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R A Koenigsknecht

Publications and source records attributed to R A Koenigsknecht.

9 recordsLinked to original sources
PubMed1976

Development of the voicing contrast: a comparison of voice onset time in stop preception and production.

The acoustic cue voice onset time (VOT) was used to study development of the voicing contrast in 10 two-year-old children, 10 six-year-old children, and 20 adults. Thirty utterances of the words bees, peas, bear, pear, dime, time, goat, and coat were elicited from each subject, VOT measured, and individual production distributions for labial, apical, and velar stops plotted. Significant age-related differences were shown for mean VOT, mean lead time for voiced stops, range of the same words that were examined in the production portion of the investigation were obtained for these subjects from their judgments of synthetic speech stimuli. The relationship between identification and production was examined by assessing the degree of correspondence between the perception and production VOT values. Results of this analysis showed a developmental pattern of change primarily for the voiceless stops in the form of increased correspondence between perceptual identification categories and production VOT values. Three stages for acquisition of the voicing contrast related to VOT are indicated.

Adult↗
PubMed1975

Influence of certain clinical variables on black preschoolers' nonstandard phonological and grammatical performance.

The influence of socioeconomic background, sex, and clinicians' race on the frequency of implementation of nonstandard phonological and grammatical structures was examined in 72 black preschoolers. In order to generalize findings to typical clinical settings, language samples were elicited by 3 black and 3 white clinicians using spontaneous, paragraph completion, and sentence repetition procedures. Results showed that socioeconomic status and sex had a strong effect on black children's usage of nonstandard phonological and grammatical forms. More striking, data suggested that the beginnings of a bidialectal capability were identifiable in the clinical setting in four- and five-year-old black children. Discriminant analysis detailed those nonstandard phonological and grammatical forms which contributed to dialect differences between lower and middle-socioeconomic black children.

Black or African American↗
PubMed1975

Internal consistency of the Northwestern Syntax Screening Test.

This study was designed to evaluate the usefulness of the 40 receptive and 40 expressive items of the Northwestern Syntax Screening Test. Twenty preschoolers with normal language development, 20 preschoolers functioning within the range of normal intelligence diagnosed as language impaired, and 20 mentally retarded children comprised the three subject groups. The subjects were equated for mental age. Stable Hoyt's reliability coefficients indicated that the Northwestern Syntax Screening Test assessed consistently the syntax and morphology used by children with atypical language development. Detailed item analysis revealed the strengths and weaknesses of both receptive and expressive items.

Child↗
PubMed1975

Development of the voicing contrast: perception of stop consonants.

Perceptual development of the voicing contrast was investigated in two-year-old children, six-year-old children, and adults. Subjects were required to identify prevocalic stop consonants from synthetic speech stimuli--bees/peas, bear/pear, dime/time, and goat/coat. The stimuli differed with respect to the acoustic cue, voice onset time (VOT). Identification functions for labial, apical, and velar stops were plotted for each subject. Measurements of 50% crossover, lower and upper limits of the phoneme boundary, and phoneme boundary width were obtained from the identification functions. Significant age-dependent differences in perception of the voicing contrast were observed. The results were interpreted as indicating that the magnitude of VOT difference required for distinguishing between prevocalic stop cognates decreases as a function of the age of the listeners.

Adult↗