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By Ben Thomas 2013’s Nobel prize in Physiology or Medicine honors three researchers in particular – but what it really honors is thirty-plus years of work not only from them, but also from their labs, their graduate students and their collaborators. Winners James Rothman, Randy Schekman and Thomas Südhof all helped assemble our current picture of the cellular machinery that enables neurotransmitter chemicals to travel from one nerve cell to the next. And as all three of these researchers agree, that process of understanding didn’t catalyze until the right lines of research, powered by the right tools, happened to converge at the right time. Long before that convergence, though, these three scientists began by seeking the answers to three different questions – none of which seemed to have anything to do with the others. When James Rothman started out as a researcher at Harvard in 1978, his goal was to find out exactly how vesicle transmission worked. Vesicles – Latin for “little vessels” – are the microscopic capsules that carry neurotransmitter molecules like serotonin and dopamine from one brain cell to another. By the late 1960s, the old-guard biochemist George Palade, along with other researchers, had already deduced that synaptic vesicles are necessary for neurotransmission – but the questions of which proteins guided these tiny vessels on their journey, and how they docked with receiving neurons, remained mysterious. Yale University's James Rothman set out to break down the process of vesicle transmission, chemical-by-chemical, reaction-by-reaction. Courtesy of Yale University. In other words, although researchers had established the existence of this vesicle transmission process, no one knew exactly what made it work, or how. © 2013 Scientific American

Related chapters from BP7e: Chapter 3: Neurophysiology: The Generation, Transmission, and Integration of Neural Signals; Chapter 4: The Chemistry of Behavior: Neurotransmitters and Neuropharmacology
Related chapters from MM:Chapter 3: Neurophysiology: The Generation, Transmission, and Integration of Neural Signals; Chapter 4: The Chemistry of Behavior: Neurotransmitters and Neuropharmacology
Link ID: 19022 - Posted: 12.11.2013

by Bethany Brookshire When neurons throughout the brain and body send messages, they release chemical signals. These chemicals, neurotransmitters, pass into the spaces between neurons, or synapses, binding to receptors to send a signal along. When they are not in use, neurotransmitters are stored within the cell in tiny bubbles called vesicles. During signaling, these vesicles head to the membrane of the neuron, where they dump neurotransmitter into the synapse. And after delivering their cargo, most vesicles disappear. But more vesicles keep forming, filling with neurotransmitters so neurons can keep sending signals. What goes up must come down. When vesicles go out, they must come back. But how fast to the vesicles re-appear? Must faster, it turns out, than we first thought. Neurotransmission happens fast. An electrical signal comes down a neuron in your brain and triggers vesicles to move to the cell membrane. When the vesicles merge into the membrane and release their chemical cargo, the neurotransmitters float across the open synapse to the next neuron. This happens every time the neuron “fires.” This needs to happen very quickly, as neurons often fire at 100 hertz, or 100 times per second. Some neurons perform a “kiss-and-run,” opening up a temporary pore in the membrane, releasing a little bit of neurotransmitter and darting away again. Other vesicles need to merge with the synapse entirely. With the assistance of docking proteins, these vesicles fuse with the membrane of the neuron to release the neurotransmitters, a process called exocytosis. © Society for Science & the Public 2000 - 2013.

Related chapters from BP7e: Chapter 3: Neurophysiology: The Generation, Transmission, and Integration of Neural Signals; Chapter 4: The Chemistry of Behavior: Neurotransmitters and Neuropharmacology
Related chapters from MM:Chapter 3: Neurophysiology: The Generation, Transmission, and Integration of Neural Signals; Chapter 4: The Chemistry of Behavior: Neurotransmitters and Neuropharmacology
Link ID: 19021 - Posted: 12.11.2013

