Electrocortical Dynamics of Usual Walking and the Planning to Step over Obstacles in Parkinson's Disease.

The neural correlates of locomotion impairments observed in people with Parkinson's disease (PD) are not fully understood. We investigated whether people with PD present distinct brain electrocortical activity during usual walking and the approach phase of obstacle avoidance when compared to healthy individuals. Fifteen people with PD and fourteen older adults walked overground in two conditions: usual walking and obstacle crossing. Scalp electroencephalography (EEG) was recorded using a mobile 64-channel EEG system. Independent components were clustered using a k-means clustering algorithm. Outcome measures included absolute power in several frequency bands and alpha/beta ratio. During the usual walk, people with PD presented a greater alpha/beta ratio in the left sensorimotor cortex than healthy individuals. While approaching obstacles, both groups reduced alpha and beta power in the premotor and right sensorimotor cortices (balance demand) and increased gamma power in the primary visual cortex (visual demand). Only people with PD reduced alpha power and alpha/beta ratio in the left sensorimotor cortex when approaching obstacles. These findings suggest that PD affects the cortical control of usual walking, leading to a greater proportion of low-frequency (alpha) neuronal firing in the sensorimotor cortex. Moreover, the planning for obstacle avoidance changes the electrocortical dynamics associated with increased balance and visual demands. People with PD rely on increased sensorimotor integration to modulate locomotion.

Saccade and Fixation Eye Movements During Walking in People With Mild Traumatic Brain Injury.

Background: Clinical and laboratory assessment of people with mild traumatic brain injury (mTBI) indicate impairments in eye movements. These tests are typically done in a static, seated position. Recently, the use of mobile eye-tracking systems has been proposed to quantify subtle deficits in eye movements and visual sampling during different tasks. However, the impact of mTBI on eye movements during functional tasks such as walking remains unknown. Objective: Evaluate differences in eye-tracking measures collected during gait between healthy controls (HC) and patients in the sub-acute stages of mTBI recovery and to determine if there are associations between eye-tracking measures and gait speed. Methods: Thirty-seven HC participants and 67individuals with mTBI were instructed to walk back and forth over 10-m, at a comfortable self-selected speed. A single 1-min trial was performed. Eye-tracking measures were recorded using a mobile eye-tracking system (head-mounted infra-red Tobbii Pro Glasses 2, 100 Hz, Tobii Technology Inc. VA, United States). Eye-tracking measures included saccadic (frequency, mean and peak velocity, duration and distance) and fixation measurements (frequency and duration). Gait was assessed using six inertial sensors (both feet, sternum, right wrist, lumbar vertebrae and the forehead) and gait velocity was selected as the primary outcome. General linear model was used to compare the groups and association between gait and eye-tracking outcomes were explored using partial correlations. Results: Individuals with mTBI showed significantly reduced saccade frequency (p = 0.016), duration (p = 0.028) and peak velocity (p = 0.032) compared to the HC group. No significant differences between groups were observed for the saccade distance, fixation measures and gait velocity (p > 0.05). A positive correlation was observed between saccade duration and gait velocity only for participants with mTBI (p = 0.025). Conclusion: Findings suggest impaired saccadic eye movement, but not fixations, during walking in individuals with mTBI. These findings have implications in real-world function including return to sport for athletes and return to duty for military service members. Future research should investigate whether or not saccade outcomes are influenced by the time after the trauma and rehabilitation.

Aerobic Exercise Combined With Transcranial Direct Current Stimulation Over the Prefrontal Cortex in Parkinson Disease: Effects on Cortical Activity, Gait, and Cognition.

