The shape of thoughts.

Science Daily draws a clearer map than ever before showing how complicated networks of neurons – not individual neurons – make thoughts happen:

They do not correspond to a simple stimulus/response linkage, but arise from the networking of different neural circuits. Scientists funded by the Swiss National Science Foundation (SNSF) propose that the field of brain research should expand its focus.

Many brain researchers cannot see the forest for the trees. When they use electrodes to record the activity patterns of individual neurons, the patterns often appear chaotic and difficult to interpret. “But when you zoom out from looking at individual cells, and observe a large number of neurons instead, their global activity is very informative,” says Mattia Rigotti, a scientist at Columbia University and New York University who is supported by the SNSF and the Janggen-Pöhn-Stiftung.

Around one third of the observed neurons demonstrated activity that Rigotti describes as “mixed selectivity.” A mixed selective neuron does not always respond to the same stimulus (the flowers or the sailing boat on the screen) in the same way. Rather, its response differs as it also takes account of the activity of other neurons.