Effects of a single-task versus a dual-task paradigm on cognition and balance in healthy subjects.

Abstract
Context: Recent evidence has revealed deficiencies in the ability to divide attention after concussion.Objective: To examine the effects of a single vs a dual task on cognition and balance in healthy subjects and to examine reliability of 2 dual-task paradigms while examining the overall feasibility of the tasks.Design: Pretest–posttest experimental design.Setting: Sports medicine research laboratory.Patients: 30 healthy, recreationally active college students.Intervention: Subjects performed balance and cognitive tasks under the single- and dual-task conditions during 2 test sessions 14 d apart.Main Outcome Measures: The procedural reaction-time (PRT) test of the Automated Neuropsychological Assessment Metrics (eyes-closed tasks) and an adapted Procedural Auditory Task (PAT; eyes-open tasks) were used to assess cognition. The NeuroCom Sensory Organization Test (SOT) and the Balance Error Scoring System (BESS) were used to assess balance performance. Five 2-way, within-subject ANOVAs and a paired-samples t test were used to analyze the data. ICCs were used to assess reliability across 2 test sessions.Results: On the SOT, performance significantly improved between test sessions (F1,29 = 35.695, P < .001) and from the single to the dual task (F1,29 = 9.604, P = .004). On the PRT, performance significantly improved between test sessions (F1,29 = 57.252, P < .001) and from the single to the dual task (F1,29 = 7.673, P = .010). No differences were seen on the BESS and the PAT. Reliability across test sessions ranged from moderate to poor for outcome measure.Conclusions: The BESS appears to be a more reliable and functional tool in dual-task conditions as a result of its increased reliability and clinical applicability. In addition, the BESS is more readily available to clinicians than the SOT.