The authors tested the hypothesis that disengagement during intentional shifts between task sets is accompanied by inhibition of the previous task set ("backward inhibition") and predicted increased response times when shifting to a task set that had to be abandoned recently and, thus, suffers residual inhibition.
The results suggest that the domain of the cerebellar timing process is not limited to the motor system, but is employed by other perceptual and cognitive systems when temporally predictive computations are needed.
The results suggest that attentional and nonattentional learning operate independently, in parallel, do not share information, and represent sequential information in qualitatively different ways.
The authors theorize that 2 neurocognitive sequence-learning systems can be distinguished in serial reaction time experiments, one dorsal (parietal and supplementary motor cortex) and the other ventral (temporal and lateral prefrontal cortex), which are relevant to issues of attentional effects on learning.
Using the framework of equilibrium point theory of movement, it is discussed how a set switching deficit may also underlie clinical motor disturbances seen in Parkinson's disease.