The Effects of Different Attentional Focus During Walking on Prefrontal Cortical Activation in Young Healthy Adults

The aim of this study was to examine the effects of four attentional walking conditions on dorsolateral prefrontal cortex (DLPFC) activation, an approach that has not previously been investigated. We hypothesized that DLPFC activation and perceived workload would be higher, and gait performance more disrupted, during walking with internal focus or divided attention compared to walking with external focus or without focus instructions. Participants performed four walking conditions with different attentional orientations. The conditions were presented in a randomized order and were conducted with block design. A deleterious effect of internal focus and divided attention was observed on gait performance, indicating that internal focus induced more conscious control interfering with automatic control processes of gait and that, for divided attention, participants were inclined to focus on the cognitive task to the detriment of gait. We observed significant DLPFC activation for each of the tasks but no significant difference when we compared them with each other. Internal focus and divided attention led to significantly higher mental demand, suggesting that they required greater involvement of cognitive resources, but no significantly higher DLPFC activation was observed, suggesting that young adults sacrificed enough gait performance to avoid excessive resource demands. For each of the four tasks, a significantly higher level of activity was detected in the left DLPFC which is one of the regions involved in attentional refreshment.