Brain computer interface based assistive device

The human brain is one of the most complex structures of the universe. Numerous experiments and studies have been carried out on it to analyze its characteristics. As a result of the availability of high-speed electronics and efficient algorithms, various efficient Brain Computer Interface devices have been developed. The dry electrode based Brain Computer Interface device implemented here belongs to the class of non-invasive Brain Computer Interfaces. It is meant to assist people with speech impediments by giving them the ability to call a person in situations they need help. Electrophysiological signals generated by the brain can be divided into three categories- specific frequency components of electroencephalography produced spontaneously during the process of thinking , such as alpha waves , beta waves and so on; brain evoked Event Related Potentials(ERP), i.e. neural electrical activity of cerebral cortex induced by specific sensory stimulus or event operation; the third is the set of signals of neurons directly acquired by a detection electrode implanted into the specific region of the brain cortex. In this work the second type, i.e. ERP signals are employed for implementing the various functionalities of the Brain Computer Interface.