A point process analysis of sensory encoding

Nowhere is the sparse nature of neuronal coding more evident than in the sensory cortex, where neuronal response becomes increasingly tuned to specific features of the sensory environment. For such situations, where rate modulation schemes do not accurately describe the neuronal response to sensory stimuli, statistical descriptions based on point process events are particularly appropriate. Intensity measures derived from experimental data in the rat somatosensory cortex enable the direct analysis of statistical structure within spike trains, as well as inter-relationships between tactile stimuli and neuronal response. Intensity measures capture structure in spontaneous as well as driven activity, and provide a means for simulation and/or prediction. Second order intensities reveal strong dependencies upon temporal patterns of tactile stimulation, which are at least partly responsible for frequency dependent adaptation characteristics in neuronal response.