neurodudes

The concept that the brain holds maps of the surface of the body in the primary sensory and motor cortex is a fascinating but well known fact to the field of neuroscience since the early work of Wilder Penfield. What is less broadly appreciated is the concept of “peripersonal space”. A new book by Sandra and Matthew Blakeslee describes peripersonal space in the following way:

The maps that encode your physical body are connected directly, immediately, personally to a map of every point in that space and also map out your potential to perform actions in that space. Your self does not end where your flesh ends, but suffuses and blends with the world, including other beings. [...] Your brain also faithfully maps the space beyond your body when you enter it using tools. Take hold of a long stick and tap it on the ground. As far as your brain is concerned, your hand now extends to the tip of that stick. [...] Moreover, this annexed peripersonal space is not static, like an aura. It is elastic. [...] It morphs every time you put on or take off clothes, wear skis or scuba gear, or wield any tool. [...] When you eat with a knife and fork, your peripersonal space grows to envelop them. Brain cells that normally represent space no farther out than your fingertips expand their fields of awareness outward, along the length of each utensil, making them part of you.

What I appreciate about this, besides the stretchy comic book characters that it makes me think about, is that it provides a powerful perspective to begin piecing together a mass of disparate neuroscience data, which the Blakeslee’s capitalize on.

(more…)

Happy Labor Day (US)! Topping the NYT most popular articles list right now is an interesting article about a new schizophrenia treatment that targets certain glutamate receptors unlike previous dopaminergic drugs. The drug, which is being developed by Eli Lilly, is partially due to this interesting observation:

For decades, psychiatrists have known that users of PCP, a street drug sometimes called angel dust, have symptoms nearly identical to those of people with schizophrenia. By the 1980s, scientists had discovered that PCP blocked brain receptors that are triggered by an amino acid called glutamate. This led some companies and scientists to study ways to stimulate glutamate receptors as a treatment for schizophrenia.

But the brain has many different kinds of glutamate receptors, and figuring out how to stimulate or block them in medically beneficial ways has proved complicated. Instead of focusing on the receptors blocked by PCP, Dr. Schoepp concentrated on modulating the action of glutamate receptors in the brain’s prefrontal cortex, an area responsible for personality and learning.

(more…)

From the department of “we are living in a sci-fi movie”, here’s a video of a bionic arm that uses “fluidic muscles”.

The original slashdot article is here.

(more…)

“It sounds like a science-fiction version of stupid pet tricks: by toggling a light switch, neuroscientists can set fruit flies a-leaping and mice a-twirling and stop worms in their squiggling tracks. But such feats, unveiled in the past two years, are proof that a new generation of genetic and optical technology can give researchers unprecedented power to turn on and off targeted sets of cells in the brain, and to do so by remote control…”

Reviews the use of photosensitive proteins in neuroscience and even gives a shout-out to Ed Boyden, of Stanford and MIT fame…

– Davie (who had the same advisor as Ed for about a day and is therefore 0.01% more famous by association)

The man had a normal job and is a married father of two children.

Nature news

Lionel Feuillet, Henry Dufour and Jean Pelletier. Brain of a white-collar worker. The Lancet, Volume 370, Issue 9583, 21 July 2007-27 July 2007, Page 262.

A patient who had been in a “minimally conscious state” for six years regained responsiveness after stimulation via electrodes implanted in the thalamus. Now he can “name objects on request, make precise hand gestures, and chew food without the aid of a feeding tube”.

(more…)

http://www.nytimes.com/2007/07/08/magazine/08sociability-t.html

(more…)

This study provides fMRI evidence that, after forgetting some memories, the brain has to work less hard.

(more…)

Read on for a guest-posted ad for WNYC’s radio lab (http://www.radiolab.org)

(more…)

The MIT Media Lab is holding a conference on May 9th, “Human 2.0: New Minds, New Bodies, New Identites” which will launch a number of new initiatives centered around the goal of inventing a better future via direct engineering of the human. Amongst these things will be the initiation of the MIT Center for Human Augmentation, and the launch of a number of novel applied Neurotechnology Projects.

Guest speakers on May 9th will include MIT professors (Roz Picard, Hugh Herr, myself, etc.) and many acclaimed speakers such as Oliver Sacks and John Donoghue. Registration may be close to being full, but it will be webcast.

More information at:
http://h20.media.mit.edu

- Ed