Parallel word reading revealed by fixation-related brain potentials

Abstract

During reading, the brain is confronted with many relevant objects at once. But does lexical processing occur for multiple words simultaneously? Cognitive science has yet to answer this prominent question. Recently it has been argued that the issue warrants supplementing the field's traditional toolbox (response times, eye-tracking) with neuroscientific techniques (EEG, fMRI). Indeed, according to the OB1-reader model, upcoming words need not impact oculomotor behavior per se, but parallel processing of these words must nonetheless be reflected in neural activity. Here we combined eye-tracking with EEG, time-locking the neural window of interest to the fixation on target words in sentence reading. During these fixations, we manipulated the identity of the subsequent word so that it posed either a syntactically legal or illegal continuation of the sentence. In line with previous research, oculomotor measures were unaffected. Yet, syntax impacted brain potentials as early as 100 ms after the target fixation onset. Given the EEG literature on syntax processing, the presently observed timings suggest parallel word reading. We reckon that parallel word processing typifies reading, and that OB1-reader offers a good platform for theorizing about the reading brain.