TABLE 2.

Summary of classification criteria, Post-trauma phenotype and test parameters for the RISP model.

Model	Pre-trauma behavior		Trauma	Post-trauma phenotype
	Acoustic Startle Response (ASR1)	Elevated Plus Maze (EPM)	Contextual Fear Conditioning (CFC) with foot shock	Fear Extinction Training (EXT)	Acoustic Startle Response (ASR2)
Resilient (RES) phenotype	Low ASR defined as Average ASR less than group average and six or more individual readings below group average	Low anxiety-like behavior measured as ≥3 entries into the open arms	Acute stress response (freezing) similar to SUS rats	RES rats exhibit unimpaired fear extinction (progressively lower freezing)	ASR 2 response that is the same or lower than ASR 1
Susceptible (SUS) phenotype	High ASR defined as Average ASR greater than group average and six or more individual readings above group average	Heightened anxiety-like behavior measured as ≤2 entries into the open arms	Acute stress response (freezing) similar to RES rats	SUS rats exhibit impaired fear extinction (slower extinction or days with re-bound freezing)	ASR 2 response that is the same or higher than ASR 1
Test parameters	3 min habituation followed by 15 trials with random inter-trial intervals (15–45 s) of 120 db white noise bursts	5 min exploration of EPM (77 cm above floor) under low light (0–6 lux) and low open arm ledge (1 cm)	3 min habituation to shock context followed by 2 × 1 mA shocks 30 s apart. 5 min total duration in box	5 days of 5 min exposure to shock context without any shock.	3 min Habituation followed by 15 trials with random inter-trial intervals (15–45 s) of 120 db white noise bursts