Original researchOutcomes, utility, and feasibility of single task and dual task intervention programs: Preliminary implications for post-concussion rehabilitation
Introduction
Concussions are the most frequent form of traumatic brain injury occurring in sport.1 Previously, the focus of concussion research has been on prevention, evaluation and acute management.2 Although much more is to be understood in these areas, further research is necessary to determine how rehabilitation3 and return-to-play progressions may play a role in recovery following a concussion. Although the majority of concussion symptoms resolve within a 7–10 days window,4 some individuals may suffer from Post Concussion Syndrome (PCS) where physical, cognitive, and emotional symptoms do not resolve for several months to years following injury.5
The current standard of care for sports-related concussion centers on cognitive and physical rest followed by gradual return to activity once the athlete is asymptomatic.2 If concussion symptoms include both cognitive and balance impairment, then it seems rational that clinicians should address these issues during the rehabilitation process to facilitate recovery. Rehabilitation has been used for patients with moderate and severe traumatic brain injury, but has not been considered as a standard of care for mild traumatic brain injury such as sport-related concussion with prolonged recovery.3 Medical professionals need to address the functional capacity of systems affected by concussion to ensure safe return to play.6 Following concussion the functional capacities of balance and cognitive resources are often impaired making dual-task executions more difficult.7, 8 It is unknown if each domain should be addressed separately in a “single-task” model, or if these tasks should be integrated in a “dual-task” model that more accurately represents the conditions a patient is going to encounter when returning to physical activity. This “dual-task” rehabilitation methodology would require a person to execute a secondary cognitive task while being physically exerted to address cognitive, balance, and or visual deficits following concussion.
To the best of our knowledge, no study has attempted to assess single vs. divided attention training intervention programs in an effort to provide background for future paradigms in concussion management. Therefore, the purpose of this study was to examine dual-task neurocognitive and balance performance in healthy collegiate recreational athletes, prior to and following a dual-task training intervention compared to matched single-task controls. The intent of this research was to determine the utility and feasibility of a dual-task training program to potentially be applied following concussion.
Section snippets
Methods
The study was conducted following the ethical guidelines set forth by the Department of Health and Human Services Office for Human Research Protection (U.S.A.) and approved by the University of North Carolina at Chapel Hill's (UNC-CH) institutional review board prior to study initiation (Reference Study # 11-0499). Participants represented a volunteer sample from sport clubs at the UNC-CH. All participants signed approved consent forms prior to participation. Thirty physically active males and
Results
We observed an improvement in measures of balance for both groups across time. Specifically, all participants, regardless of group, achieved a higher SOT vestibular ratio score and committed fewer errors during the BESS following intervention. No other significant interaction effects or main effects were observed for the balance measures. Descriptive and statistical results for balance measures are located in Table 2.
The single task group showed significantly greater improvement following their
Discussion
The primary findings of this study indicate that regardless of training type, participants significantly improved following both the dual- and single-task intervention on measures of executive function, complex attention, cognitive flexibility, and some measures of balance performance. Single-task controls had greater neurocognitive improvements in the domain of complex attention from pre- to post-test than the dual-task participants. These findings refute our hypothesis that dual-task
Conclusions
Our findings suggest that combining a cognitive task with a balance task, as performed by the dual-task group, does not have any additional benefits to performing these tasks independently, as with the single-task group among healthy individuals. There are potential benefits to a single-task progression, which may be beneficial to an injured population such as additional attention or balance training and controlled progression back into some activity. Balance and neurocognitive improvements may
Practical implications
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Healthy participants who completed a balance and cognitive rehabilitation protocol improved in the respective domains over time.
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A paradigm combining both balance and cognitive exercises would be feasible for health care professionals to complete during a rehabilitation session.
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Timing and length of both single and dual-task interventions should be considered as this may influence outcomes.
Conflicts of interest and source of funding
Drs. Register-Mihalik, Mihalik, and Guskiewicz received funding from the NC TraCS institute that supported this project. The NC TraCS Institute is supported by grants UL1TR000083, KL2TR000084, TL1TR000085 from the National Center for Advancing Translational Sciences, National Institutes of Health. The content is solely the responsibility of the authors and does not necessarily represent the official views of the NIH. The remaining authors have no disclosures or conflicts of interest.
Acknowledgement
The authors would like to acknowledge Ms. Mikel Stiffler for assistance with data collection.
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