Erin K Moran1, James M Gold2, Cameron S Carter3, Angus W MacDonald4, J Daniel Ragland3, Steven M Silverstein5, Steven J Luck6, Deanna M Barch1,7,8. 1. Department of Psychiatry, Washington University School of Medicine, St. Louis, MO, USA. 2. Department of Psychiatry, Maryland Psychiatric Research Center, University of Maryland School of Medicine, Baltimore, MD, USA. 3. Department of Psychiatry, University of California, Davis, CA, USA. 4. Department of Psychology, University of Minnesota, Minneapolis, MN, USA. 5. Department of Psychiatry, Rutgers Robert Wood Johnson Medical School Hospital, Piscataway, NJ, USA. 6. Department of Psychology, University of California, Davis, CA, USA. 7. Department of Psychological & Brain Sciences, Washington University in St. Louis, St. Louis, MO, USA. 8. Department of Radiology, Mallinckrodt Institute of Radiology, Washington University School of Medicine, St. Louis, MO, USA.
Abstract
BACKGROUND: Schizophrenia is a disorder characterized by pervasive deficits in cognitive functioning. However, few well-powered studies have examined the degree to which cognitive performance is impaired even among individuals with schizophrenia not currently on antipsychotic medications using a wide range of cognitive and reinforcement learning measures derived from cognitive neuroscience. Such research is particularly needed in the domain of reinforcement learning, given the central role of dopamine in reinforcement learning, and the potential impact of antipsychotic medications on dopamine function. METHODS: The present study sought to fill this gap by examining healthy controls (N = 75), unmedicated (N = 48) and medicated (N = 148) individuals with schizophrenia. Participants were recruited across five sites as part of the CNTRaCS Consortium to complete tasks assessing processing speed, cognitive control, working memory, verbal learning, relational encoding and retrieval, visual integration and reinforcement learning. RESULTS: Individuals with schizophrenia who were not taking antipsychotic medications, as well as those taking antipsychotic medications, showed pervasive deficits across cognitive domains including reinforcement learning, processing speed, cognitive control, working memory, verbal learning and relational encoding and retrieval. Further, we found that chlorpromazine equivalency rates were significantly related to processing speed and working memory, while there were no significant relationships between anticholinergic load and performance on other tasks. CONCLUSIONS: These findings add to a body of literature suggesting that cognitive deficits are an enduring aspect of schizophrenia, present in those off antipsychotic medications as well as those taking antipsychotic medications.
BACKGROUND: Schizophrenia is a disorder characterized by pervasive deficits in cognitive functioning. However, few well-powered studies have examined the degree to which cognitive performance is impaired even among individuals with schizophrenia not currently on antipsychotic medications using a wide range of cognitive and reinforcement learning measures derived from cognitive neuroscience. Such research is particularly needed in the domain of reinforcement learning, given the central role of dopamine in reinforcement learning, and the potential impact of antipsychotic medications on dopamine function. METHODS: The present study sought to fill this gap by examining healthy controls (N = 75), unmedicated (N = 48) and medicated (N = 148) individuals with schizophrenia. Participants were recruited across five sites as part of the CNTRaCS Consortium to complete tasks assessing processing speed, cognitive control, working memory, verbal learning, relational encoding and retrieval, visual integration and reinforcement learning. RESULTS: Individuals with schizophrenia who were not taking antipsychotic medications, as well as those taking antipsychotic medications, showed pervasive deficits across cognitive domains including reinforcement learning, processing speed, cognitive control, working memory, verbal learning and relational encoding and retrieval. Further, we found that chlorpromazine equivalency rates were significantly related to processing speed and working memory, while there were no significant relationships between anticholinergic load and performance on other tasks. CONCLUSIONS: These findings add to a body of literature suggesting that cognitive deficits are an enduring aspect of schizophrenia, present in those off antipsychotic medications as well as those taking antipsychotic medications.
Authors: Alfredo Spagna; Yi Dong; Melissa-Ann Mackie; Ming Li; Philip D Harvey; Yanghua Tian; Kai Wang; Jin Fan Journal: Schizophr Res Date: 2015-08-20 Impact factor: 4.939
Authors: Georg Juckel; Florian Schlagenhauf; Michael Koslowski; Torsten Wüstenberg; Arno Villringer; Brian Knutson; Jana Wrase; Andreas Heinz Journal: Neuroimage Date: 2005-09-01 Impact factor: 6.556
Authors: Richard S E Keefe; Terry E Goldberg; Philip D Harvey; James M Gold; Margaret P Poe; Leigh Coughenour Journal: Schizophr Res Date: 2004-06-01 Impact factor: 4.939
Authors: Richard S E Keefe; Robert M Bilder; Sonia M Davis; Philip D Harvey; Barton W Palmer; James M Gold; Herbert Y Meltzer; Michael F Green; George Capuano; T Scott Stroup; Joseph P McEvoy; Marvin S Swartz; Robert A Rosenheck; Diana O Perkins; Clarence E Davis; John K Hsiao; Jeffrey A Lieberman Journal: Arch Gen Psychiatry Date: 2007-06