Stop and Go

The above image comes from a CNRS press release about the “double personality” of inhibitor neurons. Oh, and yes, the press release is in French. Sorry ’bout that. CNRS maintains an English site as well, but it lags several weeks behind the French site (shocking, I know).

Basically, researchers have discovered a chemical basis for the function of inhibitor neurons—neurons that seem to play a role in disorders such as paralysis and epilepsy. According to the new findings, the firing of a neuron (“stop” and “go,” as it’s described in the figure above) depends on the concentration of chloride ions, which is in turn controlled by proteins in the surface of the neuron.

To my eye, the visualization (presumably of actual data) communicates its message quite clearly. First off, it capitalizes on existing color associations with “stop” (red) and “go” (green), but it also does a nice job of highlighting specific regions of the neuron (n.b. “stop or go” and “stop or go”). A lot of information in a small space. The little diagram on the upper left is far too small for me to make out, but I’m guessing that it contains information that I would find interesting were I able to read it.

The red-green color scheme also seems to correlate with the use of bioluminescent tags in various samples. The book Aglow in the Dark: The Revolutionary Science of Biofluorescence taught me a wee bit about this field. Fascinating stuff.

Face Off

Another brief posting. I ran across an article on EurekAlert claiming that “facial composite systems falling short” that got me looking for a representative image. The one above comes from a 2002 CNN article that implies that such software ives us an “edge over bad guys.” The new study suggests something different, as you might guess.

“In one particular study, only 2.8 percent of participants correctly named a well-known celebrity that had been created by other participants using the face-composite software. In a separate study, participants were unable to discriminate composites of their classmates from composites of students at entirely different schools.”

Doesn’t bode well, eh?

What this underscores is the difference between how the brain processes imagery verus how computer software (for example) processes imagery. As one researcher is quoted, “faces are generally processed, stored and retrieved at a holistic level rather than at the level of individual facial features,” which contrasts with a generally reductionist scientific perspective.

Hmmm. Maybe I noticed this story because of my recent experience in S.F. and because I’ve been warned by several people to watch out here in New Orleans (as one friend put it, “think port city in Victorian England”).