A methodological study of factors affecting the judgment of misarticulated /s/.

Two studies involving judgments of /s/ misarticulation are described. The first involved simultaneous audio and video recordings of three clinically different /s/ misarticulating children. Their recorded /s/ productions, embedded in 54 sentences with varying phonetic contexts, were judged on an acceptable/unacceptable/questionable basis. There was a large proportion of judgments in the questionable category, relatively low interjudge reliability, and few clear enhancing contexts. To better define the problems inherent in using recorded /s/ misarticulations, a second study was undertaken in which six specially chosen /s/ defective and eight normally speaking subjects spoke a set of 12 sentences containing a total of 24 /s/ target words. These productions were judged dichotomously as correct/incorrect under live conditions and from tape recorded conditions. Both normal and /s/ defectives were easily and reliably detected under live speaking conditions; judgments from tape recordings showed a reduction in reliability of judgment and reduced ability to detect the /s/ defective speakers' errors. Examination of the recorded /s/ defective productions revealed that certain phonetic contexts, especially adjacent apical stops, appeared to encourage judgments of correct /s/ productions. Thd discussion includes suggestion concerning techniques for sampling and judging /s/ misarticulations.

Children's identification of their own /s/ misarticulations.

Six /s/ misarticulating children, two normal-articulating children, and four adults identified a variety of /s/ productions as normal and defective. The /s/ samples were embedded in short segments of speech spliced from the sentence repetitions of the same eight children. Results indicate that each misarticulator could identify at least some of his or her own productions as defective. Although no statistically significant differences appeared between groups, the two lateralizing subjects exhibited poorer identification scores on defective /s/ items than did the other groups, possibly indicating somewhat poorer auditory monitoring abilities. Included is a discussion of procedural considerations important to research of this type.

An acoustic-articulatory description of children's defective /s/ productions.

The /s/ production of six /s/-defective children and two normal controls were subjected to spectrographic analysis. Articulatorily, two of the children were dentalizers, two had lateral emission of friction, and two were of an "other" type. Results show for normals an /s/ spectrum which is compact (5-11 kHz), powerful, and dominated by strong, sharp spectral peaks at 6 and 10 kHz. Their spectra were context sensitive. Dental subjects showed flatter, less peaked, higher frequency (6-12 kHz), and less intense noise spectrum, which was not so context sensitive. Lateral /s/ subjects showed a broad 4-9 or 4-10 kHz spectrum characterized by somewhat smaller, more numerous peaks, and a lower cutoff frequency (about 4kHz) than for normals. The "other /s/ defectives varied very widely, so that no consistent pattern emerged. The acoustic data are then discussed in terms of the articulation of varieties of friction noise.

Mandibular position during children's defective /s/ productions.

Mandibular displacement during /s/ production was monitored via a mercury strain gauge which was taped to the face of two normally articulating and six /s/-misarticulating children. Simultaneous audio and jaw displacement visicorder traces were produced from an FM-tape recording of each experimental session, and were subsequently analyzed. Results indicated that various /s/-misarticulating subgroups exhibit different mandibular positions during /s/-production, and phonetic contextual effects upon mandibular position also vary by articulatory type.

Elicited imitation of selected features of two american English dialects in Head Start children.

Three measures were used to check the bidialectal imitative facility of 100 black, white, and Spanish-speaking Head Start children. In general, blacks and Spanish-speaking subjects performed more accurately on black English markers than on Standard English markers and whites, the reverse. When the children did make an error on the feature marker they usually substituted the opposing dialectal marker. Blacks and Spanish-speaking subjects were more apt to be accurate on the total sentence when it was given in black English. Several explanations are offered for group similarities and differences.

Performance of children with normal and impaired oral language production on a set of auditory comprehension tests.

The purpose of this study was to investigate the comprehension abilities of children with impaired expressive language and to obtain information on the interrelationships among tests of comprehension. Forty preschool children, 20 with normal language and 20 with impaired expressive language, were given a set of auditory comprehension tests. As a group, the language-impaired children demonstrated deficits in comprehension when compared to the normal-language children. However, both groups scored near the ceiling on several tests, and on most tests that did differentiate the two groups, the mean scores of both groups when applied to performances of middle-class white children. An analysis of responses to selected groupings of analogous items revealed that a preschool child's correct response to a linguistic stimulus in one instance provides no assurance that the child will respond similarly to the stimulus in another linguistic environment with different task demands and different foil alternatives. In addition, the large majority of correlations among the test were nonsignificant, indicating that it is not clinically appropriate to regard these measures of language comprehension as equivalent.

Sentence repetition in preschoolers: effects of length, complexity, and word familiarity.

Seventy-two sentences presented to ten preschool children for repetition were designed so that three sentence construction factors varied independently. The factors were (1) length in number of words, (2) complexity of personal pronouns and main verbs as scaled by Lee (1974), and (3) word familiarity, defined as common vocabulary or the substitution of a nonsense word in place of a typical noun or verb in the model sentence. Three methods were employed for scoring the children's responses: (1) number of retained words, (2) Developmental Sentence Scoring (Lee, 1974), and (3) Stephens's Categories (Stephens, 1974). Eighteen sentences were re-presented for the assessment of reliability. The results of multiple regression analyses indicated that length was the important contributing factor in the children's responses to the model sentences and that Stephens's Category Scale of response scoring was the most sensitive method for detecting the influence of the three sentence factors on the children's responses.