This study investigated inhibition of return in persons with and without Down syndrome (DS) when visual or verbal cues were used to specify a target in a crossmodal paradigm. Individuals with DS and without DS performed manual aiming movements to a target located in right or left hemispace. The target was specified by an endogenous visual or verbal stimulus. Both groups were significantly slower when responding to the same target as the previous trial when the target was cued in a different modality. Although participants with DS initiated and executed their movements more slowly, they demonstrated a similar pattern of inhibition as people without DS, suggesting that inhibitory processes are functioning normally in persons with DS.
Cheryl Glazebrook, Digby Elliott, and James Lyons are with the Department of Kinesiology at McMaster University, Hamilton, ON Canada L8S 4K1. Email: firstname.lastname@example.org. Luc Tremblay is with the Faculty of Physical Education and Health at the University of Toronto, ON Canada M5S 2W6.