Brain activity recorded by
electrocorticography (blue circles). From the activity patterns
(blue/yellow), spoken words can be recognized.
Credit: CSL/KIT
"It has long been speculated whether humans may communicate with
machines via brain activity alone," says Tanja Schultz, who conducted
the present study with her team at the Cognitive Systems Lab of KIT. "As
a major step in this direction, our recent results indicate that both
single units in terms of speech sounds as well as continuously spoken
sentences can be recognized from brain activity."
These results were obtained by an interdisciplinary collaboration of
researchers of informatics, neuroscience, and medicine. In Karlsruhe,
the methods for signal processing and automatic speech recognition have
been developed and applied. "In addition to the decoding of speech from
brain activity, our models allow for a detailed analysis of the brain
areas involved in speech processes and their interaction," outline
Christian Herff und Dominic Heger, who developed the Brain-to-Text
system within their doctoral studies. The present work is the first that
decodes continuously spoken speech and transforms it into a textual
representation. For this purpose, cortical information is combined with
linguistic knowledge and machine learning algorithms to extract the most
likely word sequence. Currently, Brain-to-Text is based on audible
speech. However, the results are an important first step for recognizing
speech from thought alone.
The brain activity was recorded in the USA from 7 epileptic patients,
who participated voluntarily in the study during their clinical
treatments. An electrode array was placed on the surface of the cerebral
cortex (electrocorticography (ECoG)) for their neurological treatment.
While patients read aloud sample texts, the ECoG signals were recorded
with high resolution in time and space. Later on, the researchers in
Karlsruhe analyzed the data to develop Brain-to-Text. In addition to
basic science and a better understanding of the highly complex speech
processes in the brain, Brain-to-Text might be a building block to
develop a means of speech communication for locked-in patients in the
future.
A video on the functioning of Brain-to-Text:
http://csl.anthropomatik.kit.edu/publikationen_2934.php
Story Source:
The above post is reprinted from
materials provided by
Karlsruhe Institute of Technology.
Note: Materials may be edited for content and length.