“…This negative wave is thought to reflect activation of the motor cortex that controls the goal-directed correct response (e.g., C3 for responses by the right hand). Concurrently, a positive-going wave develops at electrodes contralateral to the non-selected response hand (i.e., ipsilateral to the responding hand; e.g., C4 for responses by the right hand) that is thought to reflect the simultaneous inhibition of activity in the motor cortex that controls production of the incorrect response (for reviews see Burle, 2004; Carbonell et al, 2004; Meckler et al, 2010; Meynier, Burle, Possamai, Vidal, & Hasbroucq, 2009; van de Laar et al, 2012; Vidal et al, 2003). Given the deficits in inhibitory action control among PD patients, we reasoned that the response-locked surface Laplacian technique could provide new insights about the degree of suppression of conflicting motor responses at M1, especially in situations involving speed stress.…”