BACKGROUND:
Dementia remains a major global health challenge characterized by progressive neurodegeneration, cognitive impairment, and psychosocial decline. Traditional pharmacological and non-pharmacological treatments yield limited improvements. The vagus nerve’s extensive projections offer a pathway to enhance neuroplasticity, regulate mood, and restore cognitive and emotional control disrupted in dementia. Vagal nerve stimulation (VNS), encompassing both invasive and non-invasive modalities such as transcutaneous auricular VNS (taVNS), has emerged as a promising adjunctive intervention for dementia-related cognitive decline and psychosocial dysfunction.
METHODS:
Systematic review: PubMed/MEDLINE, Cochrane Library, Web of Science, Embase,PsycINFO and Scopus. Search terms: “vagus nerve stimulation” OR “VNS” OR “vagal stimulation” OR “transcutaneous vagus nerve stimulation” OR “taVNS” OR “cervical VNS” OR “auricular VNS” OR “cranial nerve stimulation” AND “dementia” OR “Alzheimer’s disease” OR “cognitive impairment” OR “memory loss” OR “MCI” AND “psychosocial” OR “quality of life” OR “carer support” OR “social engagement” OR “therapy” OR “behavioral symptoms” OR “depression” OR “anxiety”.
RESULTS:
Evidence consistently supports VNS’s capacity to enhance cognitive functions and neural connectivity within memory networks such as the hippocampal-temporal-parietal circuits. Mechanistically, VNS activates the locus coeruleus-noradrenergic system, improving attention and memory while modulating neuroinflammation and tau pathology. Studies further reveal psychosocial benefits, with VNS promoting emotional regulation, reducing anxiety symptoms, and enhancing social interaction, effects that are particularly relevant within the neurovisceral integration and social health models of dementia care. From a biopsychosocial standpoint, the integration of VNS with interventions like cognitive stimulation and reminiscence therapy presents new opportunities for holistic dementia management. By linking autonomic regulation to social behavior, VNS may strengthen interpersonal engagement and caregivers’ relational experiences, supporting both patient wellbeing and care outcomes.Studies largely based in high-income settings, examined the influence of invasive and non-invasive VNS protocols on cognition, memory, emotional regulation, and social engagement among populations with Alzheimer’s disease, vascular dementia, and mild cognitive impairment.
CONCLUSION:
Clinical evidence suggests VNS may not only mitigates neurodegenerative processes but also fosters emotional and social resilience. Future research should focus on optimizing stimulation protocols, assessing long-term psychosocial outcomes, and embedding VNS within integrative dementia care frameworks aimed at maximizing both cognitive and relational quality of life.