Distinct Theta Synchrony across Speech Modes: Perceived, Spoken, Whispered, and Imagined

The study on theta-band synchrony across different speech modes provides significant insights into the neural mechanisms of speech production. By analyzing perceived, spoken, whispered, and imagined speech, researchers found that overt and whispered speech are characterized by broader and stronger frontotemporal synchrony, indicating active motor-phonological coupling. In contrast, perceived speech showed dominant posterior and temporal synchrony patterns, aligning with auditory perception and comprehension. Imagined speech, while more spatially confined, revealed internally coherent synchronization primarily involving frontal and supplementary motor regions. These findings not only confirm that theta synchrony varies across speech modes but also contribute to our understanding of language processing, attentional control, and inner speech, which are vital for cognitive neuroscience and related fields.