title: Altered sense of agency in schizophrenia and the putative psychotic prodrome.
abstract: The mechanisms underlying distortions in sense of agency, i.e. the experience of controlling one's own actions and their consequences, in schizophrenia are not fully understood and have barely been investigated in patients classified as being in a putative psychotic prodrome. This study aims to expound the contribution of early and late illness-related processes. Thirty schizophrenia patients, 30 putatively prodromal patients and 30 healthy controls were instructed to reproduce a computer-generated series of drum sounds on a drum pad. While tapping, subjects heard either their self-produced tones or a computer-controlled reproduction of the drum tone series that used either exactly the same, an accelerated or decelerated tempo. Subjects had to determine the source of agency. Results show similar significant impairments in assigning the source of agency under ambiguous conditions in schizophrenia and putatively prodromal patients and an exaggerated self-attribution bias, both of which were significantly correlated with increased (ego-)psychopathology. Patient groups, however, benefited significantly more than controls from additional sensorimotor cues to agency. Sensorimotor input seems to be a compensatory mechanism involved in correctly attributing agency. We deduce that altered awareness of agency may hold promise as an additional risk factor for psychosis.
authors.affiliation: The Zucker Hillside Hospital, North Shore - Long Island Jewish Health System, Glen Oaks, NY, USA. mhauser@nshs.edu
authors.forename: Marta
authors.initials: M
authors.lastname: Hauser
authors.forename: Guenther
authors.initials: G
authors.lastname: Knoblich
authors.forename: Bruno H
authors.initials: BH
authors.lastname: Repp
authors.forename: Marion
authors.initials: M
authors.lastname: Lautenschlager
authors.forename: Juergen
authors.initials: J
authors.lastname: Gallinat
authors.forename: Andreas
authors.initials: A
authors.lastname: Heinz
authors.forename: Martin
authors.initials: M
authors.lastname: Voss
mesh_terms: D000161:Acoustic Stimulation; D000328:Adult; D001308:Auditory Perceptual Disorders / Q000209:etiology*; D001364:Awareness; D015982:Bias; D003463:Cues; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D011569:Psychiatric Status Rating Scales; D011594:Psychometrics; D011618:Psychotic Disorders / Q000150:complications* / Q000523:psychology*; D012559:Schizophrenia / Q000150:complications*; D012565:Schizophrenic Psychology; D012680:Sensitivity and Specificity; D017603:Signal Detection, Psychological; D055815:Young Adult