Melvin Lyon1, Aaron S Kemp. 1. Neurocognitive Development Laboratory, University of Southern California, CEM Building, Room 206, University Park, Los Angeles, CA 90089, USA. mlyon@usc.edu
Abstract
RATIONALE: The THEME method for measuring time-determined patterns (T-patterns) in behavior has been suggested as a new, more objective method for assessing cognitive disturbances in schizophrenia. OBJECTIVES: THEME was used to compare responses of schizophrenic patients with those having mood, schizoaffective, or severe anxiety disorders, and with healthy control subjects. METHODS: A two-choice, button-pressing task was used to elicit T-patterns among responses, with knowledge-of-results (K) rewards and coin reinforcements (RF) as reinforcers. Subjects were compared by diagnosis, drug treatment, and gender. RESULTS: Schizophrenic and manic patients showed excessive numbers of, and more complex T-patterns than controls. Schizophrenic and manic patients frequently demonstrated repetitive (stereotyped) responding, an effect never seen in healthy controls. Although clozapine (CLZ) reduced both excessive T-pattern structure and stereotyped responding, it also reduced growth of responding to the coin RF. CONCLUSIONS: Significant T-pattern increases may represent a common, time-related symptom of schizophrenia and mania. CLZ's effect on T-pattern production suggests that receptor effects other than the DAD(2) antagonism of "typical" neuroleptics' may be relevant to these findings.
RATIONALE: The THEME method for measuring time-determined patterns (T-patterns) in behavior has been suggested as a new, more objective method for assessing cognitive disturbances in schizophrenia. OBJECTIVES: THEME was used to compare responses of schizophrenicpatients with those having mood, schizoaffective, or severe anxiety disorders, and with healthy control subjects. METHODS: A two-choice, button-pressing task was used to elicit T-patterns among responses, with knowledge-of-results (K) rewards and coin reinforcements (RF) as reinforcers. Subjects were compared by diagnosis, drug treatment, and gender. RESULTS:Schizophrenic and manicpatients showed excessive numbers of, and more complex T-patterns than controls. Schizophrenic and manicpatients frequently demonstrated repetitive (stereotyped) responding, an effect never seen in healthy controls. Although clozapine (CLZ) reduced both excessive T-pattern structure and stereotyped responding, it also reduced growth of responding to the coin RF. CONCLUSIONS: Significant T-pattern increases may represent a common, time-related symptom of schizophrenia and mania. CLZ's effect on T-pattern production suggests that receptor effects other than the DAD(2) antagonism of "typical" neuroleptics' may be relevant to these findings.
Authors: Aaron S Kemp; Paul T Fillmore; Mohammed R Lenjavi; Melvin Lyon; Aleksandra Chicz-Demet; Paul E Touchette; Curt A Sandman Journal: Psychiatry Res Date: 2007-10-25 Impact factor: 3.222