187 AGE-RELATED DIFFERENCES IN DUAL TASK EFFECTS OF SPONTANEOUS SPEECH AND EXECUTIVE FUNCTION ON GAIT SPEED

Abstract The simultaneous performance of a secondary task while walking (i.e., dual tasking) increases motor-cognitive interference and fall risk in older adults. Combining transcranial direct current stimulation (tDCS) with the concurrent performance of a task that putatively involves the same brain networks targeted by the tDCS may reduce the negative impact of dual-tasking on walking. We examined whether tDCS applied while walking reduces the dual-task costs to gait and whether this combination is better than tDCS alone or walking alone (with sham stimulation). In 25 healthy older adults (aged 75.7±10.5yrs), a double-blind, within-subject, cross-over pilot study evaluated the acute after-effects of 20 minutes of tDCS targeting the primary motor cortex and the dorsal lateral pre frontal cortex during three separate sessions:1) tDCS while walking on a treadmill in a virtual-reality environment (tDCS+walking), 2) tDCS while seated (tDCS+seated), and 3) walking in the virtual-reality environment with sham tDCS (sham+walking). The complex walking condition taxed motor and cognitive abilities. During each session, single- and dual-task walking and cognitive function were assessed before and immediately after stimulation. Compared to pre-tDCS performance, tDCS+walking reduced the dual-task cost to gait speed (p=0.004) and other gait features (e.g., variability p=0.02), and improved (p<0.001) executive function (Stroop interference score). tDCS+seated and sham+walking did not affect the dual-task cost to gait speed (p>0.17). These initial findings demonstrate that tDCS delivered during challenging walking ameliorates dual-task gait and executive function in older adults, suggesting that the concurrent performance of related tasks enhances the efficacy of the neural stimulation and mobility.

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Mild Cognitive Impairment Affects Obstacle Negotiation in Older Adults: Results from “Gait and Brain Study”

Gerontology ◽

10.1159/000492931 ◽

2018 ◽

Vol 65 (2) ◽

pp. 164-173 ◽

Cited By ~ 13

Author(s):

Frederico Pieruccini-Faria ◽

Yanina Sarquis-Adamson ◽

Manuel Montero-Odasso

Keyword(s):

Older Adults ◽

Cognitive Impairment ◽

Executive Function ◽

Mild Cognitive Impairment ◽

Dual Task ◽

Gait Speed ◽

Step Length ◽

Gait Control ◽

Dual Tasking ◽

Brain Study

Background: Older adults with Mild Cognitive Impairment (MCI) are at higher risk of falls and injuries, but the underlying mechanism is poorly understood. Inappropriate anticipatory postural adjustments to overcome balance perturbations are affected by cognitive decline. However, it is unknown whether anticipatory gait control to avoid an obstacle is affected in MCI. Objective: Using the dual-task paradigm, we aim to assess whether gait control is affected during obstacle negotiation challenges in older adults with MCI. Methods: Seventy-nine participants (mean age = 72.0 ± 2.7 years; women = 30.3%) from the “Gait and Brain Study” were included in this study (controls = 27; MCI = 52). In order to assess the anticipatory control behaviour for obstacle negotiation, a 6-m electronic walkway embedded with sensors recorded foot prints to measure gait speed and step length variability, during early (3 steps before the late phase) and late (3 steps before the obstacle) pre-crossing phases of an ad hoc obstacle, set at 15% of participant’s height. Participants walked under single- and dual-task gait (counting backwards by 1’s from 100 while walking) conditions. Three-way mixed repeated-measures analysis of variance models examined differences in gait performance between groups when transitioning between pre-crossing phases towards an obstacle during single- and dual-task conditions. Analyses were adjusted for age, sex, years of education, lower limb function, fear of falling, medical status, depressive symptoms, baseline gait speed and executive function. Results: A significant three-way interaction among groups, pre-crossing phases and task showed that participants with MCI attenuated the gait deceleration (p = 0.02) and performed fewer step length adjustments (p = 0.03) when approaching the obstacle compared with controls while dual-tasking. These interactions were attenuated when executive function performance was added as a covariate in the adjusted statistical model. Conclusion: Older adults with MCI attenuate the anticipatory gait adjustments needed to avoid an obstacle when dual-tasking. Deficits in higher-order cognitive processing may limit obstacle negotiation capabilities in MCI populations, being a potential falls risk factor.

