The use of functional near infrared spectroscopy and gait analysis to characterize cognitive and motor processing in early-stage patients with multiple sclerosis.

Background: Dual-task paradigms are a known tool to evaluate possible impairments in the motor and cognitive function in patients with multiple sclerosis (MS). A technique to evaluate the cortical function during movement is functional near-infrared spectroscopy (fNIRS). The evaluation of the MS course or its treatment by associating fNIRS with gait measurements may be flexible and low-cost; however, there are no feasibility studies in the literature using these combined techniques in early-stage patients with MS. Objective: To evaluate cortical hemodynamics using fNIRS and gait parameters in patients at early stages of MS and in healthy controls during a dual-task paradigm. Methods: Participants performed cognitive tasks while walking to simulate daily activities. Cortical activation maps and gait variability were used to evaluate differences between 19 healthy controls and 20 patients with MS. Results and conclusion: The results suggest an enhanced cortical activation in the motor planning areas already at the early stages of MS when compared to controls. We have also shown that a systematic analysis of the spatiotemporal gait variability parameters indicates differences in the patient population. The association of cortical and gait parameters may reveal possible compensatory mechanisms related to gait during dual tasking at the early stages of the disease.

The immediate effect of different loads does not alter muscle co-activation of the upper limb in young adults with dyskinetic cerebral palsy.

BACKGROUND: There is insufficient information on muscle co-activation in the upper limbs to help healthcare providers develop treatment programs for patients with dyskinetic cerebral palsy (DCP). RESEARCH QUESTION: Is the degree of muscle co-activation greater in adults with DCP than in healthy individuals? Does the use of different arm weights modify co-contraction in individuals with PCD? METHODS: Fourteen healthy individuals (control group [CG]) and 14 individuals with DCP (dyskinetic group [DG]) participated in the study. The degree of muscle co-activation of the dominant limb during drinking from a mug was compared between the two groups. The task was divided into a going, adjusting, and returning phase. In the DG, an analysis was also performed on using an arm weight during the functional task. The loads corresponded to 10, 20, and 30 % of maximum isometric muscle strength measured in each participant. RESULTS: In comparing the two groups, the DG exhibited a greater muscle co-activation in the shoulder and elbow muscles during the going phase, the shoulder, elbow, and wrist during the adjusting phase; and the elbow during the returning phase. The DG also showed a greater mean index of curvature (MIC), time to perform the movement phases, and lesser mean velocity (Vm) to drinking. In analyzing the DG's arm weight, no effect on co-activation, MIC, time to perform the movement phases, and Vm to drinking were found with the loads tested (p > 0.05). CONCLUSION: Muscle co-activation is increased in adults with DCP in comparison to healthy individuals. Moreover, arm weight during the functional activity of drinking from a mug did not alter co-activation, although an immediate effect was expected.

Contralesional Cathodal Transcranial Direct Current Stimulation Does Not Enhance Upper Limb Function in Subacute Stroke: A Pilot Randomized Clinical Trial.

Transcranial direct current stimulation (tDCS) has the potential to improve upper limb motor outcomes after stroke. According to the assumption of interhemispheric inhibition, excessive inhibition from the motor cortex of the unaffected hemisphere to the motor cortex of the affected hemisphere may worsen upper limb motor recovery after stroke. We evaluated the effects of active cathodal tDCS of the primary motor cortex of the unaffected hemisphere (ctDCSM1UH) compared to sham, in subjects within 72 hours to 6 weeks post ischemic stroke. Cathodal tDCS was intended to inhibit the motor cortex of the unaffected hemisphere and hence decrease the inhibition from the unaffected to the affected hemisphere and enhance motor recovery. We hypothesized that motor recovery would be greater in the active than in the sham group. In addition, greater motor recovery in the active group might be associated with bigger improvements in measures in activity and participation in the active than in the sham group. We also explored, for the first time, changes in cognition and sleep after ctDCSM1UH. Thirty subjects were randomized to six sessions of either active or sham ctDCSM1UH as add-on interventions to rehabilitation. The NIH Stroke Scale (NIHSS), Fugl-Meyer Assessment of Motor Recovery after Stroke (FMA), Barthel Index (BI), Stroke Impact Scale (SIS), and Montreal Cognitive Assessment (MoCA) were assessed before, after treatment, and three months later. In the intent-to-treat (ITT) analysis, there were significant GROUP∗TIME interactions reflecting stronger gains in the sham group for scores in NIHSS, FMA, BI, MoCA, and four SIS domains. At three months post intervention, the sham group improved significantly compared to posttreatment in FMA, NIHSS, BI, and three SIS domains while no significant changes occurred in the active group. Also at three months, NIHSS improved significantly in the sham group and worsened significantly in the active group. FMA scores at baseline were higher in the active than in the sham group. After adjustment of analysis according to baseline scores, the between-group differences in FMA changes were no longer statistically significant. Finally, none of the between-group differences in changes in outcomes after treatment were considered clinically relevant. In conclusion, active CtDCSM1UH did not have beneficial effects, compared to sham. These results were consistent with other studies that applied comparable tDCS intensities/current densities or treated subjects with severe upper limb motor impairments during the first weeks post stroke. Dose-finding studies early after stroke are necessary before planning larger clinical trials.

