Zaleski-King, Ashley

Purpose: Chronic dizziness and imbalance is often difficult to rehabilitate based on the complex set of systems involved. Recently, transcutaneous vagus nerve stimulation (tVNS) has been investigated as a noninvasive means to reduce symptoms associated with vestibular impairment, chronic dizziness, and neurological conditions affecting balance control. The purpose of this integrative review is to examine available data describing therapeutic efficacy and proposed mechanisms of tVNS in adult patients with dizziness and imbalance. Method: PubMed, Europe PMC, and Google Scholar searches were conducted using the following search terms from 1987 to 2024: “vagal nerve stimulat*” OR “vagus nerve stimulat*” OR “transcutaneous vagus nerve stimulat*” OR “tVNS” AND “dizziness,” “vertigo.” Articles were imported for screening and review through Rayyan. Articles discussing the use of tVNS to study metrics related to vestibular and balance function in adult humans were selected for full-text review. Results: Eleven articles were identified as meeting the inclusion criteria and are classified according to the neurotological class studied and level of evidence provided. Available data show that tVNS may benefit patients with dizziness and imbalance based on subjective metrics including quality of life and reduction in dizziness handicap. Less-controlled case study evidence suggests that additional benefit from tVNS may manifest in changes to vestibulo-ocular reflex function. Conclusion: Although tVNS exposure has provided variable degrees of benefit in both subjective (e.g., quality of life) and objective (e.g., changes in vestibulo-ocular reflex function and gait) contexts, the degree to which distinct mechanisms can explain these benefits is unclear.