The difference in activation of the prefrontal cortex between a single motor task, a single cognitive task and a cognitive-motor dual task in persons with MS and healthy controls. A pilot study

Abstract

Objective: This study aims to investigate the PFC activation and behavioural performance during a single motor task (SMT), a single cognitive task (SCT) and a DT, in persons with MS (pwMS) and healthy controls (HC). Measurements: PFC activation was measured with the functional near-infrared spectroscopy (fNIRS) system during SMT (walking), SCT (subtracting 7s) and DT (walking while subtracting 7s). Outcome measures for motor and cognitive performances during single and dual tasking were distance walked and correct answers and accuracy, respectively. Additionally, motor and cognitive dual task cost (DTC) was calculated during combined execution. Results: No group*task interactions were found. As main effect, pwMS walked significantly slower than HCs. Further, both groups showed lower motor and cognitive (subtracting 7s) performance during DT compared to single tasks, however no differences between groups were found for the DTCs. The left dorsolateral PFC shows higher activation in pwMS and higher SMT activation compared to SCT and DT. The right dorsolateral PFC shows higher DT activations compared to SCT. No effects were found for brain activation in the frontopolar PFC.