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A patient with prominent apathy secondary to multiple subcortical infarcts was treated successfully with methylphenidate. SPECT and reaction time testing showed selective improvement of frontal system function, consistent with a recent model of frontal-subcortical circuits and behavior.

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In a preliminary study, 30 nondemented human immunodeficiency virus (HIV-1) seropositive subjects without acquired immunodeficiency syndrome and 14 seronegative controls performed a reaction time measure of spatial attention. Compared with controls, seropositive asymptomatic subjects showed normal facilitation of reaction time at short cue-target intervals when attention was precued, but symptomatic subjects were impaired. However, asymptomatic subjects showed no evidence of normal inhibition of attention at the cued location at longer cue-target intervals, suggesting possible subtler spatial attentional deficits in this group. Cognitive slowing in HIV-1 infection may have an attentional component, with possible involvement of both automatic and controlled processes.

We studied the outcome of 10 patients who had undergone high-risk surgery for an arteriovenous malformation at our institution between November 1991 and November 1993. All of the lesions were located in the dominant (left) hemisphere. Perioperative risk was assessed by the location of the lesion in functionally eloquent cortex (seven patients) or deep structures (two patients) or the lesion's large volume (two patients). Our patients included six women and four men, and their ages ranged from 22 to 53 years (mean, 35.8). Our follow-up study included the evaluation of neurological sequelae but mainly emphasized the study of cognitive deficits (seven major functional clusters), the incidence of depression and behavioral changes, and the assessment of regional cerebral blood flow with single photon emission computed tomography. Six patients returned to a seemingly "normal" daily life with some minor deficits postoperatively, three developed contralateral hemiparesis, and one had disabling cognitive deficits. Our comprehensive cognitive assessment, in particular, showed that although patients might appear "normal" on a routine neurological examination, most patients showed a mild deficit in at least one cognitive function and three were severely impaired. In addition, the single photon emission computed tomographic studies pointed out hypoperfusion in more extensive regions than the surgical defects shown by magnetic resonance imaging or computed tomographic studies. These single photon emission computed tomography images helped to explain some of the cognitive and behavioral changes better than the anatomic studies. This information will make it possible for the physician to offer continuing supportive care for the patient in postoperative transition to normal life activities.