Processing speed versus working memory: contributions to an information-processing task in multiple sclerosis.

Individuals with multiple sclerosis (MS) often experience cognitive impairments in information processing. However, the relative contributions of processing speed abilities and working memory abilities to information-processing tasks are not yet fully understood. The current study examined the extent to which processing speed and/or working memory abilities contributed to an information-processing task, the Keeping Track Task (KTT). Forty-nine individuals with MS were given tests to assess processing speed and working memory, as well as the KTT. Regression analyses indicated that in the MS group, processing speed abilities accounted for the majority of the explained variance in KTT performance. The findings suggest that processing speed plays a significant role on KTT performance in MS. Implications for cognitive rehabilitation treatments aimed at improving processing speed abilities in MS are discussed.