Changes in neuropsychological test performance over the workday in multiple sclerosis.

Area of Science:

• Neuroscience
• Clinical Psychology

Background:

• Fatigue is a primary symptom of multiple sclerosis (MS), impacting daily activities and quality of life.
• The relationship between MS, cognitive performance decline over time, and subjective fatigue reporting remains debated.
• Previous studies show mixed results regarding objective cognitive fatigue in MS patients during prolonged mental tasks.

Purpose of the Study:

• To investigate objective cognitive fatigue in multiple sclerosis (MS) patients compared to controls.
• To examine the relationship between subjective fatigue ratings and objective cognitive performance over a workday.
• To determine if MS patients exhibit greater cognitive decline than controls after a typical workday.

Main Methods:

• Participants with MS and controls underwent a timed walk, fatigue ratings, and four cognitive tests.
• Cognitive assessments were administered before and after a normal workday.
• Objective measures included cognitive test performance and timed walk speed; subjective measures included fatigue ratings.

Main Results:

• Multiple sclerosis (MS) patients walked slower and scored lower on two cognitive tests compared to controls.
• No significant difference in the decline of objective cognitive performance was observed between MS patients and controls over the workday.
• MS patients reported a greater increase in subjective fatigue levels throughout the day compared to controls.

Conclusions:

• Subjective fatigue ratings in multiple sclerosis (MS) patients are not reliable indicators of objective cognitive performance.
• Objective cognitive fatigue in MS may not be accurately modeled by laboratory studies using prolonged, taxing tasks.
• Current findings suggest that MS fatigue's impact on cognition may be more nuanced than previously thought, especially in real-world work contexts.