Effects of 40 Hz Rhythmic Stimulation on Alzheimer’s Disease and Cognitive Function
10.16476/j.pibb.2024.0377
- VernacularTitle:40 Hz节律刺激对阿尔茨海默病和认知功能的影响
- Author:
Na ZHAO
1
;
Sheng HE
1
;
Li-Nan SHI
1
Author Information
1. State Key Laboratory of Brain and Cognitive Science, Institute of Biophysics, Chinese Academy of Sciences, Beijing 100101, China
- Publication Type:Journal Article
- Keywords:
Alzheimer’s disease;
40 Hz rhythmic stimulation;
non-invasive treatment;
neural entrainment;
neural mechanism;
cognitive function
- From:
Progress in Biochemistry and Biophysics
2024;51(10):2405-2417
- CountryChina
- Language:Chinese
-
Abstract:
Alzheimer’s disease (AD), characterized by cognitive decline and neurodegeneration, currently relies on pharmacological treatments that are limited in efficacy and often accompanied by side effects. As the number of AD patients increases, so does the economic burden on both the global healthcare system and families of patients, further worsening the quality of life for patients in their later years. Therefore, it is crucial to find new and more effective therapeutic approaches. This necessity has sparked a growing interest in non-invasive therapies, such as 40 Hz rhythmic stimulation, which aims to modulate brain activity to potentially reverse pathological changes and alleviate symptoms. This review provides an overview of the effects of 40 Hz stimulation on AD pathology and symptoms, its impact on cognitive functions in healthy individuals, the underlying mechanisms of action, and strategies to enhance the treatment’s compliance and effectiveness. Research has demonstrated that 40 Hz rhythmic stimulation, particularly through auditory and visual modalities, can influence core AD pathologies. In mouse models of AD, this stimulation has been shown to reduce amyloid-beta protein (Aβ) plaques and phosphorylated tau protein levels, hallmarks of AD pathology. These effects are thought to stem from enhanced waste clearance mechanisms, facilitated by the stimulation of the glymphatic system and the activation of microglia. Clinical applications in AD patients have shown promising results, with improvements noted in cognitive functions and behavioral symptoms. These findings suggest that 40 Hz rhythmic stimulation could offer a non-pharmacological option to mitigate the pathological progression and symptomatic expression of AD. In healthy individuals, the cognitive outcomes of 40 Hz stimulation appear more variable. Some studies indicate potential enhancements in memory and attention, proposing that 40 Hz stimulation may bolster cognitive resilience and processing efficiency in a non-diseased brain. However, these effects are not consistently replicated across studies, indicating that individual differences and specific stimulation parameters may significantly influence outcomes. The beneficial effects of 40 Hz rhythmic stimulation are believed to be primarily due to neural entrainment, where neural circuits synchronize their activity to the external frequency. This entrainment may restore the balance between excitatory and inhibitory neural activity, which is often disrupted in AD mice and AD patients. By reinforcing natural brain rhythms, 40 Hz stimulation may enhance neural connectivity and function, facilitating cognitive and memory processes that are deteriorated in AD. Neural entrainment at 40 Hz has been demonstrated to aid in restoring neural network function, enhancing the glymphatic system, improving cerebral blood flow, and providing neuroprotection. These mechanisms are thought to work synergistically to regulate brain activity, potentially leading to a reduction in lesions and an improvement in cognitive performance. To optimize the therapeutic benefits of 40 Hz stimulation, several factors need to be considered. Treatment protocols should be tailored to individual needs, accounting for variability in disease progression and personal health status. Enhancing patient compliance involves simplifying treatment regimens and using portable, user-friendly devices that can be easily incorporated into daily routines. Ongoing research should focus on refining stimulation parameters and delivery methods to maximize efficacy and minimize potential side effects. In conclusion, while 40 Hz rhythmic stimulation represents a promising avenue for treating AD and enhancing cognitive functions, further research is required to fully elucidate its mechanisms, refine its application, and ensure its practicality and efficacy in broad clinical and everyday settings.
