title: Contrast, motion, perceptual integration, and neurocognition in schizophrenia: the role of fragile-X related mechanisms.
abstract: Recent studies demonstrated a reduced expression of Fragile X Mental Retardation Protein (FMRP), an RNA binding protein and translation regulator, in the brain and peripheral lymphocytes of patients with schizophrenia. Low FMRP levels may be related to impaired neurodevelopmental processes and synaptic plasticity. Here, we studied the relationship between peripheral FMRP level, visual perception (contrast sensitivity, perceptual integration, motion/form perception), and neuropsychological functions in schizophrenia as measured with the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS). Results revealed that patients with schizophrenia displayed lower FMRP levels in peripheral lymphocytes as compared to control individuals. We found significant correlations between FMRP levels and contrast sensitivity at low spatial and high temporal frequencies, perceptual integration, and motion perception. The relationship between FMRP level and neuropsychological functions was less pronounced than that seen in the case of visual perception, with the greatest effect for RBANS attention. FMRP level was not related to contrast sensitivity at high spatial and low temporal frequencies and form perception. This pattern of data is reminiscent to that observed in patients with Fragile X Syndrome (FXS). These results suggest that FMRP may be implicated in the pathogenesis of schizophrenia, possibly via the regulation of neurodevelopment, plasticity, GABA-ergic, and glutamatergic neurotransmission.
authors.affiliation: Bács-Kiskun County Hospital, Psychiatry Center, Kecskemét, Hungary.
authors.forename: Oguz
authors.initials: O
authors.lastname: Kelemen
authors.forename: Tamás
authors.initials: T
authors.lastname: Kovács
authors.forename: Szabolcs
authors.initials: S
authors.lastname: Kéri
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000097:blood; D003072:Cognition Disorders / Q000097:blood* / Q000175:diagnosis / Q000453:epidemiology; D015350:Contrast Sensitivity / Q000502:physiology*; D005260:Female; D051860:Fragile X Messenger Ribonucleoprotein 1 / Q000097:blood*; D005600:Fragile X Syndrome / Q000097:blood / Q000175:diagnosis / Q000453:epidemiology; D006801:Humans; D008214:Lymphocytes / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D009039:Motion Perception / Q000502:physiology*; D010775:Photic Stimulation / Q000379:methods*; D012559:Schizophrenia / Q000097:blood* / Q000453:epidemiology
chemical_list: D015415:Biomarkers; D051860:Fragile X Messenger Ribonucleoprotein 1
keywords: ANOVA; FMRP; FXS; Fragile X Syndrome; GABA; HSD; M; Neurocognition; P; PANSS; Positive and Negative Syndrome Scale; RBANS; Repeatable Battery for the Assessment of Neuropsychological Status; SF; Schizophrenia; TF; Visual perception; analysis of variance; fragile X mental retardation protein; fragile x syndrome; gamma-aminobutyric acid; honestly significant difference; magnocellular; parvocellular; spatial frequency; temporal frequency