From pathogenesis to non-medical therapy: A review of exploring sensory and multi-sensory stimulation as a non-invasive treatment approach for Alzheimer’s disease

Alzheimer’s disease (AD) is a progressive neurodegenerative disorder, marked by the accumulation of amyloid-beta plaques, tau pathology, and synaptic dysfunction, ultimately leading to memory loss, cognitive decline, neuropsychiatric symptoms and neuronal degeneration that impairs daily functioning. Despite the availability of pharmacological treatments developed to slow down symptom progression, their clinical efficacy remains uncertain, and they are frequently associated with adverse side effects, underscoring the urgent demand for safer and more effective therapeutic alternatives. Non-pharmacological approaches, therefore, have been investigated and are considered promising alternative therapeutic strategies for AD. This paper outlines the pathological features and neural network changes that occur across the progression of Alzheimer’s disease (AD), reviews the effects of different sensory stimulation approaches on reducing these AD-associated changes, and discusses the potential mechanisms underlying various sensory and multisensory stimulation interventions in mitigating AD-related symptoms. These sensory stimulation interventions, including 40 Hz Gamma Entrainment Using Sensory Stimulation [GENUS], Photobiomodulation, Bright Light Therapy, Music Therapy, Aromatherapy, Tactile Stimulation, and Multisensory Stimulation, are found to slow down the progression of AD by ameliorating multiple AD pathologies, enhancing cognitive function, promoting neuroplasticity, regulating sleep patterns, and reducing behavioural or neuropsychiatric symptoms. Crucially, this present work integrates both human and animal studies, aligning clinical outcomes with mechanistic insights derived from animal studies, thereby bridging preclinical and clinical research to promote the translation of sensory interventions into effective treatments for patients with AD.