title: Reward-dependent modulation of working memory is associated with negative symptoms in schizophrenia.
abstract: The negative symptoms of schizophrenia have been associated with altered neural activity during both reward processing and cognitive processing. Even though increasing evidence suggests a strong interaction between these two domains, it has not been studied in relation to negative symptoms. To elucidate neural mechanisms of the reward-cognition interaction, we applied a letter variant of the n-back working memory task and varied the financial incentives for performance. In the interaction contrast, we found a significantly activated cluster in the rostral anterior cingulate cortex (ACC), the middle frontal gyrus, and the bilateral superior frontal gyrus. The interaction did not differ significantly between the patient group and a healthy control group, suggesting that patients with schizophrenia are on average able to integrate reward information and utilize this information to maximize cognitive performance. However within the patient group, we found a significant inverse correlation of ACC activity with the factor diminished expression. This finding is consistent with the model that a lack of available cognitive resources leads to diminished expression. We therefore argue that patients with diminished expression have difficulties in recruiting additional cognitive resources (as implemented in the ACC) in response to an anticipated reward. Due to this lack of cognitive resources, less processing capacity is available for effective expression, resulting in diminished expressive behavior.
authors.affiliation: Department of Psychiatry, Psychotherapy and Psychosomatics, Psychiatric Hospital, University of Zurich, Lenggstrasse 31, 8032 Zurich, Switzerland; Laboratory for Social and Neural Systems Research, Department of Economics, University of Zurich, Bluemlisalpstrasse 10, 8006 Zurich, Switzerland. Electronic address: oliver.hager@econ.uzh.ch.
authors.forename: Oliver M
authors.initials: OM
authors.lastname: Hager
authors.affiliation: Department of Psychiatry, Psychotherapy and Psychosomatics, Psychiatric Hospital, University of Zurich, Lenggstrasse 31, 8032 Zurich, Switzerland.
authors.forename: Matthias
authors.initials: M
authors.lastname: Kirschner
authors.affiliation: Department of Psychiatry, Psychotherapy and Psychosomatics, Psychiatric Hospital, University of Zurich, Lenggstrasse 31, 8032 Zurich, Switzerland.
authors.forename: Martin
authors.initials: M
authors.lastname: Bischof
authors.affiliation: Department of Psychiatry, Psychotherapy and Psychosomatics, Psychiatric Hospital, University of Zurich, Lenggstrasse 31, 8032 Zurich, Switzerland; Laboratory for Social and Neural Systems Research, Department of Economics, University of Zurich, Bluemlisalpstrasse 10, 8006 Zurich, Switzerland.
authors.forename: Matthias N
authors.initials: MN
authors.lastname: Hartmann-Riemer
authors.affiliation: Department of Psychiatry, Psychotherapy and Psychosomatics, Psychiatric Hospital, University of Zurich, Lenggstrasse 31, 8032 Zurich, Switzerland.
authors.forename: Agne
authors.initials: A
authors.lastname: Kluge
authors.affiliation: Department of Psychiatry, Psychotherapy and Psychosomatics, Psychiatric Hospital, University of Zurich, Lenggstrasse 31, 8032 Zurich, Switzerland; Neuroscience Center Zurich, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland; Zurich Center for Integrative Human Physiology, Winterthurerstrasse 190, 8057 Zurich, Switzerland.
authors.forename: Erich
authors.initials: E
authors.lastname: Seifritz
authors.affiliation: Laboratory for Social and Neural Systems Research, Department of Economics, University of Zurich, Bluemlisalpstrasse 10, 8006 Zurich, Switzerland; Neuroscience Center Zurich, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland; Zurich Center for Integrative Human Physiology, Winterthurerstrasse 190, 8057 Zurich, Switzerland.
authors.forename: Philippe N
authors.initials: PN
authors.lastname: Tobler
authors.affiliation: Department of Psychiatry, Psychotherapy and Psychosomatics, Psychiatric Hospital, University of Zurich, Lenggstrasse 31, 8032 Zurich, Switzerland; Neuroscience Center Zurich, University of Zurich, Winterthurerstrasse 190, 8057 Zurich, Switzerland; Zurich Center for Integrative Human Physiology, Winterthurerstrasse 190, 8057 Zurich, Switzerland.
authors.forename: Stefan
authors.initials: S
authors.lastname: Kaiser
mesh_terms: D000328:Adult; D059031:Anticipation, Psychological / Q000502:physiology; D001921:Brain / Q000503:physiopathology*; D001931:Brain Mapping; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D008570:Memory, Short-Term / Q000502:physiology*; D009483:Neuropsychological Tests; D011569:Psychiatric Status Rating Scales; D011618:Psychotic Disorders / Q000503:physiopathology* / Q000523:psychology; D012201:Reward; D012559:Schizophrenia / Q000503:physiopathology*; D012565:Schizophrenic Psychology
keywords: Anterior cingulate cortex; Apathy; Diminished expression; Emotion–cognition interaction; Reward anticipation