Chapter 3. Neurophysiology: The Generation, Transmission, and Integration of Neural Signals

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James Hamblin The past two weeks have been frenetic for Bre Hushaw, who is now known to millions of people as the girl in the depression helmet. Hushaw has been hearing from people all around the world who want to try it, or at least want to know how it works. Her life as a meme began when she agreed to an on-camera interview with the local-news site AZfamily.com for a story headlined “Helmet Approved by FDA to Treat Depression Available in Arizona.” The feel-good tale of Hushaw’s miraculous recovery from severe depression was tossed into the decontextualizing maw of the internet and distilled down to a screenshot of a young woman looking like a listless Stormtrooper. Jokes poured in. Some of the most popular, each with more than 100,000 likes on Twitter, include: “If u see me with this ugly ass helmet mind ur business.” “Friend: hey everything alright? Me, wearing depression helmet: yeah I’m just tired.” “The depression helmet STAYS ON during sex.” Hushaw has been tracking the virality, sometimes cringing and sometimes laughing. She replies to as many serious inquiries as she can, while finishing up her senior year at Northern Arizona University before starting a job in marketing. A year ago, she didn’t think she was going to live to graduation. When she was 10 years old, her mother died. Her depression symptoms waxed and waned from then on, and they waxed especially when she heard the gunshots on her campus during a shooting at the school in 2015. She’s tried many medications over the years—14, by her count. (c) 2019 by The Atlantic Monthly Group.

Keyword: Depression
Link ID: 26163 - Posted: 04.22.2019

By Benedict Carey More than 3 million Americans live with disabling brain injuries. The vast majority of these individuals are lost to the medical system soon after their initial treatment, to be cared for by family or to fend for themselves, managing fatigue, attention and concentration problems with little hope of improvement. On Saturday, a team of scientists reported a glimmer of hope. Using an implant that stimulates activity in key areas of the brain, they restored near-normal levels of brain function to a middle-aged woman who was severely injured in a car accident 18 years ago. Experts said the woman was a test case, and that it was far from clear whether the procedure would prompt improvements for others like her. That group includes an estimated 3 million to 5 million people, many of them veterans of the wars in Iraq and Afghanistan, with disabilities related to traumatic brain injuries. “This is a pilot study,” said Dr. Steven R. Flanagan, the chairman of the department of rehabilitation medicine at NYU Langone Health, who was not part of the research team. “And we certainly cannot generalize from it. But I think it’s a very promising start, and there is certainly more to come in this work.” The woman, now in her early 40s, was a student when the accident occurred. She soon recovered sufficiently to live independently. But she suffered from persistent fatigue and could not read or concentrate for long, leaving her unable to hold a competitive job, socialize much, or resume her studies. “Her life has changed,” said Dr. Nicholas Schiff, a professor of neurology and neuroscience at Weill Cornell Medicine and a member of the study team. “She is much less fatigued, and she’s now reading novels. The next patient might not do as well. But we want keep going to see what happens.” © 2019 The New York Times Company

Keyword: Brain Injury/Concussion
Link ID: 26142 - Posted: 04.15.2019

Alix Spiegel Our thoughts and fears, movements and sensations all arise from the electrical blips of billions of neurons in our brain. Streams of electricity flow through neural circuits to govern these actions of the brain and body, and some scientists think that many neurological and psychiatric disorders may result from dysfunctional circuits. As this understanding has grown, some scientists have asked whether we could locate these faulty circuits, reach deep into the brain and nudge the flow to a more functional state, treating the underlying neurobiological cause of ailments like tremors or depression. The idea of changing the brain for the better with electricity is not new, but deep brain stimulation takes a more targeted approach than the electroconvulsive therapy introduced in the 1930s. DBS seeks to correct a specific dysfunction in the brain by introducing precisely timed electric pulses to specific regions. It works by the action of a very precise electrode that is surgically inserted deep in the brain and typically controlled by a device implanted under the collarbone. Once in place, doctors can externally tailor the pulses to a frequency that they hope will fix the faulty circuit. This week's Invisibilia podcast features the story of a woman with obsessive-compulsive disorder and depression who signed up for a deep brain stimulation trial. The story describes what it's like to be able to adjust her mood by adjusting the settings on her device. Listen to that story here. © 2019 npr

