AUDITORY, SOMATIC SENSORY, AND VISUAL RESPONSE INTERACTIONS AND INTERRELATIONS IN ASSOCIATION AND PRIMARY CORTICAL FIELDS OF THE CAT

Abstract

Interactions and intercorrelations of cortical association and primary responses to auditory, somatic sensory, and visual stimuli in the cat were studied. Relatively and absolutely unresponsive periods for response amplitude to the second of two stimuli were found to be much longer for association than primary responses. Further, the same recovery cycle was found for association response amplitudes to the second of two stimuli of different modalities as was found for the same stimulus delivered twice. Correlational analyses demonstrated perfect correlations between response amplitudes recorded simultaneously in any two association response fields to any modality of stimulation, this in spite of the very large variability of association responses. Correlations of association and corresponding primary response amplitudes were all zero. All of the data are consistent with the hypothesis that a peripheral stimulus of any modality activates one and the same central association system in an undifferentiated manner This system projects in an equivalent fashion to the same four cortical fields. Visual responses of the suprasylvian sulcus (Vss) were found to be unrelated to association responses, and not to interact with primary auditory responses.