title: Deficit of inhibition motor control in untreated patients with schizophrenia: further support from visually guided saccade paradigms.
abstract: In addition to classical delusional, negative, and cognitive deficit, schizophrenia has consistently been associated with impairments in saccadic eye movements, e.g., an increased error rate in the antisaccade task. We hypothesized that a deficit in inhibitory control is a core defect in untreated patients with schizophrenia leading to impairment in different oculomotor paradigms. Ten drug-free or drug-naïve patients with schizophrenia were matched in age and gender to 11 healthy controls with no psychoactive substance use or abuse. They were explored using reflexive saccades with unpredictable targets with or without the gap procedure, predictive saccades and a fixation/distracter paradigm. Patients with schizophrenia displayed shorter latency in reflexive and predictive saccades. In the GAP condition, patients made more anticipatory saccades, fewer regular saccades, and had a shorter latency of express saccades than controls. In addition, patients had an increased error rate in the fixation/distracters task. Altogether, these results provide new evidence of reduced prefrontal inhibitory regulation of subcortical and brainstem systems involved in the control of saccades.
authors.affiliation: Université Paris Descartes, Faculté de médecine Paris Descartes, Paris, France.
authors.forename: Marie Odile
authors.initials: MO
authors.lastname: Krebs
authors.forename: Marie-Chantal
authors.initials: MC
authors.lastname: Bourdel
authors.forename: Zhor Rhamdane
authors.initials: ZR
authors.lastname: Cherif
authors.forename: Philippe
authors.initials: P
authors.lastname: Bouhours
authors.forename: Henri
authors.initials: H
authors.lastname: Lôo
authors.forename: Marie France
authors.initials: MF
authors.lastname: Poirier
authors.forename: Isabelle
authors.initials: I
authors.lastname: Amado
mesh_terms: D000328:Adult; D053483:Eye Movement Measurements; D005260:Female; D006801:Humans; D007266:Inhibition, Psychological; D008297:Male; D015999:Multivariate Analysis; D010775:Photic Stimulation; D011930:Reaction Time / Q000502:physiology; D012438:Saccades / Q000502:physiology*; D012559:Schizophrenia / Q000503:physiopathology*