Keyword: Depression; Emotions
Link ID: 26096 - Posted: 03.30.2019

Alix Spiegel We have the story of one woman who is taking part in an experiment on deep brain stimulation. RACHEL MARTIN, HOST: We are about to go deep - deep into your brain. STEVE INSKEEP, HOST: With a story about deep brain stimulation, or DBS, which sounds like a kind of massage, actually. But it means that patients get an implant that delivers small pulses of electricity to their brains. MARTIN: It's often used to treat Parkinson's disease. But for years, researchers have been trying to figure out how to use it to treat psychiatric disorders. INSKEEP: Results and experiments so far have been mixed. Many patients see no benefit. But some with obsessive-compulsive disorder have seen big changes. MARTIN: Like the next woman you're going to meet. For privacy, we are withholding her last name. Alix Spiegel from NPR's INVISIBILIA has her story. ALIX SPIEGEL, BYLINE: During the appointment, Megan didn't have to do that much, just sit in a chair while one of the doctors from the experiment used what looked like an oversized remote control to reprogram her electricity levels. Even after five years of having the implant, getting her electricity adjusted was unpredictable. Sometimes it went fine. But having electrodes in your brain is really complicated. And occasionally, the adjustments didn't go well. UNIDENTIFIED DOCTOR: While you were talking, I slowly ramped it up again. Anything different now? MEGAN: Slightly more aware. UNIDENTIFIED DOCTOR: OK. MEGAN: It's not like in the past, where it was like, oh, I feel good. But it's, like, a different feeling. SPIEGEL: After the doctor turned her up higher, Megan said she felt better. But then he decided to dial it back just a notch. He was worried that too much electricity might make her manic. UNIDENTIFIED DOCTOR: Now, if you notice me turning it down, then maybe I'll change my mind on that. MEGAN: (Crying) I'm sorry; don't do it. UNIDENTIFIED DOCTOR: Did you just feel it? MEGAN: (Crying) I don't feel very good at all right now. © 2019 npr

Keyword: Depression
Link ID: 26095 - Posted: 03.30.2019

By James Gallagher Health and science correspondent, BBC News French scientists say they have proof that dogs can pick up the smell of an epileptic seizure. The University of Rennes team hope the findings could lead to ways to predict when people will have a seizure. These could include dogs or "electronic noses" that pick up the precise odour being given off during a seizure. Dogs have previously been shown to be able to sniff out diseases including cancers, Parkinson's, malaria and diabetes. Some people with epilepsy already rely on the animals. One sleeping in a child's bedroom can alert family members of a seizure in the middle of the night. The latest study, in the journal Scientific Reports, trained five dogs from Medical Mutts, in the US, to recognise the smell of sweat taken from a patient having a seizure. They were then given a choice of seven sweat samples taken from other patients while they were either relaxing, exercising or having a seizure. Two of the dogs found the seizure sample about two-thirds of the time and the other three were 100% accurate The report says: "The results are extremely clear and constitute a first step towards identifying a seizure-specific odour." © 2019 BBC

Keyword: Chemical Senses (Smell & Taste); Epilepsy
Link ID: 26091 - Posted: 03.29.2019

By Adrian Cho BOSTON—MRI scanners can map a person's innards in exquisite detail, but they say little about composition. Now, physicists are pushing MRI to a new realm of sensitivity to trace specific biomolecules in tissues, a capability that could aid in diagnosing Alzheimer's and other diseases. The advance springs not from improved scanners, but from better methods to solve a notoriously difficult math problem and extract information already latent in MRI data. The new techniques, described this month at a meeting of the American Physical Society here, could soon make the jump to the clinic, says Shannon Kolind, a physicist at the University of British Columbia (UBC) in Vancouver, Canada, who is using them to study multiple sclerosis (MS). "I don't think I'm being too optimistic to say that will happen in the next 5 years," she says. Sean Deoni, a physicist at Brown University, says that "any scanner on the planet can do this." An MRI scanner uses magnetic fields and radio waves to tickle the nuclei of hydrogen atoms—protons—in molecules of water, which makes up more than half of soft tissue. The protons act like little magnets, and the scanner's strong magnetic field makes them all point in one direction. A pulse of radio waves then tips the protons away from the magnetic field, causing them to twirl en masse, like so many gyroscopes. The protons then radiate radio waves of their own. © 2019 American Association for the Advancement of Scienc

