EEG shows brain can simultaneous encode two speech streams

Researchers using EEG recordings found that the brain simultaneously encodes two competing speech streams during attention switching, with the neural tracking of a new speech stream emerging before the listener fully disengages from the previous one. The study, conducted in a multi-talker environment, reveals that attention switching involves asymmetric disengagement and engagement processes accompanied by changes in brain alpha power, and that listeners may reset their lexical context after shifting attention. These findings provide insights into how the brain flexibly processes speech in complex listening environments.