Individual differences in affect dynamics during social situations: Insights from self-reported feelings and facial expressions

Social anxiety represents a significant burden to well-being and is characterized by enhanced negative affect in social situations. Affective processes in anxiety are usually investigated as a single response that represents the overall magnitude of affect elicited by an event. However, social events and the emotions that they elicit unfold over time. Importantly, individual differences in temporal dynamics of affect within fear-relevant situations might explain differences in social anxiety symptoms. The first aim of this study was to develop a paradigm to quantify individual differences in within-situation affect dynamics. The second aim was to test whether affect dynamics were associated with social anxiety symptoms. 84 young adults with low to high social anxiety symptoms viewed movie clips of negative, positive, and neutral social situations. They continuously rated their affect while viewing the scenes, and we measured their negative and positive facial expressions over time with facial electromyography (fEMG). Consequently, we could quantify subjective and expressed affect dynamics in terms of intensity, variability, instability, and inertia. Our results showed that affect dynamics unfolded on the timescale of seconds and differed between positive, negative, and neutral situations. Crucially, individuals differed in subjective and expressed dynamics even when viewing the exact same situation. In contrast to our expectations, only intensity but no other affect dynamics was associated with social anxiety. We argue that for comprehensive insights into the affective processes that underlie social anxiety, future research should investigate affect dynamics within fear-relevant situations on short timescales and distinguish between different types of anxiety.