Keyword: Brain imaging; Multiple Sclerosis
Link ID: 26059 - Posted: 03.21.2019

Hadley Freeman Like everyone else at this point, I have many questions about Brexit, starting with “why” and going from there. For example: are concerns about how Britain is going to cope merely “project fear”, as some Brexity folk still have it? Is it going to be like the blitz, as other Brexity people have promised enthusiastically? Such people include someone called Ant Middleton from Channel 4’s SAS: Who Dares Wins, who said last year in a tweet (since deleted): “A ‘no deal’ for our country would actually be a blessing in disguise. It would force us into hardship and suffering which would unite & bring us together, bringing back British values of loyalty and a sense of community!” Truly, there are few things as touching as a grown man playing soldiers by waxing nostalgic for a time he didn’t live through. And by “touching” I mean “nauseating”. I try to avoid writing about Brexit for the same reason I avoid eating my hair: you just end up choking on the pointlessness of it all. But one question has become too pressing to ignore: just how self-centred do you have to be to think the risk of making it harder for people to get necessary medications is an irrelevant niggle while you achieve your masturbatory fantasy of “sovereignty”? Sure, talk of insulin supplies, say, is a bummer when you are entertaining dreams of sailing victoriously back from Brussels beneath a St George’s flag, like George Washington crossing the Delaware in Emanuel Leutze’s painting, only less American (although, given that our supermarkets may soon be stuffed with chlorinated chicken from the US, maybe not). But for those who have long been dependent on certain drugs, these niggly questions make a no-deal Brexit less of a blessing in disguise. © 2019 Guardian News & Media Limited

Keyword: Epilepsy
Link ID: 26020 - Posted: 03.09.2019

Bret Stetka As the story goes, nearly 80 years ago on the Faroe Islands - a stark North Atlantic archipelago 200 miles off the coast of Scotland — a neurologic epidemic may have washed, or rather convoyed, ashore. Before 1940 the incidence of multiple sclerosis on the Faroes was near, if not, zero, according to the tantalizing lore I recall from medical school. Yet in the years following British occupation of the islands during World War II, the rate of MS rose dramatically, leading many researchers to assume the outbreak was caused by some unknown germ transmitted by the foreign soldiers. We now know that MS is not infectious in the true sense of the word. It is not contagious in the way, say, the flu is. But infection does likely play a role in MS. As may be the case in Alzheimer's disease, it's looking more and more like MS strikes when infectious, genetic and immune factors gang up to eventually impair the function of neurons in the brain and spinal cord. Researchers are hoping to better understand this network of influences to develop more effective ways to treat MS, and perhaps prevent it in the first place. In the MS-free brain, electrical impulses zip down nerve fibers called axons causing the release of neurotransmitters. The wiring allows neurons to communicate with each other and generate biologic wonders like thought, sensation and movement. In many regions of the brain those axons are encased in an insulating jacket of protein and fat called myelin, which increases the speed that electrical nerve impulses travel. © 2019 npr

Keyword: Multiple Sclerosis; Neuroimmunology
Link ID: 25893 - Posted: 01.22.2019

Laura Sanders Using laser light, ballooning tissue and innovative genetic tricks, scientists are starting to force brains to give up their secrets. By mixing and matching powerful advances in microscopy and cell biology, researchers have imaged intricate details of individual nerve cells in fruit flies and mice, and even controlled small groups of nerve cells in living mice. The techniques, published in two new studies, represent big steps forward for understanding how the brain operates, says molecular neuroscientist Hongkui Zeng of the Allen Institute for Brain Science in Seattle. “Without this kind of technology, we were only able to look at the soup level,” in which diverse nerve cells, or neurons, are grouped and analyzed together, she says. But the new studies show that nerve cells can be studied individually. That zoomed-in approach will begin to uncover the tremendous diversity that’s known to exist among cells, says Zeng, who was not involved in the research. “That is where the field is going. It’s very exciting to see that technologies are now enabling us to do that,” she says. These novel abilities came from multiple tools. At Howard Hughes Medical Institute’s Janelia Research Campus in Ashburn, Va., physicist Eric Betzig and his colleagues had developed a powerful microscope that can quickly peer deep into layers of brain tissue. Called a lattice light sheet microscope, the rig sweeps a thin sheet of laser light down through the brain, revealing cells’ structures. But like any microscope, it hits a wall when structures get really small, unable to resolve the most minute aspects of the scene. |© Society for Science & the Public 2000 - 2019.

