Below are two examples of EEG toys.

STAR WARS FORCE TRAINER by Milton Bradley ($30 - $50 USD)

-Although it's been discontinued due to lack of sales, a lot are being sold at a low price on Amazon, eBay etc.

-With this toy, you put on your EEG headset and one channel of brain activity over your frontal lobe is then collected. The electrodes behind the ears are simply used as reference and ground. What kind of electrodes are these you may ask? They are based off of NeuroSky chips (https://en.wikipedia.org/wiki/Comparison_of_consumer_brain–computer_interfaces). If you are able to focus and increase attention, the ping pong ball in the tube rises as the fan at the base increases in speed. If you relax, the ball falls towards the bottom. Yoda's voice acts as a guide along the way to becoming a Jedi. What more could you ask for?

MIND FLEX by Mattel ($30 - 50)

-This toy allows you to put your brain to test as you change your brain states to go through an obstacle course.

Once you have your own EEG toy, now it's time to open it up and hack it.

Hacking Star Wars Toy:

http://www.instructables.com/id/How-to-hack-EEG-toys-with-arduino/

Hacking the MindFlex:

http://frontiernerds.com/brain-hack

SOLDERING TIPS:

When soldering the ground wire for the Star Wars toy. There doesn't appear to be a lot of room if you try soldering onto the board inside the headset, since there's already a wire soldered there. Instead, you can solder directly onto the backside of the battery pack, where the negative end is.

As for the Mindflex, again same problem. Not a lot of space to solder onto the pre existing wires. Find the separate GND pin and solder your wire there instead.

SERIAL COM with ARDUINO UNO (R3)

Where to buy and specs: https://www.sparkfun.com/products/11021

Connect your Arduino to the computer with the USB serial cable.

Download the Brain Arduino library developed by kitschpatrol: https://github.com/kitschpatrol/Brain

-Brain is an Arduino library for parsing data from Neurosky-based EEG headsets.

-Tested units include the Star Wars Force Trainer and Mattel Mindflex.

-It is designed to make it simple to send out an ASCII string of comma-separated values over serial, or to access processed brain wave information directly into your Arduino sketch.

Open up the 'BrainSerialTest' example in the Brain library folder. Run as is and you will see 3 values printed per sec (Signal Quality, Attention, Meditation).

If Signal Quality is 0 = GOOD CONNECTION

If Signal Quality is > 0 = Poor connection

For our visualization code, we filtered the data by only taking in data if the signal quality was zero.

Once you something like this, then it's time to move onto the visualization code!

WIRELESS COM win ARDUINO LIGHT BLUE BEAN

Where to buy the bean, info and specs: http://legacy.punchthrough.com/bean/

For this example, no wires are necessary to connect to the computer, as the communication is over wireless bluetooth.

This time, open up the 'BrainSoftSerialTest' example under the Arduino Brain library, mentioned in the above example. Change the code to match the below example and then run once you are connected through the bean loader.

Once see data output in the serial monitor, you are now ready for the final step!

To view some cool visualizations of your brain waves IN REAL TIME, click here to download our code and see the inspiration behind it:

http://hackthegap.emilylyman.com/

For technical details of downloading the code, see build instructions below.

You should see something like this. Blue represents relaxation and red represents attention.