Related Experiment Video
Updated: May 10, 2026
A Human-machine-interface Integrating Low-cost Sensors with a Neuromuscular Electrical Stimulation System for Post-stroke Balance Rehabilitation
Published on: April 12, 2016
Customized noise-stimulation intensity for bipedal stability and unipedal balance deficits associated with functional
Scott E Ross1, Shelley W Linens, Cynthia J Wright
1Department of Kinesiology, University of North Carolina-Greensboro, Greensboro, NC 27412, USA. seross@uncg.edu
Context:
Stochastic resonance stimulation (SRS) administered at an optimal intensity could maximize the effects of treatment on balance.
Objective:
To determine if a customized optimal SRS intensity is better than a traditional SRS protocol (applying the same percentage sensory threshold intensity for all participants) for improving double- and single-legged balance in participants with or without functional ankle instability (FAI).
Design:
Case-control study with an embedded crossover design.
Setting:
Laboratory.
Patients Or Other Participants:
Twelve healthy participants (6 men, 6 women; age = 22 ± 2 years, height = 170 ± 7 cm, mass = 64 ± 10 kg) and 12 participants (6 men, 6 women; age = 23 ± 3 years, height = 174 ± 8 cm, mass = 69 ± 10 kg) with FAI.
Intervention(S):
The SRS optimal intensity level was determined by finding the intensity from 4 experimental intensities at the percentage sensory threshold (25% [SRS₂₅], 50% [SRS₅₀], 75% [SRS₇₅], 90% [SRS₉₀]) that produced the greatest improvement in resultant center-of-pressure velocity (R-COPV) over a control condition (SRS₀) during double-legged balance. We examined double- and single-legged balance tests, comparing optimal SRS (SRS(opt1)) and SRS₀ using a battery of center-of-pressure measures in the frontal and sagittal planes.
Main Outcome Measure(S):
Anterior-posterior (A-P) and medial-lateral (M-L) center-of-pressure velocity (COPV) and center-of-pressure excursion (COPE), R-COPV, and 95th percentile center-of-pressure area ellipse (COPA-95).
Results:
Data were organized into bins that represented optimal (SRS(opt1)), second (SRS(opt2)), third (SRS(opt3)), and fourth (SRS(opt4)) improvement over SRS₀. The SRS(opt1) enhanced R-COPV (P ≤ .05) over SRS₀ and other SRS conditions (SRS₀ = 0.94 ± 0.32 cm/s, SRS(opt1) = 0.80 ± 0.19 cm/s, SRS(opt2) = 0.88 ± 0.24 cm/s, SRS(opt3) = 0.94 ± 0.25 cm/s, SRS(opt4) = 1.00 ± 0.28 cm/s). However, SRS did not improve R-COPV over SRS₀ when data were categorized by sensory threshold. Furthermore, SRS(opt1) improved double-legged balance over SRS₀ from 11% to 25% in all participants for the center-of-pressure frontal- and sagittal-plane assessments (P ≤ .05). The SRS(opt1) also improved single-legged balance over SRS₀ from 10% to 17% in participants with FAI for the center-of-pressure frontal- and sagittal-plane assessments (P ≤ .05). The SRS(opt1) did not improve single-legged balance in participants with stable ankles.
Conclusions:
The SRS(opt1) improved double-legged balance and transfers to enhancing single-legged balance deficits associated with FAI.