Keyword: Brain imaging
Link ID: 25878 - Posted: 01.18.2019

By Kelly Servick In multiple sclerosis (MS), a disease that strips away the sheaths that insulate nerve cells, the body’s immune cells come to see the nervous system as an enemy. Some drugs try to slow the disease by keeping immune cells in check, or by keeping them away from the brain. But for decades, some researchers have been exploring an alternative: wiping out those immune cells and starting over. The approach, called hematopoietic stem cell transplantation (HSCT), has long been part of certain cancer treatments. A round of chemotherapy knocks out the immune system and an infusion of stem cells—either from a patient’s own blood or, in some cases, that of a donor—rebuilds it. The procedure is already in use for MS and other autoimmune diseases at several clinical centers around the world, but it has serious risks and is far from routine. Now, new results from a randomized clinical trial suggest it can be more effective than some currently approved MS drugs. “A side-by-side comparison of this magnitude had never been done,” says Paolo Muraro, a neurologist at Imperial College London who has also studied HSCT for MS. “It illustrates really the power of this treatment—the level of efficacy—in a way that’s very eloquent.” Nearly 30 years ago, when hematologist Richard Burt saw how HSCT worked in patients with leukemia and lymphoma, he was struck by a curious effect: After those patients rebuilt their immune systems, their childhood vaccines no longer protected them, recalls Burt, now at Northwestern University’s Feinberg School of Medicine in Evanston, Illinois. Without a new vaccination, the new immune cells wouldn’t recognize viruses such as measles and mumps and launch a prompt counterattack. That suggested that in the case of an autoimmune disease, reseeding the immune system might help the body “forget” that its own cells were the enemy. © 2018 American Association for the Advancement of Science

Keyword: Multiple Sclerosis
Link ID: 25870 - Posted: 01.16.2019

Abby Olena In the never-ending search for ways to help people eat healthy, scientists have been looking into brain stimulation, specifically, sending a weak electrical current to the brain through two scalp electrodes—a technique called transcranial direct current stimulation. It has previously shown promise in limiting both food cravings and consumption in people, but in a study published yesterday (January 9) in Royal Society Open Science, researchers didn’t find any effects of tDCS on food-related behavior, indicating that the technique’s use needs another look. “The good things about the study are the large sample size and the fact that it’s fairly rigorous,” says Mark George, a psychiatrist and neurologist at the Medical University of South Carolina who did not participate in the study. “The problem [is] interpreting studies where there’s a failure to find. All you can say is that it didn’t work . . . with this group.” During tDCS, one to two milliamps of electricity—enough to feel tingles or pins and needles, but far less than the 800 or so milliamps used for electroconvulsive therapy—are delivered to the brain. Over the last two decades, scientists have reported targeting the technique to the dorsolateral prefrontal cortex, a brain area that’s been shown to be involved in food-related behavior. They’ve found it has helped people crave less and, to a lesser extent, eat fewer sweets and other tempting foods. Yet these experiments have generally included groups of 20 or fewer people, and other studies have failed to replicate their effects. © 1986 - 2019 The Scientist.

