Singleton Consonants Research Articles

Phonologic Error Distributions in the Iowa-Nebraska Articulation Norms Project

The errors on consonant singletons made by children in the Iowa-Nebraska Articulation Norms Project (Smit, Hand, Freilinger, Bernthal, & Bird, 1990) were tabulated by age range and frequency. The prominent error types can usually be described as phonological processes, but there are other common errors as well, especially distortions of liquids and fricatives. Moreover, some of the relevant phonological processes appear to be restricted in the range of consonants or word-positions to which they apply. A metric based on frequency of use is proposed for determining that an error type is or is not atypical. Changes in frequency of error types over the age range are examined to determine if certain atypical error types are likely to be developmental, that is, likely to self-correct as the child matures. Finally, the clinical applications of these data for evaluation and intervention are explored.

Phonetic inventories of 2- and 3-year-old children.

This report provides quasi-longitudinal independent analysis data on two groups of 10 children at 2:0 (years:months), 2:5, 2:9, and 3:3. The analysis included word-initial and word-final phonetic inventories of consonant singletons and clusters and a summary of the relative frequency of seven word shapes. The results indicated that these children were gradually "filling in the gaps" with sounds previously reported to be lacking in slightly younger children.

Phonological Systems of Speech-Disordered Clients with Positive/Negative Histories of Otitis Media

Spontaneous object-naming utterances of two groups of articulation-disordered clients, who were considered to be normal in all areas except speech, were analyzed for phonological error patterns. Subjects with histories of recurrent otitis media during their first 24 months evidenced stridency deletion (in consonant singletons and in consonant clusters) significantly more than did the subjects who had negative otitis media histories. The most prevalent error pattern for both groups pertained to deviations involving /r,/ target phonemes. Limitations of retrospective studies and implications for future research are discussed.

The internal structure of word-initial consonant clusters

The representation of word-initial consonant clusters is explored by examining speech errors that involve a cluster made up of two consonants, such as /pr/ of pray. Spontaneous speech errors and four studies of experimentally induced speech errors yielded similar results. The first member of a cluster is less likely to be lost, added, or mispronounced than the second member of the cluster. In addition, the first member of the cluster is more similar to a singleton consonant than the second member. Simple activation-based explanations cannot account for this data. We argue that clusters must contain two distinct types of syllable positions: a C1 position (also found with singleton consonants) and a C2 position (found only in clusters).

Context effects in Japanese perception of English /r/ and /I/

Perception of English /r/ and /l/ is a well‐known difficulty for Japanese learning English. An identification test for minimal pairs read by two American speakers was administered to 32 Japanese students of English, first just after arrival in the United States, and then nine weeks later at the completion of an intensive English program emphasizing oral skills. Little improvement was observed after oral training. The perception of /r/ and /l/ as singletons and in consonant clusters exhibited quite opposite trends. In clusters, /l/ was perceived more accurately than /r/ (66% versus 52%), while for singletons, /l/ was somewhat worse than /r/ (64% versus 70%). Singleton consonants in word‐final position were more accurately perceived than initial singletons (77% versus 57%) while for clusters, the finals were slightly worse than initials (56% versus 62%). Thus both the /r‐l/ effect and word‐position effect interact with the singleton‐cluster factor but not with each other. These findings will be discussed in relation to the phonotactics of both Japanese and English and in terms of their acoustic correlates. [Supported by NIH, HD12511.]

Apraxia of speech in patients with Broca's aphasia: A study of phoneme production accuracy and error patterns

Phonetic analyses were made of the articulatory errors of ten Broca's aphasics with apraxia of speech. Presentation mode, phoneme position, and phoneme frequency-of-occurrence were related to phoneme difficulty. Consonant clusters were more difficult than consonant singletons; vowels were easiest. Substitution, addition, and compound errors predominated, while distortions and omissions were much less frequent. A subphonemic feature analysis of substitution and distortion errors showed a majority of errors to be close approximations to target phonemes.