The current data also suggest that expectancy or motivational processes might play a role in post-error implementation of control, particularly in the performance adjustment process. Specifically, the control group did not show a typical compatibility effect in the FSW on post-error trials, and although planned contrasts indicated significant expectancy as well as pharmacological effects in both the N2 and FSW components, the control group’s post-error FSW responses were more similar to those of the alcohol group than the placebo group, suggesting the possibility that this aspect of cognitive control is more sensitive to expectancy-related than to pharmacological effects of alcohol. Findings from a number of recent studies are consistent with the idea that participants who consume a placebo engage greater cognitive resources and (sometimes) behaviorally outperform those in the control group (e.g., Bartholow et al., 2012; Fillmore, Mulvihill, & Vogel-Sprott, 1994; Fillmore & Vogel-Sprott, 1995; Saults, Cowan, Sher, & Moreno, 2007; Williams, Goldman, & Williams, 1981). Several theorists have posited that this effect stems from placebo participants anticipating cognitive impairment from alcohol and therefore exerting more effort during cognitive tasks compared to control participants (e.g., Fillmore & Blackburn, 2002; Marczinski & Fillmore, 2005; Williams et al., 1981).
