Orthographic familiarity of word N affects attentional disengagement from word N-1 in reading

The effect of the load of word N on attentional disengagement from word N-1 during reading was investigated using a dual task (adapted from Fischer, 1999; see Ghahghaei, Linnell, Fischer, Dubey, & Davis, in press). Participants were presented on each trial with a single sentence. Each sentence contained a critical word, word N, with its load manipulated at two levels of orthographic familiarity (high/low) and printed frequency (high/low). Participants (eighteen monolingual English-speakers with normal vision and reading ability) were asked to (i) read the sentence for comprehension, and (ii) make an unspeeded 2-AFC discrimination about a gaze-contingent probe. Probes were briefly (for 30 ms) superimposed on a single character at the gaze location on word N-1 after a random delay (180ms to 250 ms) from the beginning of the first fixation on word N-1. Reading was monocular and the dominant eye was recorded using a EyeLink2 eye-tracker. Each participant read 360 sentences (90 sentences for each combination of orthographic familiarity and frequency). Trials were included in the analysis if there was only one single fixation on word N-1. A two-way repeated-measures ANOVA on probe-discrimination accuracy showed an effect of the orthographic familiarity of the first trigram of word N on probe discrimination at word N-1 (p=0.01): average error for low-orthography words was 25.8 % (SEM=2.3) and for high was 18.6 % (SEM=2.5). Our result suggests that the orthographic familiarity of the first trigram of word N (a) is analysed before the word is fixated (White, Liversedge, 2006) and (b) affects the strength of attentional disengagement from word N-1.