Cortical Dynamics of Perception as Trains of Coherent Gamma Oscillations, with the Pulvinar as Central Coordinator

Abstract

Abstract Synchronization of spikes carried by the visual streams is strategic for the proper binding of cortical assemblies, hence for the perception of visual objects as coherent units. Perception of a complex visual scene involves multiple trains of gamma oscillations, coexisting at each stage in visual and associative cortex. Here, we analyze how these trains are managed, so that the perception of each visual object can emerge despite this complex interweaving of cortical activations. After a brief review of structural and temporal facts, we analyze how these oscillations are made coherent for all elements related to the same visual object. We continue with the propagation of these gamma oscillations within the sensory chain. The dominant role of the pulvinar as cortical coordinator is the common thread running through this step-by-step description. Cortical mechanisms are analyzed in the context of visual perception, although the present considerations are not limited to this sense. An experiment is described, with the aim of assessing the validity of the elements developed here. An initial set of results is provided, together with a proposed method to go further in this investigation.