Randomised, triple-blind Phase I factorial trial (n=108 planned) testing whether adjunctive taVNS enhances the long-term beneficial effects of a single open-label 25 mg psilocybin dose in medically healthy adults with modest reductions in wellbeing.
A factorial, randomized study in healthy volunteers comparing combinations of active or sham transcutaneous auricular vagus nerve stimulation (taVNS) delivered before and after a single open-label 25 mg psilocybin dose to examine whether taVNS enhances retention of insights and long-term beneficial behavioural effects.
Participants receive 2–4 hours of preparatory support, a 6–8 hour psilocybin dosing session, and integration sessions at 1 day and ~1 week post-dosing; taVNS (active or sham) is delivered 20 minutes twice daily for 7 days according to randomisation.
Sham taVNS for 7 days pre-psilocybin; active taVNS twice daily for 7 days post-psilocybin.
Single open-label 25 mg psilocybin capsule administered in set-and-setting.
Sham taVNS twice daily for 7 days prior to dosing (pre); active taVNS 20 min twice daily for 7 days post-dosing (post).
Sham taVNS twice daily for 7 days pre- and post-psilocybin.
Single open-label 25 mg psilocybin capsule.
Sham taVNS 20 min twice daily for 7 days pre- and post-dosing.
Sham taVNS twice daily for 7 days pre-psilocybin; psychosocial support alone post-psilocybin (integration sessions).
Single open-label 25 mg psilocybin capsule.
Sham taVNS twice daily for 7 days pre-dosing; post-dosing receive psychosocial support (integration at 1 day and ~1 week) instead of active taVNS.
Psychosocial support: SaS framework; integration sessions 1 day and 9 days post-dosing (1 hour each).
Active taVNS twice daily for 7 days pre-psilocybin; sham taVNS twice daily for 7 days post-psilocybin.
Single open-label 25 mg psilocybin capsule.
Active taVNS 20 min twice daily for 7 days pre-dosing; sham taVNS 20 min twice daily for 7 days post-dosing.