1. Biofeedback and Stress Management BME 402 Spring 2004

3. Team Members  Eric Miller  Christopher Valley  Erik Birkeneder  Kevin Kinney Advisor - Client  Mitchell E. Tyler  Dr. Dan Muller

4. Overview  Problem Statement  Background  Last Semester’s Progress  Improvements  Budget  Future Work  Thank You

5. Problem Statement Design and build an inexpensive, portable electroencephalogram that teaches meditation practitioners to achieve optimal meditation states by the presence of EEG alpha and theta waves.  Design an effective electrode setup  Design brain wave detection circuitry  Design optimal feedback mechanism

6. Background  Beta State  13 – 40 Hz  Alertness, Concentration,  Cognition  Alpha State  8 – 13 Hz  Relaxation, Visualization,  Creativity Meditation States

7. Background  Theta State  4 – 7 Hz  Meditation, Intuition, Memory  Delta State  0 – 7 Hz  Detached awareness, Healing, Sleep Meditation States

8. Last Semester’s Progress Labview Program  Acquisition and Recording of Data  Allows historical analysis of a complete meditation session  Can determine percentage of time spent in desired frequency states  Allows easy testing of different feedback mechanisms without manipulating a analog circuit

9. Labview Computer Model Block Diagram Electrodes Low pass filter (f c = 50 Hz) Amplifier (15000 gain) Meditation Practitioner Labjack Data Acquisition Visual feedback Power Spectrum vs. time Power Spectrum (  awake) Filters ( , awake) Audio feedback - analog - analog - digital - digital

10. Improvements  Electrode Focus  Previous semester’s design unreliable  Signal extremely corrupted by motion artifact  Headband limited configuration capabilities  Electrode Design  Grass-Telefactor Electrodes Ag/Ag-Cl  Disposable ECG Electrodes --2 mm Hole --10 mm Cup Diameter

11.  Electrode Placement  Configuration 1  2-occipital, 1-mastoid  Configuration 2  2-occipital, 1-frontal  Configuration 3  2-mastoid, 1-frontal  Configuration 4  Gave Best Results  All 3 frontal Improvements

12. Electrode Results  Sample EEG 1 ~36 Hz  Christopher Awake

13. Electrode Results  Sample EEG 2 ~10 Hz  Christopher Sleeping

14. Proposed Portability Solutions  Portability Options  FPGA  Microcontroller (MCU)  Microprocessor (DSP)  PDA

15.  Processor Requirements  Real time analysis  Affordable  Flexible Programming  Possible Solutions  DSP  MSP430 MCU - ?  PDA/PC Proposed Portability Solutions

16. Current Costs Components$Cost$ Grass Telefactor Electrodes$121.00 Preparation Materials $20.00 to $40.00 Processor Development Kit: $3,500 Cost/Unit: $1.40 Total Initial Development: $3680 Total/Unit: ~$57.40

17. Future Work  Reconfiguration of Algorithm in LabView  Feedback options testing  University Resources for Development Kit  Program the DSP processor  Test device

18. Thank You  UW Hospital EEG Clinic  Sheila Franzosa  W. Keck Laboratory  Richard Davidson  Isa Dolski