40 Hz sensory stimulation in Alzheimer's-model mice (Iaccarino 2016)
In 5XFAD mice, 40 Hz stimulation reduced amyloid-β, shifted microglia toward a clearance state and improved memory in mouse tasks. These are preclinical findings in mice.
The question: Does driving 40 Hz gamma activity with light or sound reduce Alzheimer's-type pathology in mice?
| Type of study | Preclinical study |
|---|---|
| Who took part | 5XFAD mice |
| What was done | 40 Hz gamma activity was driven optogenetically, then with non-invasive 40 Hz light flicker (2016), then with 40 Hz sound and combined audio-visual stimulation (2019). |
| How much weight it carries | Mixed evidence |
What it found
- In 5XFAD mice, driving 40 Hz gamma reduced amyloid-β and shifted microglia toward a clearance phenotype.
- Memory improved in mouse tasks.
- A 2019 study (Adaikkan) extended neuroprotection to tau models.
Limits
- These are preclinical results in mouse models.
- Whether 40 Hz entrainment measured at the scalp reaches deep memory structures in humans is an open question.
Where this sits
More in the library on light, flicker and 40 hz. For the wider picture, read 40 Hz, gamma and the brain.
This is our plain-language reading of the paper. It is not medical advice, and one study rarely settles a question.
Sources
- Iaccarino, H. F., Singer, A. C., Martorell, A. J., et al. (2016). Gamma frequency entrainment attenuates amyloid load and modifies microglia. Nature, 540(7632), 230–235. (Author Correction 2024, Nature 636:E2.) ; Martorell, A. J., et al. (2019). Multi-sensory Gamma Stimulation Ameliorates Alzheimer's-Associated Pathology and Improves Cognition. Cell, 177(2), 256–271. ; Adaikkan, C., et al. (2019). Gamma Entrainment Binds Higher-Order Brain Regions and Offers Neuroprotection. Neuron, 102(5), 929–943. doi.org/10.1038/nature20587