View source for Evoked Potential Eye Mask

==Summary==
The most basic concept that can explain an evoked potential device is that of a warm crackling fire: The calming effect of sitting in front of the fireplace, watching the flames flicker, hearing the sound, and feeling the pulsing heat all in tune of the same rhythm. One of the reasons for this effect (not discounting the many other psychological associations, basic warmth, etc.) is [http://en.wikipedia.org/wiki/Evoked_potential Evoked Potential], the natural tendency of the brain to fire in sync with its sensory surroundings. Odds are good that fire is flickering at a slow 4-12 Hz, the [http://en.wikipedia.org/wiki/Theta_wave Theta] and [http://en.wikipedia.org/wiki/Alpha_waves Alpha] ranges associated with calm relaxation.

The goal of this project is to build a device that can induce these brain wave states using flashing LEDs and pulsing audio. Many other examples of this concept are currently out in the world, but one example near to the hearts of many in the Maker community is the Make [http://blog.makezine.com/archive/2008/12/the_brain_machine.html Brain Machine] by [http://www.tvbgone.com/cfe_mfaire.php Mitch Altman].<br> The design goals of this model are as follows:
# Soft wearable design suitable for sleeping such as a face mask.
# Self programmable using a simple computer interface.
# Multiple programs stored on device for easy selection and playback.
# Rechargeable batteries.
# Option to plug in your portable music player and play over the pulsing beats. (reduces effectiveness but more pleasurable)
# Electronics removable for washing.

The chosen platform for the electronics is the [http://www.arduino.cc/en/Main/ArduinoBoardLilyPad Lilypad Arduino] microcontroller board. After some experimentation with the open source Mitch Altman design I estimate that the ATMega328 controller will be overkill for this design, but will afford many future enhancement possibilities.


&copy; Designs and Code under this project distributed under Creative Commons 3.0 Attribution Share-Alike License<br> http://creativecommons.org/licenses/by-sa/3.0/

==Materials==
1 x LilyPad Arduino Mainboard [http://www.sparkfun.com/commerce/product_info.php?products_id=9266 SparkFun DEV-09266]<br />
1 x FTDI-based USB Arduino programmer (I have an Arduino [http://www.arduino.cc/en/Main/MiniUSB MiniUSB] which works with some minor [http://web.media.mit.edu/~leah/LilyPad/01_comp_attach_text2.html#soldering adjustments].) UPDATE: Those instructions are old. For the new 6pin Lilypad you need to also connect a CTS and DTR pin from the MiniUSB.<br />
1 x LilyPad LiPower [http://www.sparkfun.com/commerce/product_info.php?products_id=8786 SparkFun DEV-08786]<br />
1 x LiPoly Charger - Single Cell 3.7-7V Input [http://www.sparkfun.com/commerce/product_info.php?products_id=726 SparkFun PRT-00726]<br />
1 x Polymer Lithium Ion Batteries - 1000mAh [http://www.sparkfun.com/commerce/product_info.php?products_id=339 SparkFun PRT-00339]<br />
1 x Spool of Conductive Thread - 234/34 4ply [http://www.sparkfun.com/commerce/product_info.php?products_id=8549 SparkFun DEV-08549]<br />
1 x Surface Mount Navigation Switch [http://www.sparkfun.com/commerce/product_info.php?products_id=8184 SparkFun COM-08184]<br />
8 x Triple Output SMD LED RGB [http://www.sparkfun.com/commerce/product_info.php?products_id=7844 SparkFun COM-07844]<br />
4 x 4.7K SMD resistors (LEDs)<br />
2 x 2.7K SMD resistors (Audio)<br />
7 x 10K resistors (audio mixer and Selector switch)<br />
2 x 1&mu;F SMD Capacitors <br />
1 x Stereo Headphone Jack [http://www.radioshack.com/product/index.jsp?productId=2103452 RadioShack 274-249]<br />
1 x Cheap set of headphones<br />
1 x Eye mask ([http://www.ehow.com/video_4404865_making-pattern-sewing-sleeping-mask.html Make Your Own]) I envision 3 layers of fabric. A soft sheer inner lining, an outside fabric with the color of your choosing, and a center circuit-fabric layer. Velcro could be used to hold the layers together for easy disassembly/washing<br />

==Design==
[[EPEM Source Code]]<br />
[[EPEM Schematics]]<br />

==Links==
[http://web.media.mit.edu/~leah/LilyPad/index.html LilyPad Home]<br />
[http://www.arduino.cc/cgi-bin/yabb2/YaBB.pl?num=1260037835 Arduino Forum: How to implement a soft-reset button]<br />
[http://www.hackcanada.com/homegrown/wetware/brainwave/ BrainWave Machines]<br />
[http://www.tkk.fi/Misc/Electronics/circuits/linesum.html Simple Mixer Circuit]<br />
[http://code.google.com/p/theentropyworks/ TheEntropyWorks SLM Mod]