Functional connectivity between parietal and temporal lobes mediates internal forward models during speech production

• Published in: Brain and language Vol. 240; p. 105266
• Main Authors: Zhang, Wenjia, Yang, Fuyin, Tian, Xing
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier Inc 01.05.2023
• Subjects: Auditory; Brain Mapping - methods; Functional connectivity; Humans; Inferior frontal gyrus (IFG); Inferior parietal lobe (IPL); Internal forward model; Motor simulation; Parietal Lobe - diagnostic imaging; Sensory estimation; Somatosensory; Speech; Speech Perception; Speech production; Superior temporal gyrus (STG); Temporal Lobe; Somatosensory; Functional connectivity; Auditory; Inferior parietal lobe (IPL); Superior temporal gyrus (STG); Motor simulation; Sensory estimation; Speech production; Inferior frontal gyrus (IFG); Internal forward model
• ISSN: 0093-934X; 1090-2155
• DOI: 10.1016/j.bandl.2023.105266

•Speech production control requires predicting the sensory consequences of the action.•The motor-based auditory prediction may be mediated by somatosensory estimation.•The inferior parietal lobe (IPL) is a hub linking motor simulation and auditory estimation.•The aIPL and pIPL play distinct roles in the predictive processes during speech production.•Speech tasks modulate the connectivity strength of the cascaded predictive neural network. Internal forward models hypothesize functional links between motor and sensory systems for predicting the consequences of actions. Recently, the cascaded theory proposes that somatosensory estimation in the inferior parietal lobe (IPL) can be a relay computational structure, converting motor signals into predictions of auditory consequences in a serial processing manner during speech production. The study used fMRI with functional connectivity (FC) analyses to investigate the proposed cascaded processes using three speech tasks: overt articulation (OA), silent articulation (SA) and imagined articulation (IA). The FC results showed that connectivity between aIPL and STG was increased in OA compared with SA, suggesting that the relationship between somatosensory and auditory estimations can be modulated by speech tasks. Moreover, stronger connectivity between IFGoper and pIPL, and between pIPL and STG were observed in SA and IA compared with OA. These results are consistent with a cascaded process in the internal forward models.