Electrophysiological evidence for the cumulative effects of concussion

Purpose: A study was initiated with the intent of demonstrating the cumulative effects of concussion in junior hockey players using visual event-related potentials and post-concussion syndrome (PCS) self-reports. Methods: Players were assessed at the beginning of the season (pre-injury) and at various times post-injury. Results: The results suggest that players with three or more concussions differed significantly on the several cognitive PCS symptoms as well as for the latency of the P3 response compared to those with no concussion history. Discussion: Event-related potentials are useful indices of the cumulative damage that can occur following multiple concussions. These measures correlate significantly with cognitive self-reports of PCS symptoms. Conclusions: This pattern of results is consistent with the position that each concussion potentially causes brain damage. Cumulative damage can be detected using electrophysiological measures of brain function.