Falls and fall-related injuries is a huge problem among older adults, with one in three adults over the age of 65 suffering a fall annually with 20-30% of falls resulting in serious injury. Fall prevention has been a primary focus of aging research over the past three decades;however, most programs aimed at addressing physiological factors have only achieved only modest effects on fall rates. Hence with the aging population, there remains a critical need to develop novel approaches that significantly reduce an individual's inherent risk of falling. This study will investigate the ability of a promising ne neuro-rehabilitation approach, Cranial Nerve Non-Invasive Neuromodulation (CN-NINM), induced via tongue stimulation, to improve gait and standing balance in older adults at risk for falls while also providing insight into the mechanisms underlying these functional gains. To accomplish this, sixteen older adults with a history of one to three falls in the previous six months will undergo two weeks of gait and balance exercises. The subjects will be randomized into two groups, with eight subjects receiving active CN-NINM stimulation during the exercises, and eight subjects receiving placebo CN-NINM stimulation while doing the same exercises.
The first aim will test the hypothesis that subjects receiving active CN-NINM stimulation will show significantly greater gains on both the dynamic gait index (DGI) and the sensory organization test (SOT)than subjects receiving placebo stimulation. This would be a highly important finding clinically, since poor performance on both the DGI and SOT are linked with fall risk.
The second aim will investigate the sensorimotor mechanisms underlying the effect of CN-NINM enhanced exercise on clinical metrics of gait and balance. The premise of CN-NINM training is that it enhances neuroplasticity and learning, resulting in improved integration and neural processing of the sensory information that underlying the control of balance and locomotion. Subjects will undergo quantitative motion and electromyographic analysis in the presence of sensory, cognitive and physical perturbations introduced during walking. The gait evaluations will be used to test the hypothesis that subjects receiving active CN-NINM stimulation will exhibit better lateral balance and less antagonist muscle co-activation during walking, reflecting better disturbance rejection and improved sensorimotor control of gait. Successful completion of these aims will lead to a larger longitudinal study to investigate the efficacy of CN-NINM rehabilitation to prevent falls in older adults. This approach would represent an inexpensive intervention that could positively impact mobility and quality of life of millions of older adults.
The goal of this project is to improve standing and walking balance in older adults who have a history of falling. We will use a type of electrical stimulation via the tongue to improve the way the brain learns during rehabilitation exercises. If successful, we will conduct a larger study focused on the reduction of falls, along with the high associated costs (financial, personal, and health), in older adults.
| Franz, Jason R; Francis, Carrie; Allen, Matt et al. (2017) Visuomotor Entrainment and the Frequency-Dependent Response of Walking Balance to Perturbations. IEEE Trans Neural Syst Rehabil Eng 25:1132-1142 |
| Francis, Carrie A; Franz, Jason R; O'Connor, Shawn M et al. (2015) Gait variability in healthy old adults is more affected by a visual perturbation than by a cognitive or narrow step placement demand. Gait Posture 42:380-5 |
| Franz, Jason R; Francis, Carrie A; Allen, Matthew S et al. (2015) Advanced age brings a greater reliance on visual feedback to maintain balance during walking. Hum Mov Sci 40:381-92 |
| Lenhart, Rachel L; Francis, Carrie A; Lenz, Amy L et al. (2014) Empirical evaluation of gastrocnemius and soleus function during walking. J Biomech 47:2969-74 |
