Cognitive and Motor Cortical Activity During Cognitively Demanding Stepping Tasks in Older People at Low and High Risk of Falling

Background: Choice stepping reaction time tasks are underpinned by neuropsychological, sensorimotor, and balance systems and therefore offer good indices of fall risk and physical and cognitive frailty. However, little is known of the neural mechanisms for impaired stepping and associated fall risk in older people. We investigated cognitive and motor cortical activity during cognitively demanding stepping reaction time tasks using functional near-infrared spectroscopy (fNIRS) in older people at low and high fall risk. Methods: Ninety-five older adults [mean (SD) 71.4 (4.9) years, 23 men] were categorized as low or high fall risk [based on 12-month fall history (≥2 falls) and/or Physiological Profile Assessment fall risk score ≥1]. Participants performed a choice stepping reaction time test and a more cognitively demanding Stroop stepping task on a computerized step mat. Cortical activity in cognitive [dorsolateral prefrontal cortex (DLPFC)] and motor (supplementary motor area and premotor cortex) regions was recorded using fNIRS. Stepping performance and cortical activity were contrasted between the groups and between the choice and Stroop stepping conditions. Results: Compared with the low fall risk group (n = 71), the high fall risk group (n = 24) exhibited significantly greater DLPFC activity and increased intra-individual variability in stepping response time during the Stroop stepping task. The high fall risk group DLPFC activity was greater during the performance of Stroop stepping task in comparison with choice stepping reaction time. Regardless of group, the Stroop stepping task elicited increased cortical activity in the supplementary motor area and premotor cortex together with increased mean and intra-individual variability of stepping response times. Conclusions: Older people at high fall risk exhibited increased DLPFC activity and stepping response time variability when completing a cognitively demanding stepping test compared with those at low fall risk and to a simpler choice-stepping reaction time test. This increased hemodynamic response might comprise a compensatory process for postural control deficits and/or reflect a degree of DLPFC neural inefficiency in people with increased fall risk

Prefrontal and Motor Planning Cortical Activity during Stepping Tasks Is Related to Task Complexity but Not Concern about Falling in Older People: A fNIRS Study

This study investigated the effect of concern about falling on neural efficiency during stepping in older people. Community-dwellers aged >65 years were categorised as having low (n = 71) and high (n = 28) concerns about falling based on the Iconographical Falls Efficacy Scale (IconFES 10-item, scores <19 and ≥19, respectively). Participants performed a choice stepping reaction time test (CSRT), an inhibitory CSRT (iCSRT), and a Stroop stepping test (SST)) on a computerised step mat. Cortical activity was recorded using functional near-infrared spectroscopy. There were no significant differences in stepping response times or cortical activity in the dorsolateral prefrontal cortex (DLPFC), supplementary motor area (SMA), and premotor cortex (PMC) between those with and without concern about falling. However, stepping response times and cortical activity in the PFC, SMA, and PMC were significantly higher in the SST compared with the CSRT in the whole sample. PMC activity was also higher in the SST compared to the iCSRT. These findings demonstrate that cortical activity is higher in cognitively demanding stepping tasks that require selective attention and inhibition in healthy older people. The lack of association between concern about falling and neural efficiency during stepping in this older sample may reflect their only moderate scores on the IconFES

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 60 min 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

Um programa de atividade física generalizada leva a manutenção funcional em indivíduos com doença de Parkinson

A Doença de Parkinson (DP) é uma doença crônico-neurodegenerativa, caracterizada principalmente por: tremor de repouso, rigidez, bradicinesia, alterações da marcha e instabilidade postural. Com isso, há uma diminuição na qualidade de vida e na independência dos idosos com DP, com redução na habilidade de desempenhar atividades da vida diária. Assim, diversas propostas têm sido feitas no intuito de auxiliar o tratamento medicamentoso, como a pratica de atividade física. Entretanto, a maior parte dessas propostas envolve programas de pequena duração ou que foquem em pontos específicos da doença. Dessa forma, o principal objetivo do presente estudo foi avaliar o efeito de um treinamento multimodal de 8 meses sobre o equilíbrio dinâmico e a mobilidade funcional de pacientes com Doença de Parkinson idiopática, por meio da Escala de Equilíbrio Funcional de Berg (EEFB) e do teste Timed “Up and Go” (TUG). Participaram do estudo 8 voluntários nos estágios de leve à moderado da doença (Estágios de Hoehn e Yahr = 1 a 3), cognitivamente preservados, avaliados em sob efeito da medicação, antes e após a realização do protocolo de exercícios proposto. Também foram avaliados após 3 meses do término do treinamento, com intuito de avaliar o efeito do destreino nesses indivíduos e não foram encontradas alterações na EEFB e TUG. Dessa forma, podemos afirmar que mesmo com o avanço da DP, esse programa de treinamento foi eficaz na manutenção do equilíbrio dinâmico e na mobilidade funcional desses sujeitos por meio da atividade física

O lado de início da doença influencia a destreza manual de pacientes com doença de Parkinson

