Effective connectivity of brain regions related to visual word recognition: An fMRI study of Chinese reading

Abstract

Past neuroimaging studies have focused on identifying specialized functional brain systems for processing different components of reading, such as orthography, phonology, and semantics. More recently, a few experiments have been performed to look into the integration and interaction of distributed neural systems for visual word recognition, suggesting that lexical processing in alphabetic languages involves both ventral and dorsal neural pathways originating from the visual cortex. In the present functional magnetic resonance imaging study, we tested the multiple pathways model with Chinese character stimuli and examined how the neural systems interacted in reading Chinese. Using dynamic causal modeling, we demonstrated that visual word recognition in Chinese engages the ventral pathway from the visual cortex to the left ventral occipitotemporal cortex, but not the dorsal pathway from the visual cortex to the left parietal region. The ventral pathway, however, is linked to the superior parietal lobule and the left middle frontal gyrus (MFG) so that a dynamic neural network is formed, with information flowing from the visual cortex to the left ventral occipitotemporal cortex to the parietal lobule and then to the left MFG. The findings suggest that cortical dynamics is constrained by the differences in how visual orthographic symbols in writing systems are linked to spoken language.

From regions to connections and networks: new bridges between brain and behavior

“…Interest in modeling inter-regional connectivity has driven the development of new statistical techniques, as well as the application of established techniques from other fields [15*], including structural equation modeling, partial least squares, psychophysiological interactions and dynamic causal modeling. These techniques have demonstrated that functional interactions among brain areas are involved in a wide range of cognitive domains and correlate with performance, including cognitive control [16, 17], learning [18*], memory [19], attention [20], reward processing [21] and language [22]. Connectivity-based biofeedback studies have demonstrated that participants can be trained to self-regulate specific functional connections, resulting in desirable behavioral changes, such as increased subjective emotional valence ratings [23].…”

Psychology and Philosophy of Abstract Art

“…Whilst the ways in which general activity of visual perception may, or may not, be exactly the same as the visual perception of specifi c piece of two-dimensional abstract art, such integrative activities are most surely similar. An example of perceptual complexity and integration is provided in a recent study that looked specifi cally at the handling by specialized neural regions in the processing of various orthographic aspects and semantic components of Chinese characters (Xu et al 2015 ). The authors cite how earlier neuroimaging studies into word recognition identifi ed functions within specifi c neural systems but that more recently studies have considered the integration and interaction of important aspects of distributed neural systems when considering visual word recognition (Xu et al 2015 ).…”

“…An example of perceptual complexity and integration is provided in a recent study that looked specifi cally at the handling by specialized neural regions in the processing of various orthographic aspects and semantic components of Chinese characters (Xu et al 2015 ). The authors cite how earlier neuroimaging studies into word recognition identifi ed functions within specifi c neural systems but that more recently studies have considered the integration and interaction of important aspects of distributed neural systems when considering visual word recognition (Xu et al 2015 ). The authors suggest that this indicates the processing of languages that have an alphabet employ both the dorsal and ventral neural pathways that originate from the visual cortex.…”

Neural correlates and functional connectivity of lexical tone processing in reading

“…In the auditory domain, a large number of neuroimaging studies have revealed that lexical tone pro-cessing in speech is subserved by a bi-lateralized cortical network involving superior temporal regions, inferior prefrontal regions and the insula (Chang, Lee, Tzeng, & Kuo, 2014;Gandour et al, 2000;Hsieh, Gandour, Wong, & Hutchins, 2001;Klein, Zatorre, Milner, & Zhao, 2001;Kwok et al, 2016Kwok et al, , 2017Liang & Du, 2018;Liu, Peng, et al, 2006;Luo et al, 2006;Nan & Friederici, 2013;Ren, Yang, & Li, 2009;Schremm et al, 2018;Wong, Parsons, Martinez, & Diehl, 2004, Xi, Zhang, Shu, Zhang, & Li, 2010Yu, Wang, Li, & Li, 2014). Several studies have also illustrated left-lateralized connectivity network for lexical tone processing in speech (Ge et al, 2015;Xu, Wang, Chen, Fox, & Tan, 2015;Yang, Gates, Molenaar, & Li, 2015). In the visual domain, phonology has a role in activating word meanings in skilled silent reading (Coltheart, 2000;DeMarco, Wilson, Rising, Rapcsak, & Beeson, 2017;Jared, Levy, & Rayner, 1999;Ryherd et al, 2018;Tan & Perfetti, 1999), and thus, it is reasonable to postulate the contribution of lexical tone phonology to visual word recognition.…”