title: Organization of receptive fields of tonic and phasic neurons of the pulvinar in the cat.
abstract: The receptive fields (RF) of 163 neurons of the pulvinar were investigated by the method of point testing the RF surface with a stationary, flashing light spot. The RFs of 26% of the neurons were characterized by a phasic pattern of response in all regions studied, while the RFs of 15% of the neurons consisted of only tonic elements. A complex RF organization, consisting of tonic and phasic subfields, was characteristic of 59% of the neurons. On the basis of this fact the postulate is advanced concerning the convergence of two types of afferents on a single pulvinar neuron. The cell population receiving inputs from purely tonic or purely phasic afferents comprises 41% of all cells investigated. The measurement of the latent periods of neuron responses to a stationary, flashing light spot showed that neurons with a phasic type of response are distinguished by a shorter latent period compared to neurons with tonic and mixed types of responses.
mesh_terms: D000818:Animals; D002415:Cats; D009474:Neurons / Q000502:physiology*; D010775:Photic Stimulation; D013788:Thalamus / Q000502:physiology*; D014796:Visual Perception / Q000502:physiology*