Cognitive Function in MS

Anthony Feinstein MPhil, PhD, FRCP

Professor, Department of Psychiatry

University of Toronto and Sunnybrook Health 

Sciences Centre 

 Multiple Sclerosis (MS) is the most common non-traumatic cause of neurological disability in young and middle-age adults. MS affects balance, vision, strength and coordination. These symptoms are often quite visible. However, some symptoms are invisible and may be even more disabling. Examples include pain, fatigue, depression and cognitive dysfunction. 

Prevalence and nature of symptomsCognition refers to how we think, identify knowledge and understand it. Cognitive difficulties affect between 40 and 70% of people with MS. Individuals with progressive MS are more likely to have cognitive problems than individuals with relapsing-remitting MS. Problems with thinking and memory can start early in the disease. These problems may worsen over time interfering with day-to-day functioning.

The typical cognitive abnormalities that occur in people with MS are a decrease in processing speed, impairments in working memory and learning and deficits in executive functions. Processing speed refers to the time it takes to do a mental task. Executive function refers to a person’s ability to plan and execute solutions to problems while remaining flexible in terms of the decision-making processes. Of all these cognitive challenges, it is the slowing of information processing speed that is considered the cardinal cognitive difficulty linked to MS.