Breath
Bring it down a notch first.
A 5-minute breath protocol activates parasympathetic tone, increases heart-rate variability, and clears acute autonomic noise. Use it before talking to anyone — you're starting from a steadier baseline. See research §4 for the clinical evidence base.
Ready
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Why these protocols
At ~5.5 breaths per minute (~0.1 Hz), respiratory and cardiac rhythms synchronize. Baroreflex amplification follows. HRV climbs measurably within 5-10 minutes. The autonomic shift is real and clinically documented.
Box breathing is what U.S. Navy SEALs use during BUD/S. 4-7-8 has accumulated evidence in anxiety and insomnia populations. Different mechanism, similar destination — slow, controlled, vagal.
Phase II — biofeedback loop
Phase I demonstration: visual + paced. Phase II proposed: wrist-worn HRV biofeedback channel via Apple Watch + QuietPulse (the PI's shipping breath app, already on the App Store). The system tells you the breathing is actually working.
Tan & Dao (2011) — 8-session HRVB on combat-related PTSD veterans showed significant reductions on both CAPS and PCL. Phase I work plan includes a feasibility extension to acute crisis context. Citations.
If breathing makes things feel worse rather than better — and that does happen for some trauma populations — stop and reach out to your peer ring or the Veterans Crisis Line (988 then press 1). Breath protocols are not appropriate for every nervous system in every state.