Using electrophysiological correlates of early semantic priming to test models of reading aloud

Abstract

The speed at which semantics is accessed by words with consistent (simple) and inconsistent (difficult) spelling–sound correspondences can be used to test predictions of models of reading aloud. Dual-route models that use a word-form lexicon predict consistent words may access semantics before inconsistent words. The Triangle model, alternatively, uses only a semantic system and no lexicons. It predicts inconsistent words may access semantics before consistent words, at least for some readers. We tested this by examining event-related potentials in a semantic priming task using consistent and inconsistent target words with either unrelated/related or unrelated/nonword primes. The unrelated/related primes elicited an early effect of priming on the N1 with consistent words. This result supports dual-route models but not the Triangle model. Correlations between the size of early priming effects between the two prime groups with inconsistent words were also very weak, suggesting early semantic effects with inconsistent words were not predictable by individual differences. Alternatively, there was a moderate strength correlation between the size of the priming effect with consistent and inconsistent words in the related/unrelated prime group on the N400. This offers a possible locus of individual differences in semantic processing that has not been previously reported.

The Use of Neuronal Response Signals as Early Biomarkers of Dyslexia

“…Variations in voltage potential using scalp electrodes are time-locked to recurrent experimental conditions to identify temporal and spatial features of neural responses. Currently, several ERP components (N1/N170, P200 and N400) are well accepted as electrophysiological signatures of language information processing (Friederici et al, 1996;Penke et al, 1997;Perry, 2022). The use of ERP measures in reading research provides investigators information about discrepancies in neuronal activity between typically developing reading children and those diagnosed with dyslexia.…”

Using Monte-Carlo simulation to test predictions about the time-course of semantic and lexical access in reading

“…This means the Triangle model has direct mappings between letters and semantics and thus predicts semantics is accessed very early when reading and that interactions between semantics and phonology should occur. Alternatively, CDP can only predict interactions that occur late in processing [ 11 ] (i.e., after lexical form has been accessed).…”

“…One way that the use of semantic information when reading has been quantified has been to examine the extent to which spelling-sound consistency and semantic variables interact [20,21]. Whilst this is not able to definitively show whether semantics is processed early or late [11,22], interactions are suggestive of a prominent role for semantics in early reading processes, at least when naming tasks are used. The interactions have also been important in helping understand acquired surface dyslexia [23,24].…”