Dexin Sun1,2 · Zhilin Zhang1,2,3 · Naoya Oishi4 · Qi Dai3 · Dinh Ha Duy Thuy5 · Nobuhito Abe6 · Jun Tachibana7 · Shintaro Funahashi1,2 · Jinglong Wu1,2 · Toshiya Murai3 · Hidenao Fukuyama1,2,51 Research Center for Medical Artifcial Intelligence, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, China
2 University of Chinese Academy of Sciences, Beijing 100049, China
3 Department of Psychiatry, Graduate School of Medicine, Kyoto University, Kyoto 606-8501, Japan
4 Medial Innovation Center, Graduate School of Medicine, Kyoto University, Kyoto 606-8501, Japan
5 Human Brain Research Center, Graduate School of Medicine, Kyoto University, Kyoto 606-8501, Japan
6 Kokoro Research Center, Kyoto University, Kyoto 606-8501, Japan 7 Speed Reading Academy, Kyoto 600-8439, Japan
Abstract
The activity of occipitotemporal regions involved in linguistic reading processes, such as the ventral occipitotemporal cortex (vOT), is believed to exhibit strong interactions during higher-order language processing, specifically in the connectivity between the occipital gyrus and the temporal gyrus. In this study, we utilized functional magnetic resonance imaging (fMRI) with psychophysiological interaction (PPI) and dynamic causal modeling (DCM) to investigate the functional and effective connectivity in the occipitotemporal network during speed reading. We conducted the experiment with native Japanese speakers who underwent and without speed-reading training and subsequently performed established reading tasks at different speeds (slow, medium, and fast) while undergoing 3-Tesla Siemens fMRI. Our activation analyses revealed significant changes in occipital and temporal regions as reading speed increased, indicating functional connectivity within the occipitotemporal network. DCM results further demonstrated more intricate effective connections and high involvement within the occipitotemporal pathway: (1) reading signals originated from the inferior occipital gyrus (iO), distributed to the vOT and the posterior superior temporal sulcus (pSTS), and then gathered in the anterior superior temporal sulcus (aSTS); (2) reading speed loads had modulation effects on the pathways from the aSTS to vOT and from the iO to vOT. These findings highlight the complex connectivity and dynamic interactions within the occipitotemporal network during speed-reading processes.
Keywords
Speed reading; fMRI; The occipitotemporal network; Functional connectivity; Efective connectivity