BACKGROUND: Since people with Parkinson disease (PD) rely on limited prefrontal executive resources for the control of gait, interventions targeting the prefrontal cortex (PFC) may help in managing PD-related gait impairments. Transcranial direct current stimulation (tDCS) can be used to modulate PFC excitability and improve prefrontal cognitive functions and gait. OBJECTIVE: We investigated the effects of adding anodal tDCS applied over the PFC to a session of aerobic exercise on gait, cognition, and PFC activity while walking in people with PD. METHODS: A total of 20 people with PD participated in this randomized, double-blinded, sham-controlled crossover study. Participants attended two 30-minute sessions of aerobic exercise (cycling at moderate intensity) combined with different tDCS conditions (active- or sham-tDCS), 1 week apart. The order of sessions was counterbalanced across the sample. Anodal tDCS (2 mA for 20 minutes [active-tDCS] or 10 s [sham-tDCS]) targeted the PFC in the most affected hemisphere. Spatiotemporal gait parameters, cognitive functions, and PFC activity while walking were assessed before and immediately after each session. RESULTS: Compared with the pre-assessment, participants decreased step time variability (effect size: -0.4), shortened simple and choice reaction times (effect sizes: -0.73 and -0.57, respectively), and increased PFC activity in the stimulated hemisphere while walking (effect size: 0.54) only after aerobic exercise + active-tDCS. CONCLUSION: The addition of anodal tDCS over the PFC to a session of aerobic exercise led to immediate positive effects on gait variability, processing speed, and executive control of walking in people with PD.

Effect of different types of exercises on psychological and cognitive features in people with Parkinson's disease: A randomized controlled trial.

BACKGROUND: Parkinson's disease (PD) is a neurodegenerative and progressive disease marked by the presence of motor and non-motor symptoms, as psychological and cognitive impairment. Physical exercises have been prescribed as complementary therapy for PD, and the type of intervention and duration of the intervention should be taken into account. OBJECTIVE: We aimed to compare the effect of different exercise modalities (functional mobility, multimodal and cognitive) and length (4 and 8 months) on psychological and cognition in people with PD. This study followed the CONSORT extension for non-pharmacological trials. METHODS: In this randomized controlled trial, we assessed 107 participants between 2011 and 2013. At the end of 3 years, participants with PD (mild to moderate stages) who achieved the criteria were assessed considering 3 different groups of exercise: Multimodal (n=38), Functional Mobility (n=33) and Mental/Leisure (n=36). All 3 interventions were performed for 32 weeks, twice a week, with 60min for each session (64 sessions in total). Psychological and cognitive function were assessed at baseline and after 4 and 8 months. RESULTS: The Functional Mobility and Mental/Leisure training had a potential effect on maintaining cognitive function (executive function, attention and work memory). The Multimodal training did not show a benefit for cognitive features and was not even able to delay the progressive decline in cognitive functions; however, this modality had a positive effect on physical stress after 8 months of exercise. CONCLUSIONS: An intervention that requires high complexity and specific activities, such as locomotor and cognitive exercise, provides a maintenance effect against the degeneration in cognition associated with the progression of PD and thus can delay the progressive decline in cognitive function in PD.

Levodopa Facilitates Prefrontal Cortex Activation During Dual Task Walking in Parkinson Disease.

Background. Although dopaminergic medication improves dual task walking in people with Parkinson disease (PD), the underlying neural mechanisms are not yet fully understood. As prefrontal cognitive resources are involved in dual task walking, evaluation of the prefrontal cortex (PFC) is required. Objective. To investigate the effect of dopaminergic medication on PFC activity and gait parameters during dual task walking in people with PD. Methods. A total of 20 individuals with PD (69.8 ± 5.9 years) and 30 healthy older people (68.0 ± 5.6 years) performed 2 walking conditions: single and dual task (walking while performing a digit vigilance task). A mobile functional near infrared spectroscopy system and an electronic sensor carpet were used to analyze PFC activation and gait parameters, respectively. Relative concentrations of oxygenated hemoglobin (HbO2) from the left and right PFC were measured. Results. People with PD in the off state did not present changes in HbO2 level in the left PFC across walking conditions. In contrast, in the on state, they presented increased HbO2 levels during dual task compared with single task. Regardless of medication state, people with PD presented increased HbO2 levels in the right PFC during dual task walking compared with single task. The control group demonstrated increased PFC activity in both hemispheres during dual task compared with single task. People with PD showed increases in both step length and velocity in the on state compared with the off state. Conclusions. PD limits the activation of the left PFC during dual task walking, and dopaminergic medication facilitates its recruitment.