To expedite research on brain disorders, the National Institutes of Health is shifting from a limited funding role to coordinating a Web-based resource for sharing post-mortem brain tissue. Under a NIH NeuroBioBank initiative, five brain banks will begin collaborating in a tissue sharing network for the neuroscience community. “Instead of having to seek out brain tissue needed for a study from scattered repositories, researchers will have one-stop access to the specimens they need,” explained Thomas Insel, M.D., director of NIH’s National Institute of Mental Health (NIMH), one of three NIH institutes underwriting the project. “Such efficiency has become even more important with recent breakthrough technologies, such as CLARITY and resources such as BrainSpan that involve the use of human tissue.” Historically, NIH institutes have awarded investigator-initiated grants to support disease-specific brain bank activities. The NIH NeuroBioBank instead employs contracts, which affords the agency a more interactive role. Contracts totaling about $4.7 million for the 2013 fiscal year were awarded to brain banks at the Mount Sinai School of Medicine, New York City; Harvard University in Cambridge, Mass., the University of Miami; Sepulveda Research Corporation, Los Angeles; and the University of Pittsburgh. These brain and tissue repositories seek out and accept brain donations, store the tissue, and distribute it to qualified researchers seeking to understand the causes of – and identify treatments and cures for – brain disorders, such as schizophrenia, multiple sclerosis, depression, epilepsy, Down syndrome and autism.

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: 18992 - Posted: 12.03.2013

By DONALD G. McNEIL Jr. The World Health Organization has approved a new vaccine for a strain of encephalitis that kills thousands of children and leaves many survivors with permanent brain damage. The move allows United Nations agencies and other donors to buy it. The disease, called Japanese encephalitis or brain fever, is caused by a mosquito-transmitted virus that can live in pigs, birds and humans. Less than 1 percent of those infected get seriously ill, but it kills up to 15,000 children a year and disables many more. Up to four billion people, from southern Russia to the Pacific islands, are at risk; it is more prevalent near rice paddies. There is no cure. The low-cost vaccine, approved last month, is the first authorized by the agency for children and the first Chinese-made vaccine it has approved. It is made by China National Biotec Group and was tested by PATH, a nonprofit group in Seattle with funding from the Bill and Melinda Gates Foundation. Dr. Margaret Chan, W.H.O.’s director-general, said she hoped that approval would encourage other vaccine makers from China and elsewhere to enter the field. China had given the vaccine domestically to 200 million children over many years but had never sought W.H.O. approval. India, which previously bought 88 million doses from China, launched the first locally produced version last month. © 2013 The New York Times Company

Related chapters from BP7e: Chapter 11: Motor Control and Plasticity
Related chapters from MM:Chapter 5: The Sensorimotor System
Link ID: 18872 - Posted: 11.05.2013

/ by Charles Choi, LiveScience Using lasers, scientists can now surgically blast holes thinner than a human hair in the heads of live fruit flies, allowing researchers to see how the flies' brains work. Microscopically peering into living animals can help scientists learn more about key details of these animals' biology. For instance, tiny glass windows surgically implanted into the sides of living mice can help researchers study how cancers develop in real time and evaluate the effectiveness of potential medicines. Surgically preparing small live animals for such "intravital microscopy" is often time-consuming and requires considerable skill and dexterity. Now, Supriyo Sinha, a systems engineer at Stanford University in California, and his colleagues have developed a way to prepare live animals for such microscopy that is both fast -- taking less than a second -- and largely automated. To conduct this procedure, scientists first cooled fruit flies to anesthetize them. Then, the researchers carefully picked up the insects with tweezers and glued them to the tops of glass fibers in order to immobilize the flies' bodies and heads. Then, using a high-energy pulsed ultraviolet laser, the researchers blasted holes measuring 12 to 350 microns wide in the flies' heads. (In comparison, the average human hair is about 100 microns wide.) They then applied a saline solution to exposed tissue to help keep the fly brains healthy. © 2013 Discovery Communications, LLC.

