Spieser, L. 1, 2, 3 , Casini, L. 1, 3, 2 , Hasbroucq, T. 1, 2, 3 & Burle, B. 1, 2, 3
1 Laboratoire de Neurobiologie de la Cognition, UMR 6155, Marseille
2 CNRS
3 Université de Provence, Marseille
In conflicting situations, control of responses activation is crucial in order to provide actions appropriated to the context. By studying those processes using a Simon task, previous studies have led to the development of the activation-suppression model. According to this model, the early activation of the spatially-corresponding response is followed by the inhibition of this response. We test this model using a Simon task, combined with a Change task: on some trials of a classical Simon task, during the subject's reaction time, a change of stimulus color indicates the need to change the response (thus, congruent trials become incongruent, and incongruent trials become congruent). Using different delays between the first stimulus presentation and the color change allow us to investigate the dynamics of the responses activation and inhibition. A non-trivial prediction of the activation-suppression model is that when the color change occurs at a long delay after the stimulus, switching from a congruent to an incongruent response should be easier than from an incongruent to a congruent response, because of the (relative) suppression of the spatially-corresponding response at this moment. First results seem to confirm this prediction.