A parallel licensing model of normal slips and phonemic paraphasias

School-Aged Children's Phonological Accuracy in Multisyllabic Words on a Whole-Word Metric

PURPOSE

The purpose of this study is to examine differences in phonological accuracy in multisyllabic words (MSWs) on a whole-word metric, longitudinally and cross-sectionally, for elementary school-aged children with typical development (TD) and with history of protracted phonological development (PPD).

METHOD

Three mismatch subtotals, Lexical influence, Word Structure, and segmental Features (forming a Whole Word total), were evaluated in 3 multivariate analyses: (a) a longitudinal comparison (n = 22), at age 5 and 8 years; (b) a cross-sectional comparison of 8- to 10-year-olds (n = 12 per group) with TD and with history of PPD; and (c) a comparison of the group with history of PPD (n = 12) with a larger 5-year-old group (n = 62).

RESULTS

Significant effect sizes (ηp2) found for mismatch totals were as follows: (a) moderate (Lexical, Structure) and large (Features) between ages 5 and 8 to 10 years, mismatch frequency decreasing developmentally, and (b) large between 8- to 10-year-olds with TD and with history of PPD (Structure, Features; minimal lexical influences), in favor of participants with TD. Mismatch frequencies were equivalent for 8- to 10-year-olds with history of PPD and 5-year-olds with TD. Classification accuracy in original subgroupings was 100% and 91% for 8- to 10-year-olds with TD and with history of PPD, respectively, and 86% for 5-year-olds with TD.

CONCLUSION

Phonological accuracy in MSW production was differentiated for elementary school-aged children with TD and PPD, using a whole-word metric. To assist with the identification of children with ongoing PPD, the metric has the ability to detect weaknesses and track progress in global MSW phonological production.

Lexical and post-lexical phonological representations in spoken production

Theories of spoken word production generally assume a distinction between at least two types of phonological processes and representations: lexical phonological processes that recover relatively arbitrary aspects of word forms from long-term memory and post-lexical phonological processes that specify the predictable aspects of phonological representations. In this work we examine the spoken production of two brain-damaged individuals. We use their differential patterns of accuracy across the tasks of spoken naming and repetition to establish that they suffer from distinct deficits originating fairly selectively within lexical or post-lexical processes. Independent and detailed analyses of their spoken productions reveal contrasting patterns that provide clear support for a distinction between two types of phonological representations: those that lack syllabic and featural information and are sensitive to lexical factors such as lexical frequency and neighborhood density, and those that include syllabic and featural information and are sensitive to detailed properties of phonological structure such as phoneme frequency and syllabic constituency.

A structural account of phonological paraphasias

The aim of this study is to develop a partial theory of phonological paraphasias which has some cross-syndrome and cross-linguistic validity. It is based on the distinction between content and structural units and emphasizes the role of the latter. The notion of structure holds the key to an understanding of the differences among the following three types of data: slips of the tongue, slips of the pen (defined as errors committed by healthy, competent adults), and paraphasias. A comparison of these three data types reveals that slips of the pen and paraphasias display striking similarities whereas slips of the tongue stand apart. This pattern emerges very clearly in an analysis of nine empirical effects all of which are found to be of a structural nature. On the basis of these results, it is argued that both the written output of normals and the oral output of aphasics are generated under a reduced structural representation (i.e., weak activation of structural nodes). However, the reasons for the diminished sensitivity to structure are not the same in the two modalities. While the impoverished structural representation is a likely consequence of the relatively slow production rate in writing, it may stem from an impaired transmission of activation among structural nodes in aphasia. By contrast, the normal speaking process occurs under the sway of a full-fledged structural representation. Hence, slips of the tongue are highly sensitive to structural effects.

Confrontation naming in individuals with temporal lobe epilepsy: a quantitative analysis of paraphasic error subtypes

Although confrontation naming deficits have been observed in dominant temporal lobe epilepsy (DTLE), the relative contribution of impoverished phonologic word retrieval and/or semantic knowledge remains unclear. Analysis of verbal-semantic, phonemic-literal, and combination paraphasias produced during confrontation naming by participants with seizure disorders (52 DTLE; 47 nondominant temporal lobe epilepsy [NDTLE]; 54 psychogenic nonepileptic seizures [PNES]) indicated that the frequency of: (a) verbal-semantic paraphasias was similar across groups, (b) phonemic-literal paraphasias was highest in DTLE, and (c) combination paraphasias was lowest in PNES. Confrontation naming ability was most strongly related to phonemic-literal paraphasia frequency in DTLE and to verbal IQ in both NDTLE and PNES. Greater confrontation naming deficits in DTLE may be attributed to impairments in phonological processing.

Serial control of phonology in speech production: a hierarchical model

A dynamic oscillator-based model of the sequencing of phonemes in speech production (OSCAR) is described. An analysis of phoneme movement errors (anticipations, perseverations, and exchanges) from a large naturalistic speech error corpus provides a new set of data suitable for quantitative modeling and is used to derive a set of constraints that any speech-production model must address. The new computational model is shown to account for error type proportions, movement error distance gradients, the syllable-position effect, and phonological similarity effects. The model provides an alternative to frame-based accounts, serial buffer accounts, and associative chaining theories of serial order processing in speech.

Serial order in phonological encoding: an exploration of the 'word onset effect' using laboratory-induced errors

One controversial phenomenon concerning slips of the tongue is the tendency for the onsets of words to slip more frequently than segments at other word positions. Some researchers attribute this effect to the phonological properties of word onsets, while others suggest it reflects something specific about the role played by the word onset during phonological recovery and/or sequencing. The study reported here examined these two possibilities using a tongue-twister paradigm in which subjects were asked to repeatedly recite a visually-presented word quadruple. The lexical status of the words in target sequences was manipulated independently of their broader phonological characteristics (overall sonority profile and consonant composition) by simply altering their constituent vowels (e.g. case port bed moon vs. koss pait bod marn). Errors elicited on real word targets were found to exhibit a strong word onset effect; this effect was entirely confined to between-word contextual errors. However, nonword targets generated no word onset effect, either overall or on between-word errors considered alone. These findings suggest that the word onset effect cannot be entirely attributed to phonological factors, but instead reflects something about the larger role word onsets play in (real word) speech planning. A new account is offered, which attributes the word onset effect to order-based competition between items at the lexical level.