title: Association of intracortical inhibition with social cognition deficits in schizophrenia: Findings from a transcranial magnetic stimulation study.
abstract: Abnormal cortical-inhibition has been hypothesized to underlie social-cognition deficits in schizophrenia. Studies using transcranial magnetic stimulation (TMS) as a neurophysiological probe have demonstrated cortical-inhibition deficits in this group. We compared TMS-measured short- and long-interval intracortical-inhibition (SICI & LICI) in antipsychotic-naïve (n=33) and medicated (n=21) schizophrenia patients and in healthy comparison subjects (n=45). We also studied the association between cortical-inhibition and social-cognition deficits in the patients. Antipsychotic-naïve patients had significant deficits in SICI (i.e., less inhibitory response). In this group, SICI had significant inverse correlations with emotion processing and a global social-cognition score. Impaired intracortical-inhibition may thus contribute to social-cognition deficits in schizophrenia.
authors.affiliation: Department of Psychiatry, National Institute of Mental Health & Neurosciences (NIMHANS), Bangalore, India. Electronic address: urvakhsh@gmail.com.
authors.forename: Urvakhsh Meherwan
authors.initials: UM
authors.lastname: Mehta
authors.affiliation: Department of Psychiatry, National Institute of Mental Health & Neurosciences (NIMHANS), Bangalore, India. Electronic address: jagatth@yahoo.com.
authors.forename: Jagadisha
authors.initials: J
authors.lastname: Thirthalli
authors.affiliation: Department of Psychiatry, National Institute of Mental Health & Neurosciences (NIMHANS), Bangalore, India. Electronic address: rakshathi_bsvrj@yahoo.co.in.
authors.forename: Rakshathi
authors.initials: R
authors.lastname: Basavaraju
authors.affiliation: Department of Psychiatry, National Institute of Mental Health & Neurosciences (NIMHANS), Bangalore, India. Electronic address: kalyanybg@yahoo.com.
authors.forename: Bangalore N
authors.initials: BN
authors.lastname: Gangadhar
mesh_terms: D014150:Antipsychotic Agents / Q000627:therapeutic use; D002540:Cerebral Cortex / Q000187:drug effects / Q000503:physiopathology*; D003071:Cognition / Q000187:drug effects / Q000502:physiology*; D006801:Humans; D016014:Linear Models; D009483:Neuropsychological Tests; D012559:Schizophrenia / Q000188:drug therapy / Q000503:physiopathology*; D012938:Social Perception; D013997:Time Factors; D050781:Transcranial Magnetic Stimulation / Q000379:methods*
chemical_list: D014150:Antipsychotic Agents
keywords: Antipsychotics; Cortical inhibition; GABA; Neurobiology; Psychosis; Social cognition