Jessica A. Barlow

Age-related changes in acoustic characteristics of adult speech

UNLABELLED This paper addresses effects of age and sex on certain acoustic properties of speech, given conflicting findings on such effects reported in prior research. The speech of 27 younger adults (15 women, 12 men; mean age 25.5 years) and 59 older adults (32 women, 27 men; mean age 75.2 years) was evaluated for identification of differences for sex and age group across measures of fundamental and formant frequencies (F0, F1, F2 and F3) and voice onset time (VOT). There were significant sex-by-age group interactions for F0, F1, and VOT, some of which were specific to individual speech sounds. The findings suggest that further research on aging speech should focus on sex differences and the potential influence such changes may have on communication abilities of older adults with hearing loss. LEARNING OUTCOMES The reader will be able to understand and describe (1) possible changes in specific acoustic properties with age, (2) how these changes may differ for women and men, and (3) the potential impact these changes may have on the speech understanding of older individuals with hearing loss.

Constraint Conflict in Cluster Reduction

When children reduce onset clusters to singletons, a common pattern is for the least sonorous member of the adult cluster to be produced. Within optimality theory (Prince & Smolensky, 1993), this pattern has been accounted for in terms of a fixed ranking of onset constraints that evaluate a segments degree of sonority, whereby onset glides violate the highest ranked constraint, and onset stops the lowest. Not all children follow the sonority pattern, however. In this paper, we apply two fundamental principles of optimality theory to yield predictions about other childrens cluster reduction patterns. The first principle is that of factorial typology, according to which all rankings of constraints should yield possible languages. To produce the sonority pattern, all conflicting constraints must rank beneath the onset sonority constraints. If they rank above the onset sonority constraints, these other constraints will force deviations from the sonority pattern. In this paper, we show how divergences from the sonority pattern are caused by three well-motivated conflicting constraints: *Fricative, *Dorsal, and Max-Labial. This is documented in the speech of two normally developing children (about 1;6-2;3) and a child with a phonological delay (3;8). The second principle we appeal to is that of emergent constraint activity, according to which the effects of violated constraints can be observed when higher ranked conflicting constraints are not at issue. We show that even when the onset sonority constraints are outranked by the conflicting constraints, under the right circumstances the sonority pattern does emerge in the forms produced by these children.

Interaction in bilingual phonological acquisition: evidence from phonetic inventories

Abstract Purpose. To examine how interaction contributes to phonological acquisition in bilingual children in order to determine what constitutes typical development of bilingual speech sound inventories. Method. Twenty-four children, ages 3–4, were included: eight bilingual Spanish–English-speaking children, eight monolingual Spanish speakers, and eight monolingual English speakers. Single word samples were obtained to derive phonetic inventories. After Dinnsen, Chin, Elbert and Powell for English and Cataño, Barlow, and Moyna for Spanish, the childrens inventories were assigned to one of five levels of complexity. Levels were compared for similarities and differences within bilinguals and between monolinguals and bilinguals. Inventories were examined for evidence of interaction in the form of phonological transfer. Results. Bilinguals had phonetic inventories that were commensurate in complexity with monolinguals. Bilingual children acquire two inventories in the same amount of time that monolinguals acquire one, and with the same level of complexity. Evidence of transfer occurred from English to Spanish and vice versa. Implications. These findings are useful for the differentiation of language difference from disorder and aid in avoiding underdiagnosis of speech sound disorders. Although bilingual children maintain separation of phonological structures, a low level of interaction between their two languages exists.

The Structure of/s/-Sequences: Evidence from a Disordered System.

This study considers the much-debated markedness and structural status of word-initial /s/-sequences in English by examining the development of KR (male, age 3;6) who has a phonological disorder. Three points in time are discussed: (1) when all initial consonant sequences are reduced to singletons; (2) when only initial /s/-sequences surface correctly; and (3) when all initial consonant sequences surface correctly. While these production patterns are common across developing systems, few accounts have addressed them in terms of structure or markedness. Toward that end, it is argued that KRs /s/-sequences surface as adjuncts, rather than complex onsets. This is explained within optimality theory, whereby high-ranking markedness constraints prevent complex onsets but not adjuncts. The account offers an explanation for consonant sequence asymmetries within and across grammars, allowing for differing representations for /s/-sequences across speakers and for variation exhibited in childrens productions. A typology of possible grammars is therefore offered, and clinical implications are considered.