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Predicting Age-Related Dual-Task Effects With Individual Differences on Neuropsychological Tests.

Neuropsychology ◽

10.1037/0894-4105.19.1.18 ◽

2005 ◽

Vol 19 (1) ◽

pp. 18-27 ◽

Cited By ~ 42

Author(s):

Roee Holtzer ◽

Yaakov Stern ◽

Brian C. Rakitin

Keyword(s):

Individual Differences ◽

Dual Task ◽

Neuropsychological Tests ◽

Task Effects ◽

Age Related

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Association Between Dual-Task Gait and Cognitive Function in Older Adults

Innovation in Aging ◽

10.1093/geroni/igab046.617 ◽

2021 ◽

Vol 5 (Supplement_1) ◽

pp. 162-162

Author(s):

Jessie VanSwearingen ◽

Mark Redfern ◽

Ervin Sejdic ◽

Andrea Rosso ◽

Anisha Suri

Keyword(s):

Older Adults ◽

Executive Function ◽

Cognitive Function ◽

Dual Task ◽

Task Effects ◽

Community Mobility ◽

Gait Quality ◽

Z Scores ◽

Global Cognition ◽

Pearson Correlations

Abstract Community mobility involves walking with physical and cognitive challenges. In older adults (N=116; results here from initial analyses: N=29, Age=75±5 years, 51% females), we assessed gait speed and smoothness (harmonic-ratio) while walking on even and uneven surfaces, with or without an alternate alphabeting dual-task (ABC). ANOVA assessed surface and dual-task effects; Pearson correlations compared gait with global cognition and executive function composite z-scores. The four conditions (even, uneven, even-ABC and uneven-ABC) affected speed(m/s) (0.97±0.14 vs 0.90±0.15 vs 0.83±0.17 vs 0.79±0.16). Smoothness (2.19±0.48 vs 1.89±0.38 vs 1.92±0.53 vs 1.7±0.43) was affected by only surface (controlled for speed). Greater speed was associated with better global cognition(ρ=0.47 to 0.49, p<0.05) for all conditions and with better executive function for even-ABC(ρ=0.39, p=0.04) and uneven-ABC(ρ=0.40, p=0.03). Executive function was associated with smoothness during even(ρp=-0.42, p=0.03) and uneven(ρp=-0.39, p=0.04) walking. Type of walking challenge differentially affects gait quality and associations with cognitive function.

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Prefrontal Cortex Activity During Walking: Effects of Aging and Associations With Gait and Executive Function

Neurorehabilitation and Neural Repair ◽

10.1177/1545968320953824 ◽

2020 ◽

Vol 34 (10) ◽

pp. 915-924 ◽

Cited By ~ 1

Author(s):

Priscila Nóbrega-Sousa ◽

Lilian Teresa Bucken Gobbi ◽

Diego Orcioli-Silva ◽

Núbia Ribeiro da Conceição ◽

Victor Spiandor Beretta ◽

...

Keyword(s):

