German and U.S.
researchers have decoded natural continuously spoken speech from brain waves
and transformed it into text — a step toward communication with computers or
humans by thought alone. Their “Brain-to-Text” system recorded signals from an
electrocorticographic (ECoG) electrode array located on relevant surfaces of
the frontal and temporal lobes of the cerebral cortex of seven epileptic
patients, who participated voluntarily in the study during their clinical
treatment.
The patients
read sample text aloud during the study. Machine learning algorithms were then
used to extract the most likely word sequence from the signals, and automatic
speech-to-text methods created the text output. The system achieved word error
rates as low as 25% and phone (instances of phonemes in utterances) error rates
below 50%. The researchers suggest that the Brain-to-Text system might lead to
a speech-communication method for locked-in patients in the future.
More
information: