A Mutual Relationship Between The Time Taken To Decide And To Move

Details

Supervisors

Duque, Julie ; Carsten, Thomas

Faculty

Faculté des sciences de la motricité

Degree label

Master [60] en kinésithérapie et réadaptation

Abstract

Decision-making followed by an action to report a choice is a complex process depending on different factors. Previous studies suggested that the decision process and motor preparation seem to coexist at the same time in the brain and seem to be linked. This work focuses on the study of this relationship between decision time (DT) and movement time (MT). We hypothesized that when it does not influence the reward rate (quantity of reward per unit of time), people naturally match DT and MT. We expect that a decision with a shorter DT should lead to a shorter MT and that a decision with the necessity of a fast movement to execute it will lead to a shorter DT. To test our hypothesis, we set up an online behavioural task where participants had to make a choice between two options using evolving evidence and execute it by multiple keypresses. Oppositely to previous studies, the task paradigm did not change the reward rate depending on the participants’ strategy. This confirmed that DT and MT tend to increase or decrease in the same way. We conclude that the link between decision-making and movement-making makes them influence each other, and that DT is probably influenced by the duration of all the potential actions following the different options. It would mean that decision and action are probably not two processes strictly separated, but one process with a progressive shift from abstract cognitive process to concrete movement, starting from the beginning of the decision-making.