Zusammenfassung
This review summarises the status of silent speech interface
(SSI) research. SSIs rely on non-acoustic biosignals generated by
the human body during speech production to enable communication
whenever normal verbal communication is not possible or not
desirable. In this review, we focus on the first case and present
latest SSI research aimed at providing new alternative and
augmentative communication methods for persons with severe speech
disorders. SSIs can employ a variety of biosignals to enable
silent communication, such as electrophysiological recordings of
neural activity, electromyographic (EMG) recordings of vocal
tract movements or the direct tracking of articulator movements
using imaging techniques. Depending on the disorder, some sensing
techniques may be better suited than others to capture
speech-related information. For instance, EMG and imaging
techniques are well suited for laryngectomised patients, whose
vocal tract remains almost intact but are unable to speak after
the removal of the vocal folds, but fail for severely paralysed
individuals. From the biosignals, SSIs decode the intended
message, using automatic speech recognition or speech synthesis
algorithms. Despite considerable advances in recent years, most
present-day SSIs have only been validated in laboratory settings
for healthy users. Thus, as discussed in this paper, a number of
challenges remain to be addressed in future research before SSIs
can be promoted to real-world applications. If these issues can
be addressed successfully, future SSIs will improve the lives of
persons with severe speech impairments by restoring their
communication capabilities.
Nutzer