Biomedical subjects

Harvey M Sussman

Publications and source records attributed to Harvey M Sussman.

4 recordsLinked to original sources

PubMed2005

An investigation of speech perception in children with specific language impairment on a continuum of formant transition duration.

Fifteen children diagnosed with specific language impairment (SLI) and 15 typically developing (TD) children were tested for identification performance on 2 synthetic speech continua varying in formant transition durations (FTDs). One continuum varied from /ba/ to /wa/, and the other varied from /da/ to /ja/. Various d'-related measures from signal detection theory were used to compare category boundaries and indirectly derive sensitivity to phonetic changes in category tokens along each continuum. The SLI group showed less consistent identification performance along the /ba/-/wa/ series relative to the TD group, as well as reduced sensitivity to phonetic changes along the continuum. On the /da/-/ja/ series, the SLI group revealed less consistent identification performance on the short FTD end but similar identification levels to the TD group at the long FTD end. The overall results support the contention that children with SLI reveal a deficiency in the processing of speech sounds at the level of segmental identity.

Child↗

PubMed2002

Representation of phonological categories: a functional role for auditory columns.

A speculative model for representing phonological categories for stop place of articulation is offered. The model is analogous to neural columns in both inferotemporal cortex in the macaque for achieving constancy in object recognition and in the inferior colliculus of the barn owl for resolving ambiguous phase disparities for sound localization. Hypothetical auditory columns for encoding the vowel context-induced variability of F2 transitions are described using acoustic data from locus equation scatterplots of human speech. Such analyses serve to absorb the allophonic variability inherent in coarticulated speech utterances.

Animals↗

PubMedDate not supplied

The integrity of the syllable in developmental apraxia of speech.

UNLABELLED: Three children with developmental apraxia of speech (DAS) identified the number of syllables in words, judged intrasyllabic sound positions, and constructed syllable shapes within monosyllabic frames. Results suggest that DAS children demonstrate an apparent breakdown in the ability to perceive "syllableness" and to access and compare syllable representations with regard to position and structure. Based on these findings, DAS is viewed as a disorder characterized by an impoverished phonological representation system. LEARNING OUTCOMES: On the basis of this article, the reader will be able to (1) describe the deficits in syllabic perception demonstrated by some participants with DAS; (2) examine the utility of metalinguistic tasks in the differential diagnosis of DAS; and (3) evaluate the findings with respect to competing theoretical perspectives on DAS.

Apraxias↗

PubMedDate not supplied

The trough effect: implications for speech motor programming.

While the existence of the trough effect is unquestioned, its theoretical significance is unknown. A multifaceted instrumental approach - spectrographic, cineradiographic, and vocal tract modeling - was used to document the trough effect in open (V.CV) and closed (VC.V) syllable forms using a symmetrical vowel context surrounding labial stops. Collectively, the results document the trough phenomenon as a momentary deactivation of tongue and/or lip movement after V1 and continuing into the stop closure. This empirical event suggests a segment-by-segment activation pattern as opposed to a diphthongal vowel-to-vowel trajectory with an independent and superimposed consonantal gesture. Quantitative models of VCV coarticulation must incorporate the trough effect in order to more effectively capture the kinematic properties of speech.

Humans↗