Association of health behaviors with function and health-related quality of life among patients with Parkinson's disease.

BACKGROUND: Current evidence on chronic conditions favors promotion of health behaviors as a mean to positively impact health outcomes. In Parkinson's disease, performing health behaviors is indicated as a means to fight the long-lasting burden of the disease. Understanding actual engagement in health behaviors and patient activation and their association to function and health-related quality of life is therefore important. Our objectives were, among people with Parkinson's disease: (1) to characterize health behaviors including utilization of rehabilitative treatments, physical activity, and patient activation levels, and (2) to test the associations between these health behaviors and health outcomes. METHODS: A cross-sectional study of 88 people with Parkinson's disease (age 66.84 ± 8.8) was conducted. Participants answered questionnaires measuring health behaviors including utilization of health professions treatments, physical activity, patient activation, and health outcomes consisting of function and health-related quality of life. Linear regression models were conducted to test associations between measured health behaviors, function and health-related quality of life. RESULTS: Participants rarely engage in rehabilitative treatments, but showed high levels of patient activation. Controlled by demographics and disease severity, physical activity and patient activation were associated with function (b = 0.41, p < .001; b = 0.2, p = .02, respectively) and physical activity but not patient activation, which was associated with health-related quality of life (b = 0.19, p = .03). There was also interaction effects of physical activity and non-motor symptoms, and physical activity and motor symptoms on health-related quality of life (b = 0.19, p = .02 and b = - 0.22, p = .01, respectively). CONCLUSIONS: In respect to their potential health-related benefits for people with Parkinson's disease, health professionals' treatments are underutilized. Findings supported the importance of health behaviors for maintaining function and health-related quality of life among people with Parkinson's disease. They also show a differential contribution of motor and non-motor symptoms to the association between physical activity and quality of life. It is suggested that policy makers encourage opportunities for physical activity tailored for people with Parkinson's disease and adopt a proactive stance towards enhancing awareness and use of rehabilitation services. Trial registration NCT05211700, ClinicalTrials.gov ID: NCT05211700 first release 12/30/2021, https://classic. CLINICALTRIALS: gov/ct2/show/NCT05211700.

Socio-Clinical factors associated with Parkinson's disease-related specific self-management behaviours.

OBJECTIVE: To test associations between socio-clinical factors, self-management and patient activation among patients with Parkinson's disease (PD), and to explore the use of regression tree to find the cut-off levels of socio-clinical factors which associate with lower or higher self-management behaviours and patient's activation. METHODS: A cross-sectional study of patients with PD (n = 62) who underwent assessment of their socio-clinical factors including age, gender, cognitive status, comorbidities, disease severity (motor and non-motor symptoms) and social support. The associations of these factors to specific aspects of self-management behaviours including utilization of rehabilitative treatments, physical activity and patient activation were tested. RESULTS: Most patients did not utilize rehabilitative treatments. Non-motor symptoms and cognitive status were significantly associated with physical activity (R2 = 0.35, F(3, 58) = 10.50, p < 0.001). Non-motor symptoms were significantly associated with patient activation (R2 = 0.30, F(1, 30) = 25.88, p < 0.001). Patients with Mini-Mental State Exam score ≤24 performed less physical activity, relative to those with a higher score. Patients with ≤5 non-motor symptoms showed higher activation relative to those with >5. CONCLUSION: In PD, disease-specific clinical characteristics overshadow other personal factors as determinants of self-management behaviours. The role of non-motor symptoms in reduced self-management behaviours and activation is highlighted.

The development of a home-based technology to improve gait in people with Parkinson's disease: a feasibility study.

