Tag Archive: Brain


Illustration of an astrocyte

Everything we do — all of our movements, thoughts and feelings – are the result of neurons talking with one another, and recent studies have suggested that some of the conversations might not be all that private. Brain cells known as astrocytes may be listening in on, or even participating in, some of those discussions. But a new mouse study suggests that astrocytes might only be tuning in part of the time — specifically, when the neurons get really excited about something. This research, published in Neuron, was supported by the National Institute of Neurological Disorders and Stroke (NINDS), part of the National Institutes of Health.

For a long time, researchers thought that the star-shaped astrocytes (the name comes from the Greek word for star) were simply support cells for the neurons.

It turns out that these cells have a number of important jobs, including providing nutrients and signaling molecules to neurons, regulating blood flow, and removing brain chemicals called neurotransmitters from the synapse. The synapse is the point of information transfer between two neurons. At this connection point, neurotransmitters are released from one neuron to affect the electrical properties of the other. Long arms of astrocytes are located next to synapses, where they can keep tabs on the conversations going on between neurons.

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If you thought the post on twins sharing consciousness was awesome, wait until you hear this.

A 44-year-old French man one day went to the trip to the doctor’s because he felt a pain in his left leg. He’s a married man with two kids and a steady job. Doctor’s found that he had hydrocephalus as a child (when your brain is filled with fluids) so they decided to run some brain scans.

What they found was that the majority of his head was filled with fluid. Over time, the buildup caused his lateral ventricles to swell so much that his brain had been flattened to a thin sheet. Doctors estimated that his brain mass had been reduced by at most 70%, affecting the areas in charge of motion, language, emotion, and, well, everything.

Shockingly, he was fine. While his IQ was only 75, he wasn’t mentally challenged. He held a steady job, raised a family, and didn’t have trouble interacting with others. Over time, his brain had adapted to all that pressure, and even though he had fewer neurons that most, Jacques was still a fully functional human being. The doctors drained the fluid and while his brain is much smaller now, he is still a healthy individual with a normal life.

3D Brain Visualizations Let People Watch Their Neurons Firing In Real-Time [Video]

Philip Rosedale, creator of Second Life, and Adam Gazzaley, a neuroscientist at the University of California San Francisco, have created a way for you to see each thought as it flies through your mind. The Glass Brain project was on display at SXSW, and gave visitors a chance to see how their brains react to different stimuli.

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Scientists unlock mystery of out-of-body experiences (aka astral trips)

Some people claim that they have experienced out-of-body experiences—aka “astral trips”—floating outside of their bodies and watching themselves from the outside. A team of scientists found someone who says she can do this at will and put her into a brain scanner. What they discovered was surprisingly strange.

Andra M. Smith and Claude Messierwere from the University of Ottawa described this subject’s ability in their paper, published in Frontiers of Human Neuroscience:

She was able to see herself rotating in the air above her body, lying flat, and rolling along with the horizontal plane. She reported sometimes watching herself move from above but remained aware of her unmoving “real” body. The participant reported no particular emotions linked to the experience.

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Why does the brain remember dreams?

Some people recall a dream every morning, whereas others rarely recall one. A team led by Perrine Ruby, an Inserm Research Fellow at the Lyon Neuroscience Research Center, has studied the brain activity of these two types of dreamers in order to understand the differences between them. In a study published in the journal Neuropsychopharmacology, the researchers show that the temporo-parietal junction, an information-processing hub in the brain, is more active in high dream recallers. Increased activity in this brain region might facilitate attention orienting toward external stimuli and promote intrasleep wakefulness, thereby facilitating the encoding of dreams in memory.

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The reason for dreaming is still a mystery for the researchers who study the difference between “high dream recallers,” who recall dreams regularly, and “low dream recallers,” who recall dreams rarely. In January 2013, the team led by Perrine Ruby, Inserm researcher at the Lyon Neuroscience Research Center, made the following two observations: “high dream recallers” have twice as many time of wakefulness during sleep as “low dream recallers” and their brains are more reactive to auditory stimuli during sleep and wakefulness. This increased brain reactivity may promote awakenings during the night, and may thus facilitate memorisation of dreams during brief periods of wakefulness.

