Figure 2

Results of fear-potentiated startle (FPS) response. The contextual threat conditioning procedure resulted in acquisition, retention and extinction of threat-related FPS responses, but an isolated reminder before extinction did not prevent the return of FPS responses on the following day. Bars reflect mean t-scored startle responses during the early (first half of trials) and late phase (second half of trials) of each task for the threat (CTX+, red) and safe context (CTX−, blue) and neutral hallway (green) for the Reminder-Extinction group (solid bars) and Extinction group (open bars). Error bars = s.e.m., adjacent dots represent jittered individual data-points. *p < 0.05, **p < 0.01, ***p < 0.001. (a) Both groups acquired comparable differential contextual threat conditioned FPS responses. On day 2, both groups showed comparable extinction of FPS responses, where differential FPS responses were fully extinguished at the end of the task. (b) Both groups showed comparable generalized spontaneous recovery of FPS responses to both the CTX+ and CTX− during the early phase of the spontaneous recovery test. Although the initial recovery is generalized, FPS responses in the CTX+ showed slower re-extinction, indicating differential retention of the conditioned FPS responses. (c) Following two unsignaled shocks, FPS responses showed evidence for reinstatement as differential responses to the CTX+ and CTX− are greater during the early phase as compared to the late phase.