Neuropsychiatric Significance of Subcortical Encephalomalacia: Implications for Mood Disorders

Abstract

Subcortical hyperintensity (foci of increased signal on T-2-weighted MR imaging) is associated with aging, vascular disease, and overall medical burden. Pathological data suggest that subcortical hyperintensity reflects the effects of brain hypoperfusion to subcortical regions. In otherwise healthy aging adults, the severity of subcortical hyperintensity is associated with dysequilibrium, cognitive dysfunction, and changes in brain function (decreased coherence, regional cerebral blood flow, and cerebral metabolism). Subcortical hyperintensity is also associated with mood disorders, particularly major depression in the elderly (especially of late-age onset) and possibly also major depression and bipolar disorder in nonelderly populations. In these patients, subcortical hyperintensity is predictive of cognitive dysfunction and possibly also treatment outcomes.