Cognitive control over speeded actions: a common locus for micro- and macro-tradeoffs?

Cognitive control processes associated with long- and short-term adjustments of human behavior have attracted much interest recently. It is still unclear, however, whether the mechanisms underlying these adjustment share a common locus within the chain of S-R processing. In order to address this issue, the present study employed a speed-accuracy (SAT) instruction producing a macro-tradeoff, whereas micro-tradeoff was studied by means of post-error slowing in reaction time (RT). Participants performed either a spatially compatible or incompatible four stimuli-to-two response alternative choice RT task. Reliable variations in micro-and macro-tradeoff as well as effects of spatial compatibility were found in RT and error rate. Most importantly, post-error slowing was larger when instruction stressed accuracy rather than speed, an effect being independent of spatial compatibility. Because the influence of SAT instruction and post-error slowing on performance was strongest for response alternations, together, present findings suggest that the mechanisms underlying micro- and macro-tradeoffs have one common locus at the level of motor processing. Additional influences of macro-tradeoff on premotoric processing are likely