Fear-antagonistic actions and safety behaviors in the treatment of acrophobia: A randomized controlled trial.

Exposure therapy effectively treats anxiety disorders, yet non-response and premature dropout motivate continued work on procedural enhancements. Fear-antagonistic actions, behaviors that directly oppose fear-driven action tendencies (e.g., walking briskly toward and leaning over a railing rather than standing back from the edge), can augment exposure, but performing them necessarily precludes safety behaviors. This study examined whether fear-antagonistic actions confer augmentation effects beyond safety behavior elimination alone. University students and community adults with long-standing, clinically significant fear of heights (N = 109; 68% female; mean age = 21.8 years) were randomly assigned to standard exposure (EXP; n = 32), exposure with safety behavior fading (EXP+SBF; n = 31), exposure with safety behavior fading plus fear-antagonistic actions (EXP+SBF+AA; n = 35), or waitlist control (WLC; n = 11). Peak fear during a behavioral approach test in a novel (generalization) context served as the pre-designated primary outcome. Both EXP + SBF + AA and EXP + SBF outperformed EXP on peak fear in the treatment and generalization contexts through 1-month follow-up, and all active conditions outperformed WLC. EXP + SBF + AA and EXP + SBF did not significantly differ on any primary or secondary outcome (all ps > .140). Bayes factors provided moderate evidence against differential change on the primary outcome (BF01 = 6.1), although equivalence tests could not exclude small-to-moderate differences. Marked reductions in height overestimation occurred for all active groups and were sustained at 1-month follow-up. Findings indicate that safety behavior elimination is the robust active ingredient driving augmentation effects; any incremental benefit of fear-antagonistic actions is likely small.