BACKGROUND: People with Parkinson's disease (PwP) may experience gait impairment and freezing of gait (FOG), a major cause of falls. External cueing, including visual (e.g., spaced lines on the floor) and auditory (e.g., rhythmic metronome beats) stimuli, are considered effective in alleviating mobility deficits and FOG. Currently, there is a need for a technology that delivers automatic, individually adjusted cues in the homes of PwP. The aims of this feasibility study were to describe the first step toward the development of a home-based technology that delivers external cues, test its effect on gait, and assess user experience. METHODS: Iterative system development was performed by our multidisciplinary team. The system was designed to deliver visual and auditory cues: light stripes projected on the floor and metronome beats, separately. Initial testing was performed using the feedback of five healthy elderly individuals on the cues' clarity (clear visibility of the light stripes and the sound of metronome beats) and discomfort experienced. A pilot study was subsequently conducted in the homes of 15 PwP with daily FOG. We measured participants' walking under three conditions: baseline (with no cues), walking with light stripes, and walking to metronome beats. Outcome measures included step length and step time. User experience was also captured in semi-structured interviews. RESULTS: Repeated-measures ANOVA of gait assessment in PwP revealed that light stripes significantly improved step length (p = 0.009) and step time (p = 0.019) of PwP. No significant changes were measured in the metronome condition. PwP reported that both cueing modalities improved their gait, confidence, and stability. Most PwP did not report any discomfort in either modality and expressed a desire to have such a technology in their homes. The metronome was preferred by the majority of participants. CONCLUSIONS: This feasibility study demonstrated the usability and potential effect of a novel cueing technology on gait, and represents an important first step toward the development of a technology aimed to prevent FOG by delivering individually adjusted cues automatically. A further full-scale study is needed. Trial registration This study was registered in ClinicalTrials.gov at 1/2/2022 NCT05211687.

Occupational therapy for people with Parkinson's disease in Israel: A SWOT analysis.

BACKGROUND: Despite the important role that occupational therapy (OT) plays in management of Parkinson's disease (PD), few patients with PD in Israel seek such treatment. AIMS: To capture the opinions of internal and external (to the profession) informants regarding OT's role in the management of PD, to identify factors that may affect the utilization of OT, and to identify potential strategies for promoting such use. MATERIAL AND METHODS: Fifty-two occupational therapists and nine neurologists who specialize in movement disorders completed online questionnaires containing both closed and open-ended questions. An analysis of strengths, weaknesses, opportunities, and threats (SWOT) was performed on the responses, and text analyses were performed on the responses to the open-ended questions. RESULTS: Identified strengths included respondents' self-confidence in treating patients with PD, and collaboration with multidisciplinary teams. Weaknesses included lack of specific training, low frequency of seeing patients with PD, overlapping treatment objectives with other healthcare professions, and lack of familiarity with guidelines. Patients' and physicians' limited acquaintance with OT, and referral rates were acknowledged as both opportunities and threats. CONCLUSIONS/SIGNIFICANCE: Strategies for promoting the use of OT among Parkinson's patients include specific training and increased awareness of OT for referring physician and patients.

Compensatory movement strategies differentially affect attention allocation and gait parameters in persons with Parkinson's disease.

Persons with Parkinson's disease (PwP) are advised to use compensatory strategies such as external cues or cognitive movement strategies to overcome gait disturbances. It is suggested that external cues involve the processing of sensory stimulation, while cognitive-movement strategies use attention allocation. This study aimed to compare over time changes in attention allocation in PwP between prolonged walking with cognitive movement strategy and external cues; to compare the effect of cognitive movement strategies and external cues on gait parameters; and evaluate whether these changes depend on cognitive function. Eleven PwP participated in a single-group pilot study. Participants walked for 10 min under each of three conditions: natural walking, using external cuing, using a cognitive movement strategy. Attention and gait variables were extracted from a single-channel electroencephalogram and accelerometers recordings, respectively. Attention allocation was assessed by the% of Brain Engagement Index (BEI) signals within an attentive engagement range. Cognitive function was assessed using a neuropsychological battery. The walk was divided into 2-min time segments, and the results from each 2-min segment were used to determine the effects of time and condition. Associations between cognitive function and BEI signals were tested. Findings show that in the cognitive movement strategy condition, there was a reduction in the % of BEI signals within the attentive engagement range after the first 2 min of walking. Despite this reduction the BEI did not consistently differ from natural and metronome walking. Spatiotemporal gait variables were better in the cognitive movement strategy condition relative to the other conditions. Global cognitive and information processing scores were significantly associated with the BEI only when the cognitive movement strategy was applied. In conclusion, the study shows that a cognitive movement strategy has positive effects on gait variables but may impose a higher attentional load. Furthermore, when walking using a cognitive movement strategy, persons with higher cognitive function showed elevated attentive engagement. The findings support the idea that cognitive and attentional resources are required for cognitive movement strategies in PwP. Additionally, this study provides support for using single-channel EEG to explore mechanistic aspects of clinical interventions.

