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Denise C Gravelle

Publications and source records attributed to Denise C Gravelle.

3 recordsLinked to original sources

Noise-enhanced balance control in patients with diabetes and patients with stroke.

OBJECTIVE: Somatosensory function declines with diabetic neuropathy and often with stroke, resulting in diminished motor performance. Recently, it has been shown that input noise can enhance human sensorimotor function. The goal of this study was to investigate whether subsensory mechanical noise applied to the soles of the feet via vibrating insoles can be used to improve quiet-standing balance control in 15 patients with diabetic neuropathy and 15 patients with stroke. Sway data of 12 healthy elderly subjects from a previous study on vibrating insoles were added for comparison. METHODS: Five traditional sway parameters and three sway parameters from random-walk analysis were computed for each trial (no noise or noise). RESULTS: Application of noise resulted in a statistically significant reduction in each of the eight sway parameters in the subjects with diabetic neuropathy, the subjects with stroke, and the elderly subjects. We also found that higher levels of baseline postural sway in sensory-impaired individuals was correlated with greater improvements in balance control with input noise. INTERPRETATION: This work indicates that noise-based devices could ameliorate diabetic and stroke impairments in balance control.

Adult↗

Noise-enhanced balance control in older adults.

Somatosensory information is critical to balance control and fall prevention in older adults. Recently, it has been shown that low-level input noise (electrical or mechanical) can enhance the sensitivity of the human somatosensory system. In this study, we tested the effect of low-level electrical noise, applied at the knee, on balance control in 13 healthy elderly volunteers. Subjects performed multiple single-legged stance trials with imperceptible electrical noise applied at the knee during half of the trials. Balance performance was characterized using a force platform to measure the displacement of the center of pressure (COP) under the subject's stance foot. Seven sway parameters were extracted from the COP time series. Improved balance was defined as a reduction in postural sway as indicated by decreases in the COP measures. Six of the seven sway parameters decreased with electrical noise. Three of these parameters decreased significantly ( < 0.05), and a fourth parameter was borderline significant. Averaged across subjects, the application of electrical noise resulted in a 3.8% reduction in mediolateral COP standard deviation ( = 0.04), a 5.4% decrease in the maximum anteroposterior COP excursion ( = 0.03), a 3.1% reduction in the COP path length ( = 0.04), and a 7.8% decrease in swept area ( = 0.05). The results suggest that imperceptible electrical noise, when applied to the knee, can enhance the balance performance of healthy older adults. These findings suggest that electrical noise-based devices may be effective in improving balance control in elderly people.

Aged↗