Balance Performance With a Cognitive Task: A Continuation of the Dual-Task Testing Paradigm. 
Jacob E. Resch, PhD, ATC; Bryson May, MS; Phillip D. Tomporowski, PhD; Michael S. Ferrara, PhD, ATC, FNATA.  Journal of Athletic Training 2011;46(2):170–175.
Sport related concussion is a brain injury that has the potential for devastating acute and long-term outcomes in some individuals.  It represents over 3 million injuries annually in the US, and this number is likely to rise as concussion education is enhanced and assessments become more precise.  We have learned that concussions can present differently from athlete to athlete and because of this it is important to use assessments that cover multiple areas.  Specifically, to identify concussions clinicians should include symptom, neuropsychological, and postural assessments during their evaluation. In the current study the authors examine a concussion assessment that requires participants to perform balance and cognitive tasks simultaneously. The thought being that with the increased demands created by the dual task it would be easier to detect more subtle neural disturbances caused by concussions.  This would potentially aid in concussion detection and return to play timing. Twenty healthy college-aged men and women participated in two test sessions.  During the test sessions participants performed balance (Sensory Organization Test with the Neurocom Smart Balance Master) and cognitive tasks individually or simultaneously.  The cognitive task consisted of an auditory switch test where the person had to identify odd or even numbers and consonant or vowels correctly and as fast as possible (accuracy and reaction time were assessed).  During the dual task balance was maintained but cognitive function was diminished (increased errors and time) compared to the single task when categories (numbers and letters) were utilized together during the trials. 
This study illustrates very good laboratory work trying to identify enhanced concussion assessment instruments.  Increasing test demands to identify subtle alterations in various systems potentially affected by concussion is the reason behind many advances in assessment instruments (e.g., Romberg vs. BESS).  As the authors note it is important to know that this dual task technique is not ready for prime time as further research using a concussed population is needed.  This research is likely soon to follow as athletic training concussion researchers continue to push the envelope to enhance patient care.    
Written by: Ryan Tierney
Reviewed by: Jeffrey Driban