Detecting cognitive fatigue in multiple sclerosis: method matters.

Area of Science:

• Neuroscience
• Clinical Psychology

Background:

• Fatigue is a common and disabling symptom in multiple sclerosis (MS).
• Cognitive fatigue (CF) is characterized by reduced performance during sustained cognitive tasks.
• Understanding CF detection methods is crucial for managing MS symptoms.

Purpose of the Study:

• To evaluate the effectiveness of the Paced Auditory Serial Addition Task (PASAT) and the Computerized Test of Information Processing (CTIP) in detecting cognitive fatigue (CF) in MS.
• To examine the impact of different methodologies on CF detection.
• To investigate the relationship between objective and subjective measures of fatigue.

Main Methods:

• 70 individuals with MS and 72 healthy controls (HC) completed the PASAT (3-second and 2-second intervals) and CTIP.
• Subjective fatigue was assessed using the Fatigue Impact Scale (FIS).
• Data were analyzed to compare performance between groups and correlate objective and subjective fatigue measures.

Main Results:

• Both MS and HC groups performed worse on cognitively demanding tasks.
• PASAT performance varied between groups at the 3-second interval, with MS patients showing increased susceptibility to CF over time.
• The relationship between subjective and objective fatigue measures differed based on methodology, with PASAT showing good correlation with the FIS Cognitive Dimension.

Conclusions:

• The PASAT is a sensitive tool for measuring cognitive fatigue (CF) in multiple sclerosis (MS).
• The percent dyad scoring method of the PASAT is particularly sensitive to CF.
• The ability to link objective and subjective fatigue measures is dependent on the chosen methodology.