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: 18861 - Posted: 11.02.2013

By KATE MURPHY Whether it’s hitting a golf ball, playing the piano or speaking a foreign language, becoming really good at something requires practice. Repetition creates neural pathways in the brain, so the behavior eventually becomes more automatic and outside distractions have less impact. It’s called being in the zone. But what if you could establish the neural pathways that lead to virtuosity more quickly? That is the promise of transcranial direct current stimulation, or tDCS — the passage of very low-level electrical current through targeted areas of the brain. Several studies conducted in medical and military settings indicate tDCS may bring improvements in cognitive function, motor skills and mood. Some experts suggest that tDCS might be useful in the rehabilitation of patients suffering from neurological and psychological disorders, perhaps even in reducing the time and expense of training healthy people to master a skill. But the research is preliminary, and now there is concern about a growing do-it-yourself community, many of them video gamers, who are making tDCS devices with nine-volt batteries to essentially jump-start their brains. “If tDCS is powerful enough to do good, you have to wonder if, done incorrectly, it could cause harm,” said Dr. H. Branch Coslett, chief of the cognitive neurology section at the University of Pennsylvania School of Medicine and a co-author of studies showing that tDCS improves recall of proper names, fosters creativity and improves reading efficiency. Even the tDCS units used in research are often little more than a nine-volt battery with two electrodes and a controller for setting the current and the duration of the session. Several YouTube videos show how to make a rough facsimile. © 2013 The New York Times Company

Related chapters from BP7e: Chapter 3: Neurophysiology: The Generation, Transmission, and Integration of Neural Signals; Chapter 2: Functional Neuroanatomy: The Nervous System and Behavior
Related chapters from MM:Chapter 3: Neurophysiology: The Generation, Transmission, and Integration of Neural Signals; Chapter 2: Cells and Structures: The Anatomy of the Nervous System
Link ID: 18848 - Posted: 10.29.2013

Henry Astley In the Mark Twain story The Celebrated Jumping Frog of Calaveras County, a frog named Daniel Webster "could get over more ground at one straddle than any animal of his breed you ever see." Now, scientists have visited the real Calaveras County in hopes of learning more about these hopping amphibians. They’ve found that what they see in the lab doesn’t always match the goings-on in the real world. If you wanted to know how far the bullfrog Rana catesbeiana could jump, the scientific literature would give you one answer: 1.295 meters, published in Smithsonian Contributions to Zoology in 1978. If you looked at the Guinness Book of World Records, though, you'd find a different answer. In 1986, a bullfrog called Rosie the Ribeter covered 6.55 meters in three hops. If you divide by three, at least one of those hops had to be no shorter than 2.18 meters—about four bullfrog body lengths more than the number in the scientific paper. The disparity matters. If bullfrogs can hop only 1.3 meters, they have enough power in their muscles to pull off the jump without any other anatomical help. But if they can jump farther, they must also be using a stretchy tendon to power their hops—an ability that other frogs have but that researchers thought bullfrogs had lost. These particular amphibians, scientists speculated, might have made some kind of evolutionary tradeoff that shortened their jumps but enabled them to swim better in the water, where they spend much of their lives. © 2013 American Association for the Advancement of Science

Related chapters from BP7e: Chapter 11: Motor Control and Plasticity
Related chapters from MM:Chapter 5: The Sensorimotor System
Link ID: 18800 - Posted: 10.17.2013

By Sandra G. Boodman, Janet Ruddock was crushed: She had dreamed of greeting her first grandchild, and now that once-in-a-lifetime experience had been marred by the embarrassing problem that had derailed her life for nearly a decade. In June 2010, Ruddock, then 59, and her husband had flown to Vancouver, B.C., from Washington to meet their new grandson. But soon after they arrived, Ruddock’s in­trac­table sweating went into overdrive. As she sat in a rocking chair, perspiration drenched her head and upper body, soaking her shirt and dripping onto the 4-week-old infant. “I burst into tears,” Ruddock recalled. “All I can remember is the feeling that I’m wet, this poor baby’s wet and a moment you should always remember is ruined. You’re never going to get it back. “ For Ruddock, that event precipitated a suicidal depression. For the previous eight years she had undergone tests, taken drugs and endured the bafflement — and skepticism — of a parade of doctors she consulted about the extreme, unpredictable sweating that engulfed her head and upper body. After confiding her despair to a relative, she began seeing a psychiatrist. By chance, a few months later she learned about a woman whose experience mirrored her own and provided her a much-needed road map. “It’s a fascinoma,” said retired Washington internist Charles Abrams, using the medical slang for an unusual — or unusually interesting — case. “You usually hate for patients to come in and say, ‘I found this on the Internet,’ ” said Abrams, who treated Ruddock until his retirement last year. “But every once in a while, something is brought to your attention.” © 1996-2013 The Washington Post