Adult dyskinetic cerebral palsy: Upper limb movement and muscle function.

AIM: The aim of this study was to characterize upper limb motor function during a comparative analysis of electromyographic and upper limb movement analysis during drinking between healthy adults and individuals with DCP. METHOD: Fifteen healthy individuals (CG) and fifteen individuals with DCP (DG) participated in the study. Upper limb function was analyzed during drinking and consisted of a task divided into three phases: the going, the adjustment, and the return. RESULTS: Electromyographic analysis revealed a lower activity of the anterior deltoid, posterior deltoid, and biceps brachii muscles in the DG. When comparing the interactions between groups and phases, only biceps brachii shower lower muscle activity during going and adjustment phases. The DG presented a smaller range of motion (ROM) for the shoulder, elbow, forearm and wrist movements. An interaction between groups and phases showed smaller ROM for the flexion and internal rotation of the shoulder, elbow flexion, forearm pronation, and ulnar deviation in the return phase compared to CG. INTERPRETATION: The results may contribute positively to the quantification of the level of motor impairment and may be used as a reference for the development of therapeutic interventions for patients with DCP.

Cognition and brain function in elderly Tai Chi practitioners: A case-control study.

OBJECTIVE: To compare cognition and brain function in elderly Tai Chi and Water Aerobics practitioners. METHODS: Eight Tai Chi (TC) and 8 Water Aerobics (WA) practitioners matched by gender, education and age underwent neuropsychological and fMRI scan during attention (Stroop Word Color Task) and working memory (N Back) tasks. RESULTS: Groups were similar for demographic and cognitive variables. Besides anxiety (smaller in TC group), there were no differences between groups in neuropsychological variables. During the Stroop Word Color Task, TC group had smaller brain activation in the right intracalcarine cortex, lateral occipital cortex, and occipital pole, than WA. During N back, TC group presented smaller brain activation in the right frontal pole and superior frontal gyrus. CONCLUSION: Despite the small number of participants in this preliminary study, both groups had similar cognitive performance, however the Tai Chi group required less brain activation to perform the attention and memory tasks, therefore they may have a more efficient cognitive performance than Water Aerobics group.

The use of the Gait Deviation Index for the evaluation Post-stroke Hemiparetic Subjects / O uso do índice de desvio de marcha para a avaliação de pacientes hemiparéticos após acidente vascular cerebral

BACKGROUND: The Gait Deviation Index, initially conceived to evaluate the gait of children with cerebral palsy, has been used as a quantitative parameter of gait pattern changes of individuals with other conditions. However, there are no studies evaluating changes in the gait pattern of chronic hemiparetic post-stroke subjects based on this index. AIMS: To characterize the changes in gait pattern according to the Gait Deviation Index and gait spatiotemporal parameters of chronic hemiparetic subjects compared to healthy subjects. METHODS: Retrospective study. Data were obtained from the database of the Gait Laboratory of Hospital Israelita Albert Einstein. Thirty subjects were included in this study, with previous unilateral, ischemic or hemorrhagic chronic stroke (time post-lesion > 6 months) and ability of walking classified as 2, 3, 4 or 5 according to Functional Ambulation Category. Data from 87 healthy subjects were included in control group, obtained from a normality database. Statistical analysis was applied through the Kruskall Wallis test, followed by Mann-Whitney post-hoc test, considering a critical p value <0.05. RESULTS: The Gait Deviation Index scores were decreased for both paretic (64.69 ± 16.29) and non-paretic limbs (64.88 ± 15.00) compared to control (101.01 ± 10.12; p < 0.001). No differences were observed in Gait Deviation Index scores between paretic and non-paretic limbs (p > 0.99). CONCLUSION: The findings of the current study demonstrate that the Gait Deviation Index may be a sensitive parameter to identify changes in the gait pattern of chronic hemiparetic post-stroke subjects.