Keyword: Obesity
Link ID: 25861 - Posted: 01.14.2019

By Kara Manke A new neurostimulator developed by engineers at UC Berkeley can listen to and stimulate electric current in the brain at the same time, potentially delivering fine-tuned treatments to patients with diseases like epilepsy and Parkinson’s. The device, named the WAND, works like a “pacemaker for the brain,” monitoring the brain’s electrical activity and delivering electrical stimulation if it detects something amiss. These devices can be extremely effective at preventing debilitating tremors or seizures in patients with a variety of neurological conditions. But the electrical signatures that precede a seizure or tremor can be extremely subtle, and the frequency and strength of electrical stimulation required to prevent them is equally touchy. It can take years of small adjustments by doctors before the devices provide optimal treatment. WAND, which stands for wireless artifact-free neuromodulation device, is both wireless and autonomous, meaning that once it learns to recognize the signs of tremor or seizure, it can adjust the stimulation parameters on its own to prevent the unwanted movements. And because it is closed-loop — meaning it can stimulate and record simultaneously — it can adjust these parameters in real-time. © 2019 UC Regents;

Keyword: Epilepsy
Link ID: 25830 - Posted: 01.01.2019

By Kimon de Greef CAPE TOWN — A musician from South Africa had a tumor in his brain, so doctors opened a hole in his skull to remove it. But they had a crucial request: He must play his acoustic guitar during the surgery. The musician, Musa Manzini, a jazz bassist, was awake when the doctors performed the surgery last week, and video footage from the local media site News24 shows him strumming an acoustic guitar slowly as they operated. The technique, known as “awake craniotomy,” allows doctors to operate on delicate areas of the brain — like the right frontal lobe, the site of Mr. Manzini’s tumor — without causing damage. Presumably, had he hit a wrong note, it would have been an immediate signal for the surgeons to probe elsewhere. “It can be very difficult to tell the difference between the tumor and normal brain tissue,” said Dr. Basil Enicker, a specialist neurosurgeon who led the operation at Inkosi Albert Luthuli Central Hospital, in the coastal city of Durban. “Once you’re near a critical area, you can pick it up early, because he will tell you.” The surgery is not unusual. The first craniotomies date to prehistoric times, with fossil records showing that patients had holes drilled in their skulls — and survived — as early as 8,000 years ago. In the 1930s, the Canadian-American neurosurgeon Wilder Penfield pioneered modern craniotomies, which he used to treat epilepsy. The procedure has become fairly common globally since then, posing no greater technical challenge than regular brain surgery, Dr. Enicker said. But choosing patients is very important: People who cough, for example, or who cannot lie still for extended periods, are far more dangerous to operate on. © 2018 The New York Times Company

Keyword: Brain imaging; Epilepsy
Link ID: 25815 - Posted: 12.22.2018

It started when Andi Dreher was only three years old. Her head slumped over, her face went blank. It was the first of many epileptic seizures that the Ontario child would endure. At the beginning, Andi would have a couple of seizures a year, but the condition slowly progressed. By the time she turned seven, she was having up to 150 seizures a day. Her family has come to call them "glitches." "The other day at school, she had 27 glitches in less than an hour," said her mom, Lori Dreher. The seizures make it difficult for Andi to do even the simplest tasks, such as walking, talking and eating. "She knows she used to play soccer and she used to do cheerleading — that she used to do these things and now she can't. That's hard." her mom said. 'We're guinea pigs': Canada's oversight process for implanted medical devices stuns suffering patients Among serious neurological conditions in children, epilepsy is the most common. For most, the condition can be controlled by medications. "But about one-third of children who have epilepsy don't respond to medication. A subset of them can potentially be helped by a variety of surgical treatment," said Dr. George Ibrahim, the pediatric neurosurgeon at the Hospital for Sick Children who operated on Andi. Dr. George Ibrahim, pediatric neurosurgeon at the Hospital for Sick Children, examines an image of Andi's brain. (Kelda Yuen/ CBC) When Andi and her family came from Kitchener to meet him last year, Ibrahim said he was struck by the severity of her case. "Her brain is developed in a very unique way," he said. ©2018 CBC/Radio-Canada

