Assessing Perceptual Difficulty Across Speech Sound Categories and Contrasts to Optimize Minimal Pair Training

Abstract

Purpose: Utilizing psycholinguistic methods, this article aims to ascertain the perceptual difficulty associated with distinguishing between different speech sound categories and individual contrasts within those categories, with the ulti mate goal of informing the use of minimal pair contrasts in perceptual training. Design: Using eye-tracking in the Visual World Paradigm, adults with normal hearing (N = 30) were presented with an auditory word and were required to iden tify the matching image from a selection of four options: the target word, two unrelated words, and a minimal pair competitor contrasting with the target word in word-final position in one of four categories (manner, place, voicing, nasality). Results: We measured fixations to minimal pair competitors over time and found that manner and place competitors exhibited greater competition com pared to voicing and nasality competitors. Notably, within manner competitors, substantial differences in discrimination difficulty were observed among individ ual contrasts. Conclusions: Conventional views of speech sound perception have often grouped sounds into broad categories (manner, place, voicing, nasality), poten tially overlooking the nuanced differences within these groupings, which signifi cantly affect perception. This work is vital for advancing our understanding of speech perception and its mechanisms. Furthermore, this work will help to refine minimal pair treatment strategies in clinical contexts.