COVID-19 social distancing: negative effects on people with Parkinson disease and their associations with confidence for self-management.

BACKGROUND: The purpose of this study was to describe the effects of COVID-19 social distancing on the function, health, and well-being of people with Parkinson disease (PD), and test the association of these effects with patients' activation levels, i.e., their skills and confidence in managing their health. METHODS: Community-dwelling individuals with PD answered an anonymous web-based survey. Part 1 included 27 multiple-choice questions regarding changes in function, health, medical care, and well-being. Part 2 consisted of the Patient Activation Measure, which enquired about skills and confidence in managing one's health. RESULTS: Respondents (N = 142) reported decreases in various function (24.8%-37.3%), health (33.8%-43%), and well-being (26.1%-47.1%) domains. Rehabilitation ceased for 61.2%. Among those reporting a worsening of health, 67.8% associated this with the cessation of rehabilitative treatments or decrease in physical activity. Patients' activation levels were inversely correlated with increased assistance for activities of daily living, increased tiredness, worsening symptoms, and lack of support from family and friends. CONCLUSIONS: Social distancing had a major negative impact on the health and function of people with PD. PRACTICAL IMPLICATIONS: Supporting people with PD skills and confidence in managing health may preserve their physical and mental health during this period of dramatic changes in life's circumstances.

Neurocognitive Plasticity Is Associated with Cardiorespiratory Fitness Following Physical Exercise in Older Adults with Amnestic Mild Cognitive Impairment.

BACKGROUND: Aerobic training has been shown to promote structural and functional neurocognitive plasticity in cognitively intact older adults. However, little is known about the neuroplastic potential of aerobic exercise in individuals at risk of Alzheimer's disease (AD) and dementia. OBJECTIVE: We aimed to explore the effect of aerobic exercise intervention and cardiorespiratory fitness improvement on brain and cognitive functions in older adults with amnestic mild cognitive impairment (aMCI). METHODS: 27 participants with aMCI were randomized to either aerobic training (n = 13) or balance and toning (BAT) control group (n = 14) for a 16-week intervention. Pre- and post-assessments included functional MRI experiments of brain activation during associative memory encoding and neural synchronization during complex information processing, cognitive evaluation using neuropsychological tests, and cardiorespiratory fitness assessment. RESULTS: The aerobic group demonstrated increased frontal activity during memory encoding and increased neural synchronization in higher-order cognitive regions such as the frontal cortex and temporo-parietal junction (TPJ) following the intervention. In contrast, the BAT control group demonstrated decreased brain activity during memory encoding, primarily in occipital, temporal, and parietal areas. Increases in cardiorespiratory fitness were associated with increases in brain activationin both the left inferior frontal and precentral gyri. Furthermore, changes in cardiorespiratory fitness were also correlated with changes in performance on several neuropsychological tests. CONCLUSION: Aerobic exercise training may result in functional plasticity of high-order cognitive areas, especially, frontal regions, among older adults at risk of AD and dementia. Furthermore, cardiorespiratory fitness may be an important mediating factor of the observed changes in neurocognitive functions.

Maximal aerobic capacity is associated with hippocampal cognitive reserve in older adults with amnestic mild cognitive impairment.

