Patients' awareness of extrapyramidal reactions to neuroleptic drugs: possible evidence for the role of catecholamines in perception.

The awareness of extrapyramidal reactions during initiation of neuroleptic treatment was studied in 14 patients. Only one patient spontaneously identified the presence of dystonia. The other 13, including 3 who had experienced extrapyramidal reactions during previous hospitalizations, did not fully identify the presence of symptoms, although several had vague discomfort. There was marked variability in acknowledgement of symptoms in response to prompting by staff members. The findings are similar to reports of agnosia for hemiparesis after parietal lobe injury and also to descriptions of agnosia in animals caused by destruction of dopaminergic neurons. Since extrapyramidal reactions represent blockade of dopaminergic neurotransmission, patients' inability to perceive the reactions may represent evidence for catecholaminergic modulation of sensory perception.