Archive for the ‘At the scale of one or more individuals’ Category

Plant neuroscience

Tuesday, June 10th, 2008

Plants Found to Show Preferences for Their Relatives - NYTimes.com

Two amazing things here:

  1. Plants missing photosynthetic enzymes of their own that migrate directionally toward “victim” plants. This behavior has an uncanny resemblance to axon guidance. Make sure to view the time-lapse video in the NYT article. Here’s an image from the PSU website:

  2. Plants capable of identifying kin and “being nice” to kin while going into a competitive mode of root growth with non-kin. Amazing.

It refreshing to see this kind of interesting behavior without any neurons involved. It makes me think (realize) that the idea of a neuron or a neural system has many components and there might not be any good reason to assume that a single cell must have all of those properties or none of them. Something like a neuron-like cell that’s not a neuron in the classical sense. Anyone know of other examples?

Some experiments on baboon social cognition

Wednesday, October 10th, 2007

Nytimes article.

Summary after the break.

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Your Brain Is A Cartographer

Tuesday, September 11th, 2007

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.

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Bad-ass squirrels

Friday, August 24th, 2007

In the new issue of PNAS, a totally awesome discovery about an infrared inter-species signalling system:

Ground squirrels not only heat up their tails to deter snake attacks — but they also seem to use the strategy selectively against infrared-sensitive snakes — leading us to the ultimate conclusion that when the bees are gone, the squirrels will inherit the earth…

You can check out an infrared-eye-view of squirrel/snake battles here because I don’t know how to post movies on the internet yet

–Davie

Severe lifelong case of hydrocephalus but IQ of 75

Friday, August 10th, 2007

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.

Age-dependent brainwashing in bees

Monday, July 23rd, 2007

Apparently, when not busy blowing our minds, bees occupy themselves by…

…brainwashing their youth

…and/or mysteriously disappearing from the face of the earth

Keeping an eye on species poised to take over the world,
Davie

Time for neuroscientists to speak up?

Wednesday, July 18th, 2007

Recently, I was pointed to this article in the WSJ (”A Pentagon Agency Is Looking at Brains — And Raising Eyebrows“) by Sharon Begley. It touches on some noninvasive recording techniques for assessing affective state and cognitive enhancers like ampakine CX717 (previously mentioned on Neurodudes here and here).

It was the very last paragraph that caught my eye:

Ever since the atomic bomb, physicists have known that their work has potential military uses, and have spoken up about it. But on the morality of sending orders directly to the brain (of a soldier, employee, child, prisoner …), or of devices that read thoughts and intentions from afar, neuroscientists have been strangely silent. The time to speak up is before the genie is out of the bottle.

Whoa! To me, the physicists who spoke out early on against nuclear proliferation seemed (and still seem) both very courageous and prescient in their ideas. Are we neuroscientists dropping the ball? I would love to start a discussion on this subject and to hear your responses (both from neuro people and others) in the comments below.

I’ll start: I personally don’t think the arena of neural enhancement/intrusion (mind reading, mind control, cognitive enhancement, etc.) is comparable to the sheer destructive power of nuclear weapons. I do see in the near future the unfortunate potential for abuse of neurotechnology and violation of personal freedoms, but the threat does not seem as horrifying or deadly. Still, if neurotechnology allows governments greater control over their citizens, it seems reasonable that scientists who enable such technologies should intervene. Perhaps it is time for a neural bill of rights, which, similar to the freedoms granted by the US Bill of Rights, will clearly state what aspects of a person’s mental state or capacity cannot be infringed upon without permission from that person. Thoughts?

Bilaterally symmetrical animals share a common ancestor with a CNS?

Tuesday, July 17th, 2007

The common ancestor of Bilateria ( ~= bilaterally symmetric animals ~= “most animals including vertebrates, arthropods, molluscs, etc” - - tolweb) is thought to have had a nervous system. Question: did it have a centralized nervous system? Or did centralization in the nervous system evolve separately in chordates and in other bilaterally symmetric animals?

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Williams syndrome nytimes article

Monday, July 9th, 2007

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

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22 human-specific micro RNAs

Thursday, June 21st, 2007

This article (from last December) has identified what it thinks are 244 new human microRNAs from human fetal brain tissue, of which 20 seem to be species-specific (see figure 1d). They also mention 2 previously-known human-specific microRNAs.

Eugene Berezikov, Fritz Thuemmler, Linda W van Laake1, Ivanela Kondova, Ronald Bontrop, Edwin Cuppen and Ronald H A Plasterk Diversity of microRNAs in human and chimpanzee brain. Nature Genetics - 38, 1375 - 1377 (2006)