Contributions of Cognitive Function to Straight- and Curved-Path Walking in Older Adults

Abstract

Objective To determine whether the cognitive function contribution to straight- and curved-path walking differs for older adults. Design Cross-sectional observational study. Setting Ambulatory clinical research training center. Participants One hundred six people aged 65 years to 92 years, able to walk household distances independently with or without an assistive device, and who scored ≥ 24 on the Mini-Mental State Examination. Intervention Not applicable. Main Outcome Measurements Cognitive function was assessed using the Digit Symbol Substitution Test (DSST) as a measure of psychomotor speed, and Trail Making Tests A and B (Trails A, Trails B), and the Trail Making Test difference score (Trails B-A) as executive function measures of complex visual scanning and set-shifting. Gait speed recorded over an instrumented walkway was used as the measure of straight-path walking. Curved-path walking was assessed using the Figure-of-8 Walk Test (F8W) and recorded as the total time and number of steps for completion. Results Both DSST and Trails A independently contributed to usual gait speed (P < 0.001). Trails A performance contributed to F8W time (P < 0.001). Neither Trails B nor Trails B-A contributed to usual gait speed or time to complete the F8W. For the number of steps taken to complete the F8W, Trails A, Trails B, and Trails B-A (all P < 0.001) were independent contributors while DSST performance was not. Conclusion Curved-path walking, as measured by F8W test, involves different cognitive processes compared to straight-path walking. Cognitive flexibility and set-shifting processes uniquely contributed to how individuals navigated curved-paths. The measure of curved-path walking provides different and meaningful information about daily life walking ability than usual gait speed alone.

A Comparison of Straight- and Curved-Path Walking Tests Among Mobility-Limited Older Adults

“…We observed that the Trails B test performance was associated with performance on both walking performance tests. Consistent with our findings, prior studies have linked certain aspects of cognition with performance on F8WT and HGS tests (27). The Trails-making test part B measures cognitive skills such as attention, working memory, and cognitive flexibility (all executive functions), as well as psychomotor speed and visuoperceptual abilities (15,28).…”

Changes in oxygenated hemoglobin link freezing of gait to frontal activation in patients with Parkinson disease: an fNIRS study of transient motor-cognitive failures

“…During anticipated turns, the patient walks toward the point where he needs to turn while visual information is integrated with other sensory-motor inputs necessary to perform the task [4,14]. This information processing is associated with executive function thought to take place in Brodmann 10.…”

“…We used fNIRS during actual walking to examine frontal lobe activation before and during FOG. We focused on turns since they are one of the most common provokers of FOG and since turns are associated with increased executive function demands [14] and place greater demands on the coupling between posture, gait and perceptual processing and planning [17,27]. Accordingly, we hypothesized that frontal activation patterns would be altered during turns with FOG, compared to turns without FOG.…”

Determinants of Gait Speed in COPD

“…25 Cognitive function was evaluated with the Digit Symbol Substitution Test (DSST), where the subject copies as many novel symbols corresponding to numbers as possible in 90 s, providing a reliable measure of psychomotor speed, attention, and visual scanning. [26][27][28] A general survey was also used, addressing smoking status, frequency of COPD exacerbations, and health-care use (number of ED or hospital visits in the prior year).…”