title: Magnetoencephalographic evidence of early right hemisphere overactivation during metaphor comprehension in schizophrenia.
abstract: Whereas language processing in neurotypical brains is left lateralized, individuals with schizophrenia (SZ) display a bilateral or reversed pattern of lateralization. We used MEG to investigate the implications of this atypicality on fine (left hemisphere) versus coarse (right hemisphere) semantic processing. Ten SZ and 14 controls were presented with fine (conventional metaphor, literal, and unrelated expressions) and coarse (novel metaphor) linguistic stimuli. Results showed greater activation of the right hemisphere for novel metaphors and greater bilateral activation for unrelated expressions at the M170 window in SZ. Moreover, at the M350, SZ showed reduced bilateral activation. We conclude that SZ are overreliant on early-stage coarse semantic processing. As a result, they jump too quickly to remote conclusions, with limited control over the meanings they form. This may explain one of the core symptoms of the disorder-loose associations.
authors.affiliation: Department of Psychology, Bar-Ilan University, Ramat-Gan, Israel.|Gonda Brain Research Center, Bar-Ilan University, Ramat-Gan, Israel.
authors.forename: Maor
authors.initials: M
authors.lastname: Zeev-Wolf
authors.affiliation: Department of Psychology, Bar-Ilan University, Ramat-Gan, Israel.|Gonda Brain Research Center, Bar-Ilan University, Ramat-Gan, Israel.
authors.forename: Miriam
authors.initials: M
authors.lastname: Faust
authors.affiliation: Emotion-Cognition Research Center, The Shalvata Mental Health Care Center, Hod-Hasharon, Israel.|Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv, Israel.
authors.forename: Yechiel
authors.initials: Y
authors.lastname: Levkovitz
authors.affiliation: Gonda Brain Research Center, Bar-Ilan University, Ramat-Gan, Israel.
authors.forename: Yuval
authors.initials: Y
authors.lastname: Harpaz
authors.affiliation: Department of Psychology, Bar-Ilan University, Ramat-Gan, Israel.|Gonda Brain Research Center, Bar-Ilan University, Ramat-Gan, Israel.
authors.forename: Abraham
authors.initials: A
authors.lastname: Goldstein
mesh_terms: D000328:Adult; D001921:Brain / Q000503:physiopathology*; D001931:Brain Mapping; D032882:Comprehension / Q000502:physiology*; D005260:Female; D007839:Functional Laterality / Q000502:physiology*; D006801:Humans; D015225:Magnetoencephalography; D008297:Male; D019365:Metaphor; D008875:Middle Aged; D011930:Reaction Time / Q000502:physiology; D012559:Schizophrenia / Q000503:physiopathology*; D012565:Schizophrenic Psychology; D055815:Young Adult
keywords: M170; Magnetoencephalography; Metaphor comprehension; Schizophrenia; Semantic processing