Related chapters from BP7e: Chapter 2: Functional Neuroanatomy: The Nervous System and Behavior; Chapter 15: Emotions, Aggression, and Stress
Related chapters from MM:Chapter 2: Cells and Structures: The Anatomy of the Nervous System; Chapter 11: Emotions, Aggression, and Stress
Link ID: 18787 - Posted: 10.15.2013

by Colin Barras SHAKEN, scorched and boiled in its own juices, this 4000-year-old human brain has been through a lot. It may look like nothing more than a bit of burnt log, but it is one of the oldest brains ever found. Its discovery, and the story now being pieced together of its owner's last hours, offers the tantalising prospect that archaeological remains could harbour more ancient brain specimens than thought. If that's the case, it potentially opens the way to studying the health of the brain in prehistoric times. Brain tissue is rich in enzymes that cause cells to break down rapidly after death, but this process can be halted if conditions are right. For instance, brain tissue has been found in the perfectly preserved body of an Inca child sacrificed 500 years ago. In this case, death occurred at the top of an Andean mountain where the body swiftly froze, preserving the brain. However, Seyitömer Höyük – the Bronze Age settlement in western Turkey where this brain was found – is not in the mountains. So how did brain tissue survive in four skeletons dug up there between 2006 and 2011? Meriç Altinoz at Haliç University in Istanbul, Turkey, who together with colleagues has been analysing the find, says the clues are in the ground. The skeletons were found burnt in a layer of sediment that also contained charred wooden objects. Given that the region is tectonically active, Altinoz speculates that an earthquake flattened the settlement and buried the people before fire spread through the rubble. © Copyright Reed Business Information Ltd.

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: 18741 - Posted: 10.05.2013

Ballet dancers develop differences in their brain structures to allow them to perform pirouettes without feeling dizzy, a study has found. A team from Imperial College London said dancers appear to suppress signals from the inner ear to the brain. Dancers traditionally use a technique called "spotting", which minimises head movement. The researchers say their findings may help patients who experience chronic dizziness. Dizziness is the feeling of movement when, in reality, you are still. For most it is an occasional, temporary sensation. But around one person in four experiences chronic dizziness at some point in their life. When someone turns or spins around rapidly, fluid in the vestibular organs of the inner ear can be felt moving through tiny hairs. Once they stop, the fluid continues to move, which can make a person feel like they are still spinning. Ballet dancers train hard to be able to spin, or pirouette, rapidly and repeatedly. They use a technique called spotting, focusing on a spot on the floor - as they spin, their head should be the last bit to move and the first to come back. In the study, published in the journal Cerebral Cortex, the team recruited 29 female ballet dancers and 20 female rowers of similar age and fitness levels. BBC © 2013

Related chapters from BP7e: Chapter 9: Hearing, Vestibular Perception, Taste, and Smell; Chapter 11: Motor Control and Plasticity
Related chapters from MM:Chapter 6: Hearing, Balance, Taste, and Smell; Chapter 5: The Sensorimotor System
Link ID: 18709 - Posted: 09.28.2013

