Time-to-Regulation
Concept
The terminal objective (capacity for evaluative access) requires a way to evaluate whether the system is working. The conceptual origin: how long does it take this person, in this state, to return to a state where they can use help? That duration is the fundamental constraint on intervention design. Everything else -- what technique, what content, what modality -- is downstream of that.
Multi-timescale complexity
Time-to-regulation is not a single number. The systems that constitute "state" operate on different timescales with different recovery trajectories:
- Dynamic network connectivity: Recovers in seconds when stressor removed
- Catecholamine levels: Normalize over minutes
- Cortisol: 20-60 minutes to return to baseline after social-evaluative stress; longer after uncontrollable stressors (Dickerson & Kemeny 2004)
- Dorsal raphe sensitization: Persists for days
- Prefrontal plasticity changes: Unfold over weeks
"Regulation" of which system, on which timescale, is the rate-limiting factor for this person right now? That question cannot be answered without tracking multiple systems simultaneously.
Candidate metrics
Distributional measures are candidates for evaluation:
- Median TTR
- Tail TTR (worst-case recovery times)
- Frequency of regime excursions
But which system's recovery trajectory to track, and how to identify the rate-limiting factor for a given person at a given time, are open questions that depend on the plant model.
Related constraint
Time-to-service -- the latency from need to access -- is a separate constraint acknowledged but addressed separately under cost/access (see constraint: cost-access.md).