Double obstacles increase gait asymmetry during obstacle crossing in people with Parkinson's disease and healthy older adults: A pilot study.

Gait asymmetry during unobstructed walking in people with Parkinson's disease (PD) has been well documented. However, under complex situations, such as environments with double obstacles, gait asymmetry remains poorly understood in PD. Therefore, the aim of this study was to analyze inter-limb asymmetry while crossing a single obstacle and double obstacles (with different distances between them) in people with PD and healthy older adults. Nineteen people with PD and 19 healthy older people performed three conditions: (i) walking with one obstacle (Single); (ii) walking with two obstacles with a 50 cm distance between them (Double-50); (iii) walking with two obstacles with a 108 cm distance between them (Double-108). The participants performed the obstacle crossing with both lower limbs. Asymmetry Index was calculated. We found that people with PD presented higher leading and trailing toe clearance asymmetry than healthy older people. In addition, participants increased asymmetry in the Double-50 compared to Single condition. It can be concluded that people with PD show higher asymmetry during obstacle crossing compared to healthy older people, independently of the number of obstacles. In addition, a challenging environment induces asymmetry during obstacle crossing in both people with PD and healthy older people.

Usual walking and obstacle avoidance are influenced by depressive and anxiety symptoms in patients with Parkinson's disease.

AIM: The aim of the present study was to analyze the association of depressive and anxiety symptoms with usual walking and obstacle avoidance in patients with Parkinson's disease. METHODS: Patients were divided into three groups: without depressive and anxiety symptoms (n = 28); depressive symptoms only (n = 15); and depressive and anxiety symptoms (n = 19). Symptoms of depression and anxiety were evaluated by the Hospital Anxiety and Depression scale. Participants walked across a pathway in two experimental conditions: usual walking and obstacle avoidance. Kinematic data were recorded using an optoelectronic three-dimensional system. RESULTS: During usual walking, the depressive and anxiety symptoms group presented shorter stride length and longer double support phase compared with the without depressive and anxiety symptoms group, and lower velocity than the without depressive and anxiety symptoms and depressive symptoms groups. During the approach phase of obstacle avoidance, the depressive and anxiety symptoms group decreased the stride length and velocity, whereas the without depressive and anxiety symptoms and depressive symptoms groups did not modulate these parameters. The depressive and anxiety symptoms group also showed shorter step length and velocity, longer step duration, and wider step width during obstacle crossing. Additionally, the depressive and anxiety symptoms group presented shorter foot-to-obstacle horizontal distances, and lower horizontal mean velocities during obstacle crossing. Partial correlation analyses showed that both depressive and anxiety symptoms were associated with spatiotemporal gait parameters. CONCLUSION: Combined symptoms of depression and anxiety are associated with walking impairments in patients with Parkinson's disease in both usual walking and obstacle avoidance. Geriatr Gerontol Int 2019; 19: 868-873.

Author Correction: Variability of crossing phase in older people with Parkinson's disease is dependent of obstacle height.

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has not been fixed in the paper.

Auditory Cueing for Gait Impairment in Persons With Parkinson Disease: A Pilot Study of Changes in Response With Disease Progression.

