BRAIN COMPUTER INTERFACE (BCI) RESEARCH CENTER AT SRM UNIVERSITY

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1 BRAIN COMPUTER INTERFACE (BCI) RESEARCH CENTER AT SRM UNIVERSITY INTRODUCTION TO BCI Brain Computer Interfacing has been one of the growing fields of research and development in recent years. An Electroencephalograph (EEG) based Brain Computer Interface (BCI) provides a new communication channel between the human and a computer. For generations, humans have fantasized about the ability to communicate and interact with machines through thought alone or to create devices that can peer into a person s thoughts. These ideas have captures the imagination of humankind in the form of ancient myths and modern science fiction stories. However only in recent decades have advances in neuroscience and brain sensing technologies which allow us to monitor the physical processes within the brain that correspond with certain forms of thought. A brain-computer interface uses electrophysiological signals to control remote devices. They consist of electrodes applied to the scalp of an individual which pick up the brain s electrical activity (at the microvolt level) and carry it into amplifiers. These amplifiers amplify the signal approximately ten thousand times and then pass the signal to a computer for processing. The computer processes the EEG signal and uses it in order to accomplish tasks such as communication and control. Brain Computer Interfaces are slow in comparison with normal human actions, because of the complexity and noisiness of the signals used, as well as the time necessary to complete pattern recognition and signal processing. The phrase Brain-Computer Interface (BCI) when taken literally means to interface an individual s electrophysiological signals with a computer. A true BCI only uses signals from the brain and as such must treat eye and muscle movement as artifacts or noise. Brain Computer interfacing technology is most useful as a communication device if the system is capable of discriminating at least two states within the user. With this ability, a computer can translate the transitions between states or the persistence of a state into a form that is appropriate for controlling an application.

2 HARDWARE COMPONENTS An EEG Machine We used the Nasan Medicals NeuroSpy PC based video EEG system. The system records and enables review of the subject s electroencephalogram. The distinctive feature of NeuroSpy is the full frequency response of 0.1Hz to 70Hz. NeuroSpy is a Windows based digital EEG machine. It has facility to save 24Hrs of EEG data and video images. Other features include : o Easy to use GUI o Simultaneous acquisition of 21 EEG channels. o Facility to change montages during acquisition and in review mode and can have user configurable montages. o Facility to mark the pages for printing during acquisition as well as review. o Facility to mark standard and user annotated events during acquisition and edit them in review and to view next/previous marked events. o Spike Detection facility. o Facility to review the same test or another test during acquisition. o Facility to view and print different amplitude and frequency brain maps. System Configuration o Processor o RAM o Serial Port o Hard Disk - Dual-processor Pentium IV PC 3.00 GHz - 1 GB RAM - RS 232 Serial port for EEG amplifier - 80 GB HDD o Graphics Adapter - SVGA compatible o Monitor - Resolution 1024 x 768

3 o Other Specifications Independent earth connection, Speakers, Microphone, 17 color monitor, CD writer, Keyboard and Mouse. WORKING ENVIRONMENT Since the projects is mainly dependent on the user or the subjects ability to generate a particular wave and our skills to classify the same it is essential for the user to be tested in a sterile and distraction free environment. Though it is clear that the brain always multitasks and we can do little to avoid it except maybe reduce further environmental based stress. The following amenities are present in our lab: o Free and un-congested space o Clean, Fresh-air supply o Completely noise proof o No external disturbances such as creaking floors, squeaking doors etc. SOFTWARE COMPONENTS The following software were used for the successful completion of the project o NeuroSpy EEG 6.5 o NeuroSpy FFT 6.5 o Microsoft Office o Microsoft Windows XP - Software accompanying the EEG - Complementary Software for getting the FFT of EEG graphs. - Documentation and Data Storage - Literature Survey and Documentation o Microsoft Windows 2000 Professional - EEG compatible OS. o MATLAB 7.0 o EEGLAB

4 FUTURE REQUIREMENTS The future requirements for better analysis and results and for future growth and development include: o A Magneto Encephalogram Machine (MEG) o A Magnetic Resonance Imaging Device (MRI) o An upgraded EEG hardware o Compatible EEG software which has robust interface with open sources such as EEGLAB, BCILAB, BCI2000 etc. PROJECTS CARRIED OUT AT SRM-BCI RESEARCH CENTER 1. Feasibility study for implementing BCI using EEG 2. Thoughts and related waveform categorization 3. Color Meditation Effect of Blue color on Human thought and its side effects 4. Design of an EEG based Emotion Recognition System An Application to Music Therapy 5. Real-time BCI-Based Target Selection - 2-D Cursor Control

5 The System of Electrode Placement. Comparison of alpha, beta, theta and delta rhythms.

6 BCI Lab at SRM An experiment with a Subject, EEG at Background Neurospy software Analog Signals from EEG