The Future is NOW: Training Pilots Through the use of Electroneural Stimulation

Transcranial Direct Current Stimulation Modulates Neuronal Activity and Learning in Pilot Training

Authors:

Choe et al

Abstract:

Skill acquisition requires distributed learning both within (online) and across (offline) days to consolidate experiences into newly learned abilities. In particular, piloting an aircraft requires skills developed from extensive training and practice. Here, we tested the hypothesis that transcranial direct current stimulation (tDCS) can modulate neuronal function to improve skill learning and performance during flight simulator training of aircraft landing procedures. Thirty-two right-handed participants consented to participate in four consecutive daily sessions of flight simulation training and received sham or anodal high-definition-tDCS to the right dorsolateral prefrontal cortex (DLPFC) or left motor cortex (M1) in a randomized, double-blind experiment. Continuous electroencephalography (EEG) and functional near infrared spectroscopy (fNIRS) were collected during flight simulation, n-back working memory, and resting-state assessments. tDCS of the right DLPFC increased midline-frontal theta-band activity in flight and n-back working memory training, confirming tDCS-related modulation of brain processes involved in executive function. This modulation corresponded to a significantly different online and offline learning rates for working memory accuracy and decreased inter-subject behavioral variability in flight and n-back tasks in the DLPFC stimulation group. Additionally, tDCS of left M1 increased parietal alpha power during flight tasks and tDCS to the right DLPFC increased midline frontal theta-band power during n-back and flight tasks. These results demonstrate a modulation of group variance in skill acquisition through an increasing in learned skill consistency in cognitive and real-world tasks with tDCS. Further, tDCS performance improvements corresponded to changes in electrophysiological and blood-oxygenation activity of the DLPFC and motor cortices, providing a stronger link between modulated neuronal function and behavior.

pop sci write up.

This is my reaction.

Human Brains may Have Been Selected for Flexibility by Evolution

Human brains exhibit more plasticity, the tendency to be modeled by the environment, than chimpanzee brains, which may account for part of human evolution, according to researchers at Georgia State University, the George Washington University and The University of Texas MD Anderson Cancer Center.

The findings provide insight into why humans are capable of adapting to various environments and cultures. The study, the first of its kind to examine the inherited genetic factors of brain organization in humans compared to their closest living relatives, was published Nov. 16 in the journal Proceedings of the National Academy of Sciences.

The research team studied 218 human brains and 206 chimpanzee brains to compare two things: brain size and organization as related to genetic similarity. The study found that human and chimpanzee brain size were both greatly influenced by genetics.

In contrast, the findings related to brain organization revealed key differences between chimpanzees and humans. In chimpanzees, brain organization is also highly inherited, but in humans this is not the case.

"We found that the anatomy of the chimpanzee brain is more strongly controlled by genes than that of human brains, suggesting the human brain is extensively shaped by its environment no matter its genetics," said Aida Gómez-Robles, postdoctoral scientist at the George Washington University Center for the Advanced Study of Human Paleobiology and lead author on the paper.

These findings could also have important implications regarding human susceptibility to degenerative diseases.

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paper link.

Injectable Brain Implants Developed

A simple injection is now all it takes to wire up a brain. A diverse team of physicists, neuroscientists and chemists has implanted mouse brains with a rolled-up, silky mesh studded with tiny electronic devices, and shown that it unfurls to spy on and stimulate individual neurons.

The implant has the potential to unravel the workings of the mammalian brain in unprecedented detail. “I think it’s great, a very creative new approach to the problem of recording from large number of neurons in the brain,” says Rafael Yuste, director of the Neuro­technology Center at Columbia University in New York, who was not involved in the work.

If eventually shown to be safe, the soft mesh might even be used in humans to treat conditions such as Parkinson’s disease, says Charles Lieber, a chemist at Harvard University on Cambridge, Massachusetts, who led the team.

link.

paper link.

