Language and motor processing in reading and typing: Insights from beta-frequency band power modulations

Power modulations of the EEG activity within the beta-frequency band were investigated across silent-readingand copy-typing tasks featuring emotionally negative and neutral words in order to clarify the interplay betweenlanguage and motor processing. In reading, a single desynchronization surfaced 200–600 ms after target pre-sentation, with a stronger power-decrease in lower beta frequencies for neutral compared to negative words. Thetyping task revealed two distinct desynchronizations. Afirst one surfaced within spatio-temporal coordinatesclosely resembling those of the desynchronization observed in the reading task, thus pointing towards a commonorigin at the level of linguistic processing of the input word stimuli. Additionally, a second motor-related de-synchronization surfaced during the typed response, from 700 to 2000 ms after stimulus onset. Here, words’emotional connotation affected the higher beta band. The comparison between tasks thus suggests that differentbeta desynchronizations reflect distinct EEG landmarks for language and motor processing. Further, the effect ofemotional connotation on the motor-related desynchronization of the typing task suggests that language pro-cessing can propagate its influence onto the stage of motor response execution, pointing against a serialflow ofinformation from language onto motor processing.