title: Neural oscillations involved in self-referential processing.
abstract: Human adults remember better trait words that are referenced to the self than those referenced to others. To investigate whether non-phase-locked neural oscillations engage in the self-reference effect, we recorded electroencephalogram (EEG) from healthy adults during trait judgments of the self and a familiar other. The wavelet analysis was used to calculate non-phase-locked time-frequency power associated with encoding of trait adjectives referenced to the self or the familiar other at theta (5-7 Hz), alpha (8-13 Hz), beta (14-27 Hz) and gamma (28-40 Hz) bands. We found that, relative to other-referential traits, self-referential traits induced event-related synchronization of theta-band activity over the frontal area at 700-800 ms and of alpha-band activity over the central area at 400-600 ms. In contrast, event-related desynchronization associated with self-referential traits was observed in beta-band activity over the central-parietal area at 700-800 ms and in gamma-band activity over the fronto-central area at 500-600 ms. Moreover, valence of traits referenced to the self and self-relevance of traits respectively led to modulations of theta/alpha- and beta/gamma-band activity. Finally, event-related synchronization of frontal theta-band activity at 700-800 ms positively correlated with the self-reference effect observed during memory retrieval. Our results indicate that non-phase-locked neural activity is involved in self-reflexive thinking. In addition, low and high-frequency neural oscillations play different roles in emotional and cognitive aspects of self-reference processing.
authors.affiliation: Department of Psychology, Peking University, Beijing 100871, PR China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Mu
authors.forename: Shihui
authors.initials: S
authors.lastname: Han
mesh_terms: D000293:Adolescent; D000328:Adult; D000465:Algorithms; D001921:Brain / Q000502:physiology*; D003071:Cognition / Q000502:physiology; D003627:Data Interpretation, Statistical; D004569:Electroencephalography; D004644:Emotions; D005071:Evoked Potentials / Q000502:physiology; D005260:Female; D005625:Frontal Lobe / Q000502:physiology; D006801:Humans; D008297:Male; D011939:Mental Recall / Q000502:physiology; D010551:Personality; D011930:Reaction Time / Q000502:physiology; D021641:Recognition, Psychology / Q000502:physiology; D012649:Self Concept; D012938:Social Perception; D055815:Young Adult