Prefrontal Cortex ◽

Executive Function ◽

Dual Task ◽

Compensatory Mechanism ◽

Functional Near Infrared Spectroscopy ◽

Obstacle Crossing ◽

Age Related ◽

Gait Parameters ◽

Effects Of Aging ◽

Gait Impairments

Background Declines in gait parameters are common with aging and more pronounced in tasks with increased executive demand. However, the neural correlates of age-related gait impairments are not fully understood yet. Objectives To investigate ( a) the effects of aging on prefrontal cortex (PFC) activity and gait parameters during usual walking, obstacle crossing and dual-task walking and ( b) the association between PFC activity and measures of gait and executive function. Methods Eighty-eight healthy individuals were distributed into 6 age-groups: 20-25 (G20), 30-35 (G30), 40-45 (G40), 50-55 (G50), 60-65 (G60), and 70-75 years (G70). Participants walked overground under 3 conditions: usual walking, obstacle crossing, and dual-task walking. Changes in oxygenated and deoxygenated hemoglobin in the PFC were recorded using functional near-infrared spectroscopy. Gait spatiotemporal parameters were assessed using an electronic walkway. Executive function was assessed through validated tests. Results Between-group differences on PFC activity were observed for all conditions. Multiple groups (ie, G30, G50, G60, and G70) showed increased PFC activity in at least one of the walking conditions. Young adults (G20 and G30) had the lowest levels of PFC activity while G60 had the highest levels. Only G70 showed reduced executive function and gait impairments (which were more pronounced during obstacle crossing and dual-task walking). PFC activity was related to gait and executive function. Conclusions Aging causes a gradual increase in PFC activity during walking. This compensatory mechanism may reach the resource ceiling in the 70s, when reduced executive function limits its efficiency and gait impairments are observed.

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What affects the magnitude of age-related dual-task costs in working memory? The role of stimulus domain and access to semantic representations

Quarterly Journal of Experimental Psychology ◽

10.1177/1747021820970744 ◽

2020 ◽

pp. 174702182097074

Author(s):

Agnieszka J Jaroslawska ◽

Stephen Rhodes ◽

Clément Belletier ◽

Jason M Doherty ◽

Nelson Cowan ◽

...

Keyword(s):

Older Adults ◽

Working Memory ◽

Dual Task ◽

Memory Task ◽

Semantic Representations ◽

Younger Adults ◽

Task Effects ◽

Concurrent Processing ◽

Age Related

Although there is evidence that the effect of including a concurrent processing demand on the storage of information in working memory is disproportionately larger for older than younger adults, not all studies show this age-related impairment, and the critical factors responsible for any such impairment remain elusive. Here we assess whether domain overlap between storage and processing activities, and access to semantic representations, are important determinants of performance in a sample of younger and older adults ( N = 119). We developed four versions of a processing task by manipulating the type of stimuli involved (either verbal or non-verbal) and the decision that participants had to make about the stimuli presented on the screen. Participants either had to perform a spatial judgement, in deciding whether the verbal or non-verbal item was presented above or below the centre of the screen, or a semantic judgement, in deciding whether the stimulus refers to something living or not living. The memory task was serial-ordered recall of visually presented letters. The study revealed a large increase in age-related memory differences when concurrent processing was required. These differences were smaller when storage and processing activities both used verbal materials. Dual-task effects on processing were also disproportionate for older adults. Age differences in processing performance appeared larger for tasks requiring spatial decisions rather than semantic decisions. We discuss these findings in relation to three competing frameworks of working memory and the extant literature on cognitive ageing.

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Dual-Task Costs in Gait Speed Differs Across Age Groups

Innovation in Aging ◽

10.1093/geroni/igab046.3243 ◽

2021 ◽

Vol 5 (Supplement_1) ◽

pp. 901-901

Author(s):

Sally Paulson ◽

Michelle Gray ◽

Joshua Gills ◽

Anthony Campitelli ◽

Megan Jones ◽

...

Keyword(s):

Dual Task ◽

Gait Speed ◽

Oldest Old ◽

Age Groups ◽

Arithmetic Task ◽

Age Related ◽

Significant Difference ◽

Dual Task Cost ◽

Young Old ◽

Secondary Stimulus

Abstract With age, there are simultaneous reductions in gait speed (GS). This decrease in GS has been associated with an increased fall risk and negatively impacts independence. Further, GS naturally declines with the addition of a secondary stimulus (i.e., cognitive requirements). Combined, these decrements can be additive in nature potentially leading to robust declines with advancing age. Therefore, the aim of this study was to examine age-related effects of dual-task cost (DTC) while walking. Adults (N = 145), over the age of 45 years, completed two walking trials for each GS condition: habitual (HAB) and fast (FST), with and without a DT (i.e., counting backwards by serials of three). Subjects were classified into four age groups: youngest-old (YG ≤ 64 years, n = 24), young-old (YO, 65-74 years, n = 46), middle-old (MO = 75-84 years, n = 54), and oldest-old (OO ≥ 85 years, n = 21). DTC was calculated and ANOVAs were used to assess differences between the groups. There was no difference in HAB DTC between the age groups (p=.61). However, there was a significant difference in FST DTC (p=.04) between the YO (M±SD: -14 ± -11%) and OO (M±SD: -24 ± -12%). These data indicate there was an age-related affect for fast dual-task cost, but not for habitual dual-task cost while walking. An increase in dual-task cost among the oldest-old may be associated with an inability to properly maintain a faster cadence while performing an arithmetic task which may be related to task prioritization.

