Can cognitive models explain brain activation during word and pseudoword reading? A meta-analysis of 36 neuroimaging studies.

Abstract

Reading in many alphabetic writing systems depends on both item-specific knowledge used to read irregular words (sew, yacht) and generative spelling-sound knowledge used to read pseudowords (tew, yash). Research into the neural basis of these abilities has been directed largely by cognitive accounts proposed by the dual-route cascaded and triangle models of reading. We develop a framework that enables predictions for neural activity to be derived from cognitive models of reading using 2 principles: (a) the extent to which a model component or brain region is engaged by a stimulus and (b) how much effort is exerted in processing that stimulus. To evaluate the derived predictions, we conducted a meta-analysis of 36 neuroimaging studies of reading using the quantitative activation likelihood estimation technique. Reliable clusters of activity are localized during word versus pseudoword and irregular versus regular word reading and demonstrate a great deal of convergence between the functional organization of the reading system put forward by cognitive models and the neural systems activated during reading tasks. Specifically, left-hemisphere activation clusters are revealed reflecting orthographic analysis (occipitotemporal cortex), lexical and/or semantic processing (anterior fusiform, middle temporal gyrus), spelling-sound conversion (inferior parietal cortex), and phonological output resolution (inferior frontal gyrus). Our framework and results establish that cognitive models of reading are relevant for interpreting neuroimaging studies and that neuroscientific studies can provide data relevant for advancing cognitive models. This article thus provides a firm empirical foundation from which to improve integration between cognitive and neural accounts of the reading process.

How Word Meaning Influences Word Reading

“…The evidence shows that they are, even during tasks that do not require meaning to be accessed, such as reading aloud/silently and lexical decision (judging whether a letter string is a word). Relative to reading pseudowords (pronounceable but meaningless letter strings), reading words activates brain regions such as left angular and middle temporal gyri, which are likely involved in semantic processing (Taylor, Rastle, & Davis, 2013;Taylor et al, 2014a). Furthermore, neurophysiological experiments reveal that this differential response to meaningful versus meaningless items can occur as early as 160-200ms post-stimulus onset (Carreiras, Armstrong, Perea, & Frost, 2014).…”

“…In both a meta-analysis and an empirical study, Taylor et al (2013;2014a) found that exception words activate left inferior frontal gyrus more than regular words. This may reflect the retrieval and selection of semantic knowledge (Graves, Desai, Humphries, Seidenberg, & Binder 2010), or selection between the multiple pronunciations that are possible for exception words (Taylor et al, 2013;2014a).…”

“…The evidence shows that they are, even during tasks that do not require meaning to be accessed, such as reading aloud/silently and lexical decision (judging whether a letter string is a word). Relative to reading pseudowords In both a meta-analysis and an empirical study, Taylor et al (2013;2014a) Semantic dementia patients are more likely to correctly read an exception word aloud if they still know the meaning of that word (Graham, Hodges, & Patterson, 1994), mirroring results in the developmental literature (Ricketts et al, 2007). Large scale studies of semantic dementia have shown a strong link between the degree of the exception word reading deficit and the severity of semantic impairment on tasks that do not require reading (e.g., picture naming, spoken word-to-picture matching; Woollams et al, 2007).…”

A meta‐analysis of functional magnetic resonance imaging studies of eye movements and visual word reading

“…There has been a large body of research using meta‐analytical approaches in the field of single‐word recognition (Jobard, Crivello, & Tzourio‐Mazoyer, 2003; Martin, Schurz, Kronbichler, & Richlan, 2015; Taylor, Rastle, & Davis, 2013; Turkeltaub, Eden, Jones, & Zeffiro, 2002). In general, our results were in agreement with previous findings that ventral regions, such as the VOT, MTG, and IFG, are activated during single word processing.…”

“…It is noted that these meta‐analysis studies included orthographic, phonological, and semantic tasks for single word recognition and contained both silent and oral reading. Consequently, researchers have also found “dual routes” for single word reading (e.g., Coltheart, Rastle, Perry, Langdon, & Ziegler, 2001; Jobard et al., 2003; Taylor et al., 2013). This dual‐route system is comprised of a dorsal phonological pathway (i.e., the STG, SMG, and opercular part of the IFG) and a ventral lexical‐semantic pathway (i.e., the VOT, MTG, and triangular part of the IFG) among left perisylvian regions.…”