Maggie Fox NBC News School officials in an area near New Orleans have shut off water fountains and stocked up on hand sanitizer this week after a brain-eating amoeba killed a 4-year-old boy and was found thriving in the local tap water system. Water officials say they are “shocking” the St. Bernard Parish system with chlorine to try to kill off the parasite and get the water back up to a safe standard. And while health experts say the water is perfectly safe to drink, some school officials are taking no chances. They’ve shut off water fountains until they are certain. Dr. Raoult Ratard, the Louisiana state epidemiologist, says the devastation wrought by Hurricane Katrina in 2005 may ultimately be to blame. Low-lying St. Bernard Parish, where the boy who died was infected while playing on a Slip ‘N Slide, was badly hit by the flooding that Katrina caused. “After Katrina, it almost completely depopulated,” Ratard told NBC News. “You have a lot of vacant lots and a lot of parts of the system where water is sitting there under the sun and not circulating.” That, says Ratard, provided a perfect opportunity for the amoeba to multiply. Without enough chlorine to kill them, they can spread. The Centers for Disease Control and Prevention said on Monday that it had found Naegleria fowleri in St. Bernard’s water supply – the first time it’s ever been found in U.S. tap water. The amoeba likes hot water and thrives in hot springs, warm lakes and rivers.

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: 18662 - Posted: 09.18.2013

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

Related chapters from BP7e: Chapter 11: Motor Control and Plasticity
Related chapters from MM:Chapter 5: The Sensorimotor System
Link ID: 18644 - Posted: 09.14.2013

By Laura Sanders Rats spent hours in a state of chilly suspended animation after researchers injected a compound into the animals in a cold room. The animals’ heart rates slowed, brain activity became sluggish and body temperature plummeted. The research joins a small number of studies that attempt to induce the metabolically lethargic state known as torpor in animals that can’t normally slow their metabolism. “It’s a breakthrough” in understanding aspects of torpor, says neuroscientist Kelly Drew of the University of Alaska Fairbanks. Lowering the body temperature of a nonhibernating mammal is really hard, says Domenico Tupone of Oregon Health & Science University in Portland. As temperatures inside the body fall, several failsafe systems spring into action. Blood vessels near the skin squeeze tight to hold warmth in, the body starts to shiver and brown fat, a tissue that’s especially plentiful in newborns, starts to produce heat. But Tupone and colleagues bypassed the rats’ defenses against the cold with a compound that’s similar to adenosine, a molecule in the body that signals sleepiness. After about an hour in a room chilled to 15° Celsius, the rats grew lethargic. Their brain waves slowed, their blood pressure dropped and their heart grew sluggish, occasionally skipping beats. The rats’ core temperature dropped from about 38° to about 30° C, or 80° Fahrenheit, the authors report in the Sept. 4 Journal of Neuroscience. Tupone and his colleagues measured even lower temperatures in further experiments — rats’ core body temperature reached 15° C or about 57° F. “That is a pretty amazing temperature. No one has done this before,” he says. © Society for Science & the Public 2000 - 2013

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: 18609 - Posted: 09.05.2013

By Felicity Muth In my previous post, I talked about how crickets were influenced by who was watching them when they performed a victory dance after winning a fight. Although this is a unique finding, it fits into a larger picture of many animals (including insects) being affected by their social context. At the animal behaviour conference I went to in Colorado (where I heard both about the cricket research and about the study I’m going to write about today), you could see how people were affected by what others were doing around them. When one person sneaked out before the end of a talk to go to a talk in a different room, a load of other people would follow. When chatting with a friend, a person would modify what they were saying depending on who else was in the vicinity. Whether we are aware of it all of the time or not, we constantly modify our behaviour depending on the social context we’re in. Well, in addition to crickets, it turns out that honeybees are affected by social context too. This isn’t surprising, given that these bees are highly social animals, but quite how they are affected is rather interesting. Honeybees live in colonies of up to 40, 000 – 80, 000 individuals, almost all females. Like humans, honeybees like to keep their dwelling at constant temperature, not least to make sure that their brood can develop. Unlike humans however, bees think around 36°C (96.8°F) is a great temperature to have their home at. In the winter, honeybees shiver to produce heat, pressing their abdomens against their brood (stored in cells) to distribute the heat more evenly. In the summer however, it can get pretty hot, and so the bees use some strategies to cool down that are not dissimilar to our own. They collect water that can evaporate in the colony and cool it down. They also fan to circulate air around the colony. However, until recently it was not clear how bees decide to start fanning, and whether this might be influenced by what others are doing. © 2013 Scientific American

