A Systematic Review on EEG Signal Processing for Imagined Speech Recognition

Abstract

Imagined speech is the inner pronunciation of words (unspoken speech, silent speech, or covert speech) without emitting sounds or making movements of face. Speech is the simple, normal and effective way people can communicate with one another. But some brain injuries caused by brain stroke, traumatic brain injuries, brain paralyses, stroke and ALS (amyotrophic lateral sclerosis) restrict vocal speech, even when the patient is completely conscious. People that cannot communicate due to neural conditions will benefit from a device that can specifically infer brain impulses from internal expression. For this speech impaired population, Brain Computer Interface(BCI) may be a possible communication alternative. A Brain Computer Interface that uses brain impulses to manipulate electronic equipment by a detection of complex variations of brain electrical activity needs to be applied in order to provide quiet communication skills between the two individuals to gather data relating to imaginary talk. This study document focuses on BCI research on the identification of imagined expression and explanations of end-to-end EEG signal processing methodology.