Maximal aerobic capacity (MAC) has been associated with preserved neural tissue or brain maintenance (BM) in healthy older adults, including the hippocampus. Amnestic mild cognitive impairment (aMCI) is considered a prodromal stage of Alzheimer's disease. While aMCI is characterized by hippocampal deterioration, the MAC-hippocampal relationship in these patients is not well understood. In contrast to healthy individuals, neurocognitive protective effects in neurodegenerative populations have been associated with mechanisms of cognitive reserve (CR) altering the neuropathology-cognition relationship. We investigated the MAC-hippocampal relationship in aMCI (n = 29) from the perspectives of BM and CR mechanistic models with structural MRI and a memory fMRI paradigm using both group-level (higher-fit patients vs. lower-fit patients) and individual level (continuous correlation) approaches. While MAC was associated with smaller hippocampal volume, contradicting the BM model, higher-fit patients demonstrated statistically significant lower correlation between hippocampal volume and memory performance compared with the lower-fit patients, supporting the model of CR. In addition, while there was no difference in brain activity between the groups during low cognitive demand (encoding of familiar stimuli), higher MAC level was associated with increased cortical and sub-cortical activation during increased cognitive demand (encoding of novel stimuli) and also with bilateral hippocampal activity even when controlling for hippocampal volume, suggesting for an independent effect of MAC. Our results suggest that MAC may be associated with hippocampal-related cognitive reserve in aMCI through altering the relationship between hippocampal-related structural deterioration and cognitive function. In addition, MAC was found to be associated with increased capacity to recruit neural resources during increased cognitive demands.

Abnormal neural hierarchy in processing of verbal information in patients with schizophrenia.

Previous research indicates abnormal comprehension of verbal information in patients with schizophrenia. Yet the neural mechanism underlying the breakdown of verbal information processing in schizophrenia is poorly understood. Imaging studies in healthy populations have shown a network of brain areas involved in hierarchical processing of verbal information over time. Here, we identified critical aspects of this hierarchy, examining patients with schizophrenia. Using functional magnetic resonance imaging, we examined various levels of information comprehension elicited by naturally presented verbal stimuli; from a set of randomly shuffled words to an intact story. Specifically, patients with first episode schizophrenia (N = 15), their non-manifesting siblings (N = 14) and healthy controls (N = 15) listened to a narrated story and randomly scrambled versions of it. To quantify the degree of dissimilarity between the groups, we adopted an inter-subject correlation (inter-SC) approach, which estimates differences in synchronization of neural responses within and between groups. The temporal topography found in healthy and siblings groups were consistent with our previous findings - high synchronization in responses from early sensory toward high order perceptual and cognitive areas. In patients with schizophrenia, stimuli with short and intermediate temporal scales evoked a typical pattern of reliable responses, whereas story condition (long temporal scale) revealed robust and widespread disruption of the inter-SCs. In addition, the more similar the neural activity of patients with schizophrenia was to the average response in the healthy group, the less severe the positive symptoms of the patients. Our findings suggest that system-level neural indication of abnormal verbal information processing in schizophrenia reflects disease manifestations.

The Effect of External and Internal Focus of Attention on Gait Variability in Older Adults.

Internal focus of attention on a movement or focusing on an external target are both strategies that can affect motor performance. The authors explored whether manipulating subjects' focus of attention while walking would alter gait variability, a measure reflecting consistency of gait and associated with the risk of falling in older adults. Twenty community-living older adults participated in the study and were tested while focusing their attention on (a) gait consistency (internal focus) or (b) metronome beats (external focus). In both conditions gait variability increased (i.e., worsened p < .05) or did not change. No benefit was found in instructing subjects to focus on gait consistency or metronome beats. Such instructions may actually have distracted and interfered with the execution of gait.

Altered Topology in Information Processing of a Narrated Story in Older Adults with Mild Cognitive Impairment.