A doença de Parkinson (DP) é caracterizada pelo início assimétrico de sintomas motores e compromete a destreza manual. Espera-se que pacientes com o lado de início da doença preferido comprometido consigam manter bom desempenho com o lado mais afetado (LMA) no teste de destreza manual decorrente da experiência motora ao longo da vida. O objetivo do estudo foi verificar a interferência da coincidência entre o lado de início da doença e preferência manual no desempenho da destreza manual, LMA e lado menos afetado, em pacientes com DP. Os pacientes foram distribuídos conforme o lado de início: Grupo Coincidente (lado preferido acometido) e Grupo Não Coincidente (lado não preferido acometido). A destreza manual foi avaliada pelo teste Annett Pegboard adaptado. A análise estatística ANOVA de dois fatores (grupo x lado), medidas repetidas no último fator, revelou que o Grupo Não Coincidente dispendeu maior tempo para completar o teste com o LMA (p=0,001), enquanto, o Grupo Coincidente dispendeu o mesmo tempo com ambos os lados, indicando que pacientes nos estágios iniciais e com início da doença pelo lado preferido perdem a proficiência manual. Sugere-se que intervenções para melhorar as habilidades manuais sejam aplicadas desde o diagnóstico da doença, principalmente em pacientes com o lado preferido acometido.Parkinson’s disease (PD) is characterized by the asymmetric onset of motor symptoms and manual dexterity. It is expected that patients with preferred onset side affected can maintain a good performance with the more affected side (MAS) due to the life-long motor experience. The aim of the study was to verify the interference of coincidence between the disease onset side and manual preference in the performance of manual dexterity, MAS and less affected side in patients with PD. The patients were distributed according to the disease onset side: Coincident group (preferred affected side) and non-coincident group (non-preferred affected side). Manual dexterity was assessed by the Annett Pegboard adapted test. The statistical analysis ANOVA for two factors (group x side), with repeated measures in the last factor, revealed that the Non-coincident group spent more time to complete the test with the MAS (p=0.001), while the Coincident group spent the same time to perform the test with both sides, indicating that patients in the early stages of PD and disease onset by preferred side lose the manual proficiency. Therefore, interventions to improve manual skills have become important since the diagnosis of the disease, especially in patients with the preferred affected side

Impacto da doença de Parkinson sobre as características cinéticas e cinemáticas da tarefa de levantar e andar, em caidores e não caidores

Background: Recent studies have shown that Parkinson's disease (PD) patients have some difficult to perform sequential tasks, as the sit-to-walk (STW) task. The difficult to perform this task may be attributed to the PD physical impairments, neurophysiologic and clinic impairments, the context that the task is performed and to the conservative pattern adopted for these patients. PD patients show some impairment in the motor circuitry, sensory processing and program of action. The STW task, like another sequential task requires continuous program end execution in healthy subjects. Therefore, we expect that PD patients perform this task with appropriate motor solutions, as for example, separate the STW in two distinct tasks to ensure the stability and demonstrate less risk of fall. Thus two hypotheses were developed: PD patients separate the STW in two distinct task and show some alterations in kinetic and kinematic parameters when compared with healthy matched-control; PD patients fallers show a more conservative behavior than non- fallers. Aim: To assess healthy elderlies, PD patients non-fallers and fallers motor behavior's in the STW in time constraints, in two different studies. Methods: 28 subjects participated in the study 1 and two different groups were established: GDP group, with 14 PD patients and GC group, with healthy matched-control. In the study 2, 26 subjects participated and two different groups were established: GNC group, with 13 PD patients non-fallers and GCA group, with 13 PD patients fallers (they have been considered fallers whether had fallen at least once in the last year). To perform the STW, the participants were seated in a chair armless and backless, barefoot on the two force plates. The height of chair was standardized in 0.42 m. After the subjects hear a mobile ring, they should rise from the chair and answer it. With their hands on their knees, the subjects rose from a chair immediately after the mobile...Introdução: Recentes estudos têm demonstrado a dificuldade de pacientes com doença de Parkinson (DP) em realizar tarefas sequenciais, como o caso da tarefa de levantar e andar (LEA). A dificuldade em realizar tarefas dessa natureza pode ser atribuída às restrições físicas dessa população, aos aspectos neurofisiológicos e clínicos da DP, ao contexto em que a tarefa é realizada e também à escolha de um padrão precavido adotado por esses pacientes. Os pacientes com DP apresentam comprometimentos na circuitaria motora, no processamento sensorial e na programação da ação. A LEA, como outra tarefa motora sequencial, exige programação e execução contínua em indivíduos neurologicamente saudáveis, portanto, espera-se que pacientes com DP apresentem soluções adequadas ao seu contexto, como por exemplo, separar a tarefa em duas distintas a fim de garantir a estabilidade e apresentar menor risco de cair, principalmente quando realizada sob restrição temporal. Dessa forma duas hipóteses foram elaboradas para este estudo: pacientes com DP separam a tarefa de LEA com demanda temporal em duas distintas e apresentam modificações nos parâmetros cinéticos e cinemáticos durante a LEA com demanda temporal em comparação com seus pares neurologicamente saudáveis; pacientes com DP caidores apresentam um comportamento ainda mais precavido quando comparados a seus pares não caidores. Objetivo: Avaliar o comportamento motor de indivíduos idosos saudáveis e idosos com DP caidores e não caidores na tarefa de LEA com demanda temporal, em dois diferentes estudos. Método: No estudo 1, participaram 28 indivíduos, formando intencionalmente dois grupos: grupo GDP, com 14 pacientes com DP idiopática e o grupo GC com 14 indivíduos neurologicamente sadios (grupo controle). No estudo 2, participaram 26 indivíduos, formando intencionalmente dois grupos: grupo GNC, com 13 pacientes com DP idiopática não caidores e o grupo GCA, com 13...Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