Fructose & Glucose Effect Appetite Differently

Differential effects of fructose versus glucose on brain and appetitive responses to food cues and decisions for food rewards

Authors:

Luo et al

Abstract:

Prior studies suggest that fructose compared with glucose may be a weaker suppressor of appetite, and neuroimaging research shows that food cues trigger greater brain reward responses in a fasted relative to a fed state. We sought to determine the effects of ingesting fructose versus glucose on brain, hormone, and appetitive responses to food cues and food-approach behavior. Twenty-four healthy volunteers underwent two functional magnetic resonance imaging (fMRI) sessions with ingestion of either fructose or glucose in a double-blinded, random-order cross-over design. fMRI was performed while participants viewed images of high-calorie foods and nonfood items using a block design. After each block, participants rated hunger and desire for food. Participants also performed a decision task in which they chose between immediate food rewards and delayed monetary bonuses. Hormones were measured at baseline and 30 and 60 min after drink ingestion. Ingestion of fructose relative to glucose resulted in smaller increases in plasma insulin levels and greater brain reactivity to food cues in the visual cortex (in whole-brain analysis) and left orbital frontal cortex (in region-of-interest analysis). Parallel to the neuroimaging findings, fructose versus glucose led to greater hunger and desire for food and a greater willingness to give up long-term monetary rewards to obtain immediate high-calorie foods. These findings suggest that ingestion of fructose relative to glucose results in greater activation of brain regions involved in attention and reward processing and may promote feeding behavior.

Autism and a Ted Talk

Cute Trick: a DIY Demo of Electrophysiology

Autism-associated Mutation Shown to Have Strong, Negative Effects on Synapses

Autism-associated mutation inhibits protein kinase C-mediated neuroligin-4X enhancement of excitatory synapses

Authors:

Bemben et al

Abstract:

Autism spectrum disorders (ASDs) comprise a highly heritable, multifarious group of neurodevelopmental disorders, which are characterized by repetitive behaviors and impairments in social interactions. Point mutations have been identified in X-linked Neuroligin (NLGN) 3 and 4X genes in patients with ASDs and all of these reside in their extracellular domains except for a single point mutation in the cytoplasmic domain of NLGN4X in which an arginine is mutated to a cysteine (R704C). Here we show that endogenous NLGN4X is robustly phosphorylated by protein kinase C (PKC) at T707, and R704C completely eliminates T707 phosphorylation. Endogenous NLGN4X is intensely phosphorylated on T707 upon PKC stimulation in human neurons. Furthermore, a phospho-mimetic mutation at T707 has a profound effect on NLGN4X-mediated excitatory potentiation. Our results now establish an important interplay between a genetic mutation, a key posttranslational modification, and robust synaptic changes, which can provide insights into the synaptic dysfunction of ASDs.

Steps to Brain Upgrade Implants

In a study in the journal Neuron, scientists describe a new high data-rate, low-power wireless brain sensor. The technology is designed to enable neuroscience research that cannot be accomplished with current sensors that tether subjects with cabled connections.

Experiments in the paper confirm that new capability. The results show that the technology transmitted rich, neuroscientifically meaningful signals from animal models as they slept and woke or exercised.

"We view this as a platform device for tapping into the richness of electrical signals from the brain among animal models where their neural circuit activity reflects entirely volitional and naturalistic behavior, not constrained to particular space," said Arto Nurmikko, professor of engineering affiliated with the Brown Institute for Brain Science and the paper's senior and corresponding author. "This enables new types of neuroscience experiments with vast amounts of brain data wirelessly and continuously streamed from brain microcircuits."

The custom-engineered neuroelectronic platform is composed of two elements: a 100-channel transmitter only 5 centimeters in its largest dimension and weighing only 46.1 grams, and a four-antenna receiver that looks like a home Wi-Fi router but employs sophisticated signal processing to maximize the transmitter's signal while the subject is moving around. Via a small port embedded in a subject's skull, the transmitter connects to a tiny implanted electrode array that detects the activity of scores of neurons in the cortex. The wireless transmitter is compatible with multiple types and classes of brain sensors, Nurmikko said, with a view toward future sensor development

link.

An Intriguing Brain Protein Unique to Humans

A protein that may partly explain why human brains are larger than those of other animals has been identified by scientists from two stem-cell labs at UC San Francisco, in research published in the November 13, 2014 issue of Nature.

Key experiments by the UCSF researchers revealed that the protein, called PDGFD, is made in growing brains of humans, but not in mice, and appears necessary for normal proliferation of human brain stem cells growing in a lab dish.

The scientists made their discovery as part of research in which they identified genes that are activated to make specific proteins in crucial stem cells in the brain known as radial glial cells. The discovery stems from a collaboration between the laboratories of leading radial glial cell scientist Arnold Kriegstein MD, PhD, director of the Eli and Edythe Broad Center of Regeneration Medicine and Stem Cell Research at UCSF, and Michael Oldham, PhD, who recently made a rapid career leap from graduate student to principal investigator and Sandler Fellow at UCSF.

