Schedule of Events | Symposia

State-anxiety modulates the relationship between interoception and spontaneous fluctuations in subjective arousal

Poster Session B - Sunday, March 30, 2025, 8:00 – 10:00 am EDT, Back Bay Ballroom/Republic Ballroom

David Braun¹ (db3566@drexel.edu), Lotus Shareef-Trudeau¹, Swetha Rao¹, Christine Chesebrough², Julia Kam³, Aaron Kucyi¹; ¹Drexel University, ²Feinstein Institutes for Medical Research, ³University of Calgary

Spontaneous thoughts have been associated with a variety of neural correlates, but the relationship between distinct features of ongoing mental experience and the brain’s sensitivity to bodily signals (i.e., interoception) remains largely unexplored. Given interoception’s key role in emotion, investigating its relationship to spontaneous thoughts may provide important insight into how subjective experiences like arousal and anxiety are regulated. We used EEG and ECG to measure the heartbeat evoked potential (HEP), a dynamic index of interoceptive processing, while 51 participants visually fixated on a static cross image and let their minds wander freely. At pseudo-random intervals, participants were asked to rate their level of arousal in the moment. This measure of subjective arousal was highly variable within and between individuals but was statistically unrelated to several markers of physiological arousal, including heart rate, heart rate variability, time on task, and EEG alpha power at posterior electrodes. A cluster-based permutation analysis revealed that the HEP magnitude was increased during high relative to low subjective arousal in a set of frontal electrodes during the 0.328 s – 0.364 s window after heartbeat onset (p = .016; cluster-forming threshold of p = .01; 1000 permutations). This effect was amplified in participants who scored higher in state anxiety (r = .36, p = .04). These HEP effects may reflect an adaptive mechanism whereby the brain responds to anxiety by modulating sensitivity to bodily signals to regulate the momentary, spontaneous experience of subjective arousal—a mechanism that may operate independently of fluctuations in physiological arousal.

Topic Area: THINKING: Other