Visual and verbal working memory loads interfere with scene viewing

Working memory is thought to be divided into distinct visual and verbal subsystems. Studies of visual working memory frequently use verbal working memory tasks as control conditions and/or use articulatory suppression to ensure visual load remains in visual memory. Using these verbal tasks relies on the assumption that the verbal working memory load will not interfere with the same processes as visual working memory. In the present study, participants maintained a visual or verbal working memory load while simultaneously viewing scenes. Because eye movements and visual working memory are closely linked, we anticipated the visual load would interfere with scene viewing (and vice versa), while the verbal load would not. Surprisingly, both visual and verbal memory loads interfered with scene viewing behavior, while scene viewing did not significantly interfere with performance on either memory task. These results suggest that a verbal working memory load can interfere with a visual task and contribute to the growing literature suggesting the visual and verbal subsystems of working memory are less distinct than previously thought. Our data also stands at odds with previous work suggesting that visual working memory is obligatorily recruited by saccadic eye movements.