Silent Speech

Imagined speech (also called silent speech, covert speech, inner speech, or, in the original Latin terminology used by clinicians, endophasia) is thinking in the form of sound – "hearing" one's own voice silently to oneself, without the intentional movement of any extremities such as the lips, tongue, or hands. Logically, imagined speech has been possible since the emergence of language, however, the phenomenon is most associated with its investigation through signal processing and detection within electroencephalograph (EEG) data as well as data obtained using alternative non-invasive, brain–computer interface (BCI) devices.