Concussion history is negatively associated with visual-motor force complexity: evidence for persistent effects on visual-motor integration

ABSTRACT

Objectives: Long-term monitoring of concussion recovery requires time- and cost-effective methods. Physiologic complexity may be useful in evaluating visual-motor integration following concussion. The purpose of this study was to quantify the extent to which prior number of concussions influenced visual-motor tracking force complexity.

Methods: Thirty-five individuals with a self-reported concussion history (age: 20.92 ± 1.98) and 15 without (age: 20.92 ± 2.21) performed an isometric visual-motor tracking task, using index finger force to trace a straight line across a computer screen. Finger force root mean square error (RMSE), multi-scale complexity, and average power from 0 to 12 Hertz (Hz) were calculated. Individual multiple regressions were fit to these outcomes.

Results: Force complexity decreased linearly with an increasing number of concussions (R² = 0.101). Males had more complex force overall (R² = 0.219) and greater 4–8 Hz average power (R² = 0.193). The 8–12 Hz average power decreased significantly for individuals with prior loss of consciousness (LOC) and increasing numbers of concussions (R² = 0.143).

Conclusion: Individuals exhibited linear decreases in visual-motor tracking force complexity with increasing numbers of concussions, influenced by both gender and a history of LOC. These findings indicate cumulative changes in the ways in which previously concussed individuals process and integrate visual information to guide behaviour.

KEYWORDS:

• Concussion
• mild traumatic brain injury
• multi-scale complexity
• visual-motor tracking

Supplementary data

Supplemental data for this article can be accessed on the publisher’s website.

Acknowledgments

The authors would like to acknowledge the input on the project and manuscript by Dr Eadric Bressel, Dr Tom Higbee, and Dr Idalis Villanueva at Utah State University.

Declaration of interest

The authors report no declarations of interest.

Additional information

Funding

No funding sources were utilized in the preparation of this article.