The role of the peripheral target in stimulating eye movements.

The present study investigated the role of top-down and bottom-up processes during a deceptive sports strategy called "no-look passes" and how microsaccades and small saccades modulate these processes. The first experiment examined the role of expertise in modulating the shift of covert attention with the bottom-up procedure. Results showed more saccades of greater amplitude and faster peak velocity in amateur than in expert groups. In the second experiment, the shift of covert attention between top-down and bottom-up conditions was investigated in a group of expert basketball players. Analysis showed that athletes make more microsaccades during the bottom-up condition; meanwhile, during the top-down condition, they were pushed to make more small saccades to decide where to send the ball. The findings suggested that the top-down process stimulates the eyes to move more concerning the bottom-up condition. It could be explained by the fact that during the top-down condition, athletes do not have an "eyehold" that stimulates their attention. During the top-down condition, athletes had to shift their attention to both sides before making the pass, resulting in their eyes being more "hesitant" concerning the situation in which they are peripherally stimulated.