This study was supported by grants from the National Institute of Mental Health (MH65034 and MH06850) and by University of Maryland General Clinical Research Center Grant Number M01- RR-16500. E.S.K. was supported by an NSF graduate research fellowship.
Impaired response selection in schizophrenia: Evidence from the P3 wave and the lateralized readiness potential
Version of Record online: 6 APR 2009
Copyright © 2009 Society for Psychophysiological Research
Volume 46, Issue 4, pages 776–786, July 2009
How to Cite
Luck, S. J., Kappenman, E. S., Fuller, R. L., Robinson, B., Summerfelt, A. and Gold, J. M. (2009), Impaired response selection in schizophrenia: Evidence from the P3 wave and the lateralized readiness potential. Psychophysiology, 46: 776–786. doi: 10.1111/j.1469-8986.2009.00817.x
- Issue online: 9 JUN 2009
- Version of Record online: 6 APR 2009
- (Received July 11, 2008; Accepted September 5, 2008)
- Lateralized readiness potential;
Reaction times (RTs) are substantially prolonged in schizophrenia patients, but the latency of the P3 component is not. This suggests that the RT slowing arises from impairments in a late stage of processing. To test this hypothesis, 20 schizophrenia patients and 20 control subjects were tested in a visual oddball paradigm that was modified to allow measurement of the lateralized readiness potential (LRP), an index of stimulus-response translation processes. Difference waves were used to isolate the LRP and the P3 wave. Patients and control subjects exhibited virtually identical P3 difference waves, whereas the LRP difference wave was reduced in amplitude and delayed in latency in the patients. These results indicate that, at least in simple tasks, the delayed RTs observed in schizophrenia are primarily a consequence of impairments in the response selection and preparation processes that follow perception and categorization.