Abstract
Objectives
Recent retrospective studies report differences in auditory neurophysiology between concussed athletes and uninjured controls using the frequency-following response (FFR). Adopting a prospective design in college football players, we compared FFRs before and after a concussion and evaluated test-retest reliability in non-concussed teammates.
Design
Testing took place in a locker room. We analysed the FFR to the fundamental frequency (F0) (FFR-F0) of a speech stimulus, previously identified as a potential concussion biomarker. Baseline FFRs were obtained during the football pre-season. In athletes diagnosed with concussions during the season, FFRs were measured days after injury and compared to pre-season baseline. In uninjured controls, comparisons were made between pre- and post-season.
Study Sample
Participants were Tulane University football athletes (n = 65).
Results
In concussed athletes, there was a significant group-level decrease in FFR-F0 from baseline (26% decrease on average). By contrast, the control group’s change from baseline was not statistically significant, and comparisons of pre- and post-season had good repeatability (intraclass correlation coefficient = 0.75).
Conclusions
Results converge with previous work to evince suppressed neural function to the FFR-F0 following concussion. This preliminary study paves the way for larger-scale clinical evaluation of the specificity and reliability of the FFR as a concussion diagnostic.
This prospective study reveals suppressed neural responses to sound in concussed athletes compared to baseline.
Neural responses to sound show good repeatability in uninjured athletes tested in a locker-room setting.
Results support the feasibility of recording frequency-following responses in non-laboratory conditions.
Highlights
Acknowledgments
The authors thank the athletes of the Tulane football program and the athletic staff including Andy Massey, David Gambel, Nathan Quebedeaux, and Ryan Larkin. The Eye and Ear Foundation of Pittsburgh provided the equipment used in this study. The authors also thank Ashley Parker for her feedback on an earlier version of the manuscript.
Disclosure statement
No potential conflict of interest was reported by the author(s).