating electrical nerve impulses that are sent to the brain, which registers pain. Overactivity in the mutated version of SCN11A prevents the build-up of the charge that the neurons need to transmit an electrical impulse, numbing the body to pain. "The outcome is blocked transmission of pain signals," says Kurth. To confirm their findings, the team inserted a mutated version of SCN11A into mice and tested their ability to perceive pain. They found that 11 per cent of the mice with the modified gene developed injuries similar to those seen in people with congenital analgesia, such as bone fractures and skin wounds. They also tested a control group of mice with the normal SCN11A gene, none of which developed such injuries. © Copyright Reed Business Information Ltd.

Keyword: Pain & Touch; Aggression
Link ID: 18649 - Posted: 09.16.2013

Insect leg cogs a first in animal kingdom Philip Ball If you are a young plant hopper, leaping one metre in a single bound, you need to push off with both hind legs in perfect unison or you might end up in a spin. Researchers have discovered that this synchrony is made possible by toothed gears that connect the two legs when the insects jump. Zoologists Malcolm Burrows and Gregory Sutton at the University of Cambridge, UK, say that this seems to be the first example in nature of rotary motion with toothed gears. They describe their findings today in Science1. When the insect jumps, the cog teeth join so that the two legs lock together, ensuring that they thrust at exactly the same time (see video above and image at left). “The gears add an extra level of synchronization beyond that which can be achieved by the nervous system,” says Burrows. Infant plant hoppers, known as nymphs, can take off in just 2 milliseconds, reaching take-off speeds of almost 4 metres a second (see video below). For motions this rapid, some mechanical device is needed to keep the legs synchronized and to avoid lopsided jumps that might lead to the insects spinning out of control. The problem does not, however, arise in all jumping insects: whereas the attachments of plant hoppers' hind legs are adjacent to each other, the legs of grasshoppers and fleas attach to opposite the sides of the body and move in parallel planes. This helps to stabilize the insects and even enables them to jump one-legged. © 2013 Nature Publishing Group

Keyword: Miscellaneous
Link ID: 18644 - Posted: 09.14.2013

Amanda Fiegl What's the difference between a spicy meal and being tickled? Not much, from your lips' perspective. A new study reports that Szechuan pepper activates the same nerves that respond to a light physical touch. Researchers at the University College London Institute of Cognitive Neuroscience found that people experienced the same sensation when either Szechuan pepper—a spice used in many types of Asian cuisine—or a machine vibrating at a particular frequency was placed on their lips. "The pepper is sending the same information to the brain as having a buzzer on your lips," the study's lead author, Nobuhiro Hagura, said in an email. The study, published today in Proceedings of the Royal Society B with the wry headline "Food Vibrations," delves into the little-known field of psychophysics, which "describes the relation between physical reality and what we actually perceive," Hagura said. "Our research shows just one interesting example of a case where we perceive something quite different than what is actually there," he said. "In many cases, the difference between perception and reality can be explained by understanding how the nervous system transmits information about the outside world to the brain." Previous studies have shown that other spicy ingredients, such as chili peppers and mustard oils, activate the nerve fibers associated with pain and physical heat. And studies in animals indicated that the spicy chemical in Szechuan pepper—sanshool—acts on the nervous system's "light touch" fibers. So Hagura and his colleagues wanted to find out whether sanshool produces a conscious sensation of touch in humans. © 1996-2013 National Geographic Society.

Keyword: Pain & Touch; Aggression
Link ID: 18633 - Posted: 09.11.2013

By Michele Solis Like truth and beauty, pain is subjective and hard to pin down. What hurts one moment might not register the next, and our moods and thoughts color the experience of pain. According to a report in April in the New England Journal of Medicine, however, researchers may one day be able to measure the experience of pain by scanning the brain—a much needed improvement over the subjective ratings of between one and 10 that patients are currently asked to give. Led by neuroscientist Tor Wager of the University of Colorado at Boulder, researchers used functional MRI on healthy participants who were given heated touches to their arm, some pleasantly warm, others painfully hot. During the painful touches, a scattered group of brain regions consistently turned on. Although these regions have been previously associated with pain, the new study detected a striking and consistent jump in their activity when people reported pain, with much greater accuracy than previous studies had attained. This neural signature appeared in 93 percent of subjects reporting to feel painful heat, ramping up as pain intensity increased and receding after participants took a painkiller. The researchers determined that the brain activity specifically marked physical pain rather than a generally unpleasant experience, because it did not emerge in people shown a picture of a lover who had recently dumped them. Although physical pain and emotional pain involve some of the same regions, the study showed that fine-grained differences in activation separate the two conditions. © 2013 Scientific American

