Encoding of visual information: correlation of EEG response to intracellular response.

The intracellular average evoked response to full field flash in cat visual cortex was seen to have constant PSP correlates in every individual response, with a less constant relationship to spike activity. All components of the averaged evoked response in the gross EEG are explicable in the response of a single cell, including a component of latency 100 ms for which there is evidence of initiation at the apical dendrites. The data support the hypothesis that information about photostimulation is encoded at the level of the individual cell, with distortion resulting from extraneous "noise".