Reuters has a report on how the brain reacts to fear. Subjects were instructed to play a pac-man like game where they tried to evade a predator. When they were caught, subjects received a mild shock. While the subjects were playing the research team was performing brain scans on them to determine how fear affects the brain.

Simultaneous brain scans measuring blood flow showed that when the predator was distant, lower parts of the prefrontal cortex area of the brain behind the eyebrows were active. This region is associated with complex decision-making, such as planning an escape. But when the predator moved closer, activity shifted to the periaqueductal grey area, responsible for quick-response survival mechanisms such as fighting, flight or freezing.

This builds on previous research on mice lacking a functioning prefrontal cortex. These mice did not handles stress as well as their wildtype counterparts. It is theorized that a healthy balance between prefrontal cortex and periaqueductal is required for successful resolution of stress.

People with anxiety problems may have a tendency to use parts of their brain more associated with quick-response survival. This would keep them perpetually “on their toes” and unable to form a long term plan to deal with stress.

Apologies for the lack of activity. I’ve been up to my ears in drywall and paint these last few days

Autism or autistic symptoms affect roughly 1 in 500 people and yet is still a relative mystery. A new study from the New York State Institute for Basic Research in Developmental Disabilities sheds some light on the growth and proliferation of neurons in autistic individuals. It was theorized that external growth factors in serum from autistic children would affect the growth of neuronal progenitor cells, thereby simulating early neurogenesis in autistic individuals. Neuronal prgenitor cells were grown in serum from autistic children and age-matched controls, giving some interesting results.

Results and details after the jump.
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Glial cells have been regarded for years as the poor, red-headed step child to neurons in the brain. It has generally been considered that glial cells serve as support structures for neurons. The general analogy used relates glial cells to be the “glue” that holds neurons together. Glial cells perform many important (if mundane) tasks such as mopping up excess ions and recycling neurotransmiters. Glial cells also provide physical support for neurons, guide axon/dendrite growth, maintain a stable cocktail of chemicals in the fluid surrounding the brain and coat axons in myelin.

Glia, however, has always been assumed to take a backseat when the “real” work of the brain happened, watching from the sidelines as the flashy neurons communicated with eachother. Recent research may finally bring glial cells off the sideline and give them some credit they deserve. More details after the jump.

…These data indicate that glia contribute actively to the transfer and storage of information in the central nervous system. The findings reviewed above, however, are only beginning to scratch the surface of what will be an explosion of findings related to glial modulation of brain function

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After the 11 hour drive and associated unfortunate events (blown tire, among other things), I am now back at college. Which means I now have access to all the for-pay online journals. I’ve been bookmarking interesting abstracts from PubMed all summer but been unable to read the full study. Prepare for an onslaught of reports!

Before I leave for New York, I thought I’d leave you with a very interesting paper recently published on PLoS.

Here is the Author Summary:

Spatial Learning Depends on Both the Addition and Removal of New Hippocampal Neurons

The birth of adult hippocampal neurons is associated with enhanced learning and memory performance. In particular, spatial learning increases the survival and the proliferation of newborn cells, but surprisingly, it also decreases their number. Here, we hypothesized that spatial learning also depends upon the death of newborn hippocampal neurons. We examined the effect of spatial learning in the water maze on cell birth and death in the rodent hippocampus. We then determined the influence of an inhibitor of cell death on memory abilities and learning-induced changes in cell death, cell proliferation, and cell survival. We show that learning increases the elimination of the youngest newborn cells during a specific developmental period. The cell-death inhibitor impairs memory abilities and blocks the learning-induced cell death, the survival-promoting effect of learning on older newly born neurons, and the subsequent learning-induced proliferation of neural precursors. These results show that spatial learning induces cell death in the hippocampus, a phenomenon that subserves learning and is necessary for both the survival of older newly born neurons and the proliferation of neural precursors. These findings suggest that during learning, neuronal networks are sculpted by a tightly regulated selection of newly born neurons and reveal a novel mechanism mediating learning and memory in the adult brain.

I swear, walking into my local Half-Price Bookstore is like giving a kid $1000 and sending them into a toystore. I always walk in with intention to browse or purchase one book, but end up walking out with a huge pile and considerably less money in my wallet. Oh well. I am going to be away for the rest of the weekend as I’m driving back up to college. The 11 hour drive just begged for some additional reading material.

Details after the jump.
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Dave from Cognitive Daily has been working hard to getting BPR³ off the ground. It was decided a community designed icon would be the best way to go. So, without further ado, here is my contribution (obviously rough around the edges, but it only took a few minutes).

This would be the main icon, shown at the top of articles. I liked the idea of having “peers” integrated in the graphic, hence the tiny people. The image is 55×47 and weighs in at 786 bytes.

A commenter at BPR³ mentioned it would be nice to have a small icon that could go next to links, incase there were non-peer reviewed links present in the same article. So there is this little guy (15×12, 524 bytes): which can go next to links, like so:

Distributed Neuron

The tiny people in the icon were taken from the Silk Icon Set, under the Creative Commons License

It turns out digital sex is a lot more complicated than I had originally thought. A key aspect to genetic algorithms is crossover between pairs of individuals. This crossover is made to reflect the genetic pairing seen in most eukaryotes. It is an artificial way to distribute genes from the parents to the children. Crossover is important because without it, a genetic algorithm is little more than a random search. Crossover (theoretically) lets the organisms traverse the fitness landscape quicker because common building blocks are passed from parents to children.

Techniques, thoughts and a cool adaptive study after the jump.
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I began this response as a comment to an article over at The Frontal Cortex titled Reality is Fake?, but it quickly grew too long in length. My thoughts and response to Jonah after the jump.

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While this isn’t strictly neuroscience related, I thought it was interesting and relevant to my earlier post regarding implantable devices. And it was developed at my college.

Researchers at Rensselaer Polytechnic Institute have created a battery on paper. More specifically, the paper is the battery. The new battery works in a huge range of temperatures (-100 all the way to 300 degrees Fahrenheit), contains no toxic chemicals and is primarily made out of cellulose. It can also double as a high-power supercapacitor. Carbon nanotubes are integrated in the paper, which is soaked in an ionic solution. The paper is completely flexible and loses no efficiency. Furthermore, the paper sheets can be stacked like a ream of paper to boost output.

The truly important value comes from the battery’s friendly attitude towards the human body.

Paper is also extremely biocompatible and these new hybrid battery/supercapcitors have potential as power supplies for devices implanted in the body. The team printed paper batteries without adding any electrolytes, and demonstrated that naturally occurring electrolytes in human sweat, blood, and urine can be used to activate the battery device.

“It’s a way to power a small device such as a pacemaker without introducing any harsh chemicals – such as the kind that are typically found in batteries – into the body,” Pushparaj said.

The team says that the batteries are made of very cheap materials. The process to create them, however, is still too expensive to mass produce. They are working on ways to decrease the production cost. Once it becomes inexpensive to mass produce they expect it to be used in everything from cell phones to pacemakers.