Review on the application of virtual reality to vestibular rehabilitation

[ES] Introducción y objetivo: Las nuevas tecnologías nos conceden nuevas fórmulas para analizar y modificar la relación del sujeto con el medio. La realidad virtual sería su máxima expresión. Explicaremos los fundamentos básicos que se aplican en estas tecnologías, las cuales poseen muchos elementos en común con la organización de nuestro sentido del equilibrio. Método: Revisión narrativa. Resultados: Expondremos las características técnicas y los mecanismos de compensación aplicados en los dispositivos de rehabilitación vestibular. Discusión: Revisaremos algunos estudios que analizan las ventajas e inconvenientes de la realidad virtual frente a la terapia física convencional. Conclusiones: Los sistemas de seguimiento ocular, postural o de giro cefálico aplicados a la realidad virtual, pueden emplearse en el desarrollo de dispositivos diagnósticos o de rehabilitación vestibular. Se necesitas más estudios que comparen su eficacia respecto a la terapia física tradicional

Rest intervals during virtual reality gaming augments standing postural sway disturbance

Immersive virtual reality (VR) can cause acute sickness, visual disturbance, and balance impairment. Some manufacturers recommend intermittent breaks to overcome these issues; however, limited evidence examining whether this is beneficial exists. The aim of this study was to examine whether taking breaks during VR gaming reduced its effect on postural sway during standing balance assessments. Twenty-five people participated in this crossover design study, performing 50 min of VR gaming either continuously or with intermittent 10 min exposure/rest intervals. Standing eyes open, two-legged balance assessments were performed immediately pre-, immediately post- and 40 min post-exposure. The primary outcome measure was total path length; secondary measures included independent axis path velocity, amplitude, standard deviation, discrete and continuous wavelet transform-derived variables, and detrended fluctuation analysis. Total path length was significantly (p < 0.05) reduced immediately post-VR gaming exposure in the intermittent rest break group both in comparison to within-condition baseline values and between-condition timepoint results. Conversely, it remained consistent across timepoints in the continuous exposure group. These changes consisted of a more clustered movement speed pattern about a lower central frequency, evidenced by signal frequency content. These findings indicate that caution is required before recommending rest breaks during VR exposure until we know more about how balance and falls risk are affected.Ross Allan Clark, Ancret Szpak, Stefan Carlo Michalski, and Tobias Loetsche

Modelo cinemático ajustado como fator preditivo da força excêntrica relativa durante o exercício nórdico

This study aimed to assess the combination of video-based kinematic variables adjusted by intrinsic covariates to predict the relative eccentric force (RelF) during the Nordic curl. The participants (n = 21) performed Nordic curls (3 trials; 3-min rest) on a device measuring the eccentric force. The peaks were normalized by body weight. Kinovea software was used to track angular and linear velocity and acceleration from recorded videos. Two prediction models with multiple linear regression equations associated kinematic, anthropometric, and age variables to adjust the actual RelF. The equations obtained the predicted RelF. The actual RelF was inversely correlated with height (r = −.52), tangential (r = −.50) and centripetal accelerations (r = −.715), and angular velocity (r = −.70). The best prediction models combined angular velocity with age (F2,18 = 15.1, P = .001, r = .792, r 2 = .627) and with height (F2,18 = 14.5, P = .001, r = .785, r 2 = .616). No differences were observed between actual and predicted values (P = .993−.994), with good levels of agreement and consistency (intraclass correlation coefficient = .77−.78; Cronbach α = .86−.87). Bland–Altman results showed high levels of agreement and low biases. The standard error of measurement and minimal detectable change ranges were 0.46 to 0.49 N/kg and 1.28 to 1.36 N/kg, respectively. Also, the percentage of standard error of measurement was below 10% (7.92%– 8.35%). The coefficient of variation analysis returned a 14.54% and 15.13% for each model, respectively. Kinematic analysis offers portability and low cost to current expensive or technical impaired dynamometry-based techniques to assess the RelF.Este estudo teve como objetivo avaliar a combinação de variáveis cinemáticas baseadas em vídeo-análise ajustadas por covariáveis intrínsecas ao participante para prever a força excêntrica relativa durante o exercício nórdico. Os participantes (n = 21) realizaram o exercício nórdico (3 tentativas; 3 minutos de intervalo) em um dispositivo que avalia a força excêntrica. Os picos de força foram normalizados pela massa corporal. O software Kinovea foi usado para rastrear velocidade angular e linear e aceleração de vídeos gravados. Dois modelos de predição com equações de regressão linear múltipla associaram variáveis cinemáticas, antropométricas e de idade para ajustar a força excêntrica relativa real. As equações obtiveram um predito da força excêntrica relativa. A força excêntrica relativa real foi inversamente correlacionada com a altura (r = −0,52), aceleração tangencial (r = −0,50) e centrípeta (r = −0,715) e velocidade angular (r = −0,70). Os melhores modelos de previsão combinaram a velocidade angular com a idade (F2,18 = 15,1; p = 0,001; r =0,792; r 2 = 0,627) e com altura (F2,18 = 14,5; p = 0,001; r =0,785; r 2 = 0,616). Não foram observadas diferenças entre os valores reais e previstos (p = 0,993−0,994), com bons níveis de concordância e consistência (coeficiente de correlação intraclasse =0,77−0,78; Cronbach α = 0,86−0,87). Os resultados de Bland-Altman mostraram altos níveis de concordância e baixos vieses. O erro padrão de medição e as variações mínimas detectáveis foram de 0,46 a 0,49 N/kg e de 1,28 a 1,36 N/kg, respectivamente. Além disso, a porcentagem do erro padrão de medição ficou abaixo de 10% (7,92%–8,35%). A análise do coeficiente de variação retornou 14,54% e 15,13% para cada modelo, respectivamente. A análise cinemática oferece portabilidade e baixo custo às atuais técnicas baseadas em dinamometria para avaliar a força excêntrica relativa

The Impact of Multisensory and Cognitive Load on Younger and Older Adults’ Cognitive-Motor Dual-Task Performance

Maintaining postural control efficiently is dependent upon the coordination of motor, sensory and cognitive systems, all of which are subject to decline with aging. Evidence suggests that increased cognitive load, sensory loss and cognitive impairments alone reduce postural control, but rarely are these factors considered in conjunction. We therefore investigated how younger and older adults’ postural control was impacted by increased cognitive load, simulated vision impairment, and hearing loss. Using a Nintendo Wii Balance Board, 32 younger (M = 23.03 SD = 3.53), and 27 older adults, 16 with hearing loss, (M = 77.13 SD = 7.53) and 11 without hearing loss (M = 71.27 SD = 11.30), underwent five balance conditions (i.e., eyes closed, normal and low vision single- and dual-tasks). We found that as task complexity increased (i.e., presence of a visual and/or backwards counting task), postural control decreased. Younger adults outperformed older adults on all tests of postural control, whereas minimal variations in postural performance existed between older adults with and without hearing loss. Older adults with hearing loss had greater medial-lateral sway in single-task normal and low vision conditions. Positive dual-task postural costs were evident among all three groups, but no group differences existed. Under normal and low vision conditions, older adults without hearing loss displayed positive dual-task cognitive costs, while those with hearing loss experienced no costs, suggesting differences in task prioritization. Taken together, our results illustrate that aging impacts how increased cognitive load and the presence of vision impairment challenge can affect postural control