The perception of lexical stress in words within a sentence

The acoustic and perceptual correlates of stress in Spanish have been usually studied at the word level, but few investigations have considered them in a wider context. The aim of the present work is to assess the role of fundamental frequency, duration and amplitude in the perception of lexical stress in Spanish when the word is part of a sentence. An experiment has been carried out in which the participants (39 listeners, 20 from Costa Rica and 19 from Spain) had to identify the position of the lexical stress in words presented in isolation and in the same words embedded in sentences. The stimuli in which the position of the stress was not correctly identified have been acoustically analysed to determine the cause of identification errors. Results suggest that the perception of lexical stress in words within a sentence depends on the stress pattern and on the relationship between the values of the acoustic parameters responsible for the prominence of the stressed vowel and those corresponding to the adjacent unstressed vowels.