Objective Measurement of Cognitive Fatigue in Multiple Sclerosis

Bryant, Deborah
Chiaravalloti, Nancy D.
DeLuca, John

¹Neuropsychology and Neuroscience Laboratory, Kessler Medical Rehabilitation Research and Education Corporation, West Orange, New Jersey
²Department of Physical Medicine Rehabilitation, University of Medicine and Dentistry of New Jersey.

³Correspondence concerning this article should be addressed to John DeLuca, PhD, Kessler Medical Rehabilitation Research and Education Corporation, 1199 Pleasant Valley Way, West Orange, NJ 07052. E-mail: [email protected].

This project was supported in part by National Institutes of Health Grants T32 HD07522 and R01 HD38249 and by National Multiple Sclerosis Foundation Grant RG 2596B2.

Received Date: May 28, 2002; Revised Date: September 12, 2002; Accepted Date: November 19, 2002

Rehabilitation Psychology 49(2):p 114-122, May 2004.

Objective

Objective examination of cognitive fatigue in persons with multiple sclerosis (MS).

Participants

Fifty-six individuals with MS and 39 age- and education-matched healthy control subjects.

Main Outcome Measures

Cognitive fatigue, operationalized as the failure to sustain effort over the course of a continuous working memory task; performance on the Paced Auditory Serial Addition Test was examined, with number of correct responses generated and responses produced under conditions of sustained central executive load as the dependent variables.

Results

Cognitively impaired MS subjects produced significantly fewer correct responses than either nonimpaired MS subjects or healthy control subjects, who performed at a comparable level. Both MS groups, however, showed susceptibility to cognitive fatigue significantly earlier in time than the healthy group.

Conclusions

Fatigue can influence performance even in the absence of cognitive impairment.