Radial glial cells make the neurons in the growing brain, including the neurons in the cerebral cortex, the seat of higher brain functions. The cerebral cortex varies in size 10,000-fold among mammals. Changes in the timing, location and degree of cell division and nerve cell generation by radial glial cells can dramatically alter the shape and function of the cortex.

The UCSF team discovered that PDGFD is secreted by human radial glial cells and acts on radial glial cells as well as other progenitor cells in the developing brain.

link.

Just How Parallel *IS* the Human Brain?

The human brain is often described as a massively parallel computing machine. That raises an interesting question: just how parallel is it?

Today, we get an answer thanks to the work of Harris Georgiou at the National Kapodistrian University of Athens in Greece, who has counted the number of “CPU cores” at work in the brain as it performs simple tasks in a functional magnetic resonance imaging (fMRI) machine. The answer could help lead to computers that better match the performance of the human brain.

link.

How White Noise and Cars led to Clues About the Human Imagination

Here’s a curious experiment. Take some white noise and use it to produce a set of images that are essentially random arrangements of different coloured blocks. Show these images to a number of people and ask whether any of the images remind them of, say, a car.

Most of the time, these random images will appear to people as, well, random. But every now and again somebody will say that an image does remind them of a car. Set this image aside. And repeat.

After assessing, say, 100,000 images in this way, you’ll end up with a set of essentially random pictures that remind people of cars. Take the average of these and you will find something interesting. The resulting image does indeed look like a blurry car, not a specific kind of car but a very general template of one.

“Although our dataset consists of only white noise, a car emerges,” say Carl Vondrick and pals at the Massachusetts Institute of Technology in Cambridge, who carried out the research.

Today, these guys say that this process extracts the visual template that the human brain uses to distinguish objects such as cars from not-cars. And because this process is based on noise and imagination alone, Vondrick and co say it provides a unique insight into the nature of human imagination.

link.

Claustrum: The *YOU* in Your Brain

ONE moment you're conscious, the next you're not. For the first time, researchers have switched off consciousness by electrically stimulating a single brain area.

Scientists have been probing individual regions of the brain for over a century, exploring their function by zapping them with electricity and temporarily putting them out of action. Despite this, they have never been able to turn off consciousness – until now.

Although only tested in one person, the discovery suggests that a single area – the claustrum – might be integral to combining disparate brain activity into a seamless package of thoughts, sensations and emotions. It takes us a step closer to answering a problem that has confounded scientists and philosophers for millennia – namely how our conscious awareness arises.

link.

New Scientist warning.

I was tempted to call this the seat of the soul, but...

BRAIN Project Proposals are Getting a Reality Check

Neuroscientists were over the moon in April 2013 when President Barack Obama announced a bold new initiative to study the human brain in action. But in their heady excitement, some may have forgotten to check the math in their first proposals. At least, that's the contention of a group of physicists, engineers, and neuroscientists meeting this week in Arlington, Virginia, to discuss which ideas are likely to succeed and which may fall flat.

Key to the success of the roughly $100 million Brain Research through Advancing Innovative Neurotechnologies (BRAIN) Initiative is crafting new tools or methods to measure neural activity either from inside or outside the brain. Unfortunately, some ideas “violated either a physical law or some very significant engineering constraint or biological constraint,” says neurophysicist Partha Mitra of Cold Spring Harbor Laboratory in New York, who helped organize the meeting, sponsored by the National Science Foundation.

The goal is to have a realistic discussion of what the physical limits are, he says, so “scientists who want to make devices will not make crazy proposals,” or, “if a proposal is crazy, one could recognize it as such” and look for other ways to make the idea work.

One such “fanciful” idea is to build nanosized radios that could snuggle up to individual neurons to record and transmit information about their activity, says physicist Peter Littlewood, director of Argonne National Laboratory in Lemont, Illinois. But any radio small enough to be injected into the brain without causing significant harm would not be able to transmit any information out through tissue and bone, he says. Make the devices any more powerful, he adds, and they'd likely cook the surrounding brain. Another aspiration that is likely doomed is to get microscopes that probe the brain with pulses of light to penetrate much further than they already do, Mitra says. A little more than 1 mm is possible, he adds, but even 1 cm is “out of the question, since the signal to background [noise] ratio decreases exponentially with depth.”

