Interference effects between saccadic and key-press reaction times of volleyball players and nonathletes

To investigate the interference effect in volleyball players and nonathletes (ns=10) when they executed both saccadic and key-press reaction time (RT) tasks concurrently, the two groups responded to the onset of peripheral visual stimuli as quickly as possible in single and dual conditions. In the single condition, subjects responded with either saccadic eye or key-press movement. In the dual condition, they responded concurrently with both saccadic eye and key-press movements. In both groups, the key-press RT was longer in the dual condition than in the single condition. However, the amount of key-press RT delay was remarkably smaller for the volleyball players than for nonathletes. This suggests the motor command to initiate manual movement of volleyball players might be less interfered with by a concurrent oculomotor command to initiate saccadic eye movement when compared to that of nonathletes.