Though the subcortical white matter (SWM) has been traditionally considered a site for passive information transfer through cerebral cortex association and projection axonal fibers, recent studies performed on infant and adult human and non-human primate SWM cells, report the expression of immunolabelled neurotransmitters/neuromodulators and synaptic vesicular proteins in resident neuronal and glial cells. These observations strongly suggest the need to review current concepts on the structural and dynamic characteristics of the SWM and its role in functional brain integration and information management. New experimental research chimeras are needed to ascertain neuronal and glial SWM cells’ physiological role in information transmission within the SWM and their integration and interaction with gray substance regional cortical circuits.