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The Alpha IMS retinal prosthesis, implanted in a human patient

DARPA, at the behest of the US Department of Defense, is developing a black box brain implant — an implant that will be wired into a soldier’s brain and record their memories. If the soldier then suffers memory loss due to brain injury, the implant will then be used to restore those memories. The same implant could also be used during training or in the line of duty, too — as we’ve reported on in the past, stimulating the right regions of the brain can improve how quickly you learn new skills, reduce your reaction times, and more.

The project, which DARPA has wittily named Restoring Active Memory, is currently at the stage where it’s seeking proposals from commercial companies that have previously had success with brain implants, such as Medtronic. As yet, we don’t know who has submitted proposals to DARPA, but it’ll probably be the usual suspects. Medtronic, which creates deep-brain simulation (DBS) implants that are almost miraculous in their ability to control the debilitating effects of Parkinson’s disease (video embedded below), is surely interested. Brown University, which famously created a brain-computer interface that is implanted into the brain and communicates wirelessly with a nearby computer, must be a contender. Companies with big R&D budgets, like IBM and GE, might be involved as well.

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New research suggests children have a strong sense they existed before they were conceived.

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We’ve all ruminated about the possibility of life after death. But what about the notion of life before birth—or even conception?

While Christian theology denies such a thing is possible, the concept that life precedes physical fertilization is a given for people who believe in reincarnation. But is such an idea learned? Or is it based on an innate feeling about our own immortality?

Newly published research that analyzes answers given by two groups of children—one urban, one rural—suggests the latter. It finds youngsters intuitively believe that their own existence, at least in the form of feelings and wants, pre-dated their conception.

“Even kids who had biological knowledge about reproduction still seemed to think that they had existed in some sort of eternal form,” lead author Natalie Emmons, a postdoctoral fellow in psychology at Boston University, told the institution’s news service. “And that form really seemed to be about emotions and desires.”

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A review and update of a controversial 20-year-old theory of consciousness published in Physics of Life Reviews claims that consciousness derives from deeper level, finer scale activities inside brain neurons. The recent discovery of quantum vibrations in “microtubules” inside brain neurons corroborates this theory, according to review authors Stuart Hameroff and Sir Roger Penrose. They suggest that EEG rhythms (brain waves) also derive from deeper level microtubule vibrations, and that from a practical standpoint, treating brain microtubule vibrations could benefit a host of mental, neurological, and cognitive conditions.

The theory, called “orchestrated objective reduction” (‘Orch OR’), was first put forward in the mid-1990s by eminent mathematical physicist Sir Roger Penrose, FRS, Mathematical Institute and Wadham College, University of Oxford, and prominent anesthesiologist Stuart Hameroff, MD, Anesthesiology, Psychology and Center for Consciousness Studies, The University of Arizona, Tucson. They suggested that quantum vibrational computations in microtubules were “orchestrated” (“Orch”) by synaptic inputs and memory stored in microtubules, and terminated by Penrose “objective reduction” (‘OR’), hence “Orch OR.” Microtubules are major components of the cell structural skeleton.

Orch OR was harshly criticized from its inception, as the brain was considered too “warm, wet, and noisy” for seemingly delicate quantum processes.. However, evidence has now shown warm quantum coherence in plant photosynthesis, bird brain navigation, our sense of smell, and brain microtubules. The recent discovery of warm temperature quantum vibrations in microtubules inside brain neurons by the research group led by Anirban Bandyopadhyay, PhD, at the National Institute of Material Sciences in Tsukuba, Japan (and now at MIT), corroborates the pair’s theory and suggests that EEG rhythms also derive from deeper level microtubule vibrations. In addition, work from the laboratory of Roderick G. Eckenhoff, MD, at the University of Pennsylvania, suggests that anesthesia, which selectively erases consciousness while sparing non-conscious brain activities, acts via microtubules in brain neurons.