BASES: O Índice de Desvio da Marcha, inicialmente utilizado para avaliar a marcha de crianças com paralisia cerebral, tem sido utilizado como parâmetro quantitativo de alterações de marcha de indivíduos com outras condições. No entanto, não existem estudos que avaliem alterações no padrão de marcha de indivíduos hemiparéticos crônicos pós-AVC com base nesse índice. OBJETIVOS: Caracterizar as alterações no padrão de marcha de acordo com o Índice de Desvio da Marcha e parâmetros espácio-temporais da marcha de sujeitos hemiparéticos crônicos em relação a indivíduos saudáveis. MÉTODOS: Estudo retrospetivos. Os dados foram obtidos a partir da base de dados do Laboratório de Marcha do Hospital Israelita Albert Einstein. Trinta indivíduos foram incluídos neste estudo, com AVC unilateral, isquêmico ou hemorrágico, crônico (tempo pós-lesão> 6 meses) e habilidade de caminhada classificada como 2, 3, 4 ou 5 segundo a Categoria de Ambulação Funcional. Os dados de 87 indivíduos saudáveis foram incluídos no grupo controle, obtido a partir da base de dados de normalidade. A análise estatística foi aplicada através do teste de Kruskall Wallis, seguido do teste pós-hoc de Mann-Whitney, considerando um valor p crítico <0,05. RESULTADOS: Os valores observados para o Índice de Desvio da Marcha foram menores para os membros paréticos (64,69 ± 16,29) e não-paréticos (64,88 ± 15) em relação ao controle (101,01 ± 10,12; p <0,001). Não foram observadas diferenças nos escores do Índice de Desvio da Marcha entre os membros paréticos e não paréticos (p> 0,99). CONCLUSÃO: Os achados do presente estudo demonstram que o Índice de Desvio da Marcha pode ser um parâmetro sensível para identificar alterações no padrão de marcha de indivíduos hemiparéticos crônicos pós-AVC.

Gait profile score and movement analysis profile in patients with Parkinson's disease during concurrent cognitive load

Background: Gait disorders are common in individuals with Parkinson's Disease (PD) and the concurrent performance of motor and cognitive tasks can have marked effects on gait. The Gait Profile Score (GPS) and the Movement Analysis Profile (MAP) were developed in order to summarize the data of kinematics and facilitate understanding of the results of gait analysis. Objective: To investigate the effectiveness of the GPS and MAP in the quantification of changes in gait during a concurrent cognitive load while walking in adults with and without PD. Method: Fourteen patients with idiopathic PD and nine healthy subjects participated in the study. All subjects performed single and dual walking tasks. The GPS/MAP was computed from three-dimensional gait analysis data. Results: Differences were found between tasks for GPS (P<0.05) and Gait Variable Score (GVS) (pelvic rotation, knee flexion-extension and ankle dorsiflexion-plantarflexion) (P<0.05) in the PD group. An interaction between task and group was observed for GPS (P<0.01) for the right side (Cohen's ¯d=0.99), left side (Cohen's ¯d=0.91), and overall (Cohen's ¯d=0.88). No interaction was observed only for hip internal-external rotation and foot internal-external progression GVS variables in the PD group. Conclusions: The results showed gait impairment during the dual task and suggest that GPS/MAP may be used to evaluate the effects of concurrent cognitive load while walking in patients with PD. .

Gait profile score and movement analysis profile in patients with Parkinson's disease during concurrent cognitive load.

BACKGROUND: Gait disorders are common in individuals with Parkinson's Disease (PD) and the concurrent performance of motor and cognitive tasks can have marked effects on gait. The Gait Profile Score (GPS) and the Movement Analysis Profile (MAP) were developed in order to summarize the data of kinematics and facilitate understanding of the results of gait analysis. OBJECTIVE: To investigate the effectiveness of the GPS and MAP in the quantification of changes in gait during a concurrent cognitive load while walking in adults with and without PD. METHOD: Fourteen patients with idiopathic PD and nine healthy subjects participated in the study. All subjects performed single and dual walking tasks. The GPS/MAP was computed from three-dimensional gait analysis data. RESULTS: Differences were found between tasks for GPS (P<0.05) and Gait Variable Score (GVS) (pelvic rotation, knee flexion-extension and ankle dorsiflexion-plantarflexion) (P<0.05) in the PD group. An interaction between task and group was observed for GPS (P<0.01) for the right side (Cohen's ¯d=0.99), left side (Cohen's ¯d=0.91), and overall (Cohen's ¯d=0.88). No interaction was observed only for hip internal-external rotation and foot internal-external progression GVS variables in the PD group. CONCLUSIONS: The results showed gait impairment during the dual task and suggest that GPS/MAP may be used to evaluate the effects of concurrent cognitive load while walking in patients with PD.