ABSTRACT
The subcortical structures that have frequently been implicated in HIVrelated neurologic disease, such as the basal ganglia and thalamus, are known to mediate specific cognitive and motor functions. Fine motor imprecision, psychomotor slowing, hypophonia (lowered volume of speaking), bradyphrenia (slowed information processing), a forgetful pattern of memory impairment, and difficulty on complex cognitive tasks, such as shifting of mental set and planning/strategy formation, have all been documented in diseases differentially implicating subcortical structures, including their rich connection to the frontal lobes of the brain. This produces a similar pattern of cognitive and motor impairment to that found in patients with other dementias resulting from predominantly subcortical pathology, such as Parkinson's disease and Huntington's disease. Damage to some subcortical structures has also been reported to result in delusions, mania, and depression (Cummings, 1990).
