Prospective memory in multiple sclerosis.

There is considerable evidence that multiple sclerosis (MS) is associated with impaired retrospective memory. However, although preliminary evidence suggests that prospective memory is also affected by the disorder, the degree and nature of the impairment remains to be clarified. Twenty participants with MS were compared with 20 matched controls on Virtual Week, a measure of prospective memory that closely represents the types of prospective memory tasks that actually occur in everyday life, and provides an opportunity to investigate the different sorts of prospective memory failures that occur. The results indicated that irrespective of the specific prospective memory task demands, MS participants' performance was significantly impaired relative to controls. MS deficits could not be attributed to problems with retrospective memory because MS participants in the present study did not differ significantly from controls on measures of long- and short-term memory, and significant impairment was observed on a prospective memory task, which imposed only minimal demands on retrospective memory. These results therefore suggest that individuals with MS may experience general difficulties with prospective memory. The practical and theoretical implications of these findings are discussed.