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Effects of blueberry supplementation on measures of functional mobility in older adults

Applied Physiology Nutrition and Metabolism ◽

10.1139/apnm-2014-0247 ◽

2015 ◽

Vol 40 (6) ◽

pp. 543-549 ◽

Cited By ~ 15

Author(s):

Matthew A. Schrager ◽

James Hilton ◽

Richard Gould ◽

Valerie E. Kelly

Keyword(s):

Older Adults ◽

Executive Function ◽

Dual Task ◽

Gait Speed ◽

Mixed Model ◽

Model Analysis ◽

Functional Mobility ◽

Mixed Model Analysis ◽

Blueberry Supplementation ◽

Adaptive Gait

Limited functional mobility in older adults has been associated with declines in tests of motor, psychomotor, and executive function. Animal studies have demonstrated reversals in indices of motor and psychomotor function via supplementation with polyphenolic-rich foods such as blueberries. The purpose of this study was to examine whether 6 weeks of daily consumption of 2 cups of frozen blueberries affects functional mobility in older adults. Pre- and post-intervention assessments of grip strength, simple reaction time, adaptive gait, and executive function were completed for older adults (age >60 years) partially randomly assigned to a blueberry (BB) supplementation or a carrot juice drink control (CAR) group. Paired t tests were used to assess within-group effects for outcome variables in each supplementation group, and a mixed-model analysis of covariance (ANCOVA) was used to determine group (CAR vs. BB) differences. Mixed-model analysis indicated that the BB group demonstrated significant improvements relative to the CAR group in performance (i.e., number of step errors) of a challenging dual-task adaptive gait test that were independent of differences in gait speed. Within only the BB group, significant improvements were also seen in 3 other measures (i.e., usual gait speed; number of step errors during single-task adaptive gait; and gait speed during dual-task adaptive gait). These preliminary findings support the hypothesis that blueberry supplementation may provide an effective countermeasure to age-related declines in functional mobility and serve as justification for an expansion to larger trials to more fully assess this nonpharmacologic approach to maintaining optimal mobility and independence.

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Effects of Gait and Cognitive Task Difficulty on Cognitive-Motor Interference in Aging

Journal of Aging Research ◽

10.1155/2012/583894 ◽

2012 ◽

Vol 2012 ◽

pp. 1-8 ◽

Cited By ~ 29

Author(s):

Prudence Plummer-D'Amato ◽

Briana Brancato ◽

Mallory Dantowitz ◽

Stephanie Birken ◽

Christina Bonke ◽

...

Keyword(s):

Older Adults ◽

Dual Task ◽

Gait Speed ◽

Task Difficulty ◽

Cognitive Task ◽

Task Interference ◽

Significant Group ◽

Fast Speed ◽

Task Effects ◽

Dual Task Interference

Although gait-related dual-task interference in aging is well established, the effect of gait and cognitive task difficulty on dual-task interference is poorly understood. The purpose of this study was to examine the effect of gait and cognitive task difficulty on cognitive-motor interference in aging. Fifteen older adults (72.1 years, SD 5.2) and 20 young adults (21.7 years, SD 1.6) performed three walking tasks of varying difficulty (self-selected speed, fast speed, and fast speed with obstacle crossing) under single- and dual-task conditions. The cognitive tasks were the auditory Stroop task and the clock task. There was a significant Group×Gait Task×Cognitive Task interaction for the dual-task effect on gait speed. After adjusting for education, there were no significant effects of gait or cognitive task difficulty on the dual-task effects on cognitive task performance. The results of this study provide evidence that gait task difficulty influences dual-task effects on gait speed, especially in older adults. Moreover, the effects of gait task difficulty on dual-task interference appear to be influenced by the difficulty of the cognitive task. Education is an important factor influencing cognitive-motor interference effects on cognition, but not gait.

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