BACKGROUND AND PURPOSE: Gait impairments in persons with Parkinson disease (PD) are difficult to manage. Auditory cueing has been shown to be an effective therapy. However, the optimal time to introduce cues with respect to disease stage has not yet been established. This longitudinal study examines the effect of auditory cues on gait characteristics in people with early PD at 2 time points, 3 years apart. METHODS: We assessed 25 people with PD from the Incidence of Cognitive Impairment in Cohorts with Longitudinal Evaluation-Parkinson's disease (ICICLE-PD) study. Participants walked with and without an auditory cue set at individual cadence. Characteristics of step velocity, step length, step time, step length variability, and step time variability were collected using an instrumented walkway. In a subset of 9 participants with PD, all assessments were repeated 3 years later. Twenty-nine healthy older adults were assessed at 1 time point to provide comparison data. RESULTS: At baseline, independent of group, step velocity, step length, and step time improved with auditory cue; however, there was an increase in step time variability, indicating a worsening of gait with the cue. Three years later, in the smaller subset the response to cue was improved, demonstrated by increased step velocity and length but step time variability was no longer increased. DISCUSSION AND CONCLUSIONS: This pilot study indicates that people with early PD have small benefits from auditory cues and the benefit increases as disease progresses. Early in disease the benefit of cue may come at the cost of increased variability. Therefore, the time to introduce an auditory cue in PD rehabilitation may be important to optimize therapeutic effect.Video Abstract available for more insights from the authors (see Video, Supplemental Digital Content 1, available at: http://links.lww.com/JNPT/A243).

Variability of crossing phase in older people with Parkinson's disease is dependent of obstacle height.

Our aim was investigating variability in spatiotemporal parameters and kinetics of obstacle avoidance steps of different height obstacles in people with Parkinson's disease (PD) and healthy older people. Twenty-eight participants have included (15 PD - stage disease: 2.1 ± 0.4 pts) and 13 healthy older people (control group). Each subject performed 10 trials of the following tasks: low obstacle, intermediate obstacle and high obstacle. The presentation order was randomized by block for each condition and participant. The spatiotemporal parameters was collected by GAITRite. An optoelectronic system (Optotrak Northern Digital Inc.) with 100 Hz of frequency was used to collect obstacle parameters. The kinect parameters (propulsion impulse and braking impulse) were acquire through two force plates (AccuGait), with a frequency of acquisition 200 Hz. Intersteps variability was calculated throughout mean values, standard deviation and coefficient of variation of two obstacle avoidance steps for each trial. PD group presented greater variability than control group on vertical and horizontal distances to the obstacle. Obstacle height did not change kinect's parameters for both groups. The combination of task complexity (obstacle height) and disease impairments (gait alteration, loss of balance, etc) contributing for greater variability of Parkinson's group. Besides, low obstacle and high obstacle seem to exacerbate variability of distance between obstacle and foot.

Objective measures of unobstructed walking and obstacle avoidance in Parkinson's disease subtypes.

BACKGROUND: Objective measures of gait in Parkinson's disease (PD) patients according to motor subtypes are not yet fully understood. Although recent advances have been made for unobstructed walking, further work is required on locomotor tasks challenging postural stability, such as obstacle avoidance. RESEARCH QUESTION: This study aimed to investigate the influence of PD motor subtypes on objective measures of locomotion during unobstructed walking and obstacle avoidance. METHODS: Thirty-five PD patients classified as postural instability and gait disorder (PIGD) and 30 as tremor dominant (TD), as well as 45 healthy controls (CG) walked along an 8-m pathway under two conditions: (a) unobstructed walking and (b) obstacle avoidance. Outcome measures included spatiotemporal parameters recorded by an optoelectronic tridimensional system. RESULTS: During unobstructed walking, the PIGD group exhibited shorter stride length, slower velocity, and longer double support phase compared to the TD and CG groups. The TD group also presented slower stride velocity compared to the CG. The PIGD and TD groups presented shorter stride duration than the CG. Regarding obstacle avoidance, the PIGD group exhibited shorter distances for leading foot placement before obstacle, trailing foot placement after obstacle and trailing crossing step length compared to the TD and CG groups. The PIGD group exhibited wider leading crossing step width, lower trailing toe clearance, and slower leading and trailing velocity during obstacle avoidance compared to the CG. SIGNIFICANCE: PIGD subtype patients showed worse modifications in objective measures of unobstructed walking and obstacle avoidance. The observed modifications may contribute to increased fall occurrence in PIGD patients.

Continuous use of textured insole improve plantar sensation and stride length of people with Parkinson's disease: A pilot study.

