EXPRESS: The role of orthographic cues to stress in Italian visual word recognition

In the present study stress diacritics were used to investigate the processing of stress information in lexical decision. We ran two experiments in Italian, a language in which stress position is not predictable by rule and only final stress – i.e., the less common pattern – is orthographically marked with a diacritic. In Experiment 1, a lexical decision task, two factors were manipulated: The stress pattern of words – antepenultimate (non dominant) and penultimate (dominant) – and the presence/absence of the diacritics, signalling the stress position. Participants were faster to categorize stimuli as words when they bear dominant than non dominant stress. However, the advantage disappeared when the diacritic was used. In Experiment 2, a same-different verification task was used in which participants had to decide if a referent word and a target were same (carota-CAROTA, /ka'rɔta/; tavolo-TAVOLO, /'tavolo/) or different. We compared two conditions requiring a "different" response, in which referent and target with dominant and non dominant stress were congruent (caròta-CAROTA; tàvolo-TAVOLO) or incongruent (càrota-CAROTA; tavòlo-TAVOLO) with the word’s stress. For words with dominant stress, “different” responses were faster in the incongruent condition than the congruent condition. This congruency effect was not observed for words with non-dominant stress pattern. Overall, the data suggest that stress information is based on lexical phonology, and the stress dominance effect has a lexical base in word recognition.