Keyword: Epilepsy
Link ID: 25784 - Posted: 12.13.2018

Ashley P. Taylor Electrically stimulating the lateral orbitofrontal cortex, a brain area behind the eyes, improves the moods of people with depression, according to a study published yesterday (November 29) in Current Biology. The technique used by the researchers, led by Edward Chang of the University of California, San Francisco, is called deep brain stimulation (DBS), in which surgically implanted electrodes send electrical pulses to particular areas of the brain. The approach is already in use as a treatment for movement disorders such as Parkinson’s disease and tremors. But results on its ability to treat depression have been mixed, as NPR reports. The researchers worked with 25 epilepsy patients who already had electrodes implanted into their brains as part of their treatments. Many of the study participants also had signs of depression as evaluated by mood tests the researchers administered, Science News reports. The investigators tried stimulating many areas of the brain, and they found that jolts to the lateral orbitofrontal cortex made patients with signs of depression—but not others who didn’t have symptoms—feel better right away. “Wow, I feel a lot better. . . . What did you guys do?” study coauthor Kristin Sellers recalls a patient exclaiming after receiving the stimulation, she tells NPR. “Only the people who had symptoms [of depression] to start with improved their mood, which suggests that perhaps the effect of what we’re doing is to normalize activity that starts off abnormal,” adds another coauthor, Vikram Rao.

Keyword: Depression
Link ID: 25742 - Posted: 12.03.2018

Jon Hamilton There's new evidence that mild pulses of electricity can relieve depression — if they reach the right target in the brain. A study of 25 people with epilepsy found that those who had symptoms of depression felt better almost immediately when doctors electrically stimulated an area of the brain just above the eyes, a team reported Thursday in the journal Current Biology. These people were in the hospital awaiting surgery and had wires inserted into their brains to help doctors locate the source of their seizures. Several of the patients talked about the change they felt when the stimulation of the lateral orbitofrontal cortex began, says Kristin Sellers, an author of the paper and a postdoctoral researcher at the University of California, San Francisco. One person's response was: "Wow, I feel a lot better. ... What did you guys do?" The stimulation only lasted a few minutes. After it stopped, the effect on mood quickly faded. To be sure that the effect was real, the researchers also pretended to stimulate the lateral OFC in the same patients without actually running current through the tiny wires implanted in their brains. In those sham treatments, there was no discernible change. DBS is an approved treatment for tremors, including those associated with Parkinson's disease. But results with depression have been less consistent, and DBS isn't approved for this purpose by the Food and Drug Administration. © 2018 npr

Keyword: Depression
Link ID: 25735 - Posted: 11.30.2018

By R. Douglas Fields SAN DIEGO—In the textbook explanation for how information is encoded in the brain, neurons fire a rapid burst of electrical signals in response to inputs from the senses or other stimulation. The brain responds to a light turning on in a dark room with the short bursts of nerve impulses, called spikes. Each close grouping of spikes can be compared to a digital bit, the binary off-or-on code used by computers. Neuroscientists have long known, though, about other forms of electrical activity present in the brain. In particular, rhythmic voltage fluctuations in and around neurons—oscillations that occur at the same 60-cycle-per-second frequency as AC current in the U.S.—have caught the field’s attention. These gamma waves encode information by changing a signal’s amplitude, frequency or phase (relative position of one wave to another)—and the rhythmic voltage surges influence the timing of spikes. Heated debate has arisen in recent years as to whether these analog signals, akin to the ones used to broadcast AM or FM radio, may play a role in sorting, filtering and organizing the information flows required for cognitive processes. They may be instrumental in perceiving sensory inputs, focusing attention, making and recalling memories and coupling various cognitive processes into one coherent scene. It is thought that populations of neurons that oscillate at gamma frequencies may unite the neural activity in the same way the violin section of an orchestra is coupled together in time and rhythm with the percussion section to create symphonic music. When gamma waves oscillate in resonance, “you get very rich repertoires of behaviors,” says Wolf Singer, a neuroscientist at the Ernst Strüngmann Institute in Frankfurt, Germany, who researches gamma waves. Just as your car’s dashboard will vibrate in sync with the motor vibrating at a resonant frequency, so too can separate populations of neurons couple in resonance. © 2018 Scientific American

