Stress regularity or consistency? Reading aloud Italian polysyllables with different stress patterns

Stress assignment to three- and four-syllable Italian words is not predictable by rule, but needs lexical look-up. The present study investigated whether stress assignment to low-frequency Italian words is determined by stress regularity, or by the number of words sharing the final phonological segment and the stress pattern (stress neighborhood or consistency). Experiment 1 showed an effect of stress neighborhood: words were read aloud faster and more accurately when they had a prevalence of stress "friends," irrespective of stress regularity. Moreover, when irregularly stressed words have a higher number of stress friends compared to regularly stressed words, they are read even faster (Experiment 2). In Experiment 3, using visual lexical decision, no difference related to the numerosity of stress friends was found. It is concluded that reading aloud Italian low-frequency words with different stress patterns is mainly affected by the numerosity of lexical types that share a given final sequence and the stress pattern. The phonological nature of the numerosity of lexical representations affecting reading aloud finds support in the absence of such effect in visual lexical decision. These results have implications for models of reading aloud that go beyond monosyllables.