Houtman, F. , Van der Borght, L. , Fias, W. & Notebaert, W.
Ghent University
It has been shown that people who are more sensitive for errors demonstrate a different reaction to errors. For example, adults with an obsessive-compulsive disorder show increased post-error slowing (Veale, Sahakian, Owen, & Marks, 1996). In the present study, we manipulated error sensitivity experimentally in an arrow flanker task. Participants were either rewarded for correct trials, or punished for error trials. Moreover, both the reward and the punishment groups were further divided in a high and low reward/punishment condition, resulting in 4 between-subjects conditions. Post-error slowing was observed in the punishment groups but not in the reward groups, indicating that more attention was directed to the errors in the punishment group, in line with the orienting account for post-error slowing (Notebaert et al., 2009). Interestingly, there was post-error accuracy decrease in all groups. This indicates that post-error slowing is not functional and does not improve performance and, more important, that post-error accuracy is dissociable from post-error speed. While reaction times on trial n depend on the amount of attention directed to the action outcome of trial n-1, accuracy on trial n is more directly correlated with accuracy on trial n-1.