Authors

Crespo-Facorro B. Paradiso S. Andreasen NC. O'Leary DS. Watkins GL.

Boles Ponto LL. Hichwa RD.

 

Institution

Mental Health Clinical Research Center, Department of Psychiatry, College of

Medicine, University of Iowa Hospitals and Clinics, USA.

 

Title

Recalling word lists reveals "cognitive dysmetria" in schizophrenia: a

positron emission tomography study.

 

Source

American Journal of Psychiatry. 156(3):386-92, 1999 Mar.

 

Abstract

OBJECTIVE: This study explored the neural circuitry used during recall of

unstructured verbal material in schizophrenic patients and healthy volunteer

subjects. METHOD: The subjects were 13 healthy volunteers and 14

schizophrenic patients. All patients were free of medication, and all

subjects were right-handed. Two experimental cognitive conditions were used:

recall of novel and practiced word lists (two 15-item lists from the Rey

Auditory Verbal Learning Test). Both active recall tasks were compared with

an eyes-closed resting baseline condition. A nonparametric randomization test

was used to determine within- and between-group differences in regional

cerebral blood flow. RESULTS: Performance on both the practiced and novel

memory tasks was nonsignificantly different in the patients and control

subjects. During the novel memory task, the patients showed decreased flow in

the right anterior cingulate, right thalamus, and bilateral cerebellum (left

greater than right) relative to the control subjects. When recalling the

practiced word lists, the patients showed decreased flow in the left

dorsolateral prefrontal cortex, bilateral medial frontal cortex, left

supplementary motor area, left thalamus, left cerebellar regions, anterior

vermis, and right cuneus. CONCLUSIONS: Patients with schizophrenia fail to

activate cortical-cerebellar-thalamic-cortical circuitry during recall of

both well-learned and novel word lists.