Thalamus

Thalamus is walnut-sized centered in the brain over the brainstem. Within the thalamus are cell groups called “nuclei” based on anatomical or functional connectivity. Nuclei are based on the destination of a neural signal or type of signal being transmitted (Guillery & Sherman, 2002). The thalamus serves as “gatekeeper” of information being relayed between cortical and subcortical areas (Sherman & Guillery, 2001).  Receiving information from afferent fibers to relay to higher-order neural processing sites, such as the cortex. An increase in size in an area of the cortex mainly corresponds with an increase in size of the thalamic nucleus that transmits signals. The thalamus acts as relay between cortical regions (cortico-cortical pathways).