Findings involving the acute benefits of textured insoles on gait in people with Parkinson's disease (PD) are still controversial. To our best acknowledge, the continuous use of textured insoles on gait in people with PD has not been investigated yet. The aim of this pilot study was to obtain preliminary data of the effects of textured insoles on gait and plantar sensation in people with PD after one-week intervention and one-week follow-up period. Nineteen patients with PD were distributed into two groups: experimental group and control group. Initially, the plantar sensation was assessed through Semmes-Weinstein Monofilaments. Then, participants performed 5 trials of walking (without insoles) at a self-selected speed. Gait data were collected using an optoelectronic system. Plantar sensation and gait assessments were repeated in three moments: before and after one-week wearing the group-specific insoles, and after one week wearing conventional insoles (follow-up). The textured insole had half-sphere elevations placed in the distal phalanx of the hallux, heads of metatarsophalangeal joints and heel. Results revealed that the use of textured insole for one week improved plantar sensation and stride length. However, only benefits on plantar sensation were maintained after the follow-up period. Our results suggest that the continuous use of textured insoles for one week benefits plantar sensation and gait in patients with PD. These results support the hypothesis that enhanced somatosensory feedback to the sensory system result in an improved motor output of gait.

Comparação do equilíbrio e da mobilidade funcional entre pacientes com doença de Parkinson ativos e inativos / Comparison of balance and functional mobility among active and inactive patients with Parkinson's disease

A doença de Parkinson compromete o equilíbrio e a mobilidade funcional. A atividade física tem um importante papel se contrapondo aos efeitos da doença, podendo promover benefícios na mobilidade de pacientes. O estudo teve como objetivo comparar o desempenho em equilíbrio e mobilidade funcional de pacientes com doença de Parkinson ativos e inativos. Participaram do estudo 41 pacientes distribuídos, em ativos (19) e inativos (22), de acordo com a pontuação obtida no questionário de Baecke modificados para idosos e confirmado pela quantidade de prática regular de atividade física. Todos os pacientes foram avaliados em relação ao equilíbrio através da escala de equilíbrio de Berg e em relação à mobilidade funcional através do Timed up and Go test. Não foram encontradas diferenças significativas em relação ao equilíbrio. Entretanto, pacientes ativos apresentaram melhores desempenhos (6,86 ± 1,16 s) na mobilidade funcional quando comparado com pacientes inativos (9,19 ± 4,40 s). Manter níveis ótimos de atividade física é um importante fator para a melhora da mobilidade de pacientes com doença de Parkinson, refletindo na realização das atividades diárias e na qualidade de vida.

Parkinson's disease affects the balance and mobility. Physical activity has an important role in minimizing the effects of the disease and may provide benefits in patient mobility. The study aimed to compare the balance and mobility performance of active and inactive patients with Parkinson's disease. The study included 41 patients distributed in active (19) and inactive (22) groups according to the score obtained in the Baecke questionnaire modified for the elderly and it was confirmed by amount of the practice of regular physical activity. All patients were assessed for the balance through the Berg balance scale and in relation to mobility through the Timed Up and Go test. There were no significant between group differences for balance. However, active patients were better (6.86 ± 1.16 s) in mobility when compared with inactive patients (9.19 ± 4.40 s). Maintaining optimal levels of physical activity is an important factor to improve the mobility performance of patients with Parkinson's disease, reflecting in daily activities and quality of life.

Synchrony of gaze and stepping patterns in people with Parkinson's disease.

The aim of the present study was to test the hypothesis that people with Parkinson's disease (PD) are more dependent than healthy individuals on visual information in an on-line manner to guarantee accurate foot placement into an intended stepping target. Patients with PD and age-matched healthy participants walked along a pathway and were required to step onto either one or two targets during the walk trial. Outcome measures included absolute error (accuracy) and error variability (precision) of foot placement onto the first target, and the time interval between the gaze transfer away from the first target and heel contact on the same target. When there was a single target in the travel path, both groups fixated the target until after heel contact on the target. However, when challenged with an additional target, both groups transferred their gaze from the first target prior to heel contact. Interestingly, only people with PD increased anterior-posterior absolute error (first target) when there was more than one target in the travel path. Premature gaze transfer was associated with decline in stepping accuracy (anterior-posterior absolute error) in people with PD. These findings suggest that both people with PD and healthy individuals prioritize the planning of future actions over the execution of ongoing steps, while walking. Additionally, current findings support the notion people with PD are more dependent on visual feedback to make on-line corrections and adjustments to their foot trajectory in order to guarantee accurate foot placement into an intended stepping target.

