Deciphering Components of Impaired Working Memory in Multiple Sclerosis

Objective: To identify working memory (WM) impairment by examining components of auditory working memory with the same sample of individuals with multiple sclerosis (MS). Background: Although individuals with MS have consistently demonstrated WM impairments, the specific components involved (i.e., central executive versus storage/maintenance) remain unclear. Method: Individuals with MS with and without cognitive impairment and healthy controls were administered a task primarily assessing storage and rehearsal/maintenance (auditory n-back) and a task with a significant central executive component (Paced Auditory Serial Addition Task). Results: Results indicate when the phonological loop is minimally challenged, maintenance of information is generally efficient. However, the addition of a central executive component to processing appears to be the key factor in differentiating individuals with MS with cognitive impairment from those without cognitive impairment and healthy controls. Conclusions: Results indicated that the primary WM impairment in MS is within the central executive rather than the phonological loop.