FV 14 Dynamic modulation of vigilance states during affective stimulation

Abstract

Background To investigate the interplay between affective information processing and functional brain states, differences in arousal regulation after stimulation with affective narratives were investigated. Based on EEG acquisitions at resting state, it is possible to differentiate stages of wakefulness regulation. The temporal evolution of these vigilance stages sheds light on individual variations in arousal level in reaction to preceding affective stimulation ( Olbrich et al., 2009 ). Methods Resting state EEG was recorded from eighteen healthy subjects for 10 min each with eyes closed: first at baseline and then after passive listening to three emotional narratives about experiences in early childhood of strangers (securely attached, insecure-dismissing, insecure-preoccupied) ( Borchardt et al., 2015 ). Using the VIGALL 2.0 algorithm, vigilance stages (high: A1, A2, A3, low: B2/3) in consecutive EEG segments (duration: 2.4 s) were classified and their dynamic profile was analyszed ( Sander et al., 2015 ). Additionally, the Temperament and Character Inventory (TCI) was assessed ( Cloninger et al., 1993 ). Results At baseline, the percentage of subjects in low vigilance stages was continuously high and stable over time, while in conditions after emotional stimulation the percentage of subjects was first highest in high vigilance stages but quickly decreased over time. A difference between narrative conditions was revealed in the insecure-dismissing condition, in which the decrease of the percentage of subjects in high vigilance stages was highest compared to the other two conditions. Analyzing dynamics of vigilance stages, only in the insecure-dismissing condition, the number of EEG segments in high vigilance stages in the first 160 s (interval 1) was significantly higher compared to the last 160 s (interval 4) after normalization to the subject-specific baseline level (p = 0.008). In a subgroup of the participants (N = 14), we found a significant, strong negative correlation (r = −0.82, p = 0.0003) between individual dynamic of slope in high vigilance stages at baseline and harm avoidance, a temperament trait of personality, whose characteristics are elevated tiredness, weakness, and a prolonged recovery after emotional stress. Discussion At resting state, a continuous decrease of vigilance is a physiological finding ( Olbrich et al., 2009 ). So far, an effect of preceding auditory stimulation with affective content on regulation of wakefulness has not been investigated and provides evidence for dynamic influences of emotions and mood on brain states ( Borchardt et al., 2015 , Bola and Borchardt, 2016 ).