A catalog of identified neurons, the circuits they form, and inter-species homologies.

http://blogs.spectrum.ieee.org/tech_talk/2009/01/ibm_pulls_out_of_blue_brain_co.html

Does anyone know anything more about this?

Ed

My lab, the Neuroengineering And Neuromedia Group at the MIT Media Lab, has just released a new neurotechnology. We found that just as the algal protein channelrhodopsin-2 (ChR2) can make neurons excitable by brief pulses of blue light, the mammalian codon-optimized version of the protein halorhodopsin (we abbreviate the mammalian codon-optimized form as Halo) can make neurons silenceable by brief pulses of yellow light. Furthermore, the activity of neurons expressing both Halo and ChR2 can be controlled bi-directionally by pulses of blue and yellow light respectively. This toolbox enables extremely sophisticated new kinds of experiment – such as being able to desynchronize neuronal spiking (without altering mean spike rate)! The paper just came out in PLoSONE, a new PLoS journal that encourages papers to become living documents — any reader can comment on any paper.

You can check out, and then comment on, the paper, “Multiple-color optical activation, silencing, and desynchronization of neural activity, with single-spike temporal resolution,” here.

– Ed

Given these findings, we predict that fluctuations in free or Mg2+-bound ATP will affect the signal output of most—if not all—CFP-YFP–based FRET indicators.

The authors continue with the following recommendations:

Currently, not much is known about effects of intracellular molecular crowding or the occurrence of local fluctuations in ATP concentration in distinct cellular locales, including the unstirred molecular layers in the vicinity of membranes8, 9. We think, however, that the dynamic concentration(s) of compartmentalized local free Mg-ATP will almost certainly overlap the 1–20 mM range, or be even higher. Thus, our observations may have important implications for microscopy studies of a broad range of local signaling events or metabolite changes in a broad range of cells. Findings should be interpreted with caution if genetically encoded CFP-YFP–based biosensors are used in cells with large and sudden fluctuations in local or global ATP concentration and appropriate controls with bound and nonbound ligands and CFP and YFP placed at appropriate spacing should be used at all times.

Source: ATP and FRET—a cautionary note
Marieke Willemse, et al. (Feb. 2007)

NIPS 2006 Workshop Announcement and Call for Abstracts
Decoding the Neural Code

There is great interest in sensory coding. Studies of sensory coding typically involve recording from sensory neurons during stimulus presentation, and the investigators determine which aspects of the neuronal response are most informative about the stimulus. These studies are left with a decoding problem: are the discovered codes, sometimes quite exotic, ultimately used by the nervous system to guide behavior? In our one-day workshop, researchers with many different backgrounds will evaluate what we know about neuronal decoders and suggest new strategies, both experimental and computational, for addressing the decoding problem.

Each hour, five to six researchers will address a particular question for five minutes, followed by a half-hour discussion. We will also set aside time for a poster session.

We tentatively plan to include the following questions, and are soliciting additional questions from our speakers:
1. Which variables that encode stimuli are actually used to guide behavior?
2. What mechanisms do nervous systems use to decode encoded information?
3. Are motor systems better than sensory systems for experimentally addressing decoding?
4. What computational and experimental techniques are needed to address decoding? For instance, should information theory be used to address decoding as well as encoding?

For information on abstract submission, go to the workshop web site at http://science.ethomson.net/NIPS_workshop.html.

Details here:

http://www.netflixprize.com/

Wang X, Lou N, Xu Q, Tian GF, Peng WG, Han X, Kang J, Takano T, Nedergaard M.
Astrocytic Ca2+ signaling evoked by sensory stimulation in vivo.
Nat Neurosci. 2006 Jun;9(6):816-23.

Predictability
words and music by Dr. BLT (c)2006

http://www.drblt.net/music/predict.mp3

and we turn to the supernatural when we are comfortable with the idea of not having to predict and control everything.