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Supercomputer takes 40 mins to calculate a single second of human brain activity

One of the world’s largest supercomputers has accurately mapped one second’s worth of activity in a human brain, in what researchers claim is the most accurate simulation to date.

Scientists in Japan simulated one per cent of the neuronal network in the brain using the K computer, the fourth most powerful supercomputer in the world.

With 705,024 processor cores and 1.4 million GB of RAM at its disposal, the K computer took 40 minutes to model the data in a project designed to test the ability of the supercomputer and gauge the limits of brain simulation.

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A new study suggests the existence of a state of mind called dysanaesthesia, which is neither consciousness nor unconsciousness.

Man in a coma

With anesthetics properly given, very few patients wake up during surgery. However, new findings point to the possibility of a state of mind in which a patient is neither fully conscious nor unconscious, experts say.
This possible third state of consciousness, may be a state in which patients can respond to a command, but are not disturbed by pain or the surgery, according to Dr. Jaideep Pandit, anesthetist at St John’s College in England.
Pandit dubbed this state dysanaesthesia, and said the evidence that it exists comes partly from a recent study, in which 34 surgical patients were anesthetized, and had their whole body paralyzed except for their forearm, allowing them to move their fingers in response to commands or to signify if they are awake or in pain during surgery.

Can inhaled stem cells fix your brain?

In certain neurosurgical procedures, like fixing pituitary glands, surgeons can remove a tumor through the nose with minimal damage to surrounding tissue. It turns out, that passing things in the other direction—into the brain through an intranasal route—has many advantages too. Everything from drugs, proteins, and gene vectors, to stem cells, can now by administered in this way. The major question for today, is not so much what do these agents do, but where do they go once they are inside? StemGenex, a La Jolla-based company, has recently announced their new hopes for a treatment which could potentially address several neurological diseases. They are now offering a therapy for patients with multiple sclerosis in based on the intranasal delivery of mesenchymal stem cells.

The preferred medical term for act of snorting is insufflation. While insufflation is an obvious choice to deliver drugs to the sinuses or lungs, it is now appreciated that many bioactive agents can get much further than that. One major advantage of this method is the low barrier of entry through the mucous membranes into the bloodstream. Although some pro-drugs, like codeine, require absorption through the gut to pass to the liver where they can be metabolized into an active form, many other drugs are compromised by a digestive passage. What’s more important though here for the brain, is that the normally-intact blood brain barrier can by bypassed either by slipping around the perineural sheath cells, or getting endocytosed and retrogradely transported along either the olfactory nerves, or the trigeminal nerves.

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Your Brain Sees Things You Don’t

A new study by UA doctoral student Jay Sanguinetti indicates that our brains perceive objects in everyday life of which we may never be aware. The finding challenges currently accepted models about how the brain processes visual information.

A look inside the mind: Davi Vitela dons a cap used to take EEG scans of her brain activity while she views a series of images. Jay Sanguinetti's study indicates that our minds perceive objects in everyday life of which we are never consciously aware. (Photo by Patrick McArdle/UANews)

University of Arizona doctoral degree candidate Jay Sanguinetti has authored a new study, published online in the journal Psychological Science, that indicates that the brain processes and understands visusal input that we may never consciously perceive.

The finding challenges currently accepted models about how the brain processes visual information.

A doctoral candidate in the UA’s Department of Psychology in the College of Science, Sanguinetti showed study participants a series of black silhouettes, some of which contained meaningful, real-world objects hidden in the white spaces on the outsides.

Saguinetti worked with his adviser Mary Peterson, a professor of psychology and director of the UA’s Cognitive Science Program, and with John Allen, a UA Distinguished Professor of psychology, cognitive science and neuroscience, to monitor subjects’ brainwaves with an electroencephalogram, or EEG, while they viewed the objects.

