title: Some markers of mirroring appear intact in schizophrenia: evidence from mu suppression.
abstract: Although schizophrenia is associated with impairments in social cognition, the scope and neural correlates of these disturbances are largely unknown. In this study, we investigated whether schizophrenia patients show impaired functioning of the mirror neuron system (MNS), as indexed by electroencephalographic (EEG) mu (8-13 Hz) suppression, a hypothesized biomarker of MNS activity that is sensitive to the degree of social interaction depicted in visual stimuli. A total of 32 outpatients and 26 healthy controls completed an EEG paradigm that included six action observation or execution conditions that differed in their degrees of social interaction. Participants also completed a validated empathy questionnaire. Across both groups, we found a significant linear increase in mu suppression across the conditions involving greater levels of social engagement and interaction, but no significant group or interaction effects. Patients self-reported diminished empathic concern and perspective taking, which showed some moderate relations to mu suppression levels. Thus, the schizophrenia group showed generally intact modulation of MNS functioning at the electrophysiological level, despite self-reporting empathic disturbances. The disturbances commonly seen on self-report, performance, and neuroimaging measures of mentalizing in schizophrenia may largely reflect difficulties with higher-level inferential processes about others' emotions, rather than a basic incapacity to share in these experiences.
authors.affiliation: VA Greater Los Angeles Healthcare System, University of California, MIRECC 210A, Bldg. 210, 11301 Wilshire Blvd, Los Angeles, CA, 90073, USA, horan@ucla.edu.
authors.forename: William P
authors.initials: WP
authors.lastname: Horan
authors.forename: Jaime A
authors.initials: JA
authors.lastname: Pineda
authors.forename: Jonathan K
authors.initials: JK
authors.lastname: Wynn
authors.forename: Marco
authors.initials: M
authors.lastname: Iacoboni
authors.forename: Michael F
authors.initials: MF
authors.lastname: Green
mesh_terms: D000293:Adolescent; D000328:Adult; D000704:Analysis of Variance; D003072:Cognition Disorders / Q000209:etiology*; D004569:Electroencephalography; D004641:Emigration and Immigration; D004645:Empathy / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D011569:Psychiatric Status Rating Scales; D011597:Psychomotor Performance / Q000502:physiology*; D012559:Schizophrenia / Q000150:complications*; D012565:Schizophrenic Psychology; D012938:Social Perception; D055815:Young Adult