Beam walking is a highly studied assessment of walking balance. Recent research has demonstrated that brief intermittent visual rotations and occlusions can increase the efficacy of beam walking practice on subsequent beam walking without visual perturbations. We sought to examine the influence of full vision removal during practice walking on a treadmill-mounted balance beam. Although visual disruptions improved performance of this task, we hypothesized that removing visual feedback completely would lead to less balance improvements than with normal vision due to the specificity of practice. Twenty healthy young adults trained to walk at a fixed speed on a treadmill-mounted balance beam for 30min, either with, or without, normal vision. We compared their balance pre-, during, and posttraining by calculating their step-offs per minute and the percentage change in step-offs per minute. Balance improved in both groups after training, with no significant difference in percentage change in step-offs between the normal vision and the no vision participants. On average, the no vision participants had twice as many step-offs per minute as the normal vision group during training. Although previous experiments show that intermittent visual perturbations led to large enhancements of the effectiveness of beam walking training, completely removing visual feedback did not alter training effectiveness compared with normal vision training. It is likely a result of sensory reweighting in the absence of vision, where a greater weight was placed on proprioceptive, cutaneous, and vestibular inputs.
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