Reaction time decomposition and 1-back working memory tasks in drug naive and neuroleptically treated schizophrenic first-onset patients and healthy controls

Recently (1) we demonstrated that with „1-back continuous delayed response“ tasks a nearly complete separation between healthy subjects and drug-naive first-onset patients is possible. The difference could be explained be a different organisation of task solving. The present investigation addresses the question how a successful neuroleptic treatment effects these working memory functions.

Method: Additionally to each of the 12 drug-naive patients and 12 healthy controls of (1) 12 neuroleptically treated first-onset patients were matched. As reaction-time-decomposition paradigm simple, discriminative and choice reaction as well as 1-back continuous delayed response and matching tasks were presented.

Results: Both schizophrenic groups needed more time to solve working memory tasks. However, whereas in untreated patients the lengthening can be explained by a different organisation of task solving, in treated schizophrenics the difference is caused by an increased duration of simple reaction time.

Discussion: The preliminary results indicate that at least in a subgroup of schizophrenics a successful neuroleptic treatment causes a re-organisation of cognitive processes involved in working memory.

1. KriegerS. et.al. Am.J.Psychiat, subm.