Cognitive-Motor Interference during Walking in Older Adults with Probable Mild Cognitive Impairment

Abstract

Although several studies have shown that dual-tasking (DT) mobility is impaired in Alzheimer's disease, studies on the effects of DT conditions in probable Mild Cognitive Impairment (pMCI) have not yielded unequivocal results. The objectives of the study were to (1) examine the effect of a concurrent task on a complex walking task in adults with cognitive impairment; and (2) determine whether the effect varied with different difficulty levels of the concurrent task. Furthermore, the study was designed to evaluate the Trail-Walking Test (TWT) as a potential detection tool for MCI. We examined DT performance in 42 young adults (mean age 23.9 ± 1.98), and 43 older adults (mean age 68.2 ± 6.42). The MoCA was used to stratify the subjects into those with and without pMCI. DT was assessed using the TWT: participants completed 5 trials each of walking along a fixed pathway, stepping on targets with increasing sequential numbers (i.e., 1-2-…-15), and increasing sequential numbers and letters (i.e., 1-A-2-B-3-…-8). Motor and cognitive DT effects (DTE) were calculated for each task. ROC curves were used to distinguish younger and healthy older adults from older adults with pMCI. The TWT showed excellent test-retest reliability across all conditions and groups (ICC : 0.83–0.97). SEM% was also low (<11%) as was the MDC95% (<30%). Within the DT conditions, the pMCI group showed significantly longer durations for all tasks regardless of the cognitive load compared to the younger and the healthy older adults. The motor DTEs were greatest for the complex condition in older adults with pMCI more so than in comparison with younger and healthy older adults. ROC analyses confirmed that only the tasks with higher cognitive load could differentiate older adults with pMCI from controls (area under the curve >0.7, p < 0.05). The TWT is a reliable DT mobility measure in people with pMCI. However, the condition with high cognitive load is more sensitive than the condition with low cognitive load in identifying pMCI. The TWT-3 thus could serve as a screening tool for early detection of individuals with pMCI. Future studies need to determine the neural correlates for cognitive-motor interference in older adults with pMCI.

Complex Gait Is Related to Cognitive Functioning in Older People: A Cross-Sectional Study Providing an Innovative Test

“…The Porteus Maze Test (PMT) [27] and Montreal Cognitive Assessment (MoCA) [13] are the neuropsychological tests recommended to analyze EF and for MCI screening, respectively, in older people [28]. In the PMT, participants must solve a series of increasingly difficult mazes by drawing a continuous pencil line from a given start to finish point without entering a dead end.…”

“…In particular, walking performance is a strong biomarker of health [10]. Gait speed (GS), gait variability, and step length are the most commonly used measures to predict cognitive decline [11][12][13][14][15]. In this regard, the preferred walking speed in older people is an indicator of general health and survival, and safe walking requires intact cognition and executive control [13].…”

“…Gait speed (GS), gait variability, and step length are the most commonly used measures to predict cognitive decline [11][12][13][14][15]. In this regard, the preferred walking speed in older people is an indicator of general health and survival, and safe walking requires intact cognition and executive control [13]. Additionally, deficits in cognitive domains, particularly those related to the prefrontal cortex, contribute to diminished walking performance in complex conditions during older ages [14].…”

Profiles of Cognitive-Motor Interference During Walking in Children: Does the Motor or the Cognitive Task Matter?

“…This occurs when the two tasks interfere with one another, known as cognitive-motor interference (CMI), and is thought to be a proof of capacity limitation in cognitive abilities ( Watanabe and Funahashi, 2014 ). An increase in CMI during gait has been shown in younger and older adults with and without multiple clinical conditions such as concussion, Multiple Sclerosis, Parkinson, or dementia resulting in impaired functional gait performance and increased risk of falls ( Wajda and Sosnoff, 2015 ; Smith et al, 2016 ; Belghali et al, 2017 ; Klotzbier and Schott, 2017 ; Schott, 2017 ; Fino et al, 2018 ). However, data is limited for both healthy children and adolescents.…”

Reliability and construct validity of a novel motor–cognitive dual‐task test: A Stepping Trail Making Test

“…10 To our knowledge, only three studies have attempted to identify the usefulness of the Trail-Walking Test, which converted the fall and cognitive impairment associated standard neuropsychological test (TMT-A) by loading a cognitive task on a mobility task, for predicting falls in older adults and cognitive impairment. [11][12][13] As it is yet to be verified whether dual-task tests involving visuospatial secondary tasks predict falls more strongly than a single walking test, 9 the S-TMT may clarify the mechanism of motor and cognitive interactions in the development of dementia and onset of falls using different aspects from previous studies. However, test reliability and the types of cognition and motor functions associated with the S-TMT remain unclear.…”