Executive Dysfunction Following a Sport-Related Concussion is Independent of Task-Based Symptom Burden.

A sport-related concussion (SRC) results in short- and long-term deficits in oculomotor control; however, it is unclear whether this change reflects executive dysfunction and/or a performance decrement due to an increase in task-based symptom burden. Here, individuals with a SRC - and age- and sex-matched controls - completed an antisaccade task (i.e., saccade mirror-symmetrical to a target) during the early (initial assessment: ≤12 days) and later (follow-up assessment: < 30 days) stages of recovery. Antisaccades were used because they require top-down executive control and exhibit performance decrements following a SRC. Reaction time (RT) and directional errors were included with pupillometry because pupil size in the antisaccade task has been shown to provide a neural proxy for executive control. In addition, the Sport-Concussion Assessment Tool (SCAT-5) symptom checklist was completed prior to and after each oculomotor assessment to identify a possible task-based increase in symptomology. The SRC group yielded longer initial assessment RTs, more directional errors and larger task-evoked pupil dilations (TEPD) than the control group. At the follow-up assessment, RTs for the SRC and control group did not reliably differ; however, the former demonstrated more directional errors and larger TEPDs. SCAT-5 symptom severity scores did not vary from the pre- to post-oculomotor evaluation for either initial or follow-up assessments. Accordingly, a SRC imparts a persistent executive dysfunction to oculomotor planning independent of a task-based increase in symptom burden. These findings evince that antisaccades serve as an effective tool to identify subtle executive deficits during the early and later stages of SRC recovery.