We investigated the association between executive dysfunction and PFC activity during DT walking in patients with stroke.
Eighteen patients with stroke participated in this cross-sectional study. Executive function was assessed using the Trail Making Test (TMT) Part B minus Part A (ΔTMT). Patients performed a 10 m-walking test, and the protocol consisted of two sessions of normal walking and number subtraction DT walking after 30 s of resting while standing in random order. Walking speed was defined as a comfortable walking speed, and total hemoglobin (TH) values were measured at 10 Hz using functional near-infrared spectroscopy, with the affected and unaffected PFC as regions of interest. In addition, a subtraction task was performed to measure the underlying calculation ability in a sitting position. Walking analysis was performed to calculate the walking speed, number of subtraction tasks, percentage of correct responses, and reaction time. DTI was calculated following formula; [(normal walking time-DT walking time)/normal waking time]*100. For brain activity, the difference between walking and standing at rest was calculated after noise processing. Statistical analyses were performed using the Wilcoxon test for differences in walking speed and PFC-TH values between the normal walking and DT walking. The relationship between ΔTMT and changes in PFC-TH values was then evaluated using Spearman's correlation analysis.
DT walking time was significantly increased compared to normal walking time (P 0.05), and the DTI was 16.6 ± 15.2%. For the calculation task, the number of subtraction tasks and percentage of correct responses decreased during DT walking compared to that during sitting; however, there was no significant difference in reaction time. The amount of TH value change between standing at rest and walking conditions was significantly higher in the affected PFC than in the unaffected PFC. Furthermore, compared to the effect of normal walking, DT walking caused a smaller change in the affected PFC TH value from that during standing at rest. The values of differences in TMT and affected PFC TH values obtained during standing at rest and DT walking showed a significant negative correlation (ρ = −0.525, P 0.05).
Executive dysfunction is associated with changes in intact PFC activity during DT walking in patients with stroke.
The DT walking test should focus on executive function and not just walking in patients with stroke.
Executive function
Dual task walking