Investigating balance disorders and fall risk in people with Parkinson’s disease

Postural instability and gait disorders (PIGD) increase the risk of falling in people with Parkinson’s disease (PD). In addition, lack of optimal levodopa response, executive dysfunction and increased reliance on cognitive resources may also contribute to fall risk in this population. In a series of related projects, I investigated people with PD categorised into different subtypes, including the presense/absense of PIGD symptoms, as well as investigated how levodopa response and executive dysfunction increase fall risk in people with PD. In addition, I assessed neural correlates of postural instability and gait disorders using functional near-infrared spectroscopy (fNIRS). I conducted five studies that: (i) contrasted fall rates and circumstances as well as a range of disease-related, clinical and functional measures between people with different PD subtypes; (ii) compared gait stability before and after levodopa intake between people with different PD subtypes and between individuals who took different daily doses of levodopa; (iii) identified sensorimotor, balance and cardiovascular factors that discriminated between those with normal/impaired executive function in people with PD, and determined whether executive dysfunction is a significant risk for falls in PD; and (iv & v) I compared activation patterns in cognitive and motor cortical regions using fNIRS between people with PD and healthy controls during: (iv) simple and complex stepping tasks during simple walking and; (v) gait adaptability tasks. The main findings were that (i) the PIGD subtype were more likely to suffer falls due to freezing of gait, balance-related falls and falls at home; (ii) the PIGD subtype exhibited impaired gait stability which was worsened by levodopa intake; (iii) mild and marked executive dysfunction were identified as independent risk factors for falls; (iv) people with PD appear unable to utilize their cognitive and motor cortical resources when completing stepping tasks requiring inhibition; and (v) during gait adaptability tasks, people with PD adopted a more conservative gait pattern to successfully negotiate obstacles and stepping targets despite exhibiting increased cognitive cortical activity. My findings elucidate several aspects of fall risk in people with PD, which may facilitate both the development of fall risk assessments and fall prevention strategies for this population

Parkinson's disease severity and motor subtype influence physical capacity components

The severity of Parkinson's disease (PD) and PD's motor subtypes influence the components of physical capacity. The aim of this study was to investigate the impact of both PD severity and motor subtype in the performance of these components. Thirty-six PD patients were assigned into four groups: Tremor (TD) initial and TD mild, akinetic-rigid (AR) initial, and AR mild. Patients' strength, balance, coordination, mobility and aerobic capacity were evaluated and groups were compared using a two-way ANOVA (severity and subtype as factors). AR presents a poorer performance than TD in almost all tests. Also this performance was worsened with the advance of the disease in AR, contrary to TD. We conclude that AR and TD subgroups are different about their performance on physical capacity components, moreover, this performance worsens with the advance of the disease of the AR group, but not for TD.A doença de Parkinson (DP) é caracterizada por diferentes subtipos motores e supõe-se que o desempenho dos componentes da capacidade física é influenciado por esses subtipos. O objetivo desse estudo foi investigar o impacto que a severidade e o subtipo da DP podem trazer sobre o desempenho dos componentes da capacidade física. Trinta e seis pacientes com DP foram distribuídos em quarto grupos: com dominância de tremor (TD) inicial e TD intermediário ou acinesia (AR) inicial e AR intermediário. A força, equilíbrio, coordenação, mobilidade e capacidade aeróbia foram avaliados. AR apresentou um pior desempenho que TD em nos testes. Esse desempenho foi pior com o aumento da severidade da doença em AR, mas não em TD. Conclui-se que os grupos AR e TD são diferentes em relação ao desempenho dos componentes da capacidade física, mas principalmente, esse desempenho piora com o avanço da doença em AR, mas não em TD

Análise cinética e cinemática do levantar e andar em jovens e idosos

ResumoA tarefa de levantar e andar (LEA) é muito usada no dia a dia e há a necessidade de conhecer o comportamento de idosos nesse tipo de ação. Diante disso, o objetivo foi avaliar jovens (GJ) e idosos (GI) na tarefa de LEA. Foram realizadas avaliações cinéticas e cinemáticas e do desempenho da tarefa entre os grupos. Após a análise estatística, foi observada apenas diferença estatística para a variável de máxima força vertical durante a fase perda de contato com o assento ao término do levantar, assim como o tempo de desempenho dessa fase foi menor para o GJ. O envelhecimento causa um impacto significativo na força e contribui, assim, para um maior dispêndio de tempo ao levantar da cadeira. Com isso, maior atenção deve ser dada à fase de transição da LEA