The ability to store, integrate, and manipulate information declines with aging. These changes occur earlier, faster, and to a greater degree as a result of neurodegeneration. One of the most common and early characteristics of cognitive decline is difficulty with comprehension of information. The neural mechanisms underlying this breakdown of information processing are poorly understood. Using functional MRI and natural stimuli (e.g., stories), we mapped the neural mechanisms by which the human brain accumulates and processes information with increasing duration and complexity in participants with amnestic mild cognitive impairment (aMCI) and healthy older adults. To explore the mechanisms of information processing, we measured the reliability of brain responses elicited by listening to different versions of a narrated story created by segmenting the story into words, sentences, and paragraphs and then scrambling the segments. Comparing healthy older adults and participants with aMCI revealed that in both groups, all types of stimuli similarly recruited primary auditory areas. However, prominent differences between groups were found at the level of processing long and complex stimuli. In healthy older adults, parietal and frontal regions demonstrated highly synchronized responses in both the paragraph and full story conditions, as has been previously reported in young adults. Participants with aMCI, however, exhibited a robust functional shift of long time scale processing to the pre- and post-central sulci. Our results suggest that participants with aMCI experienced a functional shift of higher order auditory information processing, possibly reflecting a functional response to concurrent or impending neuronal or synaptic loss. This observation might assist in understanding mechanisms of cognitive decline in aMCI.

Validity of the Kinect for Gait Assessment: A Focused Review.

Gait analysis may enhance clinical practice. However, its use is limited due to the need for expensive equipment which is not always available in clinical settings. Recent evidence suggests that Microsoft Kinect may provide a low cost gait analysis method. The purpose of this report is to critically evaluate the literature describing the concurrent validity of using the Kinect as a gait analysis instrument. An online search of PubMed, CINAHL, and ProQuest databases was performed. Included were studies in which walking was assessed with the Kinect and another gold standard device, and consisted of at least one numerical finding of spatiotemporal or kinematic measures. Our search identified 366 papers, from which 12 relevant studies were retrieved. The results demonstrate that the Kinect is valid only for some spatiotemporal gait parameters. Although the kinematic parameters measured by the Kinect followed the trend of the joint trajectories, they showed poor validity and large errors. In conclusion, the Kinect may have the potential to be used as a tool for measuring spatiotemporal aspects of gait, yet standardized methods should be established, and future examinations with both healthy subjects and clinical participants are required in order to integrate the Kinect as a clinical gait analysis tool.

The Montreal Cognitive Assessment in cognitively-intact elderly: a case for age-adjusted cutoffs.

The Montreal Cognitive Assessment (MoCA) is a widely used screening test for evaluation of mild cognitive impairment (MCI), with a single cutoff for all ages. We examined whether it is associated with age in a sample of cognitively-intact elderly (CIE). The average MoCA score was negatively correlated with age and was significantly higher for younger than older CIE. Additionally, 42% of the older elderly fell below the proposed MCI cutoff score, although all subjects were CIE. Thus, cognitive abilities captured by the MoCA test decrease with age, even in CIE. Therefore, cutoff scores by age for the MoCA are needed.

The contribution of postural control and bilateral coordination to the impact of dual tasking on gait.

The simultaneous performance of a cognitive task while walking typically alters the gait pattern. In some populations, these alterations have been associated with an increased risk of falls, motivating study of this response from the clinical perspective. The mechanisms responsible for these effects are not fully understood. The concurrent requirement to control upright posture and stepping, a bilaterally coordinated rhythmic task, may be the cause of this so-called dual-tasking effect. To evaluate this possibility, the present study was designed to isolate the individual contribution of these two demands by assessing the effects of cognitive loading on standing (i.e., postural control without bilateral coordination of stepping), cycling (i.e., bilateral coordination similar to stepping, but with minimal postural demands), and walking. We also investigated the effects of aging and parkinsonism on the performance of these three tasks in response to cognitive loading, also referred to as a dual task. Twenty-one healthy young adults, 15 healthy older adults, and 18 patients with Parkinson's disease were assessed while walking, standing, and cycling, with and without an additional cognitive load. In the young adults, the performance on the two motor tasks that involved bilateral coordination deteriorated significantly in response to the dual task, while standing was not impacted. Similar results, although less robust, were observed among the healthy older adults. In contrast, among the patients with Parkinson's disease, the dual-task costs, i.e., the impact of the simultaneously performed cognitive task on the gait pattern, were high in all motor tasks. These findings suggest that walking is especially vulnerable to cognitive loading, in part, because of the unique sensitivity of bilateral coordination of limb movements to the effects of dual tasking.

