Visual evoked potentials and signal detection following a marathon race.

Five marathon runners participated in a visual sustained attention experiment 1 week prior to a competitive martathon race and from 1.5 to 8.5 h following the race. The task was designed to help assess changes in central nervous system function by examinining both behavioral deficits and electroencephalogram (EEG) visual evoked potentials as a function of the race. A significant increase in heart rate was observed during the behavioral task. No changes in any of the wave forms of the EEG visual evoked response were observed during the vigilance task as a function of the race. Sustained visual attention responses were unchanged for correct detections, but post-marathon performance gave significantly fewer false positive responses. The results provided evidence that central nervous system dysfunction was not observed following the completion of a competitive marathon race.