The theory behind this study is that a dopamine deficiency may underlie the physical fatigue and cognitive difficulties experienced by polio survivors. This should be evident through increased levels of prolactin in plasma. It also should be associated with impaired cortical activation, evidenced by slowing of the electroencephalogram (EEG). The study involving 33 post-polio patients found such correlations. Dr. Bruno and his colleagues include chronic fatigue syndrome in discussing their results and suggest that “the findings provide a rationale for further study of the role played by the brain stem’s reticular activating system and dopaminergic neurons … in the genesis of fatigue and other fatigue-related cognitive symptoms.”
Bruno, R. L., Creange, S., Zimmerman, J.R. and Frick, N.M. (1998). Elevated plasma prolactin and EEG slow wave power in post-polio fatigue: Implications for a dopamine deficiency underlying post-viral fatigue syndromes. Journal of Chronic Fatigue Syndrome, 4:2, 61–75.