Biofeedback for training balance and mobility tasks in older populations: a systematic review

<p>Abstract</p> <p>Context</p> <p>An effective application of biofeedback for interventions in older adults with balance and mobility disorders may be compromised due to co-morbidity.</p> <p>Objective</p> <p>To evaluate the feasibility and the effectiveness of biofeedback-based training of balance and/or mobility in older adults.</p> <p>Data Sources</p> <p>PubMed (1950-2009), EMBASE (1988-2009), Web of Science (1945-2009), the Cochrane Controlled Trials Register (1960-2009), CINAHL (1982-2009) and PsycINFO (1840-2009). The search strategy was composed of terms referring to biofeedback, balance or mobility, and older adults. Additional studies were identified by scanning reference lists.</p> <p>Study Selection</p> <p>For evaluating effectiveness, 2 reviewers independently screened papers and included controlled studies in older adults (i.e. mean age equal to or greater than 60 years) if they applied biofeedback during repeated practice sessions, and if they used at least one objective outcome measure of a balance or mobility task.</p> <p>Data Extraction</p> <p>Rating of study quality, with use of the Physiotherapy Evidence Database rating scale (PEDro scale), was performed independently by the 2 reviewers. Indications for (non)effectiveness were identified if 2 or more similar studies reported a (non)significant effect for the same type of outcome. Effect sizes were calculated.</p> <p>Results and Conclusions</p> <p>Although most available studies did not systematically evaluate feasibility aspects, reports of high participation rates, low drop-out rates, absence of adverse events and positive training experiences suggest that biofeedback methods can be applied in older adults. Effectiveness was evaluated based on 21 studies, mostly of moderate quality. An indication for effectiveness of visual feedback-based training of balance in (frail) older adults was identified for postural sway, weight-shifting and reaction time in standing, and for the Berg Balance Scale. Indications for added effectiveness of applying biofeedback during training of balance, gait, or sit-to-stand transfers in older patients post-stroke were identified for training-specific aspects. The same applies for auditory feedback-based training of gait in older patients with lower-limb surgery.</p> <p>Implications</p> <p>Further appropriate studies are needed in different populations of older adults to be able to make definitive statements regarding the (long-term) added effectiveness, particularly on measures of functioning.</p

Ageing vision and falls: a review

Background: Falls are the leading cause of accidental injury and death among older adults. One of three adults over the age of 65 years falls annually. As the size of elderly population increases, falls become a major concern for public health and there is a pressing need to understand the causes of falls thoroughly. Main body of the abstract: While it is well documented that visual functions such as visual acuity, contrast sensitivity, and stereo acuity are correlated with fall risks, little attention has been paid to the relationship between falls and the ability of the visual system to perceive motion in the environment. The omission of visual motion perception in the literature is a critical gap because it is an essential function in maintaining balance. In the present article, we first review existing studies regarding visual risk factors for falls and the effect of ageing vision on falls. We then present a group of phenomena such as vection and sensory reweighting that provide information on how visual motion signals are used to maintain balance. Conclusion: We suggest that the current list of visual risk factors for falls should be elaborated by taking into account the relationship between visual motion perception and balance control

Standing balance: Age-related differences in postural responses to continuous perturbations

