Role of the claustrum in sensory activation.

The functional organization of the claustrum was studied in acute experiments in cats from birth to adulthood. No somatotopic organization was found, but, on the contrary, multisensory convergence was confirmed. The significance of the claustrum for somesthetic and acoustic afferentation is emphasized. The claustrum is activated mainly by a "cortical loop", along the following route: the diencephalic nuclei (the relevant modality system) leads to cortical projection areas (including secondary and probably association areas) leads to the claustrum. All the correlations described exist from the very first period of postnatal development.