Abstract
Decision-making has often been studied by asking observers to choose between two movements (e.g., a saccade to a target on the left or right of fixation). Choosing a movement with the highest expected value is adaptive, in that it maximizes reward over time. Saccadic reaction time (SRT) is used as a conventional index of movement preparation in such tasks. In the current study, latencies to initiate a saccade to a red target dot presented to the left or right of fixation were measured. Reward manipulations consisted of varying the magnitude of the reward, as well as the probability of receiving the reward, following a correct eye movement to the left or right target. Results show that higher expected reward leads to lower saccadic reaction times (SRT) to the target, taken to imply better saccadic preparation, and supporting previous findings by Milstein & Dorris (2007).