Perceptual sensitivity to stress in native English speakers learning Spanish as a second language

Second language (L2) learners of Spanish whose first language (L1) is English tend to find Spanish lexical stress patterns difficult to acquire. This study investigates whether such difficulty derives, at least in part, from an obstacle encountered during perceptual processing: reduced perceptual sensitivity to stress distinctions. Participants were adult L1 English L2 Spanish learners of various proficiency levels. The experiment was a categorical matching task with triads of auditory stimuli minimally contrasting in stress (target) or segmental composition (baseline), an ABX task. The results show that learners were more accurate in the baseline condition than in the target condition, suggesting reduced perceptual sensitivity to stress relative to other contrasts. The reduction in accuracy, however, was restricted to trials in which matching items were not adjacent, further suggesting an obstacle with phonological processing in working memory rather than perceptual categorization. The default stress processing routines of L1 English L2 Spanish learners, optimized for their L1 (not their L2), may be responsible for their acquisitional obstacles with this feature of the Spanish language.