Cognitive fog

Changes in thinking and memory

About 50 per cent of people with multiple sclerosis will develop some degree of cognitive fog. This generally means slowed ability to think, reason, concentrate, or remember.

However, only 5-10% of people develop problems that are severe enough to interfere in a significant way with everyday activities. While cognitive dysfunction is more common among people who have had the disease for a long time, it can be seen early in the disease course — even as the first symptom.

Multiple sclerosis may affect cognitive function for several reasons. First and foremost, it damages both myelin and the nerve cells within the brain, compromising a variety of functions handled by the brain. MRI studies have indicated that the extent of demyelination in the brain is related to severity of cognitive dysfunction.

However, multiple sclerosis can also affect cognition indirectly. The disease is often associated with depression, anxiety, stress and fatigue, all of which may compromise cognitive functioning. Fatigue can be particularly challenging to a person’s ability to sustain some mental tasks.

Find out more about symptoms, complications, assessment and treatment

Learn more: publications

Learn more: previous webinars

Thinking and Memory in MS - Lifestyle Factors and Cognition

Dr Heather Francis is a Clinical Neuropsychologist and Postdoctoral Researcher at Liverpool Hospital Neurology Department and the Psychology Department of Macquarie University
This webinar aims to discuss two of the major modifiable risk factors in MS: diet and exercise. The information provided will focus particularly on the mechanisms through which diet and exercise can alter the
pro-inflammatory state of multiple sclerosis, and what is currently known regarding the effects on cognition.

(Recorded September 2016)
Webinar Handouts : Lifestyle factors and Cognition

Thinking and Memory in multiple sclerosis

Thinking and memory changes in multiple sclerosis may go unrecognised. They are also often difficult for the person with multiple sclerosis and those around them to understand.

Ben Harris is a senior clinical neuropsychologist whose current public appointments are in community aged psychiatry for Monash Health, and in the Cognitive Dementia and Memory Service for St Vincent's Health.

This first session covers:

  • Brain changes in multiple sclerosis
  • Cognition and the brain; likely strengths and weaknesses with multiple sclerosis
  • Functional implications of cognitive changes in multiple sclerosis

Part 1

(Recorded July 2016)
Webinar handouts : Thinking and memory part 1

Part 2

The second session will cover strategies to assist in managing these changes.

(Recorded March 2017)
Webinar handouts : Thinking and memory part 2

Thinking and memory - improving your memory

Recorded November 2016
Webinar handouts : Thinking and memory - improving your memory

Thinking and memory - maintaining your attention

Recorded November 2016
Webinar handouts : Thinking and memory - maintaining your attention
Read more about Ben Harris


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