Dr. Jackie Kilraine, DC, BCN — The Brain Fitness Doc

40 Hz Gamma Light and Sound

A Neighbor-Friendly Explanation

Thank you for requesting more information after watching the 40Hz gamma video. Here is the research behind what you saw, and where to learn more about the device I personally use.

Our brains naturally make gamma waves, especially when we are paying attention, learning, or remembering.

Light and sound pulsing 40 times per second can encourage the brain to follow that same 40-hertz rhythm. Human brain recordings show that this rhythm can reach areas involved in attention, memory, and higher-level thinking (Nature Communications).

What Researchers Are Studying

The brain's cleanup cells: In animal studies, 40-hertz stimulation activated microglia, the brain's cleanup cells, helping them surround and remove more beta-amyloid (Nature).

The brain's drainage system: It also activated the glymphatic system, which works like a waste-removal and drainage system for the brain (Nature).

Blood flow and brain connections: Researchers have observed better blood-vessel movement, stronger communication between brain regions, healthier synapses, and protection of myelin, the insulation around our nerve fibers (Nature Communications).

Movement of beta-amyloid: In aged monkeys, one hour of 40-hertz sound each day for seven days roughly doubled the amount of beta-amyloid measured in the cerebrospinal fluid. Researchers interpreted this as a possible sign that beta-amyloid was moving out of brain tissue and into the fluid for removal (PNAS).

Early human findings: Preliminary human studies have reported possible benefits involving sleep patterns, daily functioning, and preservation of brain structure. These findings require confirmation in larger studies (OVERTURE trial).

The Important Takeaway

Forty-hertz stimulation may help the brain enter a coordinated rhythm, activate cleanup systems, and improve communication between important brain areas. The animal research is compelling, but larger human studies are needed to determine how much of that benefit carries over to people.

This research does not prove that 40-hertz stimulation removes beta-amyloid, prevents Alzheimer's disease, or treats any medical condition in humans.

The 40 Hz Device I Use

Learn more about the 40-hertz light-and-sound device I use in my own practice and personally recommend.

Educational and Safety Disclaimer

This material is provided for educational and informational purposes only. It is not medical advice and is not intended to diagnose, treat, cure, or prevent Alzheimer's disease or any other disease or medical condition. The research described here, while compelling, does not prove that 40-hertz light-and-sound stimulation provides these benefits in humans.

Flickering-light stimulation should not be used by anyone with a history of seizures, epilepsy, photosensitivity, or migraines unless a qualified healthcare professional has specifically determined that it is appropriate. Consult a qualified healthcare professional before using light-or-sound stimulation if you have a neurological, psychiatric, hearing, vision, or other medical condition. Stop using the device and seek medical guidance if it causes headache, dizziness, nausea, visual discomfort, unusual sensations, or any other concerning symptoms.

Never use the device while driving, operating machinery, or doing anything that requires your full visual attention.

With you every step of the way,
Dr. Jackie