From Receptive Field Dynamics to the Rate of Transmitted Information: Some Facets of the Thalamocortical Auditory System

Abstract

In this article, we first evaluate the literature describing reorganizations of auditory cortex topography after behavioral training. We then review the studies showing that receptive fields of auditory thalamocortical neurons express large dynamics in unanesthetized animals. During the time course of different behavioral training protocols, the frequency tuning curves of thalamocortical neurons can be selectively modified to code for the learned importance of acoustic stimuli. In other circumstances, when the vigilance state shifts from waking to sleep, the functional properties of thalamic and cortical neurons exhibit drastic modifications. Finally, we point out new lines of research. First, investigations describing the responses of neurons to communication signals (e.g. species-specific vocalizations) are important because they reveal how the thalamocortical auditory system processes biologically relevant sounds. Second, we suggest that the spike timing precision can largely increase the amount of information transmitted in the thalamocortical auditory system. This urges for more systematic studies in which the temporal organization of spike trains will be considered at presentation of natural stimuli.