Commonalities in alpha and beta neural desynchronizations during prediction in language comprehension and production

The present study investigates whether predictions during language comprehension are generated by engaging the production system. We recorded EEG from participants performing both a comprehension and a production task in two separate blocks. Participants listened to high and low constraint incomplete sentences and were asked either to name a picture to complete it (production) or to simply listen to the final word (comprehension). We found that in a silent gap before the final stimulus, predictable stimuli elicited alpha (8-10 Hz) and beta (13-30 Hz) desynchronization in both tasks. Source estimation highlighted not only the involvement of the left-lateralized language network, but also of temporo-parietal areas in the right hemisphere. Furthermore, correlations between the desynchronizations in comprehension and production showed spatiotemporal commonalities in language-relevant areas in the left hemisphere, especially in the temporal, lateral inferior and dorsal frontal, and inferior parietal corteces. As proposed by prediction-by-production models, our results show that comprehenders engage the production system while predicting upcoming words.