Frequency effects in phoneme processing

Abstract

This study tested the hypothesis that phonological segments are activated during word recognition in proportion to their frequency of use, analogous to frequency effects in whole word recognition. Preliminary evidence for the hypothesis was given by Moates, Bond, and Stockmal [LabPhon 7 (2002)] using a word reconstruction task. The present study used a gating task in which progressively longer fragments of a word are presented to listeners who must identify the word after as few gates as possible. High- and low-frequency segments were contrasted by presenting them in word pairs that differed in two segments, e.g., collision–collusion, where /I/ is more frequent than /u/. We constructed 15 words pairs contrasting vowels and 16 pairs contrasting consonants (e.g., relief–release, where /s/ is more frequent than /f/). Identification judgments were gathered from 125 participants. An ANOVA showed high-frequency consonants to be identified at significantly earlier gates than their matched low-frequency consonants with both subjects and items as random factors. No such effect appeared for vowels. Also, whole words containing the high-frequency segments were not identified significantly earlier than those containing low-frequency segments. If the phoneme frequency effect is reliable, then spoken word recognition models should address it.