Multiple sensory afferents to ferret pseudosylvian sulcal cortex.

Abstract

While the ferret cerebral cortex is being used with increasing frequency in studies of neural processing and development, little is known regarding the organization of its associational sensory and multisensory regions. Therefore, the present investigation used neuroanatomical methods to identify non-primary visual and somatosensory representations and their potential for multisensory convergence. Tracer injections made into V1 or SI cortex labeled axon terminals within the pseudosylvian sulcal cortex (PSSC). These inputs were distributed according to modality, with visual inputs identified in the lateral aspects of the posterior dorsal bank, and somatosensory inputs found anterior along the dorsal bank, fundus and ventral bank. Somatosensory inputs showed a topographic arrangement, with inputs representing face found more anteriorly than those representing trunk regions. Overlap between these different sensory projections occurred posteriorly in the PSSC and may represent a zone of multisensory convergence. These data are consistent with the presence of associational visual, somatosensory, and multisensory areas within the PSSC.