Antipsychotics and brain changes.

The use of antipsychotic drugs, rather than the action of a distinct disease process, appears to bloat the volume of several innerbrain regions in people diagnosed with schizophrenia, according to a team of neuroscientists.

The researchers, led by Raquel E. Gur of the University of Pennsylvania Medical Center in Philadelphia, administered magnetic resonance imaging (MRI) scans to 96 psychiatric patients with schizophrenia--a severe disturbance of thought and mood--and 128 people who had no psychiatric ailments. Of the patients, 21 had never taken antipsychotic medication, 48 had received only haloperidol or other traditional antipsychotics for about 3 years, and 27 had used both traditional and newer medications, such as clozapine, over a similar period.

The volume of the basal ganglia was markedly greater in medication-treated patients than in both drug-free patients and healthy volunteers, the scientists report in the December AMERICAN JOURNAL OF PSYCHIATRY. The basal ganglia consist of clumps of tissue involved in the regulation of movement and thinking. They showed the greatest volume in patients who had taken high doses of traditional antipsychotic drugs.

Medication-free patients differed from healthy volunteers only by having a smaller thalamus, Gur and her coworkers say. Disturbances in this structure, which helps to focus attention and filter sensations, have already been implicated in schizophrenia (SN: 10/29/94, p. 284). -- B.B.