Arduino + LED strip flashing at 40hz for Alzheimers
Inspired by the Radio Lab podcast http://www.radiolab.org/story/bringing-gamma-back/ showcasing the MIT research that reduced beta amyloid proteins in the hippocampus by 50% when mice with early stages of Alzheimer’s were exposed to flickering light at 40hz for an hour.
After recording a slow-motion video at 240fps it turned out there was a delay when using the LED strip, so instead of turning the LED strip on every 12.5ms and off 12.5 ms the current code was adjusted to turn on and off every 10ms, which resulted in the lights flashing 40 times per second / at 40hz. Here is a video of it currently working. Additionally the strip of 60 LEDs is being powered by the Arduino with no external power source: https://www.dropbox.com/s/yunfq8pdprz46qs/40hz%20With%2010ms%20Arduino%20Delay.mp4?dl=0
Warning: This will strobe the LED strip, so do not use it around individuals with epilepsy. The research was only tested on mice and has not been proven to work on humans.
Arduino Uno: $24.95 https://www.adafruit.com/products/50?gclid=CjwKEAiA4dPCBRCM4dqhlv2R1R8SJABom9pHH-xCTzKD9I5WMDmjhv4XvHnBhavM0pzaVjDP1QEMUxoCwyTw_wcB
Adafruit NeoPixel Digital RGB LED Strip - White 60 LED: $24.95 https://www.adafruit.com/products/1138?gclid=CjwKEAiA4dPCBRCM4dqhlv2R1R8SJABom9pHnoW_rBo-baImYlb7MwPGUMsK0nUbw77FqXv4S-zN9xoCYFnw_wcB
Total Cost: $49.9
This project is also possible to accomplish with a standard RGB LED strip instead of an addressable LED strip.
Downlaod and install the Arduino IDE if you do not already have it: https://www.arduino.cc/en/Main/Software Download the Adafruit NeoPixel library: https://github.com/adafruit/Adafruit_NeoPixel Install it by unziping the folder, renaming it to Adafruit_NeoPixel and add it to the Arduino library folder. On Mac it is located under ~/Documents/Arduino/library. If there is no folder named library create one and place the Adafruit_NeoPixel inside it.
Attach the LED strip to the Arduino: Look at the labels closest to the wires to determine the correct pins. +5v and GND should go into the according Pin on the Arduino and the remaining wire(potentially labeled D0) should go into pin 6 on the Arduino. Some LED strips come with 2 extra wires for an external power supply, which are not required. There is sufficient power from the Arduino to light up a strip of 60 LEDs, however if you get a longer strip or would like the LEDs to light up brighter feel free to use an external power supply.
Lastly upload the Flashing_Gamma_Lights.ino to the Arduino: Open Flashing_Gamma_Lights.ino with the Aruino IDE. Make sure Arduino/Genuino Uno is selected under Tools > Board Check the list of devices listed under Tools > Port Plug your Arduino into your computer and select the new board that appears under Tools > Port and you're ready to upload!