Maintaining balance during movement or standing requires continuous sensory adjustments to the surrounding environment. People with vestibular hypofunction significantly depend on visual cues and may struggle with balance in visually complex settings. However, vestibular, vision, and somatosensory systems are traditionally considered key to postural control and developing research studies. This suggests that auditory cues also play a crucial role, particularly for those with balance impairments.
The “auditory anchor” theory suggests that sudden changes in sound sources such as abrupt shifts from one side to another can disrupt spatial hearing and lead to instability and increased postural sway. This underscores the need for further research on how auditory information supports postural control in everyday scenarios. This study is published in PLOS One on January 24, 2025, and investigates the effects of broadband noise and real-world sounds on postural stability in individuals with vestibular hypofunction compared to healthy controls.
In this open-label clinical study (NCT04479761) individuals with unilateral peripheral vestibular hypofunction (vestibular group) were recruited between September 15, 2012, and December 23, 2023, from New York Eye and Ear Infirmary of Mount Sinai (vestibular rehabilitation center). Healthy subjects (control group) were recruited from the hospital community and universities. Individuals with unstable peripheral lesions such as Meniere’s disease, perilymphatic fistula, superior canal dehiscence, and acoustic neuroma were excluded. Several outcomes such as center of pressure (COP) root mean square of variability (VRMS) in the anterior-posterior (AP) and mediolateral (ML) directions and head VRMS in the AP, ML, pitch, yaw, and roll were measured.
A total of 28 participants (mean age = 61.5 years, 13% male, 15% female, mean dizziness handicap inventory [DHI] score = 35.6) were included in the vestibular loss group while 40 subjects (mean age = 52 years, 21% male, 20% female) were included in the control group. After adjusting for age, vestibular group was significantly higher sway compared to control group on COP ML in real sound static visual (P = 0.04, model estimated difference [MED] = 0.22) and no sounds dynamic visual (0.04, MED = 0.25); on COP AP dynamic visuals with white noise (P = 0.03, MED = 0.48) and real sound (P = 0.02, MED = 0.53); on head ML in static visual with no sound (P = 0.008, MED = 0.16), white noise (P = 0.034, MED = 0.13), real sound (P = 0.005, MED = 0.19), and dynamic visual with no sound (P = 0.018, MED = 0.17), white noise (P = 0.006, MED = 0.2), real sound (P = 0.006, MED = 0.22); on head AP in static visual with no sound (P = 0.01, MED = 0.21), white noise (P = 0.004, MED = 0.27), real sound (P = 0.004, MED = 0.28), and dynamic visual with no sound (P = 0.023, MED = 0.22), white noise (P < 0.001, MED = 0.41), real sound (P < 0.001, MED = 0.41); on pitch dynamic visuals with white noise (P = 0.04, MED = 0.006) and real sound (P = 0.015, MED = 0.007); on yaw dynamic visuals with real sounds (P = 0.036, MED = 0.004). However, there was no statistically significant difference observed between groups on a roll but the main effect of visual was found for both groups only on dynamic sounds with a P value of 0.04, with no interactions.
This study’s limitations include its cross-sectional design, laboratory setting, and use of headphones instead of loudspeakers to measure the effect of sound on balance, and the vestibular group was older with adjusting for age hidden the difference between groups in the ML.
In conclusion, auditory stimuli, particularly contextually relevant sounds significantly influenced postural stability in individuals with vestibular hypofunction during balance tasks but did not affect the control group. These findings underscore the potential role of auditory cues in developing balance interventions for vestibular disorders.
Reference: Lubetzky AV, Cosetti M, Harel D, et al. Real sounds influence postural stability in people with vestibular loss but not in healthy controls. PLoS One. 2025;20(1):e0317955. doi:10.1371/journal.pone.0317955
