People tend to slow down after they make an
error. This phenomenon, generally referred to as post-error
slowing, has been hypothesized to reflect perceptual
distraction, time wasted on irrelevant processes, an a priori
bias against the response made in error, increased variability in a priori bias, or an increase in response caution.
Although the response caution interpretation has dominated
the empirical literature, little research has attempted to test
this interpretation in the context of a formal process model.
Here, we used the drift diffusion model to isolate and
identify the psychological processes responsible for posterror slowing. In a very large lexical decision data set, we
found that post-error slowing was associated with an
increase in response caution and—to a lesser extent—a
change in response bias. In the present data set, we found
no evidence that post-error slowing is caused by perceptual
distraction or time wasted on irrelevant processes. These
results support a response-monitoring account of post-error