Alpha and Beta Oscillations in the Dynamics of the Areas and Weightings of the Receptive Fields of Striate Neurons in Cats in Classical and Combined Mapping

Acute experiments on 22 anesthetized and immobilized cats were performed to produce dynamic time-slices maps of 83 on and/or off receptive fields of 47 visual cortex field 17 neurons using classical and combined mapping. These experiments showed that the areas and weightings of neuron fields during response generation using classical mapping changed in a wavelike manner. Mathematical processing of these data showed that the dynamics of receptive field characteristics consisted of the sum of a slow aperiodic and a rapid periodic component. The slow aperiodic component showed biphasic receptive field dynamics. The oscillation frequency of the periodic component in most cases was distributed into the alpha and, more rarely, beta EEG ranges. Additional activation of the discharge center of the receptive field of the neuron in combined mapping had no effect on the frequency of periodic oscillations but elicited significant reductions in the duration and amplitude of the aperiodic component. The mechanisms underlying the dynamics of neuron receptive fields in the primary visual cortex are discussed, as is the functional significance of these dynamics.