Keyword: Pain & Touch; Aggression
Link ID: 18632 - Posted: 09.11.2013

By Athena Andreadis Recently, two studies surfaced almost simultaneously that led to exclamations of “Vulcan mind meld!”, “Zombie armies!” and “Brains in jars!” One is the announcement by Rajesh Rao and Andrea Stocco of Washington U. that they “achieved the first human-to-human brain interface”. The other is the Nature paper by Madeline Lancaster et al about stem-cell-derived “organoids” that mimic early developmental aspects of the human cortex. My condensed evaluation: the latter is far more interesting and promising than the former, which doesn’t quite do what people (want to) think it’s doing. The purported result of brain interfacing hit many hot buttons that have been staples of science fiction and Stephen King novels: primarily telepathy, with its fictional potential for non-consensual control. Essentially, the sender’s EEG (electroencephalogram) output was linked to the receiver’s TMS (transcranial magnetic stimulation) input. What the experiment actually did is not send a thought but induce a muscle twitch; nothing novel, given the known properties of the two technologies. The conditions were severely constrained to produce the desired result and I suspect the outcome was independent of the stimulus details: the EEG simply recorded that a signal had been produced and the TMS apparatus was positioned so that a signal would elicit a movement of the right hand. Since both sender and receiver were poised over a keyboard operating a video game, the twitch was sufficient to press the space bar, programmed by the game to fire a cannon. © 2013 Scientific American

Keyword: Robotics
Link ID: 18623 - Posted: 09.10.2013

by Nancy Shute It was hard to ignore those headlines saying that people with migraine have brain damage, even if you're not among the 12 percent or so who do suffer from these painful, recurring headaches. Don't panic, says the neurologist whose work sparked those alarming headlines. "It's still not something to stay up nights worrying about," says Dr. Richard Lipton, director of the Montefiore Headache Center in New York. But knowing about the brain anomalies that Lipton and his colleagues found might help people reduce their stroke risk. Some people who get do have a slightly . And some of the brain changes identified in the study look like mini-strokes. "On the MRI they look like very tiny strokes," Lipton tells Shots. But the people aren't having any stroke symptoms. Still, Lipton is convinced that the process is the same. "We now know it's a risk factor for these very small silent strokes," he says. The scientists evaluated data from 19 studies in which people with migraine headaches got MRI scans of their brains. Just about everybody is going to have some abnormalities show up in a scan. But the people who had migraines were more likely to have two common abnormalities: white matter abnormalities and infarct-like lesions. The were published in the journal Neurology. ©2013 NPR

Keyword: Pain & Touch; Aggression
Link ID: 18593 - Posted: 09.02.2013

By Katherine Harmon The past couple posts have described some pretty severe experiments on octopuses, including: showing how octopus arms can grow back after inflicted damage and how even severed octopus arms can react to stimuli. (For the record, animals in the studies were anesthetized and euthanized, respectively.) Without getting too far into the woods (or reefs) of animal treatment ethics, the question remains: How much pain and distress can these relatively short-lived invertebrates experience? Luckily for us, a new paper deals with that very question. Researchers from Europe, the UK and Japan teamed up to explore what we know about pain, perception and cognition in octopuses. The findings are described in the special “Cephalopod Research” issue of September’s Journal of Experimental Marine Biology and Ecology. And the issue is not just philo-scientific cloud (or wave) gazing. Starting this year the European Union asks researchers to make similarly humane accommodations for cephalopods as they do for vertebrates (Directive 2010/63/EU, pdf). But, do octopuses experience would-be painful experiences the same way mice do? As the researchers note in their paper, we know very little about whether cephalopods recognize pain or experience suffering and distress in a similar way that we humans—or even we vertebrates—do. Previous (as well as much current) research has looked largely to behavioral clues as an indication to an octopus’s internal state. For example, researchers have observed an octopus’s color changing and activity patterns and looked for any self-inflicted harm (swimming into the side of a tank or eating its own arms) to judge whether the animal is “stressed.” And to tell whether an animal has “gone under” anesthesia, they often look for movements, lack of response, posture change or, at the most, measure heart rate and breathing. © 2013 Scientific American

Keyword: Pain & Touch; Aggression
Link ID: 18585 - Posted: 08.31.2013

American researchers say they’ve performed what they believe is the first ever human-to-human brain interface, where one person was able to send a brain signal to trigger the hand motions of another person. “It was both exciting and eerie to watch an imagined section from my brain get translated into actual action by another brain,” said Rajesh Rao, a professor of computer science and engineering at the University of Washington, in a statement. Previous studies have done brain-to-brain transmissions between rats and one was done between a human and a rat. Rao was able to send a brain signal through the internet – utilizing electrical brain recordings and a form of magnetic stimulation – to the other side of the university campus to his colleague Andrea Stocco, an assistant professor of psychology, triggering Stocco’s finger to move on a keyboard. “The internet was a way to connect computers, and now it can be a way to connect brains,” said Stocco. “We want to take the knowledge of a brain and transmit it directly from brain to brain.” On Aug. 12, Rao sat in his lab with a cap on his head. The cap had electrodes hooked up to an electroencephalography machine, which reads the brain’s electrical activity. Meanwhile, Stocco was at his lab across campus, wearing a similar cap which had a transcranial magnetic stimulation coil place over his left motor cortex – the part of the brain that controls hand movement. Rao looked at a computer and in his mind, he played a video game. When he was supposed to fire a cannon at a target, he imagined moving his right hand, which stayed motionless. Stocco, almost instantaneously, moved his right index finger to push the space bar on the keyboard in front of him. Only simple brain signals, not thoughts “This was basically a one-way flow of information from my brain to his,” said Rao. © CBC 2013

