My mom has had declining cognitive function for years, and it got a lot worse last year to the point where she was almost nonverbal.

I put her on a protocol of:

Ultrasound stimulation, 5 minutes 3x per day

Red light therapy, 30 minutes 3x per day

Low dose Methylene blue + magnesium and threonine

Light exercise

Improved ambient lighting conditions removing excess blue light

After 3 months she is starting to initiate and hold conversations again, and already seems to be a lot more 'present' than she was at the start of the year. I was skeptical, but the results have been rather profound, especially given that it's only been a few months.