| Nonlinear Dynamics, Psychology, and Life Sciences, Vol. 3, Iss. 1, Jan, 1999, pp. 49-63 @1999 Society for Chaos Theory in Psychology & Life Sciences Estimation of Correlation Dimension to Evaluate Cognitive Performance in Schizophrenic Patients Using a New Computer Technique Abstract: A new cognitive-motor, computer-administered instrument, the Random Rhythm Generation test (ARG), measured the schizophrenics' and control subjects' capacity of performing random (aleatory) rhythms. The interval frequencies between subjects' responses and chaotic dynamic attractor of the generated series, expressed in the phase space and correlation dimension, were analyzed. Results showed that schizophrenic patients (SG) generated more regular and rhythmic series than those of the control group (CG) when performing the ARG (correlation dimension in SG = 2.796 +/- 0.47, in CG = 3.842 +/- 0.51, p lt; 0.01). Therefore, the ARG may be use fill for the estimation and quantification of the cognitive-motor dysfunction in schizophrenic patients and possible definitions of treatments of cognitive and psychomotor dysfunctions. Our results also suggest that schizophrenic patients are characterized by more regular and rhythmic patterns than control subjects. Keywords: schizophrenia, attractor, correlation dimension |