The typical apathetic state of tardive dyskinesia patients may be punctuated by periods of hyperactivity, vigilance, and tension. Patients may exhibit unusual readiness for contact, even though they remain edgy, loud and loquacious, euphoric, jolly, intrusive, and invasive of the privacy of others. These features designated as "tardive dysmentia" are examined, so as to draw attention to the possibility that the syndrome of dysmentia is comprised of occasional excessive emotional reactivity, enhanced responsiveness to environmental stimuli, and indifference to or reduced awareness of the patient's abnormal involuntary movements. The pathophysiology of tardive dysmentia remains uncertain. It is proposed that behavioral changes in patients with dysmentia may be conceived in terms of a more outward direction of attentional processing. Such an immense change in psychopathology under antipsychotic drugs, from withdrawal to the emotional externalization of behavior, is conceived as reflecting a shift in the approach-avoidance behavior due to alterations in the parieto-frontal balance.