Do we always prioritize balance when walking? Towards an integrated model of task prioritization.

Previous studies suggest that strategies such as "posture first" are implicitly employed to regulate safety when healthy adults walk while simultaneously performing another task, whereas "posture second" may be inappropriately applied in the presence of neurological disease. However, recent understandings raise questions about the traditional resource allocation concept during walking while dual tasking. We propose a task prioritization model of walking while dual tasking that integrates motor and cognitive capabilities, focusing on postural reserve, hazard estimation, and other individual intrinsic factors. The proposed prioritization model provides a theoretical foundation for future studies and a framework for the development of interventions designed to reduce the profound negative impacts of dual tasking on gait and fall risk in patients with neurological diseases. © 2012 Movement Disorder Society.

Effects of explicit prioritization on dual task walking in patients with Parkinson's disease.

Patients with Parkinson's disease (PD) have difficulties performing a dual task (DT) while walking and may use the "posture second" strategy. It is not clear if this is a result of motor or cognitive impairments. We examined the effects of explicit prioritization of walking or the cognitive task on gait speed (GS) and variability in 20 patients (Hoehn & Yahr stage: 2.3 ± 0.5) and 20 healthy older adults during usual-walking and under three DT (verbal-fluency) conditions: (1) no instruction for prioritization, (2) specific attention to the walking pattern (gait prioritization), and (3) specific attention to the cognitive task (prioritization of verbal-fluency). The Montreal Cognitive Assessment, the Frontal Assessment Battery, and the Trail Making Tests assessed cognitive status. The two groups did not differ on these cognitive tests. Compared to usual-walking, all subjects reduced their GS in the un-instructed DT condition. Compared to the un-instructed DT condition, both groups significantly (p < 0.001) increased GS when prioritizing walking and maintained about the same GS when prioritizing the cognitive task (p > 0.155). All three DT conditions increased gait variability in both groups (p < 0.001 usual-walking compared to uninstructed DT). Verbal-fluency tended (p = 0.073) to be influenced by prioritization in both groups. Task prioritization abilities were similar in the patients and controls, even though the patients generally walked more slowly. PD patients without cognitive impairment apparently utilize their cognitive resources in the same manner as healthy older adults. Both groups, however, use some form of the posture second strategy and naturally focus on the cognitive task.

A training program to improve gait while dual tasking in patients with Parkinson's disease: a pilot study.

Impairments in the ability to perform another task while walking (ie, dual tasking [DT]) are associated with an increased risk of falling. Here we describe a program we developed specifically to improve DT performance while walking based on motor learning principles and task-specific training. We examined feasibility, potential efficacy, retention, and transfer to the performance of untrained tasks in a pilot study among 7 patients with Parkinson's disease (PD). Seven patients (Hoehn and Yahr stage, 2.1±0.2) were evaluated before, after, and 1 month after 4 weeks of DT training. Gait speed and gait variability were measured during usual walking and during 4 DT conditions. The 4-week program of one-on-one training included walking while performing several distinct cognitive tasks. Gait speed and gait variability during DT significantly improved. Improvements were also seen in the DT conditions that were not specifically trained and were retained 1 month after training. These initial findings support the feasibility of applying a task-specific DT gait training program for patients with PD and suggest that it positively affects DT gait, even in untrained tasks. The present results are also consistent with the possibility that DT gait training enhances divided attention abilities during walking.

The interplay between gait, falls and cognition: can cognitive therapy reduce fall risk?