But physicists and engineers shouldn't simply shoot down outlandish proposals—or gripe about the intrinsic messiness of the brain's biology. They should model themselves as “fancy technicians” who can help develop revolutionary tools, Littlewood says. There are precedents for such collaboration, he notes: He, Mitra, and their colleagues at Bell Labs, for example, helped develop functional magnetic resonance imaging in the 1990s.

link.

Prepare for the Vampire Baby Boomers!

Something — or some things — in the blood of young mice has the ability to restore mental capabilities in old mice, a new study by Stanford University School of Medicine investigators has found.

If the same goes for humans, it could spell a new paradigm for recharging our aging brains, and it might mean new therapeutic approaches for treating dementias such as Alzheimer's disease.

In the study, to be published online May 4 in Nature Medicine, the researchers used sophisticated techniques to pin down numerous important molecular, neuroanatomical and neurophysiological changes in the brains of old mice that shared the blood of young mice.

But they also conducted a critical experiment that was far from sophisticated, said Tony Wyss-Coray, PhD, the senior author of the study and a professor of neurology and neurological sciences. The scientists simply compared older mice's performance on standard laboratory tests of spatial memory after these mice had received infusions of plasma (the cell-free part of blood) from young versus old mice, or no plasma at all.

"This could have been done 20 years ago," said Wyss-Coray, who is also senior research career scientist at the Veterans Affairs Palo Alto Health Care System. "You don't need to know anything about how the brain works. You just give an old mouse young blood and see if the animal is smarter than before. It's just that nobody did it."

Wyss-Coray has co-founded a biotechnology company, Alkahest, to explore the therapeutic implications of the new study's findings. He serves as the director of Alkahest's scientific advisory board.

The study's lead author, Saul Villeda, PhD, now has an active lab of his own as a faculty fellow in anatomy at the University of California-San Francisco. Villeda was a graduate student at Stanford and, briefly, a postdoctoral scholar under Wyss-Coray's direction when the bulk of the work was performed.

"We've shown that at least some age-related impairments in brain function are reversible. They're not final," Villeda said.

link.

Myelin's a Basal Characteristic of Neurons, More Derved Have Less

Harvard neuroscientists have made a discovery that turns 160 years of neuroanatomy on its head.

Myelin, the electrical insulating material long known to be essential for the fast transmission of impulses along the axons of nerve cells, is not as ubiquitous as thought, according to a new work lead by Professor Paola Arlotta of the Harvard Stem Cell Institute (HSCI) and the University's Department of Stem Cell and Regenerative Biology, in collaboration with Professor Jeff Lichtman, of Harvard's Department of Molecular and Cellular Biology.

"Myelin is a relatively recent invention during evolution," says Arlotta. "It's thought that myelin allowed the brain to communicate really fast to the far reaches of the body, and that it has endowed the brain with the capacity to compute higher level functions." In fact, loss of myelin is a feature of a number of devastating diseases, including multiple sclerosis and schizophrenia.

But the new research shows that despite myelin essential roles in the brain, "some of the most evolved, most complex neurons of the nervous system have less myelin than older, more ancestral ones" Arlotta, co-director of the HSCI neuroscience program, says.

What this means, Arlotta says, is that the higher in the cerebral cortex one looks – the closer to the top of the brain, which is its most evolved region - the less myelin one finds. Not only that, but "neurons in this part of the brain display a brand new way of positioning myelin along their axons that has not been previously seen. They have 'intermittent myelin' with long axon tracts that lack myelin interspersed among myelin-rich segments.

link.

Mouse Brain Mapped

The brain is an incredibly complex organ. The tiny mouse brain, for example, contains over 86 million neurons, each with over 1,000 different connections, clustered in different groupings. In a sense, the neural networks resemble a complex highway system between cities. To navigate the brain, researchers are going to need some maps, and two of the most detailed maps have just been created.

Scientists from the Allen Institute for Brain Science in Seattle pored through massive data sets to build two new maps: one of gene expression in the developing human brain, and another of neural networks in a mouse brain. The maps, which are publicly available, will serve as resources for researchers around the world.

Already, the data are revealing valuable insights about formation of autism and the way mammalian brains process information. Scientists shared their findings in two separate papers published today in the journal Nature.

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