Event-related synchronization of delta and beta oscillations reflects developmental changes in the processing of affective pictures during adolescence

Recent research has determined that affective pictures modulate event-related delta and beta oscillations in adults. However, it is unclear whether these brain oscillations reflect developmental changes in the processing of affective information during adolescence. EEG data were collected from 51 adolescents and 18 undergraduates as they viewed a total of 90 pictures. In the range of fast wave activities, event-related synchronization (ERS) in the beta band varied with emotional valence, indicating that beta ERS is indicative of early bottom-up processing of visual emotional stimuli. Adolescents at the age of 12 years exhibited more positive beta ERS amplitudes over posterior brain regions for positive versus neutral pictures compared to adolescents at the ages 14years, 16 years and in young adults; however, no age-related differences were found for negative versus neutral pictures. In the range of slow wave activities, delta ERSs and late positive potential (LPP) amplitudes exhibited affective modulation and decreased over anterior brain regions from between the age of 12 years and early adulthood. These slow wave activities (delta and LPPs) reflected top-down attention to the motivational relevance of the emotional stimuli. Taken together, these observations suggest that adolescents exhibit dissociable ERS patterns in the delta and beta bands during affective processing. Furthermore, adolescents undergo age-dependent changes in oscillatory brain reorganization. Our results should be useful to researchers interested in affective processing during adolescence. (C) 2013 Elsevier B.V. All rights reserved.