Your ear has about 15,000 tiny hair cells that act like microphones picking up every sound. Each one sends signals to your brain.
When these hair cells get damaged (from noise, age, medication, whatever), they can't send clear signals anymore. The signals become weak and incomplete.
Your brain notices something's wrong. It's trying to hear properly, but the "microphones" are malfunctioning. So what does it do?
It cranks up the internal volume to try and pick up those weak signals.
But here's the problem: the signals are still broken. Your brain's neurons become overactive, desperately trying to fill in the missing sounds. This overactivity creates noise where there shouldn't be, that's called phantom noise. That's the ringing you hear.
Your brain is in a constant state of distress because it's receiving incomplete signals from damaged hair cells. It's like trying to hear someone through a broken phone line and your brain keeps turning up the volume, but all you get is static and noise.
So your brain is literally screaming at itself 24/7, and there's no way to turn it down.
Unless...
The researchers found that 650nm red light wavelength could repair damaged hair cells by stimulating cellular energy production in the mitochondria of those cells. This allows the hair cells to heal and start sending proper signals again.
Once the hair cells are repaired and sending clear signals, your brain doesn't need to overcompensate anymore. The neurons calm down, and no longer creates that phantom noise.