After a concussion, athletes may be at increased risk of musculoskeletal injuries. Altered perception of action boundaries (ABP), or the limits of one's action capabilities, is one possible mechanism for this increase in injury risk after concussion.
To evaluate differences in symptoms, neurocognitive, vestibular/oculomotor, and action boundary function between subjects with no concussion history (NoHx) and concussion history (ConcHX).
Laboratory at the University of Pittsburgh.
ConcHx (n = 22; age: 21.8 ± 3.0 years, height: 174.0 ± 8.3 cm, and mass: 77.8 ± 14.8 kg) and NoHx athletes (n = 24; age: 21.6 ± 2.0 years, height: 176.0 ± 10.0 cm, and mass: 72.0 ± 15.3 kg).
Immediate Postconcussion Assessment and Cognitive Testing (ImPACT) and Post-Concussion Symptom Scale (PCSS), Vestibular–Ocular Motor Screening (VOMS) tool, and the Perception–Action Coupling Task (PACT). The PACT measures the accuracy of ABP.
Main Outcome Measures:
Neurocognitive domain scores, PCSS, VOMS subdomain symptom gain, ABP accuracy, and actualization.
ConcHx reported 2.7 ± 1.5 previous concussions occurring on average 263.8 ± 228.9 days prior. ConcHx was higher on several VOMS items including vertical/horizontal saccades (P = 0.001; P = 0.05), vertical/horizontal vestibular–ocular reflex (P < 0.001; P = 0.04), and visual motion sensitivity (P < 0.001). Average PACT movement time (P = 0.01) and reaction time (P = 0.01) were longer in ConcHx.
These findings provide preliminary support for impaired vestibular/oculomotor function and ABP in ConcHx compared with NoHx. The current results may enhance our understanding of the mechanisms for increased musculoskeletal injury risk after concussion.