The inhibition of imitative response tendencies

Recent neurocognitive studies show that perception and execution of actions are intimately linked. The mere observation of an action seems to evoke a tendency to execute that action. Since such imitative response tendencies a re not adaptive in many everyday situations imitative response tendencies u sually have to be inhibited. These inhibitory processes have never been inv estigated using brain imaging techniques. Former work on response inhibitio n and interference control has focused on paradigms such as the Stroop task or the go/no-go task. We have carried out an event-related functional magn etic resonance imaging study in order to investigate the cortical mechanism s underlying the inhibition of imitative responses. The experiment employs a simple response task in which subjects were instructed to execute predefi ned finger movements (tapping or lifting of the index finger) in response t o an observed congruent or incongruent finger movement (tapping or lifting) . A comparison of brain activation in incongruent and congruent trials reve aled strong activation in the dorsolateral prefrontal cortex (middle fronta l gyrus) and activation in the right frontopolar cortex and the right anter ior parietal cortex, as well as in the precuneus. These results support the assumption of prefrontal involvement in response inhibition and extend thi s assumption to a "new" class of prepotent responses, namely, to imitative actions. (C) 2001 Academic Press.