Task coordination between and within sensory modalities: effects on distraction.

Load theory predictions for the effects of task coordination between and within sensory modalities (vision and hearing or vision only) on the level of distraction were tested. Response competition effects in a visual flanker task when it was coordinated with an auditory discrimination task (between-modality conditions) or a visual discrimination task (within-modality conditions) were compared with single-task conditions. In the between-modality conditions, response competition effects were greater in the two- (vs. single-) task conditions irrespective of the level of discrimination task difficulty. In the within-modality conditions, response competition effects were greater in the two-task (vs. single-task) conditions only when these involved a more difficult visual discrimination task. The results provided support for the load theory prediction that executive control load leads to greater distractor interference while highlighting the effects of task modality.