Non-acoustic speech recognition and reconstruction has a number of potential applications including speech rehabilitation and communication in noisy and covert environments. In this project we intend to focus on developing speech restoration systems appropriate for patients who have lost function in parts of the vocal apparatus, such as those who have had a laryngectomy as a result of throat cancer, trauma, destructive throat infections or damage to the nerves or those with other conditions which make speech difficult. Initially laryngectomy patients will be considered but in the long term, we would seek to consider a broader range of conditions such as dysarthria associated with cerebral palsy.
The essence of the proposed system, is that by
monitoring the motion of elements of the vocal apparatus, it is
possible to determine the speech sounds that an individual wishes to
produce. An example of such a system might involve a number of small
magnets implanted into the appropriate parts of the client’s mouth (eg
lips, tongue and teeth). These will produce a variation in the
magnetic field surrounding the mouth during ‘speech’. By monitoring
these variations in the magnetic field and comparing them with
statistical models of the signals for a chosen
vocabulary, it is proposed that the best matching sound may be
identified. It is envisaged that the implants would be small enough
that they would not be apparent when observing the client and would
not affect the movement of the mouth. The implants used in the ideal
system are expected to be 1-2 mm in size and, where appropriate,
coated with a biocompatible material, eg silicone. These may
be concealed in the teeth of dentures, or implanted in, or stuck to,
the posterior surface of the incisors using standard dental
techniques, so that they are hidden from view. Implants may be
placed into the soft tissues by an injection technique under local
anaesthetic. It is envisaged that the motion sensing system would be
incorporated into the client’s normal attire, for example, as part
of a pair of glasses, a tie or a necklace.