Abstract:

Constructing a unified cognitive and neurophysiological model is a central issue in cognitive neuroscience studies of visual word reading. Cognitive theoretical models of reading agree that reading results from the division of labor between phonological and semantic processing pathways, and cognitive neuroscience studies have also shown that the reading neural network results from the dynamic collaboration between dorsal and ventral neural pathways. In order to systematically elaborate this dynamic collaboration mechanism of the reading network, the latest research progress is systematically disentangled from the following three aspects by combining the two levels of neural function and physiological basis.

Firstly, it points out that the underlying processing demand is the essence of the dynamic collaboration between the dorsal and ventral neural pathways. Reading different types of words recruits an overlapped neural network, and their differences result from a dynamic interaction between phonological and semantic processing regions. This section reviewed studies that suggest that dynamic changes characterize the activation of reading-related brain regions. The activation of these brain regions is influenced by bottom-up stimulus properties and modulated by top-down task demands. Reading different types of words requires the division of labor between dorsal and ventral neural pathways, manifested in the difference in the pattern of interplay between phonological and semantic processing. The underlying cognitive processing may determine the activation of reading-related brain regions involved.

Secondly, it further elucidates how underlying processing demands drive the division of labor and collaborative patterns between the dorsal and ventral neural pathways under different levels of orthographic depth. Cross-linguistic differences, mainly influenced by corpus properties and corresponding processing strategies, show neural differences in collaboration patterns between functional reading brain regions. We elaborate on this issue regarding both cross-linguistic comparative and bilingual studies. Evidence from cross-linguistic comparative studies reveals that word reading at different orthographic depths relies on different functional brain region activations, brain region connectivity patterns, and neurophysiological basis. The resulting differences in brain mechanisms for cross-linguistic reading rely on varying degrees of dependence on dorsal and ventral neural pathways. Evidence from bilingual studies suggests that bilinguals selectively rely on either dorsal or ventral neural pathways and the dynamics of connectivity patterns between brain regions, depending on the properties of the corpus, when reading words with different orthographic depths in the two languages. In turn, the similarity of the two languages mastered by bilinguals affects the activation pattern of the reading neural network.

Lastly, it profoundly analyzes how latent processing shapes the dynamic collaboration between neural pathways through the shaping effect of language experience. The shaping effect of reading experience on related brain mechanisms is not only reflected in the influence on the activation sensitivity of brain regions corresponding to reading processing components but also affects the connectivity mechanisms among reading functional brain regions and further shapes the differences in collaboration mechanisms among different neural pathways. In particular, we review the studies to show how reading experience shapes the visual word form area, the form-sound processing area, and their connections with other reading functional brain areas. It also shows how reading experience shapes the dorsal/ventral neural pathway division of labor and cooperation mechanisms.

This review expounds upon the dynamic collaboration mechanism of reading neural pathways driven by processing demands from three distinct perspectives, which not only helps to clarify the internal processing mechanisms of the brain neural network during visual word reading but also provides new evidence for the construction of a universal cognitive and neurophysiological model across languages.

Key words: word reading, model, pathway, dynamics of collaboration