Action-effect Anticipation in Patients With Parkinson's Disease : A Study of the Sensory Attenuation Marker.

The ideomotor theory of action control is considered to be central to the understanding of human voluntary action. According to the ideomotor theory, an action is represented in terms of its desired sensory effects and actions are selected by internally activating these effect representations. Recent imagery and behavioral studies showed that this anticipated representation of action-effects triggered a "sensory attenuation", meaning a decrease of perceptive performances or a decrease of sensory event-related potentials (ERP) for an expected event. Thus, the sensory attenuation constitutes a relevant behavioral tool to investigate sensory anticipation impairment in patients with Parkinson's disease. In a behavioral paradigm, patients and matched control participants have to perform a perceptive task on predicted visual action-effects mixed with mispredicted visual action effects. Performances should be better in mispredicted visual action effects for control participants only.