Effects of disease severity and medication state on postural control asymmetry during challenging postural tasks in individuals with Parkinson's disease.

The aim of this study was to investigate the effects of disease severity and medication state on postural control asymmetry during challenging tasks in individuals with Parkinson's disease (PD). Nineteen people with PD and 11 neurologically healthy individuals performed three standing task conditions: bipedal standing, tandem and unipedal adapted standing; the individuals with PD performed the tasks in ON and OFF medication state. The participants with PD were distributed into 2 groups according to disease severity: unilateral group (n=8) and bilateral group (n=11). The two PD groups performed the evaluations both under and without the medication. Two force plates were used to analyze the posture. The symmetric index was calculated for various of center of pressure. ANOVA one-way (groups) and two-way (PD groups×medication), with repeated measures for medication, were calculated. For main effects of group, the bilateral group was more asymmetric than CG. For main effects of medication, only unipedal adapted standing presented effects of PD medication. There was PD groups×medication interaction. Under the effects of medication, the unilateral group presented lower asymmetry of RMS in anterior-posterior direction and area than the bilateral group in unipedal adapted standing. In addition, the unilateral group presented lower asymmetry of mean velocity, RMS in anterior-posterior direction and area in unipedal standing and area in tandem adapted standing after a medication dose. Postural control asymmetry during challenging postural tasks was dependent on disease severity and medication state in people with PD. The bilateral group presented higher postural control asymmetry than the control and unilateral groups in challenging postural tasks. Finally, the medication dose was able to reduce postural control asymmetry in the unilateral group during challenging postural tasks.

The motor deficits caused by parkinson's disease are not able to block adjustments for a safe strategy during obstacle crossing in individuals with moderate disease / O déficit motor causado pela doença de parkinson não é capaz de bloquear os ajustes para uma estratégia segura durante a travessia de obstáculos em indivíduos com doença moderada / El déficit motor causados por la enfermedad de parkinson no es capaces de bloquear los ajustes para una estrategia de seguridad durante la travesía del obstáculo en individuos con enfermedad moderada

The aim of this study was to verify whether patients with Parkinson's disease (PD) are able to adjust their motor behavior according to restrictions imposed by the task instruction during walking with obstacle crossing. Eighteen elderly people (moderate motor compromise) with a diagnosis of PD walked on a pathway and cross an obstacle according to the following conditions: walking at preferred velocity; walking at maximum vertical elevation of the feet to cross the obstacle; walking at maximum step length to cross the obstacle; walking at maximum velocity. The modulations were directly related to the instructions provided to patients with PD before performing each task, which seems to indicate that attentional cues can influence and benefit strategies during obstacle crossing. In conclusion, patients with PD are able to adjust walking during obstacle crossing according to instructions given to them, which increases their safety.

O objetivo deste estudo foi verificar se pacientes com doença de Parkinson (DP) são capazes de modular o comportamento motor de acordo com restrições impostas pela instrução na tarefa de ultrapassagem de obstáculo. Dezoito idosos com diagnóstico de DP (comprometimento motor moderado) andaram sobre uma passarela e ultrapassaram um obstáculo de acordo com as seguintes instruções: velocidade preferida; elevação máxima do pé para ultrapassagem do obstáculo; máximo comprimento do passo de ultrapassagem; ultrapassagem em máxima velocidade. As modulações realizadas estão diretamente relacionadas às instruções dadas aos pacientes antes da realização de cada tarefa, o que indica que dicas auditivas podem influenciar e beneficiar as estratégias utilizadas. Através deste estudo é possível concluir que pacientes com DP são capazes de modular a ultrapassagem de obstáculo de acordo com a instrução que lhes é dada, o que aumenta a segurança na tarefa.

