Stroking me softly: Body-related effects in effect-based action control.

Empirical investigations of ideomotor effect anticipations have mainly focused on action effects in the environment. By contrast, action effects that apply to the agent's body have rarely been put to the test in corresponding experimental paradigms. We present a series of experiments using the response-effect compatibility paradigm, in which we studied the impacts of to-be-produced tactile action effects on action selection, initiation, and execution. The results showed a robust and reliable impact if these tactile action effects were rendered task-relevant (Exp. 1), but not when they were task-irrelevant (Exps. 2a and 2b). We further showed that anticipations of tactile action effects follow the same time course as anticipations of environment-related effects (Exps. 3 and 4). These findings demonstrate that body-related action effects affect action control much as environment-related effects do, and therefore support the theoretical assumption of the functional equivalence of all types of action effects.