Benjamin Munson

The influence of sexual orientation on vowel production (L)

Vowel production in gay, lesbian, bisexual (GLB), and heterosexual speakers was examined. Differences in the acoustic characteristics of vowels were found as a function of sexual orientation. Lesbian and bisexual women produced less fronted /u/ and /ɑ/ than heterosexual women. Gay men produced a more expanded vowel space than heterosexual men. However, the vowels of GLB speakers were not generally shifted toward vowel patterns typical of the opposite sex. These results are inconsistent with the conjecture that innate biological factors have a broadly feminizing influence on the speech of gay men and a broadly masculinizing influence on the speech of lesbian/bisexual women. They are consistent with the idea that innate biological factors influence GLB speech patterns indirectly by causing selective adoption of certain speech patterns characteristic of the opposite sex.

Phonological Knowledge in Typical and Atypical Speech–sound Development

This article discusses 4 types of phonological knowledge: knowledge of the acoustic and perceptual characteristics of speech sounds (perceptual knowledge), knowledge of the articulatory characteristics of speech sounds (articulatory knowledge), higher level knowledge of the ways that words can be divided into sounds and related phonotactic constraints on how sounds can be combined into words (higher level phonological knowledge), and knowledge of the ways that variation in pronunciation can be used to convey social identity (social–indexical knowledge). The first section of the article discusses the nature of these types of knowledge in adults. The second describes how they develop in children with typical language development. The third section outlines how different types of knowledge may be compromised in children with functional speech–sound impairments. Together, these 3 sections serve as a review for practicing clinicians of the types of phonological knowledge that underlie accurate and fluent speech production.

Patterns of phoneme perception errors by listeners with cochlear implants as a function of overall speech perception ability

Many studies have noted great variability in speech perception ability among postlingually deafened adults with cochlear implants. This study examined phoneme misperceptions for 30 cochlear implant listeners using either the Nucleus-22 or Clarion version 1.2 device to examine whether listeners with better overall speech perception differed qualitatively from poorer listeners in their perception of vowel and consonant features. In the first analysis, simple regressions were used to predict the mean percent-correct scores for consonants and vowels for the better group of listeners from those of the poorer group. A strong relationship between the two groups was found for consonant identification, and a weak, nonsignificant relationship was found for vowel identification. In the second analysis, it was found that less information was transmitted for consonant and vowel features to the poorer listeners than to the better listeners; however, the pattern of information transmission was similar across groups. Taken together, results suggest that the performance difference between the two groups is primarily quantitative. The results underscore the importance of examining individuals perception of individual phoneme features when attempting to relate speech perception to other predictor variables.

A method for studying variability in fricatives using dynamic measures of spectral mean

This paper presents a new method for studying within-speaker variability in fricative spectra. In this method, nonlinear regression is used to predict values of the spectral mean of a 10-ms window of frication noise from its position in the fricative. The resulting measure of model fit, R2, is used as an index of within-speaker variability. This method was applied to a corpus of /s/ and /∫/ tokens spoken by three groups of participants: 3–4-year-old children, 7–8-year-old children, and adults. Results indicated that fricatives were more variable when produced before the stop consonant /p/ than before /t/. No difference in variability was noted between adults and children, although a nonsignificant trend of decreased variability in adults was noted.

The sequential cueing effect in children's speech production

This article investigated the development of phonological encoding in speech production by examining the production of reiterant two-word sequences varying in phonological similarity. Two groups of typically developing children and a group of college-aged adults participated. Both groups of children produced target words with longer durations when they were preceded by words sharing initial consonant–vowel (CV) sequences than when preceded by phonologically unrelated words or words sharing vowel–consonant (VC) sequences. For adults, the duration of target words was shorter when they were preceded by words sharing final VC sequences than in the other conditions. The developmental decrease in the influence of CV-related prime words on target-word duration may be related to changes in the level of activation of lexical items during speech production. Developmental changes in the influence of VC-related prime words are less clear, but may be due to age-group specific behavior in the production of identical sequences of words. Children’s early speech production differs considerably from that of adults. Young children possess a limited repertoire of segments and syllable shapes. As a consequence, children’s first words are coarse approximations of the target forms. They typically are characterized by systematic additions, deletions, and substitutions relative to adults’ productions. Throughout the preschool and early elementary school years, these differences decline. Eventually, accurate phoneme production is mastered and children produce words that adults identify as matching the target forms. It is generally thought that this is the point at which a child has acquired the phonology of the ambient language. In contrast, a great deal of evidence suggests that children’s phonologies continue to develop and mature beyond the point when they produce words that match adult targets. Acoustic studies of children’s speech that is perceived to be correct have shown that speech–motor control continues to develop after phoneme accuracy is mastered. A variety of studies have shown that the temporal and spectral characteristics of children’s speech, as well as variability in these measures, continue to develop throughout childhood and adolescence (e.g., Kent & Forner, 1980; Lee, Potamianos, & Narayanan, 1999; Munson, 2004; Nittrouer, 1995; Smith, 1978; Smith, Kenney, & Hussein, 1996). In general, the duration of children’s speech declines throughout childhood. In addition, intraspeaker variability