El objetivo de este estudio fue verificar se los pacientes con enfermedad de Parkinson (EP) son capaces de modular el comportamiento motor de acuerdo con restricciones impuestas por la instrucción en la tarea de sobrepasar un obstáculo. Dieciocho adultos mayores con diagnóstico de EP (con deficiencia motora moderada) caminaran sobre una pasarela e sobrepasaran un obstáculo de acuerdo con las siguientes instrucciones: velocidad preferida; elevación máxima del pie para sobrepasar el obstáculo, máxima distancia del paso para sobrepasar el obstáculo; sobre pasada máxima velocidad. Las modulaciones realizadas están directamente relacionadas a las instrucciones dadas a los pacientes antes de la realización de cada tarea, lo que indica que pautas auditivas pueden influenciar e beneficiar las estrategias utilizadas. A través de este estudio se puede concluir que pacientes con EP son capaces de modular la sobrepasada de obstáculo de acuerdo con la instrucción que les es dada, lo que aumenta la seguridad en la tarea.

Challenging Postural Tasks Increase Asymmetry in Patients with Parkinson's Disease.

The unilateral predominance of Parkinson's disease (PD) symptoms suggests that balance control could be asymmetrical during static tasks. Although studies have shown that balance control asymmetries exist in patients with PD, these analyses were performed using only simple bipedal standing tasks. Challenging postural tasks, such as unipedal or tandem standing, could exacerbate balance control asymmetries. To address this, we studied the impact of challenging standing tasks on postural control asymmetry in patients with PD. Twenty patients with PD and twenty neurologically healthy individuals (control group) participated in this study. Participants performed three 30s trials for each postural task: bipedal, tandem adapted and unipedal standing. The center of pressure parameter was calculated for both limbs in each of these conditions, and the asymmetry between limbs was assessed using the symmetric index. A significant effect of condition was observed, with unipedal standing and tandem standing showing greater asymmetry than bipedal standing for the mediolateral root mean square (RMS) and area of sway parameters, respectively. In addition, a group*condition interaction indicated that, only for patients with PD, the unipedal condition showed greater asymmetry in the mediolateral RMS and area of sway than the bipedal condition and the tandem condition showed greater asymmetry in the area of sway than the bipedal condition. Patients with PD exhibited greater asymmetry while performing tasks requiring postural control when compared to neurologically healthy individuals, especially for challenging tasks such as tandem and unipedal standing.

Different types of additional somatosensory information do not promote immediate benefits on gait in patients with Parkinson's disease and older adults / Diferentes tipos de informação somatossensorial adicional não promovem benefícios imediatos no andar de pacientes com doença de Parkinson e idosos sadios / Diferentes tipos de información somatosensorial adicional no promueven beneficios inmediatos sobre la marcha en pacientes con enfermedad de Parkinson y los mayores saludables

Plantar cutaneous stimulation has been shown to improve gait in Parkinson's disease (PD), but the effects of different types of insoles have not been tested. We evaluated the immediate effect of different types of insoles on gait in PD patients and healthy older adults. Nineteen PD patients and nineteen healthy older adults performed and performed a walking task at their self-selected speed in three conditions: conventional insole, insole with a raised ridge around the foot perimeter, and insole with half-spheres. Plantar sensation was evaluated before and after the walking protocol. There were no differences between groups for plantar sensation before and after the walking task. PD patients demonstrated reduced stride length and stride velocity. There were no immediate benefits offered by the insoles on gait of either group. The increased plantar cutaneous stimulation does not promote immediate benefits on gait in PD patients and healthy older adults.

