Thursday, April 29, 2010

Seeing a Living Brain Seeing

"To find out more about the input signal, Konnerth and his colleagues observed a mouse in the act of seeing, with resolution that goes beyond a single nerve cell to a single synapse. They refined a method called two-photon fluorescence microscopy, which makes it possible to look up to half a millimeter into brain tissue and view not only an individual cell, but even its fine dendrites."

"And this," Konnerth says, "is where things get really exciting." The orientation neuron only sends output signals when, for example, the bar pattern moves from bottom to top. Evidently the neuron weighs the various input signals against each other and thus reduces the glut of incoming data to the most essential information needed for clear perception of motion."
Maybe I'm just getting old, but hasn't this been the basis of all connectionist models for the past 30 years?