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: 18586 - Posted: 08.31.2013

Karen Ravn It’s safe to say that wildlife biologist Lynn Rogers gets along better with the black bears in Minnesota than with the humans in the state’s Department of Natural Resources. Rogers, a popular bear researcher who has made numerous TV appearances, is engaged in quite a row with the department. At issue: should the department renew Rogers’ permit to study black bears? In June, the department said “no.” But trying to come between Rogers and his bears is a bit like trying to come between a mother bear and her cubs. He took the agency to court, and late last month, the parties came to a temporary agreement. Rogers can keep radio collars on the ten research bears that have them now, but he can’t keep live-streaming video on the Internet from his internationally popular den cams. His case will go back to court in six to nine months. Earlier this month, Rogers received a big boost from renowned chimpanzee researcher Jane Goodall, who wrote to Minnesota governor Mark Dayton praising Rogers and saying that it would be “a scientific tragedy” if his research were ended now. The department gave three reasons for not renewing Rogers’ permit: he hadn’t produced any peer-reviewed publications based on data collected over the past 14 years when he had a permit; his work was endangering the public; and he had engaged in unprofessional conduct. © 2013 Nature Publishing Group

Related chapters from BP7e: Chapter 1: Biological Psychology: Scope and Outlook; Chapter 6: Evolution of the Brain and Behavior
Related chapters from MM:Chapter 1: An Introduction to Brain and Behavior
Link ID: 18577 - Posted: 08.29.2013

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

Related chapters from BP7e: Chapter 11: Motor Control and Plasticity
Related chapters from MM:Chapter 5: The Sensorimotor System
Link ID: 18573 - Posted: 08.28.2013

By Scicurious Optogenetics likes to light up debate. Optogenetics is a hot technique in neuroscience research right now, involving taking a light-activited gene (called a channel rhodopsin) targeted into a single neuron type, and inserting it into the genome of, say, a mouse (yes, we can do this now). When you then shine a light into the mouse’s brain, the channel rhodopsin responds, and the neurons that are now expressing the channel rhodopsin fire. This means that you can get a single type of neuron to fire (or not, there are ones that inhibit firing, too), whenever you want to, merely by turning on a light. I actually remember where I WAS when I first heard of optogenetics. I came into the lab in the morning, was going about my daily business, and hadn’t checked the daily Tables of Contents for journals yet (I get these delivered into my email). I remember the postdoc, normally a pretty phlegmatic person, actually putting a little excitement into their voice, “hey guys, look at this.” The paper was this one. We all crowded around. It took us all a few minutes to “get it”. As it began to sink it, I had two thoughts. The first? “WHOA, THAT IS AWESOME.” The second? “Great, I know what’s going to be the hot stuff now.” There are fashions in science. Not the kind where everyone dyes their lab coat plaid or creates cutoffs out of their Personal Protective Equipment (though that would be hilarious). There are experimental fashions. Lesions were once really “in”. Knockouts were hot stuff in the 90s. fMRI enjoyed (and still does enjoy) its moment in the sun, electrophysiology often adds a little je ne sais quoi to a paper. DREADDs, CLARITY. And when a new thing comes along and is going to be hot? You can sniff it out a mile away. For next year? I’m betting on GEVIs, myself. They’ll be all the rage. © 2013 Scientific American

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: 18565 - Posted: 08.27.2013

