Abstract
Reading is an essential part of contemporary society, yet much is still unknown about the physiological underpinnings of its information processing components. Two influential cognitive models of reading, the connectionist and dual-route cascaded models, offer very different accounts, yet evidence for one or the other remains equivocal. These models differ in several ways, including the role of semantics (word meaning) in mapping spelling to sound. We used a new effective connectivity algorithm, IMaGES, to provide a network-level perspective on these network-level models. Left hemisphere regions of interest were defined based on main effects in functional magnetic resonance imaging and included two regions linked with semantic processing—angular gyrus (AG) and inferior temporal sulcus (ITS)—and two regions linked with phonological processing—posterior superior temporal gyrus (pSTG) and posterior middle temporal gyrus (pMTG). Participants read aloud words of high or low spelling-sound consistency, word frequency, and imageability. Only the connectionist model predicted increased contributions from semantic areas with those computing phonology for low-consistency words. Effective connectivity analyses revealed that areas supporting semantic processing (e.g., the ITS) interacted with phonological areas (e.g., the pSTG), with the pattern changing as a function of word properties. Connectivity from semantic to phonological areas emerged for high- compared to low-imageability words, and a similar pattern emerged for low-consistency words, though only under certain conditions. Analyses of individual differences also showed that variation in the strength of modulation of ITS by AG was associated with reading aloud performance. Overall, these results suggest that connections with semantic processing areas are not only associated with reading aloud, but that these connections are also associated with optimal reading performance.
Highlights
The ability to process written language is fundamental to our capacity to encode and transmit the wealth of human knowledge
Left hemisphere regions of interest were defined based on main effects in functional magnetic resonance imaging and included two regions linked with semantic processing—angular gyrus (AG) and inferior temporal sulcus (ITS)—and two regions linked with phonological processing—posterior superior temporal gyrus and posterior middle temporal gyrus
THE READING NETWORK Graphs of effective connectivity revealed a network of areas with some stable components, such as connections between AG and posterior middle temporal gyrus (pMTG) and between pMTG and posterior superior temporal gyrus (pSTG), and components that varied depending on the nature of the stimuli
Summary
The ability to process written language is fundamental to our capacity to encode and transmit the wealth of human knowledge. According to singleprocess connectionist models (e.g., Seidenberg and McClelland, 1989; Plaut et al, 1996), orthography-phonology (orth-phon) mapping develops according to the frequency of exposure to spelling-sound correspondence patterns This process is mediated by semantics, with the amount of semantic input depending on the nature of the word. Words with consistent spellingsound correspondence patterns (e.g., UST in DUST) can be pronounced without strong activation of semantic (sem) content, whereas words with inconsistent spelling-sound correspondence patterns (e.g., OST in HOST and COST) rely on access to meaning to a greater degree. In this model, semantics is used to reduce interference between inconsistent features of the input
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
