<p>The association between cognition and dual-tasking among older adults: the effect of motor function type and cognition task difficulty</p>

Abstract

Background Dual-task actions challenge cognitive processing. The usefulness of objective methods based on dual-task actions to identify the cognitive status of older adults has been previously demonstrated. However, the properties of select motor and cognitive tasks are still debatable. We investigated the effect of cognitive task difficulty and motor task type (walking versus an upper-extremity function [UEF]) in identifying cognitive impairment in older adults. Methods Older adults (≥65 years) were recruited, and cognitive ability was measured using the Montreal Cognitive Assessment (MoCA). Participants performed repetitive elbow flexion under three conditions: 1) at maximum pace alone (Single-task); and 2) while counting backward by ones (Dual-task 1); and 3) threes (Dual-task 2). Similar single- and dual-task gait were performed at normal speed. Three-dimensional kinematics were measured for both motor functions using wearable sensors. Results One-hundred older adults participated in this study. Based on MoCA score <20, 21 (21%) of the participants were considered cognitively impaired (mean age =86±10 and 85±5 for cognitively impaired and intact participants, respectively). Within ANOVA models adjusted with demographic information, UEF dual-task parameters, including speed and range-of-motion variability were significantly higher by 52% on average, among cognitively impaired participant ( p <0.01). Logistic models with these UEF parameters plus age predicted cognitive status with sensitivity, specificity, and area under curve (AUC) of 71%, 81% and 0.77 for Dual-task 1. The corresponding values for UEF Dual-task 2 were 91%, 73% and 0.81, respectively. ANOVA results were non-significant for gait parameters within both dual-task conditions ( p >0.26). Conclusion This study demonstrated that counting backward by threes within a UEF dual-task experiment was a pertinent and challenging enough task to detect cognitive impairment in older adults. Additionally, UEF was superior to gait as the motor task component of the dual-task. The UEF dual-task could be applied as a quick memory screen in a clinical setting.

Effects of Combined Resistance and Power Training on Cognitive Function in Older Women: A Randomized Controlled Trial

“…In addition, reduced short-term memory is commonly found in people with AD [8]. Finally, reduced dual-task performance is observed according to dementia severity [10,12], and older adults with impaired ability to perform both motor and cognitive tasks simultaneously are at higher risk of falls and death [11].…”

“…On the other hand, dual-task, which involves the simultaneous performance of motor and cognitive tasks, challenges many cognitive domains, including attention, inhibitory control, and executive function [9,10]. In recent years, dual-task performance has been associated not only with physical outcomes (e.g., falls, disability) [11], but also with biological markers of dementia [9] and cognitive status [10,12], suggesting that reduced dual-task performance may serve as a marker of cognitive decline.…”

Screening older adults for amnestic mild cognitive impairment and early-stage Alzheimer’s disease using upper-extremity dual-tasking

“…Of note, all the above outcomes can be calculated using an in-home MATLAB app, within less than 1 minute. These parameters were selected to present alterations in motor function execution speed and accuracy within dual-tasking, based on our previous investigations and gait dual-task studies among dementia patients 12,17,18,40,41 . Using these parameters, changes in motor function due to the cognitive task were determined, which included: (1) agility (speed, rise time, and flexion number, which are analogous to gait speed, stride time, and cadence); (2) flexibility (ROM, which is analogous to step length); and (3) variability (speed, ROM, and flexion variability, which are analogous to gait speed, step length, and gait cycle time variability).…”

“…In previous work, we have determined strong correlations between UEF and gait speed 14 and six-minute walk distance 16 . Further, we have compared the UEF dual-task performance (simultaneous performance of UEF and a cognitive task of counting backward) with gait dual-task performance, as well as the Montreal Cognitive Assessment (MoCA) test 17,18 . Within this work, a significant association has been observed between UEF speed parameters and gait speed within the dual-task trials.…”

Does the Presence of Cognitive Impairment Exacerbate the Risk of Falls in People with Peripheral Neuropathy? An Application of Body-Worn Inertial Sensors to Measure Gait Variability

“…In the current study, we used the cutoff score of 22 and below to identify those with cognitive impairment [39]. MoCA was used to identify dual-task related motor dysfunction previously [40,41]. Additionally, we assessed for depression in each participant using the Center for Epidemiological Studies Depression Scale (CES-D) [42].…”