By April Neale An innovative two-part series, "Brains on Trial with Alan Alda," airing Wednesday, September 11 and 18, 2013, 10-11 p.m. on PBS (check local listings), explores how the growing ability to separate truth from lies, even decode people’s thoughts and memories, may radically affect how criminal trials are conducted in the future. As brain scanning techniques advance, their influence in criminal cases is becoming critically important. Brains on Trial centers around the trial of a fictional crime: a robbery staged in a convenience store that has been filmed by the store’s security cameras. A teenager stands accused of the attempted murder of the store clerk’s wife who was shot during the crime. While the crime is fictional, the trial is conducted before a real federal judge and argued by real practicing attorneys. The program is divided into two-parts: the first hour examines the guilt phase of the trial concluding with the jury’s verdict; the second hour looks at the sentencing phase, when arguments for and against a severe sentence are heard. As the trial unfolds, Alda visits with neuroscientists whose research has already influenced some Supreme Court decisions, as well as Duke University law professor Nita Farahany, a member of the Presidential Commission for the Study of Bioethical Issues. On these visits, neuroscientists show how functional MRIs and other brain scanning techniques are exploring lie detection, facial recognition, memory decoding, racial bias, brain maturity, intention, and even emotions. The research Alda discovers is at the center of a controversy as to how this rapidly expanding ability to peer into people’s minds and decode their thoughts and feelings could – or should – affect trials like the one presented in the program. As DNA evidence has played a major role in exonerating innocent prisoners, Brains on Trial asks if neuroscience can make the criminal justice system more just.

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: 18527 - Posted: 08.20.2013

By Neuroskeptic Back in April a paper came out in Nature Reviews Neuroscience that shocked many: Katherine Button et al’s Power failure: why small sample size undermines the reliability of neuroscience It didn’t shock me, though, skeptic that I am: I had long suspected that much of neuroscience (and science in general) is underpowered – that is, that our sample sizes are too small to give us an acceptable chance of detecting the signals that we claim to be able to isolate out of the noise. In fact, I was so unsurprised by Button et al that I didn’t even read it, let alone write about it, even though the authors list included such neuro-blog favorites as John Ionaddis, Marcus Munafo and Brian Nosek (I try to avoid obvious favouritism, you see). However this week I took a belated look at the paper, and I noticed something interesting. Button et al took 49 meta-analyses and calculated the median observed statistical power of the studies in each analysis. The headline finding was that average power is small. I was curious to know why it was small. So I correlated the study characteristics (sample size and observed effect size) with the median power of the studies. I found that median power in a given meta-analysis was not correlated with the median sample size of those studies (d on the left, RR on the right):

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: 18487 - Posted: 08.12.2013

Brain cells talk to each other in a variety of tones. Sometimes they speak loudly but other times struggle to be heard. For many years scientists have asked why and how brain cells change tones so frequently. Today National Institutes of Health researchers showed that brief bursts of chemical energy coming from rapidly moving power plants, called mitochondria, may tune brain cell communication. “We are very excited about the findings,” said Zu-Hang Sheng, Ph.D., a senior principal investigator and the chief of the Synaptic Functions Section at the NIH’s National Institute of Neurological Disorders and Stroke (NINDS). “We may have answered a long-standing, fundamental question about how brain cells communicate with each other in a variety of voice tones.” The network of nerve cells throughout the body typically controls thoughts, movements and senses by sending thousands of neurotransmitters, or brain chemicals, at communication points made between the cells called synapses. Neurotransmitters are sent from tiny protrusions found on nerve cells, called presynaptic boutons. Boutons are aligned, like beads on a string, on long, thin structures called axons. They help control the strength of the signals sent by regulating the amount and manner that nerve cells release transmitters. Mitochondria are known as the cell’s power plant because they use oxygen to convert many of the chemicals cells use as food into adenosine triphosphate (ATP), the main energy that powers cells. This energy is essential for nerve cell survival and communication. Previous studies showed that mitochondria can rapidly move along axons, dancing from one bouton to another.

Related chapters from BP7e: Chapter 3: Neurophysiology: The Generation, Transmission, and Integration of Neural Signals; Chapter 4: The Chemistry of Behavior: Neurotransmitters and Neuropharmacology
Related chapters from MM:Chapter 3: Neurophysiology: The Generation, Transmission, and Integration of Neural Signals; Chapter 4: The Chemistry of Behavior: Neurotransmitters and Neuropharmacology
Link ID: 18414 - Posted: 07.27.2013