Medicine and Health Sciences Commons^™

Central Fatigue In Chronic Fatigue Syndrome, Peter A. J. Hope

Theses : Honours

Fatigue associated with activity is a normal response, seeking to prevent damage or conserve energy. Some individuals show heightened fatigue responses with no distinct aetiology. In chronic fatigue syndrome (CFS), peripheral fatigue mechanisms display no apparent abnormalities, indicating some central mechanism. Transcranial magnetic stimulation (TMS) was used to compare force, perceived exertion, electromyogram response, motor evoked potentials (MEP) and silent periods (SP) following stimulation in normal and chronic fatigue groups. Participants (n=l2) were physically matched and performed a sustained sub-maximal (20% of MVC) isometric contraction of the elbow flexors. There were no significant differences (p < 0.05) in elbow flexor strength or time to reach fatigue. CFS participants showed a significant difference in perception of effort at outset. Differences were also noted in MEP amplitude and SP duration (p