he goal of this project is to create a Biofeedback loop with a computer and a special program which will be connected to a patient and will monitor and analyst his EEG signals.
Abstract
he goal of this project is to create a Biofeedback loop with a computer and a special program which will be connected to a patient and will monitor and analyst his EEG signals , and will help the patient change his mental state which is by definition not controllable . In this project we used the complexity of the brain signal extracted from the EEG as datum for feedback, using an algorithm first published by Grassberger P. & Procaccia I . and later investigated by Otakar Fojt. & Jiri Holcik in “Applying Nonlinear Dynamics to ECG Signal Processing” (IEEE, 1998).
Introduction : Brain signals and Biofeedback
Introduction : Brain signals and Biofeedback.
Project overview
The project is based on some preliminary hardware in order to measure the brain signals ,and a mathematical software (Matlab) in order to analysis and display the correlation dimension In real time For the patient as a Biofeedback .
The hardware part includes : differential electrodes connected to
The patient , a linear amplifier , A/D card and a computer :
The Software part was written in Matlab and includes:
The software runs at cycles of 1 sec. Each cycle it builds a new data vector , scales it , builds a space-state matrix and clears it using SVD process . Then it runs a calculating procedure in order to figure the correlation dim.
The calculating procedure is a loop that calculates distances between vectors:
Results and Conclusions
The tests that toke place showed that there is a change in the complexity of the brain waves due to the use of the Feedback And that the Biofeedback instrument can be used to alter the mental and stress state of the patient connected to it.
EEG complexity right figure–EEG complexity with BioFeedback without Feedback
Acknowledgments
We would like to thank our supervisor Elad Yom-Tov for his help and Patience.