Objective To determine if concussion history and post-concussion sleep quantity changes influence neurocognitive performance following concussion in collegiate athletes. It was hypothesised that athletes with a concussion history or shorter sleep duration following concussion would have poorer neurocognitive performance compared to athletes without a concussion history or greater sleep duration

Design Prospective cohort.

Setting Clinical Research Laboratory.

Participants Twenty-eight collegiate athletes (21 males and 7 females: age=20.2 ± 1.7 years, height=182.2 ± 11.9 cm, mass=90.3 ± 24.2 kg) without history of: headaches or migraines, substances/alcohol abuse, and/or psychiatric conditions.

Intervention Participants completed a preseason baseline and post-injury (PI) evaluation (1 day PI) using Immediate Post-Concussion Assessment and Cognitive Testing

Outcome measures Sleep change was calculated by subtracting post-injury sleep duration from baseline sleep duration. Athletes were categorised into either shorter sleep (<-1 hour change) or longer/same sleep (≥−1 hour change) groups. Independent samples t-tests were conducted to compare neurocognitive composite scores (verbal memory, visual memory, visual motor speed, reaction time, impulse control) between concussion history and sleep quantity change groups (α=0.05)

Main results Athletes with a concussion history had a faster reaction time (RT) (history:0.57±0.06 sec, no history:0.63±0.10 sec; p=0.048), but were more impulsive (history:8.55±5.87 errors, no history:4.18±3.89 errors; p=0.045) compared to those without a history of concussions. Neurocognitive performance did not differ between sleep quantity change groups.

Conclusions Athletes with a concussion history may be quicker to respond to neurocognitive tasks, but commit greater number of errors. Post-concussion sleep quantity changes do not influence neurocognitive performance one day post-injury. Future research should consider effects of concussion history on RT and impulse assessments.

Competing interests None.