Introduction<br />It is the study of brain functions<br />BCI are system that provide translation of the electrical activity of the human brain into command which can control device in real time.<br />An Electroencephalogram based Brain-Computer-Interface (BCI) provides a new communication channel between the human brain and a computer.<br />
Applications <br />Bioengineering applications: assist devices for disabled people.<br />Human subject monitoring: sleep disorders, neurological diseases, attention monitoring, and/or overall "mental state".<br />Neuroscience research: real-time methods for correlating observable behavior with recorded neural signals.<br />Man – Machine Interaction: Interface devices between human and computers, machines.<br />
History- Discovering the Basics<br />1924: Hans Berger discovers the EEG<br /> Analyses the interrelation of EEG and brain diseases.<br />1970: First developments to use brain waves as input<br />ARPA has vision of enhanced human<br /> First step in the right direction<br />
History-Monkey first<br />1990: First successful experiments with monkeys<br />Implanting electrode arrays into monkey brains<br />Recording of monkeys‘ brain waves<br />2000: Monkeys control robots by thoughts<br />
History - … Humans follow<br />More non-invasive than invasive approaches<br />Brain reading by eg. EEG, MEG or fMRI<br />2004: First human benefits from research<br />
KEY ISSUES IN BCI RESEARCH AND USERS<br />RESEARCH DISCIPLINES<br />Engineering<br />Clinical ...<br />Psychological<br />Neuroscience<br />
KEY ISSUES IN BCI RESEARCH AND USERS<br />Target users:<br /><ul><li>Researchers - clinical researchers, neuroscientists, signal processing experts, etc.
Technical operators - caregivers, therapists who are in charge of training someone on BCI operation.
End-users -people with disabilities who rely on the system for communication
Casual end-users -those who use a BCI as an alternative input for entertainment devices.</li></li></ul><li>What is BCI<br />Brain-Computer Interfaces (BCI) <br />Interaction between the human neural system and machines<br />Goal<br />Enabling people (especially disabled) to communicate and control devices by mere thinking.<br />BCI is a control system <br />
Structure of a BCI<br />1) Signal Acquisition: the EEG signals are obtained from the brain through invasive or non-invasive methods (for example, electrodes). After, the signal is amplified and sampled.<br />2) Signal Pre-Processing: once the signals are acquired, it is necessary to clean them.<br />3) Signal Classification: once the signals are cleaned, they will be processed and classified to find out which kind of mental task the subject is performing.<br />4) Computer Interaction: once the signals are classified, they will be used by an appropriate algorithm for the development of a certain application.<br />
Signal Processing<br />Feature Extraction<br />The Translation Algorithm <br />
Output Device<br />Any controllable machines<br />For answering yes/no questions<br />For word processing <br />Wheelchair<br />Virtual Reality<br />Usually, Computer screen and the output is the selection of targets or cursor movement<br />
C++ language</li></li></ul><li>Wearable BCI<br />Mobility<br />Communication technologies<br />Bluetooth<br />802.11(wire less –WLAN)<br />GSM/GPRS<br />PDA instead of stationary computer<br />Dry Electrode instead of wet (reducing montage time)<br />Making the BCI transparent<br />No need to change electrodes for a reasonable long time<br />
Characteristics of Brainwaves<br /><ul><li>Theta waves [4, 7.5] associated with reverie, daydreaming, meditation, creative ideas
Delta waves [0,4] Hz associated with deep sleep and in the awake state were thought to indicates physical defects in the brain.</li></li></ul><li>Characteristics of Brainwaves<br /><ul><li>Alpha wave(8-13hz)-its indicates both a relaxed and attention mode of the brain.
Beta wave(13-30 hz)-it is the brain wave usually associated with activity thinking, active attention.</li></li></ul><li>CHARACTERISTICS OF BRAIN WAVES<br /><ul><li>Gamma waves-within 35Hz-it reflect the mechanism of consciousness.
Mu wave(8-12)hz –associated with Motor activity,</li></ul>Mu and alpha waves<br />
Functionality of BCI<br />Steps for the function of BCI.<br />1.user wired to a multi-electrode EEG skin cap, which is connected to a pc running BCI2000.<br />2.user of the signal asked to generate a series of signals.<br />3.EEG potential record and analyze the signal<br />4.the software attempt to match these signal to previous recorded signals.<br />5.at last identified words are wrapped on output devices like-screen or speech synthesizer.<br />
Risk factors and alternate solution<br /><ul><li>Undergone through hurdle brain surgery.
Glasses and Lasik operation is best options.</li></li></ul><li>Current Projects<br />Berlin Brain-Computer-Interface<br />Joint Venture of several German research organisations<br />Supported by the Ministry of Education and Research<br />Graz Brain-Computer-Interface<br />Wide range of research topics<br />Impressive combination of BCI and FES (Functional Electrical Stimulation)<br />
Can be run on Java-enabled handsets</li></li></ul><li>REFERENCES<br /> <br /> IEEE Xplorer Digital Library website(Through SJCE Server) <br />http://ieeexplore.ieee.org/Xplore<br /> <br /> Wikipedia - internet encyclopedia<br />http://en.wikipedia.org/wiki/Brain-computer_interface<br />