Keyword: Brain imaging
Link ID: 25731 - Posted: 11.29.2018

Jef Akst After publishing a 2014 study showing that noninvasive magnetic stimulation of the brain boosted people’s ability to remember an association between two items, Northwestern University neuroscientist Joel Voss began fielding a lot of questions from patients and their families. “We’re of course guarded in the publication talking about what we found—small but reliable increases in memory ability,” he says (Science, 345:1054–57). But some of the news coverage of that paper alluded to the procedure’s potential to treat Alzheimer’s disease and other memory-related disorders. “I got calls—at least two a day for quite a long period of time—and emails: ‘My loved one is suffering from X, Y, or Z; thank God now you can cure it. How do we get to your lab?’” Voss says. He would have to explain to them that this was a scientific study, not an approved treatment. “There are a million steps between here and there, and maybe it would never work—we don’t really know.” But Voss’s team continues to connect those dots, in hopes that one day the technique—the use of magnetic fields to influence activity in neurons close to the brain’s surface—could help patients with any number of brain disorders, and perhaps cognitively healthy people as well. In August, the researchers reported that transcranial magnetic stimulation (TMS) could moderately improve episodic memory—the ability to remember people, events, and other things you’ve encountered in your life (as opposed to, say, how to do something)—when targeted at the correct part of the brain. Voss and his colleagues were interested in activating the hippocampus, a structure near the brain’s center that serves as a hub of memory production and storage. Because the hippocampus itself is inaccessible by TMS—the magnetic field falls off precipitously with depth, explains Voss—the researchers instead targeted areas of the brain where activity correlated with activity in the hippocampus, to try to activate the networks that link more-superficial regions with the deep-brain structure. © 1986 - 2018 The Scientist

Keyword: Learning & Memory
Link ID: 25722 - Posted: 11.27.2018

At 35, Sharon Jakab knew something was wrong when she started hallucinating. "I saw my grandmother on the wall in the room. She was talking to me. I wasn't sleeping, and I was a mess," she says from her home in Burlington, Ont. Jakab had been suffering from postpartum depression following the birth of her daughter. About a year and a half later, Jakab had another episode of postpartum depression following an ectopic pregnancy. It became so bad, she was suicidal. "There was a gun in the house and there were cartridges. I was all set to kill myself." She had to suicide-proof her home by taking away all dangerous objects, even skates, which have sharp blades. Now 61, Jakab has been in and out of hospitals, dealing with what she calls "waves of depression" that have lasted most of her adult life. She's tried about a dozen medications, including the antipsychotic drug clozapine. "Clozapine really helped me a lot, but I still suffered from depression, psychosis and mania." Because standard treatment like medication and therapy weren't effective, Jakab was diagnosed with treatment-resistant depression, a severe form of depression that close to a million Canadians experience. Electroconvulsive therapy or ECT, better known as shock treatment, is still considered the go-to treatment but comes with the common side effect of memory loss. So doctors are now exploring less invasive experimental approaches like brain stimulation that rewires the brain's circuits. ©2018 CBC/Radio-Canada

Keyword: Depression
Link ID: 25718 - Posted: 11.26.2018

Sara Reardon ‘Mini brains’ grown in a dish have spontaneously produced human-like brain waves for the first time — and the electrical patterns look similar to those seen in premature babies. The advancement could help scientists to study early brain development. Research in this area has been slow, partly because it is difficult to obtain fetal-tissue samples for analysis and nearly impossible to examine a fetus in utero. Many researchers are excited about the promise of these ‘organoids’, which, when grown as 3D cultures, can develop some of the complex structures seen in brains. But the technology also raises questions about the ethics of creating miniature organs that could develop consciousness. A team of researchers led by neuroscientist Alysson Muotri of the University of California, San Diego, coaxed human stem cells to form tissue from the cortex — a brain region that controls cognition and interprets sensory information. They grew hundreds of brain organoids in culture for 10 months, and tested individual cells to confirm that they expressed the same collection of genes seen in typical developing human brains1. The group presented the work at the Society for Neuroscience meeting in San Diego this month. Muotri and his colleagues continuously recorded electrical patterns, or electroencephalogram (EEG) activity, across the surface of the mini brains. By six months, the organoids were firing at a higher rate than other brain organoids previously created, which surprised the team. © 2018 Springer Nature Limited.

Keyword: Development of the Brain; Epilepsy
Link ID: 25694 - Posted: 11.16.2018