Pursuit of interpersonal relationships : behavioral and brain response correlates of social acceptance and rejection

Abstract

Pursuing and building social connections is important for people’s well-being. However, the neural underpinnings of a range of decision-making behaviors and social interactions in the pursuit of social relationships remain unclear. To explore these behaviors and interactions, I designed three studies using a novel online speed dating task, along with the recording of brain activity using electroencephalogram (EEG) technology. In Study I, I explored the behavior and EEG responses of participants in the stages of decision-making, anticipation, and outcome evaluation in pursuit of romantic relationships. In Study II, I further explored how waiting time affects the outcome evaluation stage, as social feedback is not always immediate in social context. In Study III, I examined the effect of oxytocin on social rejection because the previous studies showed oxytocin to be a promising candidate for regulating social behavior and reducing negative emotions. The results show that, in Study I, participants exhibited more negative stimulus preceding negativity (SPN), when they waited for social evaluation from important compared to unimportant others. The largest reward positivity (RewP) was observed when participants received acceptance from important others and the greatest theta power was observed when participants received a rejection from important others. Furthermore, the burst of theta power was source-localized to the anterior cingulate cortex and frontal pole, which is related to physical pain processing. In Study II, the reduced RewP was observed for the feedback from unimportant others in the long wait condition. On the contrary, the increased RewP was observed for the feedback from important others in the long wait condition. In Study III, the oxytocin group showed significantly lower theta power than the placebo group when they received a social rejection. Also, the negative correlation between theta power and self-reported pleasantness ratings was found only in the placebo group, not in the oxytocin group. Taken together, my dissertation highlights the role of SPN, RewP, and theta oscillations in social relationship pursuit, reveals the effects of subjective preference and wait time on the processing of social feedback, and provides pharmacology-electrophysiological evidence that oxytocin alleviates social pain induced by social rejection.