title: Failure to use corollary discharge to remap visual target locations is associated with psychotic symptom severity in schizophrenia.
abstract: Corollary discharge (CD) refers to "copies" of motor signals sent to sensory areas, allowing prediction of future sensory states. They enable the putative mechanisms supporting the distinction between self-generated and externally generated sensations. Accordingly, many authors have suggested that disturbed CD engenders psychotic symptoms of schizophrenia, which are characterized by agency distortions. CD also supports perceived visual stability across saccadic eye movements and is used to predict the postsaccadic retinal coordinates of visual stimuli, a process called remapping. We tested whether schizophrenia patients (SZP) show remapping disturbances as evidenced by systematic transsaccadic mislocalizations of visual targets. SZP and healthy controls (HC) performed a task in which a saccadic target disappeared upon saccade initiation and, after a brief delay, reappeared at a horizontally displaced position. HC judged the direction of this displacement accurately, despite spatial errors in saccade landing site, indicating that their comparison of the actual to predicted postsaccadic target location relied on accurate CD. SZP performed worse and relied more on saccade landing site as a proxy for the presaccadic target, consistent with disturbed CD. This remapping failure was strongest in patients with more severe psychotic symptoms, consistent with the theoretical link between disturbed CD and phenomenological experiences in schizophrenia.
authors.affiliation: Department of Psychiatry, University Medical Center, Utrecht, The Netherlands; Department of Psychiatry, Psychosomatic Medicine and Psychotherapy, University Hospital Frankfurt, Goethe University, Frankfurt am Main, Germany.
authors.forename: Lara
authors.initials: L
authors.lastname: Rösler
authors.affiliation: Bernstein Center for Computational Neuroscience and Department of Psychology, Humboldt University, Berlin, Germany;
authors.forename: Martin
authors.initials: M
authors.lastname: Rolfs
authors.affiliation: Department of Experimental Psychology, Helmholtz Institute, Utrecht University, Utrecht, The Netherlands; and.
authors.forename: Stefan
authors.initials: S
authors.lastname: van der Stigchel
authors.affiliation: Department of Psychiatry, University Medical Center, Utrecht, The Netherlands;
authors.forename: Sebastiaan F W
authors.initials: SF
authors.lastname: Neggers
authors.affiliation: Department of Psychiatry, University Medical Center, Utrecht, The Netherlands;
authors.forename: Wiepke
authors.initials: W
authors.lastname: Cahn
authors.affiliation: Department of Psychiatry, University Medical Center, Utrecht, The Netherlands;
authors.forename: René S
authors.initials: RS
authors.lastname: Kahn
authors.affiliation: Department of Psychiatry, University Medical Center, Utrecht, The Netherlands; thakka11@msu.edu.
authors.forename: Katharine N
authors.identifier: http://orcid.org/0000-0002-0026-2030
authors.initials: KN
authors.lastname: Thakkar
mesh_terms: D000328:Adult; D014150:Antipsychotic Agents / Q000627:therapeutic use; D001696:Biomechanical Phenomena; D005260:Female; D006801:Humans; D007600:Judgment; D008137:Longitudinal Studies; D008297:Male; D009483:Neuropsychological Tests; D010775:Photic Stimulation; D011569:Psychiatric Status Rating Scales; D012438:Saccades; D012559:Schizophrenia / Q000188:drug therapy / Q000503:physiopathology*; D012565:Schizophrenic Psychology; D013028:Space Perception
chemical_list: D014150:Antipsychotic Agents
keywords: corollary discharge; efference copy; remapping; saccadic eye movements; schizophrenia