Dual-task performance

• P- another strength is that studies of dual-task performance support the separate existence of the visuo-spatial sketchpad
• E- when Baddeley et al’s (1975) participants carried out a visual and verbal task at the same time (dual task), their performance on each was similar to when they carried out the tasks separately. but when both tasks were visual or both tasks were verbal, performance on both declined substantially
• E- this is because both visual tasks compete for the same subsystem (VSS) whereas there is no competition when performing a verbal and visual task together
• L- this shows there must be a separate subsystem (the VSS), that processes visual input (and one for verbal processing, the PL)