“We were asking the question of whether the brain was processing the meaning of the objects that are on the outside of these silhouettes,” Sanguinetti said. “The specific question was, ‘Does the brain process those hidden shapes to the level of meaning, even when the subject doesn’t consciously see them?”

The answer, Sanguinetti’s data indicates, is yes.

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Researchers at the University of Colorado Boulder have demonstrated that our brains could process new situations by relying on a method similar to the “pointer” system used by computers.

Pointers are used to tell a computer where to look for information stored elsewhere in the system.

For the study, the research team relied on sentences with words used in unique ways to test the brain’s ability to understand the role familiar words play in a sentence even when those words are used in unfamiliar, and even nonsensical, ways.

For example, in the sentence, “I want to desk you,” we understand the word “desk” is being used as a verb even though our past experience with the word “desk” is as a noun.

“The fact that you understand that the sentence is grammatically well formed means you can process these completely novel inputs,” said Randall O’Reilly, a professor in CU-Boulder’s Department of Psychology and Neuroscience and co-author of the study.

This shows that human brains are able to understand the sentence as a structure with variables — a subject, a verb and often, an object — and that the brain can assign a wide variety of words to those variables and still understand the sentence structure.

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In 2005, artist Jennifer Kanary’s sister-in-law committed suicide while suffering from a psychotic episode. This event led Kanary to develop Labyrinth Psychotica, an experience designed to give people more insight into how it feels to suffer through psychosis.

Users are strapped into virtual reality gear and transported into the mind of a psychotic girl named Jamie. The whole experience lasts twelve minutes, during which ‘normal’ reality gets increasingly intertwined with Jamie’s psychotic reality, making it more and more difficult to distinguish between what’s real and what’s not.

With Labyrinth Psychotica, Kanary wants to provide family members and mental healthcare workers with means to better understand what someone in a psychotic state goes through. She hopes this will lead to more understanding and better treatments.

According to a new study published in the journal Psychological Science, the width of blood vessels in the retina – a light-sensitive layer at the back of the eye – may indicate brain health.

A schematic section through the human eye with a schematic enlargement of the retina (University of Utah)

A schematic section through the human eye with a schematic enlargement of the retina (University of Utah)

Previous studies showed that younger people who score low on intelligence tests, such as IQ, tend to be at higher risk for poorer health and shorter lifespan.

In the current study, psychological scientists led by Dr Idan Shalev of Duke University wondered whether intelligence might serve as a marker indicating the health of the brain, and specifically the health of the system of blood vessels that provides oxygen and nutrients to the brain.

To investigate the potential link between intelligence and brain health, they borrowed a technology from a somewhat unexpected domain – ophthalmology.

The team used digital retinal imaging to gain a window onto vascular conditions in the brain by looking at the small blood vessels of the retina. Retinal blood vessels share similar size, structure, and function with blood vessels in the brain and can provide a way of examining brain health in living humans.

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These tiny cages, each 100 microns long and 40 microns wide, may not look like much, but they are the new semi-trucks of targeted medicine delivery. Developed by a team of Chinese researchers, in conjunction with Swiss and South Korean institutes, the nickel-coated microbots are steered wirelessly by electromagnetic fields. Thanks to that external control, these microbots can carry precious cargo to exactly where the body needs it, in especially to sensitive places like brains or eyes.

Tiny robots swimming through blood for medical purposes are a relatively new phenomena. In 2011, researchers published a paper on miniscule motors that could propel such machines. Other microbots can carry medicine, but their spiral shape and smaller bodies limit how much can carry. Magnetically steered robots inside living animals have also been tested before.

What makes these microbots unique? Size! Zhang Li, a researcher on the project, explains that “a microbot is like a vehicle that ships drugs directly to the affected area. And I want to design a truck, not a car.” Larger robots mean more medicine delivered. Human trials of these robots are likely decades away, but the robots have been tested in rabbits and mice.

Image: Zac Vawter walks with the help of a bionic leg.

