Effects of SB-334867 on performance during Go and Stop trials in the stop signal task. Effects of acute administration of the OxR1 receptor antagonist SB-334867 or its vehicle on (A) probability of correct Go trials, (B) median reaction time on correct Go trials (GoRT), (C) the ICV or intra-individual coefficient of variation [standard deviation GoRT/mean GoRT], (D) median movement time (MT), i.e. time between exit of the nosepoke port and a lever press on correct Go trials, (E) probability of failed Stop trials, (F) estimated stop-signal reaction time (SSRT), (G) probability of waiting errors during Stop trials and (H) percentage of trials with a nosepoke port exit during the hold period. For the baseline measurement, data from the training sessions immediately preceding the 3 test days was averaged. Error bars represent standard error of the mean, while open circles represent data from individual rats (N =21).