This series of studies used an oscillating platform paradigm to investigate the effects of aging on anticipatory and reactive mechanisms of postural control. We hypothesized that young adults would use anticipatory mechanisms in response to predictable postural perturbations and that aging would be characterized by a decrease in anticipatory postural muscle activity resulting in less effective balance control. Young and old healthy adults were asked to maintain standing balance on a force platform that oscillated continuously 20 cm peak-to-peak in the anterior/posterior (A/P) direction at successively increasing frequencies of 0.1, 0.25, 0.5 to 0.61 Hz. Subjects completed trials of externally- and self-triggered perturbations. The effect of mechanical stimulation of the foot plantar surface boundaries on postural responses of older adults was tested. Postural responses to perturbations were characterized using centre of pressure (COP), centre of mass (COM), muscle activity (EMG) and number of steps. A mathematical model representing the body motion in response to continuous sinusoidal platform perturbations was implemented. Young adults used anticipatory adjustments regardless of the degree of predictability of postural challenges in externally- and self-triggered perturbations. Old adults responded to a predictable externally-triggered postural challenge using reactive postural adjustments independent of the frequency of platform oscillation, the direction of perturbation and without adapting over multiple trials. Old adults used anticipatory adjustments only in self-triggered perturbations or when additional sensory stimulation from foot plantar surface boundaries was available. The present series of experiments demonstrated for the first time that cutaneous stimulation of the foot plantar surface boundaries increases stability and facilitates the use of anticipatory control strategies. These results support the importance of cutaneous mechanoreceptors at the boundaries of the foot plantar surface for the control of postural reactions evoked by continuous perturbations. The results from these experiments clearly show that the ability to compensate for an impending and highly predictable perturbation decreases with aging. The age-related difference in the control of standing balance on a continuous oscillating platform recorded in experimental data was partially explained through increased levels of sensory noise and neural delays in the simulated data of old adults. Our results support the concept of a dynamic stability, according to which, in addition to the horizontal location of the COM with respect to the base of support, the magnitude and direction of its corresponding velocity provide critical information pertaining to one\u27s ability to control balance. Based on model work, we demonstrated that the acceleration parameters of a perturbation must be taken into account when calculating stability limits. We derived for the first time the equations for calculating these stability limits related to continuous translations of the base of support

Musa someşană : poesii poporale române din jurul Năseudului. Partea 1: Balade

Musa someşană : poesii poporale române din jurul Năseudului. Partea 1: Balade. - Gherla : Proprietatea, editura şi tiparul Tipografiei "Aurora" A. Todoran, 1892. - 96 p

Aging and selective sensorimotor strategies in the regulation of upright balance

Background. The maintenance of upright equilibrium is essentially a sensorimotor integration task. The central nervous system (CNS) has to generate appropriate and complex motor responses based on the selective and rapid integration of sensory information from multiple sources. Since each sensory system has its own coordinate framework, specific time delay and reliability, sensory conflicts may arise and represent situations in which the CNS has to recalibrate the weight attributed to each particular sensory input. The resolution of sensory conflicts may represent a particular challenge for older adults given the age-related decline in the integrity of many postural regulating systems, including musculoskeletal and sensory systems, as well as neural processing and conduction of information. The effects of aging and adaptation (by repeated exposures) on the capability of the CNS to select pertinent sensory information and resolve sensory conflicts were thus investigated with virtual reality (VR) in the present study. Methods. Healthy young and older adults maintained quiet stance while immersed in a virtual environment (VE) for 1 hour during which transient visual and/or surface perturbations were randomly presented. Visual perturbations were induced by sudden pitch or roll plane tilts of the VE viewed through a helmet-mounted display, and combined with or without surface perturbations presented in a direction that was either identical or opposite to the visual perturbations. Results. Results showed a profound influence of aging on postural adjustments measured by electromyographic (EMG) responses and displacements of the center of pressure (COP) and body\u27s center of mass (COM) in the recovery of upright stance, especially in the presence of sensory conflicts. Older adults relied more on vision as compared to young adults. Aging affects the interaction of the somatosensory and visual systems on the control of equilibrium during standing and the ability of CNS to resolve sensory conflicts. However, even with a one-hour immersion in VE and exposure to sensory conflicts, it is possible for the CNS to recalibrate and adapt to the changes, while improving balance capability in older adults. Conclusion. Preventive and rehabilitation programs targeting postural control in older adults should take into account the possible impairment of sensory organization or sensorimotor integration and include VE training under conditions of sensory conflicts. © 2007 Bugnariu and Fung; licensee BioMed Central Ltd