[Functional analysis of evoked potentials in rat sensory cortex]

In the barrel cortex of behaving rat potentials evoked to vibrissa stimulation are composed from two main principal components which can be attributed to activation of two pyramidal cell populations: supra- and infragranular. The classical aversive stimulus favors the appearance of EPs dominated by a component characteristic of infragranular cells. We hypothesize that neuromodulatory action elicited by contextual stimulation activates all involved cortical neurons which results in opening the transmission gate to the surrounding columns.