Fig. 3.
D-cycloserine potentiates extinction when the extinction session is 3 hr but not 1 hr long. Discriminated responding on the active (open symbols) and inactive (filled symbols) levers was compared across experimental conditions. a, Saline injection prior to 1 hr extinction (N=7). b, DCS injection prior to 1 hr extinction (N=8). c, Saline injection prior to 3 hr extinction (N=7). d, DCS injection prior to 1 hr extinction (N=8). DCS had no effect upon the acquisition of discriminated responding with conditioned reinforcement with the 1-hr extinction session, but did retard acquisition with the 3-hr session. Data presented as mean ± SEM.