Duration as a secondary cue in Spanish rhotics

This study investigates language learners’ attention to segmental duration when perceiving the Spanish tap-trill contrast. Previous research has demonstrated that native speakers (NSs), heritage language learners (HLLs), and second language (L2) learners maintain distinct segmental durations when maintaining the tap-trill contrast (e.g., Amengual, 2016; Henriksen, 2015; McCandless, 2020; Willis & Bradley, 2008). In this study, 31 HLLs and 104 L2 learners from a Midwest university listened to five minimal pairs in Spanish with modified closure durations (40 experimental stimuli) ranging from /ɾ/-like (tap-like) (22-40ms) to /r/-like (trill-like) (52ms-85ms). Visual analog sliders were used to connect learners' learner characteristics to continuous perceptions. Results of a regression analysis suggest that both L2 learners and HLLs attend to closure duration when perceiving contrast (β = .009, p < .001), though HLLs demonstrate less categorical overlap than L2 learners. In both groups, linguistic confidence is the strongest predictor of selection certainty for both taps (β = 0.824, p < .001) and trills (β = 1.125, p < .001). The results support a clearer understanding of heritage and developing L2 phonological mapping of the Spanish /ɾ/-/r/ contrast, as well as the utility and limitations of employing continuous measurements in perception research.