In this article, we briefly summarize the incidence and significant consequences of falls among older adults, the insufficient effectiveness of commonly used multifactorial interventions and the evidence linking falls and cognitive function. Recent pharmacologic and nonpharmacologic studies that evaluated the effects of cognitive therapy on fall risk are reviewed. The results of this article illustrate the potential utility of multiple, diverse forms of cognitive therapy for reducing fall risk. The article also indicates that large-scale, randomized controlled trials are warranted and that additional research is needed to better understand the pathophysiologic mechanisms underlying the interplay between human mobility, fall risk and cognitive function. Nonetheless, we suggest that multimodality interventions that combine motor and cognitive therapy should, eventually, be incorporated into clinical practice to enable older adults and patients to move safer and with a reduced fall risk.

How does explicit prioritization alter walking during dual-task performance? Effects of age and sex on gait speed and variability.

BACKGROUND: Previous studies have demonstrated that the performance of a secondary task during walking alters gait. OBJECTIVE: This study investigated the effects of task prioritization on walking in young and older adults to evaluate the "default" prioritization scheme used, the flexibility to alter prioritization and cortical resources allocated to gait and a secondary cognitive task, and any age-associated changes in these abilities. DESIGN: A cross-sectional study that explicitly altered the focus of attention was used to investigate the effects of prioritization in young and older adults who were healthy. METHODS: Gait speed and gait variability were evaluated in young adults (n=40) and older adults (n=17) who were healthy, both during usual walking and under 3 dual-task conditions: (1) no specific prioritization instructions, (2) prioritization of gait, and (3) prioritization of the cognitive task. RESULTS: Young adults significantly increased gait speed in the gait prioritization condition compared with gait speed in the no-instruction condition; a similar tendency was seen in the older adults. Gait speed was reduced when priority was given to the cognitive task in both age groups; however, this effect was less dramatic in the older adults. In the young adults, prioritization of gait tended to have different effects on gait speed among both men and women. In the older adults, but not in the young adults, all dual-task conditions produced increased gait variability, whereas prioritization did not alter this gait feature. LIMITATIONS: The sample size and the relative homogeneity of the older adults could be considered as possible limitations of the study. CONCLUSIONS: Even among young adults, the effects of secondary, cognitive tasks on gait speed are strongly influenced by prioritization. This finding was less significant in the older adults, suggesting that there is an age-associated decline in the ability to flexibly allocate attention to gait. Somewhat surprisingly, when prioritization was not explicitly instructed, gait speed in both young and older adults most closely resembled that of the condition when they were instructed to focus attention on the cognitive task.

Dual-task decrements in gait: contributing factors among healthy older adults.

BACKGROUND: The factors that contribute to the dual tasking (DT) changes in performance that occur when older adults walk while simultaneously performing other tasks are not well known. We hypothesized that cognitive and motor reserve (e.g., executive function [EF], postural control, and walking abilities) and affect (e.g., anxiety, depressive symptoms) influence the DT decrements (DTDs) in gait. METHODS: Two hundred twenty-eight community-living, healthy older adults (mean: 76.2 +/- 4.2 years; 59% women) walked with and without DT, for example, subtracting 7s and phoneme monitoring. Mobility (e.g., the Dynamic Gait Index), cognitive function (e.g., memory, EF), and affect (e.g., Geriatric Depression Scale) were quantified. Bivariate and multivariate analyses identified factors associated with the DTD in gait speed (a general measure of locomotor function), swing time, (reflecting balance during gait), and swing time variability (a measure of stride-to-stride consistency). RESULTS: Gait speed and swing time decreased (p <.001) and swing time variability increased (became worse) (p <.001) during all DTs. The DTD in gait speed was correlated with comfortable walking gait speed, but not with tests of mobility or cognitive function. The DTD in swing time variability was correlated with EF, mobility, and affect (e.g., depressive symptoms). Much of the variance in the DTDs was unexplained. CONCLUSIONS: Usual walking abilities and cognitive function contribute to the DT effects on gait, but these relationships depend on specifics of the DT, the gait feature being studied, and the particulars of the cognitive domain. Meeting the everyday challenges of walking while dual tasking apparently relies on multiple factors including a consistent gait pattern and EF.