On the characterization of a chain shift in normal and delayed phonological acquisition

Several theoretical and descriptive challenges are presented by childrens phonological substitution errors which interact to yield the effect of a chain shift. Drawing on an archival study of the sound systems of five children (ages 3;5 to 4;0) with normal development and 47 children (ages 3;4 to 6;8) with phonological delay, one such chain shift, namely the replacement of target /theta/ by [f] and the replacement of /s/ by [theta], was identified in the speech of six children from the two subgroups. Different derivational and constraint-based accounts of the chain shift were formulated and evaluated against the facts of change and the childrens presumed perceptual abilities. An adequate account in either framework was found to require the postulation of underspecified and, in some instances, nonadult-like underlying representations. Such representations were able to reconcile within a single-lexicon model the presumed production/perception dilemma commonly associated with acquisition. Continuity was also preserved by limiting underlying change to just those lexical items which exhibited a change phonetically.

Phonological change and the representation of consonant clusters in Spanish: A case study

This single‐subject case study evaluates effects of treatment of a complex onset on the sound system of a monolingual Spanish‐speaking child (female, aged 3;9) with phonological delay. Pretreatment, the child excluded all consonant+liquid clusters, as well as tap /ɾ/ and trill /r/. Immediately following training on /fɾ‐/ in non‐words, the child generalized across consonant+liquid clusters and the tap singleton. These improvements continued to 2 months post‐treatment follow‐up, with the ultimate addition of the trill at that point in time. Consonant+glide sequences, whose structural status as complex onsets is debated in the Spanish phonology literature, patterned differently from consonant+liquid sequences. Specific findings are viewed in light of linguistic markedness, syllable structure, sonority sequencing, and the representation of consonant clusters.

Individual differences in the production of initial consonant sequences in Pig Latin

Accounts of English initial consonant sequences suggest that not all sequences are the same. Data from acquisition, speech errors and language games necessitate unusual rules/constraints on subsyllabic structure to account for C/j/ and /s/C(C) sequences. Acquisition evidence supports within- and across-speaker representational differences for these sequences; however, such evidence for adults remains elusive. This study investigates the representation of consonant sequences within and across adult speakers of English. Thirty adults were trained in Pig Latin using words with singletons and true clusters. Generalization to C/j/ and /s/C(C) was then measured. Results suggested differential patterning for consonant sequences within and across speakers based on consistent production patterns and errors. Differences occurred most often with /s/C(C) sequences and even more so for C/j/. Orthography also influenced production patterns. Results support differential representational structure within and across individual grammars, which is accounted for via constraint-based output-output correspondence between surface and Pig Latin forms.

A Retrospective Study of Phonetic Inventory Complexity in Acquisition of Spanish: Implications for Phonological Universals.

This study evaluates 39 different phonetic inventories of 16 Spanish‐speaking children (ages 0;11 to 5;1) in terms of hierarchical complexity. Phonetic featural differences are considered in order to evaluate the proposed implicational hierarchy of Dinnsen et al.s phonetic inventory typology for English. The childrens phonetic inventories are examined independently and in relation to one another. Five hierarchical complexity levels are proposed, similar to those of English and other languages, although with some language‐specific differences. These findings have implications for theoretical assumptions about the universality of phonetic inventory development, and for remediation of Spanish‐speaking children with phonological impairments.

Acquisition of #sC clusters in Spanish-English bilingual children

We evaluate productions of word-initial /s/ clusters (#sC clusters) in English by 40 Spanish-English bilingual children (aged 2;11 – 4;5). These clusters have been studied considerably in research on the phonology of English and related languages because of their unusual patterning. Specifically, #sC clusters violate several phonotactic and/or universal constraints on syllable structure. Monolingual English-speaking children also show production patterns for these clusters that are quite different from those of other clusters. Yet to be fully explored, however, is how these clusters pattern in the speech of English-speaking children who also speak another language that prohibits #sC clusters, such as Spanish. We evaluate Spanish-English bilingual childrens productions of #sC clusters to compare their production patterns with the findings of previous research. Results generally indicate that these childrens production patterns are consistent with cross-linguistic predictions related to sonority and sonority sequencing. Additionally, some childrens productions appeared to be influenced by Spanish phonotactics.

Age of acquisition and allophony in Spanish-English bilinguals.

This study examines age of acquisition (AoA) in Spanish-English bilinguals’ phonetic and phonological knowledge of /l/ in English and Spanish. In English, the lateral approximant /l/ varies in darkness by context [based on the second formant (F2) and the difference between F2 and the first formant (F1)], but the Spanish /l/ does not. Further, English /l/ is overall darker than Spanish /l/. Thirty-eight college-aged adults participated: 11 Early Spanish-English bilinguals who learned English before the age of 5 years, 14 Late Spanish-English bilinguals who learned English after the age of 6 years, and 13 English monolinguals. Participants’ /l/ productions were acoustically analyzed by language and context. The results revealed a Spanish-to-English phonetic influence on /l/ productions for both Early and Late bilinguals, as well as an English-to-Spanish phonological influence on the patterning of /l/ for the Late Bilinguals. These findings are discussed in terms of the Speech Learning Model and the effect of AoA on the interaction between a bilingual speaker’s two languages.