Alzheimer's Intervention With Arduino and MindFlex

My partner and I listened to a podcast in which an MIT professor explained some research that she's doing. Here is a simplified version of the thought process that lead us to this project.

Dr. Tsai explained that in a non-Alzheimer's brain, gamma frequency brain waves trigger glial cells to clean up beta amyloid plaques. When this process fails, plaque builds up and causes Alzheimer's symptoms.

Dr. Tsai obtained mice with transparent skulls and brains that were sensitive to light. She blinked a light at the gamma frequency (~40Hz) and the glial cells cleaned up the plaques and reversed the Alzheimer's symptoms.

But, humans don't have transparent skulls or light sensitive brains, so she thought that there's another way for light to get to the brain...through the eyes. So, she made LEDs blink at the gamma frequency and that also triggered glial cells to clean up plaques in mice.

But, these frequencies of blinking light can trigger seizures or cause motion sickness in humans, so it wasn't a practical method to use therapeutically.

My partner and I thought that there are other ways to get frequencies to the brain such as sound and touch. So, our goal was to build a motor that vibrates on the skin at gamma frequencies and produce a sound that matches gamma frequencies and then test to see if the brain produces more gamma waves (that would presumably (but we couldn't verify) trigger glial cells to clean up plaques).

Our project ended up winning at the school, district, state, and international science fairs and below, we'll explain to you how we did it.

Mindflex headset

2 Arduinos

DC motor and arduino motor controller

Old sunglasses

A few LEDs and resistors

Go-Pro chest mount (or a couple of straps to build your own)

Function generator app and headphones

Our first step was to build an EEG to see if brain waves increased. Fortunately for us, there was an Instructable how to do that. We followed the directions to the Instructable here: https://www.instructables.com/Mini-Arduino-Portable-EEG-Brain-Wave-Monitor-/

We modified the code slightly to focus on just Gamma brain waves, but otherwise followed the directions exactly. At the end of our project, we went to the Hemet Hospital and used a real EEG to confirm our results and we got very similar results to the EEG that we built ourselves.

To confirm that our EEG was working, we created sunglasses that blink an LED at 40 Hz. We know for sure that light activates gamma brain waves, so if this doesn't work, then our EEG isn't working properly.

We connected two LEDs to resistors and to an Arduino similar to the diagram below from the Arduino website.

And we modified this sample code from the arduino website to blink the LEDs at the right frequency.

// the setup function runs once when you press reset or power the board

void setup() {

 // initialize digital pin LED_BUILTIN as an output.

 pinMode(LED_BUILTIN, OUTPUT);

}

// the loop function runs over and over again forever

void loop() {

 digitalWrite(LED_BUILTIN, HIGH);  // turn the LED on (HIGH is the voltage level)

 delay(12.5);            // wait for 1/80th of a second

 digitalWrite(LED_BUILTIN, LOW);  // turn the LED off by making the voltage LOW

 delay(12.5);            // wait for 1/80th of a second

}

This did not generate a perfect 40 Hz blink rate, but gamma waves are anywhere between 30 and 80 Hz. Dr. Tsai used 40 Hz so we just tried to be close to that.

Then, we just hot-glued the LEDs into the glasses and turned the lights off during the experiment so that the LEDs were the dominant light source.

Then, we connected a DC motor to an arduino and a motor controller. We put off balance weights on the shaft of the motor to make it vibrate as it spins. We put a piezo disk on the wood plank to connect to an oscilloscope to calibrate the motor but this isn't required. You can also use the slow motion feature on your phone camera.

My partner eventually made a vibrating chair that vibrated at a frequency of 40 Hz and you can hear him talk about that in the YouTube video at the end of this Instructable. For our research, we used the chest-mounted version of the vibration device.

The connections were made based upon this diagram from the Arduino website but using only 1 motor. You cannot power these motors through the Arduino board, you must use an external battery. The size of your motor will determine the size of the battery needed. We used a spare FTC robotics battery.

And we used this code from the Arduino website to control the speed (modified for a single motor):

int motor1pin1 = 2;

int motor2pin1 = 4;


void setup() {
  // put your setup code here, to run once:
  pinMode(motor1pin1, OUTPUT);
  pinMode(motor1pin2, OUTPUT);

  pinMode(9, OUTPUT); 
}

void loop() {
  // put your main code here, to run repeatedly:   

  //Controlling speed (0 = off and 255 = max speed):
  analogWrite(9, 100); //ENA pin

  //Controlling spin direction of motors:
  digitalWrite(motor1pin1, HIGH);
  digitalWrite(motor1pin2, LOW);
  delay(1000);

  digitalWrite(motor1pin1, LOW);
  digitalWrite(motor1pin2, HIGH);

  delay(1000);
}

The sound step was pretty easy. We used a frequency generator app and headphones. Nothing special. Because most headphones cannot reproduce a 40 Hz sine wave, we used a 20 Hz square wave because headphones can click 40 times per second. We used the oscilloscope again to confirm the frequency. You can see the little oscilloscope board in the photo above from the hospital.

My partner, who is known as TannerTech on YouTube and Instructables (https://www.instructables.com/member/tanner_tech/instructables/) made this YouTube video about our research. Check it out here as well as all of the other AMAZING things he does while attending MIT.

https://youtu.be/RSs1vlshcjQ

We proved that we could use sound, light, and vibrations to trigger gamma waves in the brain (vibrations worked the best). But, the limitation of this technique is that the sound produced gamma waves in the auditory portion of the brain, but that's not where Alzheimer's lives. We had no way to prove if those gamma waves produced a glial response anywhere else in the brain as our EEG was a whole brain device and an FMRI would be needed to confirm this. Dr. Tsai is now working with magnetic fields to penetrate deep in the brain to reach the Hippocampus where Alzheimer's damage causes the most problems. Keep an eye on her research and thanks for reading about our adventure!