This feels like it belongs in the 1950s, but recently scientists placed these fabric caps that were full of electrodes on elderly patients heads and ran a weak electrical current into their heads. They’d ask patients questions while it was running. Most of the people showed improved memory for a month. Patients with the worst cognitive function to begin with showed the most improvement. The hope is that this could be used in homes to help people that are experiencing dementia.
Have you ever used a TENS unit? They’re used to deliver electrical stimulation to injured or fatigued muscles. I have one at home that has 40 settings like massage or recovery, etc. This sounds like it could be the TENS unit for the brain. Or maybe I could self-test mine. Maybe hook it up behind my ears to help me remember my weekend grocery list better.