Pharmacopsychiatry 2003; 36 - 177
DOI: 10.1055/s-2003-825428

Different aspects of executive function in first episode schizophrenia

K Ludewig 1, S Ludewig 1, P Martin 2
  • 1Psychiatric Services of Aargau Canton, Department of Research, Brugg, Switzerland
  • 2Laboratory of Biological Dynamics and Theoretical Medicine, University of California San Diego, San Diego, CA, USA

Executive functions encompass a group of cognitive processes, that include planning, strategy-use, set-shifting, divided attention, and working memory. The results of studies measuring executive functions in first-episode schizophrenia are inconsistent. The aim of this study was to investigate different aspects of executive functions in first-episode schizophrenia.

First-episode schizophrenia patients and healthy controls performed the two-choice guessing task (decision-making), Stockings of Cambridge (planning abilities), Intra-/Extradimensional Set Shifting (rule acquisition and reversal and extradimensional set shifting), Rapid Visual Information Processing (sustained attention). We found impaired executive functions in first-episode schizophrenia, including measures of decision-making, planning, strategy use, rule acquisition and a statistical trend in decreased set-shifting. First-episode schizophrenia showed also markedly decreased sustained attention. We found no relationship between measures of attention and executive function, whereas there were correlations between different executive functions.

These results indicate that schizophrenia patients at the beginning of their illness exhibit deficient executive functions. Furthermore, decision-making dysfunctions are not due to a deficient attentional resource allocation, but related to set-shifting and planning dysfunctions.