Imagery-Enhanced CBGT Elicits Heart Rate Variability Changes in Social Anxiety Disorder

Patients with social anxiety disorder who were referred to a specialist mental health service in Australia between 2016 and 2019 were recruited for this randomized controlled trial.

In social anxiety disorder (SAD), imagery-enhanced cognitive behavioral group therapy (IE-CBGT) was found to increase median heart rate interval greater than verbal-based cognitive behavioral group therapy (VB-CBGT). These findings were published in Behaviour Research and Therapy.

Patients (N=107) with SAD who were referred to a specialist mental health service in Australia between 2016 and 2019 were recruited for this randomized controlled trial. Participants were randomized to receive 12 2-hour weekly group IE-CBGT (n=53) or VB-CBGT (n=54) sessions. The interventions employed cognitive restructuring techniques with no overt focus on imagery (VB-CBGT) or engaging in mental imagery (IE-CBGT). The primary outcomes were the change in skin conductance and heart rate variability during the trier social stress test (TSST) pre- and postintervention.

A total of 19 participants in both groups were lost to follow-up. Individuals in the IE-CBGT cohort who were lost had significantly higher baseline root mean-square successive difference of normal heartbeat intervals (β, 11.04; 95% CI, 0.83-21.24; P =.034).

No significant changes to skin conductance were observed during the preparation, speech, or social interaction phases of the TSST at 1- and 6-month follow-ups in either group.

For heart rate variability, however, median heart rate intervals were significantly higher among the IE-CBGT cohort at 1 month compared with the VB-CBGT recipients (mean difference [MD], 58.20; 95% CI, 21.15-95.24 P <.005). A similar trend was observed at 6 months (MD, 58.93; 95% CI, 26.66-91.19; P <.001).

The trend in heart rate changes in the IE-CBGT cohort was not due to elevated heart rate during the social stress, but instead to a lower resting heart rate. These trends likely indicated a greater reactivity between rest and social stress following the intervention.

At 6 months, the reduction in median resting heart rate was larger during the TSST preparation (MD, 48.86; 95% CI, 25.11-72.61; P <.001), social interaction (MD, 52.51; 95% CI, 25.93-79.08; P <.001), and speech (MD, 30.30; 95% CI, 5.23-55.37; P =.02) phases of the test in the IE-CBGT cohort.

This study may have been limited by not evaluating anxiety levels during the TSST.

“These findings provide robust support to theories positioning imagery as central in eliciting emotion and promoting therapeutic gain in SAD. Recent work has overviewed the important contribution that visceral signaling, particularly heart rate variability, plays in shaping brain dynamics and cognition, thus highlighting the importance of incorporating psychophysiological metrics in future studies attempting to establish links between cognition, neurobiology, and autonomic functioning,” concluded the study authors.


McEvoy PM, Hyett MP, Johnson AR, et al. Impacts of imagery-enhanced versus verbally-based cognitive behavioral group therapy on psychophysiological parameters in social anxiety disorder: Results from a randomized-controlled trial. Behav Res Ther. 2022;155:104131. doi:10.1016/j.brat.2022.104131