Hardly an instructable all I did was change two numbers in the Arduino example code "Blink"
I changed it to 25 on and 25 off. I read charlesS229 calculated 13 on 12 off. Not sure which way to go on that so maybe try both?
Other examples of Alzheimer's Light Therapy are here
Research is here
I should point out that this was only done on mice so far and the light therapy probably only affected the visual cortex. Perhaps other areas of the brain could be affected by a 40 mz signal using sound thru speakers or head phones, bone conduction and magnetism. Maybe pop a couple iron pills and slap a coil on your head? Even a vibrating mat or chair may work. The important thing here seems to be this 40 Mz signal seems to break up the plaque that builds up in the brain and shorts out your memories and thoughts. Anything is worth a try.
Pardon the upside down pic.
That is it. Use an appropriate resistor and LED. Modify the blink sketch found in the Arduino IDE, upload it to any suitable Arduino, attach your resistor between the LED negative leg and ground. Attach the LED positive leg to pin 13 then power up your Arduino. I suggest placing it somewhere in the field of view by some flowers or something that attracts the eye like a picture or TV. Use a breadboard and jumpers or solder and wire to attach your components.