This is one of many forms of what are mislabeled neurofeedback.

Roshi, LENS, and others push stimuli into the brain. Some have a history of causing seizures and other 'side-effects.'

They obtain FDA exemption by claiming no risk of negative outcomes but the negative effects are just not reported.

I think PenK's relating of his experience with Brain Wave Optimization is grossly premature. The focus on learning relaxation skills alone can lead to improvements with PTSD. Nothing suggests it helps with PCS.

Don't spend the grocery money doing this.