Performance adjustment is the process whereby control is enhanced following the presence of conflict (e.g., Gratton, Coles, Sirevaag, Eriksen, & Donchin, 1988) or when control has failed and an error has occurred (e.g., Garavan, Ross, Murphy, Roche, & Stein, 2002; Rabbitt, 1966; Ridderinkhof, Ullsperger, Crone, & Nieuwenhuis, 2004; Ullsperger & von Cramen, 2006). In particular, the occurrence of errors should signal that the current implementation of control is insufficient and must be adjusted in order to maintain desirable performance (Yeung, Botvinick, & Cohen, 2004). One behavioral index of performance-based adjustments in cognitive control is the size of the CE following incorrect trials. If errors prompt an increase in control, the CE should be smaller following errors than following correct responses, as enhanced control should attenuate the difference in responses to compatible and incompatible trials. This kind of effect has been reported by numerous researchers (e.g., Burle, Passamai, Vidal, Bonnet, & Hasbroucq, 2002; Rabbitt & Vyas, 1970; Smith & Brewer, 1995). Using a flanker task, Ridderinkhof and colleagues (2002) tested whether alcohol impairs post-error adjustment, reporting that the magnitude of the