After losing his lower right leg in a motorcycle accident four-and-a-half years ago, 32-year-old Zac Vawter has been fitted with an artificial limb that uses neurosignals from his upper leg muscles to control the prosthetic knee and ankle. The motorized limb is the first thought-controlled bionic leg, scientists at the Rehabilitation Institute of Chicago reported Wednesday in The New England Journal of Medicine.

“This is a groundbreaking development,” says lead author Levi Hargrove, a biomedical engineer and research scientist at RIC. “It allows people to seamlessly transition between walking along level ground and going up and down stairs and slopes.”

In this Oct. 25, 2012 photo, Zac Vawter, fitted with an experimental "bionic" leg, is silhouetted on the Ledge at the Willis Tower in Chicago. Vawter ...

Until now, only thought-controlled bionic arms have been available to amputees.

When Vawter thinks he wants to move his leg, the brain signal travels down his spinal cord and through peripheral nerves and is picked up by electrodes in the bionic leg. Unlike robotic models currently on the market, the prosthesis allows a normal, smooth gait no matter the incline. Although the cost hasn’t been determined, a version could be available to the more than one million Americans with leg amputations within three to five years, the Chicago scientists said.

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People can be easily tricked into believing an artificial finger is their own, shows a study published in The Journal of Physiology. The results reveal that the brain does not require multiple signals to build a picture body ownership, as this is the first time the illusion has been created using sensory inputs from the muscle alone.

The discovery provides new insight into clinical conditions where body representation in the brain is disrupted due to changes in the central or peripheral nervous systems e.g. stroke, schizophrenia and phantom limb syndrome following amputation.

Professor Simon Gandevia, Deputy Director of Neuroscience Research Australia (NeuRA), says: “It may seem silly to ask yourself whether your index finger is part of your body. However, our current findings demonstrate that this question has led to important insights into key brain functions.

“These findings could lead to new clinical interventions where the addition or the removal of specific sensory stimuli is used to change someone’s body image.”

In the experiment, subjects held an artificial finger with their left hand that was located 12 cm above their right index finger. Vision was eliminated and anaesthesia was used to numb the skin and remove feelings of joint movement. When the artificial finger and the right index finger were moved synchronously, subjects reported they were holding their own index finger: the brain incorrectly incorporated the artificial finger into its internal body representation.

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Researchers from the University of Montreal and their colleagues have found brain activity beyond a flat line EEG, which they have called Nu-complexes (from the Greek letter n). According to existing scientific data, researchers and doctors had established that beyond the so-called “flat line” (flat electroencephalogram or EEG), there is nothing at all, no brain activity, no possibility of life. This major discovery suggests that there is a whole new frontier in animal and human brain functioning.

The researchers observed a human patient in an extreme deep hypoxic coma under powerful anti-epileptic medication that he had been required to take due to his health issues. “Dr. Bogdan Florea from Romania contacted our research team because he had observed unexplainable phenomena on the EEG of a coma patient. We realized that there was cerebral activity, unknown until now, in the patient’s brain,” says Dr. Florin Amzica, director of the study and professor at the University of Montreal’s School of Dentistry.

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Philosophers and scientists have long puzzled over where human imagination comes from. In other words, what makes humans able to create art, invent tools, think scientifically and perform other incredibly diverse behaviors?

The answer, Dartmouth researchers conclude in a new study, lies in a widespread neural network — the brain’s “mental workspace” — that consciously manipulates images, symbols, ideas and theories and gives humans the laser-like mental focus needed to solve complex problems and come up with new ideas.

Their findings, titled “Network structure and dynamics of the mental workspace,” appear in the Proceedings of the National Academy of Sciences.

“Our findings move us closer to understanding how the organization of our brains sets us apart from other species and provides such a rich internal playground for us to think freely and creatively,” says lead author Alex Schlegel , a graduate student in the Department of Psychological and Brain Sciences. “Understanding these differences will give us insight into where human creativity comes from and possibly allow us to recreate those same creative processes in machines.”

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