Pre- and Post-treatment effects in the PTSD + group by experimental phase. For Acquisition (ACQ), there were significant main effects of Block, CS-Type, and a 2-way interaction of Block × CS type. For extinction training (EXT), there were main effects of Treatment, Block, CS type, and a Treatment × Block interaction. There were no observed effects of treatment on Habituation (HAB) and Late Acquisition (ACQ) phases but there was a significant treatment-related decrease in FPS during Early and Late Extinction. There was a Treatment effect on extinction Recall, with significant discrimination between CS+ and CS- observed only at Post-treatment in both groups. ** - p < 0.01; ***p < 0.001; TEPC = trauma exposed; Shading indicates the context for extinction training session that occurred 10 min after acquisition, and extinction recall that occurred in the same context 24 h later.