Category: Neurodegenerative Disease (e.g. MS, Parkinson's disease); Neuroplasticity (includes neuroscience)
Objective : To examine the effect of multiple sclerosis (MS) on the cognitive control of gait and hemodynamic correlates of walking under single- and dual-task conditions in ecologically valid contexts.
Design : A quasi-experimental, single-group, time-series design
Setting : University research laboratory
Participants (or Animals, Specimens, Cadavers) : Fourteen volunteer subjects completed a 1-minute continuous walk under each of the following conditions: 1) counting backwards, 2) auditory Stroop, 3) walking as single task, 4) discourse task A, 5) discourse task B, 6) walking and discourse task A, 7) walking and discourse task B, 8) walking and counting backwards, and 9) walking and auditory Stroop.
Interventions : Not applicable
Main Outcome Measure(s) :
As a proxy for neuronal activation, blood flow to the pre-frontal cortex (PFC) in the brain was measured using functional near-infrared spectroscopy (fNIRS). Instrumented measures of gait were collected via wireless inertial sensors. Dual-task cost was calculated for cadence, double limb support, gait speed, and stride length. Dual-task cost was also derived for each cognitive task. A repeated measures analysis of variance and, if appropriate, post-hoc test was conducted for each variable. Significance was set at p
Results : Significant differences in dual-task cost were found for all gait parameters. The cognitive processing associated with categorization and natural discourse while walking resulted in the greatest dual-task costs. The dual-task cost for the cognitive tasks evidenced specific patterns of prioritization. PFC activation levels during dual-tasking compared to single-tasking further revealed cognitive-motor interference.
Conclusions : The results provide insight into the functional brain mechanisms of individuals with MS while they perform demanding and ecologically valid dual-tasks, such as walking and talking. Further investigation of the interconnection of gait, cognitive function, and PFC activation is warranted, as this understanding may help to inform targeted fall prevention programs.
Brittany Belanger– Student Research Assistant, University Of Vermont, Burlington, Vermont
Gabriel Purin– Student Research Assistant, University Of Vermont, Burlington, Vermont
Michael Cannizzaro– Associate Professor, University Of Vermont, Burlington, Vermont
Susan Kasser– Professor of Exercise Science, University of Vermont, Burlington, Vermont