Keyword: Robotics; Aggression
Link ID: 18583 - Posted: 08.29.2013

By GRETCHEN REYNOLDS As a clinical psychologist and sleep researcher at the Feinberg School of Medicine at Northwestern University, Kelly Glazer Baron frequently heard complaints from aggrieved patients about exercise. They would work out, they told her, sometimes to the point of exhaustion, but they would not sleep better that night. Dr. Baron was surprised and perplexed. A fan of exercise for treating sleep problems, but also a scientist, she decided to examine more closely the day-to-day relationship between sweat and sleep. What she and her colleagues found, according to a study published last week in The Journal of Clinical Sleep Medicine, is that the influence of daily exercise on sleep habits is more convoluted than many of us might expect and that, in the short term, sleep might have more of an impact on exercise than exercise has on sleep. To reach that conclusion, Dr. Baron and her colleagues turned to data from a study of exercise and sleep originally published in 2010. For that experiment, researchers had gathered a small group of women (and one man) who had received diagnoses of insomnia. The volunteers were mostly in their 60s, and all were sedentary. Then the researchers randomly assigned their volunteers either to remain inactive or to begin a moderate endurance exercise program, consisting of three or four 30-minute exercise sessions a week, generally on a stationary bicycle or treadmill, that were performed in the afternoon. This exercise program continued for 16 weeks. At the end of that time, the volunteers in the exercise group were sleeping much more soundly than they had been at the start of the study. They slept, on average, about 45 minutes to an hour longer on most nights, waking up less often and reporting more vigor and less sleepiness. Copyright 2013 The New York Times Company

Keyword: Sleep
Link ID: 18575 - Posted: 08.28.2013

By Katherine Harmon The eight wily arms of an octopus can help the animal catch dinner, open a jar and even complete a convincing disguise. But these arms are not entirely under the control of the octopus’s brain. And new research shows just how deep their independence runs—even when they are detached. The octopus’s nervous system is a fascinating one. Some two thirds of its neurons reside not in its central brain but out in its flexible, stretchable arms. This, researchers suspect, lightens the cognitive coordination demands and allows octopuses to let their arms do some of the “thinking”—or at least the coordination, problem-solving and reaction—on their own. And these arms can continue reacting to stimuli even after they are no longer connected to the main brain; in fact, they remain responsive even after the octopus has been euthanized and the arms severed. The research is in the special September 2013 issue of the Journal of Experimental Marine Biology and Ecology called “Cephalopod Biology” (we’ll check out the other fascinating studies in days and weeks ahead). The researchers, working at St. George’s University of London and the Anton Dohrn Zoological Station in Naples, Italy, examined 10 adult common octopuses (Octopus vulgaris) that had been collected and used for other studies. After the animals were euthanized, their arms were removed and kept in chilled seawater for up to an hour until they were ready for experimentation. Some arms were suspended vertically, and others were laid out horizontally. When pinched, suspended arms recoiled from the unpleasant stimulus by shortening and curling in a corkscrew shape within one second. © 2013 Scientific American

Keyword: Miscellaneous
Link ID: 18573 - Posted: 08.28.2013

By Felicity Muth Humans love their victory displays. You only have to watch a game of football (or soccer to US-readers) to see some victory displays of the most ridiculous kind. Why do people do such things? If there was no crowd there, it is unlikely that they would perform such displays. But is it for the sake of the sex they are wishing to attract, or perhaps to put people they are competing with in no doubt of their accomplishment? Other animals, of course, also compete with each other, for food, resources and mates. And, like humans, how they behave once they win or lose a competition may depend on who’s around to see it. Male spring crickets fight with each other for territories and females Male spring field crickets fight with other males. The winners tend to do a lot better with the lady crickets, as the winners may gain the best territory, and because females of this species prefer dominant males. Now for the part that may surprise you: the males that win these fights will perform a victory display just like humans – after beating another male, the male winner performs an aggressive song and jerks his body in a particular way to show off that he’s won this fight. But, like with humans, the question arises: why do males do these victory displays? Is it to show the loser male that he has lost, or to show other males and females that he’s won? © 2013 Scientific American

Keyword: Sexual Behavior; Aggression
Link ID: 18569 - Posted: 08.27.2013