A estimulação cutânea plantar beneficia o andar de pacientes com doença de Parkinson (DP), mas os efeitos de diferentes tipos de palmilhas ainda não foram testados. Nós avaliamos o efeito imediato de diferentes tipos de palmilhas no andar de pacientes com DP e idosos saudáveis. Dezenove pacientes com DP e dezenove idosos sadios andaram em três condições: palmilha convencional, palmilha com borda na parte externa da superfície do pé e palmilha com semi-esferas. A sensibilidade plantar foi avaliada antes e após o protocolo do andar. Não foram encontradas diferenças entre os grupos para sensibilidade plantar antes e após a tarefa do andar. Os pacientes apresentaram reduzida velocidade e menor comprimento da passada. Não foram verificados benefícios imediatos das palmilhas no andar para os grupos. O aumento na estimulação cutânea plantar não promoveu benefícios imediatos no andar de pacientes com DP e controles.

La estimulación plantar beneficia el andar e de pacientes con enfermedad de Parkinson-(EP), pero los efectos de diferentes tipos de plantillas no fueron testados. Evaluamos el efecto inmediato de diferentes tipos de plantillas en el andar de pacientes con EP y en mayores saludables. Diecinueve pacientes con EP y diecinueve controles fueron evaluados en el andar en tres condiciones: plantilla convencional, plantilla con borde en la superficie exterior del pie e plantilla con semi-esferas. La sensibilidad plantar fue evaluada antes y después de lo andar. No hubo diferencias entre los grupos para la sensibilidad plantar antes y después de lo andar. Los pacientes mostraron velocidad reducida y menor longitud de la zancada. No hubo beneficios inmediatos de las plantillas en el andar para los grupos. El aumento en la estimulación plantar no promovió beneficios inmediatos en el andar para los grupos.

Obstacle crossing with dual tasking is a danger for individuals with Alzheimer's disease and for healthy older people.

BACKGROUND/OBJECTIVE: The aim of this study was to analyze the effects of dual tasking on obstacle crossing during walking by individuals with Alzheimer's disease (AD) and by healthy older people. METHODS: Thirty four elderly individuals (16 healthy subjects and 18 individuals with AD) were recruited to participate in this study. Three AD individuals and one control participant were excluded due to exclusion criteria. The participants were instructed to walk barefoot at their own speed along an 8 m long pathway. Each participant performed five trials for each condition (unobstructed walking, unobstructed walking with dual tasking, and obstacle crossing during walking with dual tasking). The trials were completely randomized for each participant. The mid-pathway stride was measured in the unobstructed walking trials and the stride that occurred during the obstacle avoidance was measured in the trials that involved obstacle crossing. RESULTS/CONCLUSION: The behavior of the healthy elderly subjects and individuals with AD was similar for obstacle crossing during walking with dual tasking. Both groups used the "posture first" strategy to prioritize stability and showed decreased attention to executive tasking while walking. Additionally, AD had a strong influence on the modifications that are made by the elderly while walking under different walking conditions.

Disease severity affects obstacle crossing in people with Parkinson's disease.

The current study evaluated the effects of disease severity on the control of obstacle crossing in people with idiopathic Parkinson's disease (PD). Forty-five subjects participated in the study, including 15 patients with mild PD (classified as stage 1 to 1.5 of the Hoehn and Yahr Rating Scale), 15 patients with moderate PD (classified as stage 2 to 3 of the Hoehn and Yahr Rating Scale), and 15 neurologically healthy individuals. Groups were matched by sex, age, body mass, and body height. The obstacle crossing task required participants to walk along a pathway and step over an obstacle (half of the knee height, positioned in the middle of the pathway). Patients were tested in a typically medicated state. Kinematic data were recorded using an optoelectronic tridimensional system. The outcome measures included spatiotemporal measures of obstacle avoidance. There were no significant differences between patients with mild PD and healthy individuals. Patients with moderate PD exhibited shorter distances for leading toe clearance and leading foot placement after the obstacle than did healthy individuals. Patients with moderate PD tended to exhibit a lower leading horizontal mean velocity during obstacle crossing than did healthy individuals. We found significant negative relationships between obstacle crossing measures and disease severity (score on the motor section of the Unified Parkinson's Disease Rating Scale). These findings suggest that disease severity affects locomotor behavior during obstacle crossing in PD. Specifically, obstacle avoidance was not affected in the early stages of PD; however, bradykinesia and hypometria influenced obstacle crossing in patients with moderate PD.