The Thalamic Bridge to Cognition and Consciousness

Abstract

From an evolutionary perspective, deeper brain structures are postulated as being more primitive than those that were developed later on. As such, the thalamus, being a deep brain structure, is generally believed to occupy one such primitive role: that of a ‘sensory relay station’. Recent evidence, however, suggests that the thalamus is in fact responsible for more complex and higher order functions involving cognition and consciousness, processes previously attributed solely to the cerebral cortex. This review examines several of these emerging theories through the lens neural pathways, with particular focus placed on how the complex circuitry of the thalamus allows for the intricate connectivity between itself, the cerebral cortex, and other subcortical structures.