Figure 5.
Extinction training and retention in MDMA group by retainers and non-retainers: (a) within the MDMA group, retainers (Ret) demonstrated full retention of extinction training from the end of extinction training (EXT4) to the extinction retention test (RET) with no return of fear via spontaneous recovery. The non-retainers (Non-Ret) demonstrated spontaneous recovery from EXT4 to RET (significant block × group interaction, F(1,15) = 9.34, p = 0.008). (b) Scatterplot demonstrating that there were no retainers (Ret) in the placebo (PBO) group but there were significantly more retainers (n = 6) in the MDMA group (χ2 = 7.29, p = 0.007).
PBO = Placebo; MDMA = 3,4-methylenedioxymethamphetamine; EXT = extinction; RET = extinction retention; fear-potentiated startle = [mean startle magnitude to CS] – [mean startle magnitude to noise alone]; μV = microvolts.