Natural Images, Natural Percepts and Primary Visual Cortex

old_uid1379
titleNatural Images, Natural Percepts and Primary Visual Cortex
start_date2006/06/07
schedule11h-12h
onlineno
summaryRecent psychophysical experiments indicate that humans perform near-optimal Bayesian inference in a wide variety of tasks, ranging from cue integration to decision-making to motor control. This implies that neurons both represent probability distributions and combine those distributions according to a close approximation to Bayes’ rule. At first sight, it would appear that the high variability in the responses of cortical neurons would make it difficult to implement such optimal statistical inference in cortical circuits. We argue that, in fact, this variability implies that population of neurons automatically represent probability distributions over the stimulus, a type of code we call probabilistic population codes. Moreover, we demonstrate that the Poisson-like variability observed in cortex reduces a broad class of Bayesian inference to simple linear combinations of populations of neural activity. These results hold for arbitrary probability distributions over the stimulus, for tuning curves of arbitrary shape, and for realistic neuronal variability.
responsiblesMamassian