Journal of speech and hearing research最新文献

Ninety-six adults with normal hearing viewed three types of recorded speechreading materials (consonant-vowel nonsense syllables, isolated words, and sentences) on 2 days. Responses to nonsense syllables were scored for syllables correct and syllable groups correct; responses to words and sentences were scored in terms of words correct, phonemes correct, and an estimate of visual distance between the stimulus and the response. Generalizability analysis was used to quantify sources of variability in performance. Subjects and test items were important sources of variability for all three types of materials; effects of talker and day of testing varied but were comparatively small. For each type of material, alternative models of test construction and test-score interpretation were evaluated through estimation of generalizability coefficients as a function of test length. Performance on nonsense syllables correlated about .50 with both word and sentence measures, whereas correlations between words and sentences typically exceeded .80.

This study investigated the effects of normal aging and Alzheimer's disease on listeners' ability to recognize gated spoken words. Groups of healthy young adults, healthy older adults, and adults with Alzheimer's disease were presented isolated gated spoken words. Theoretical predictions of the Cohort model of spoken word recognition (Marslen-Wilson, 1984) were tested, employing both between-group and within-group comparisons. The findings for the young adults supported the Cohort model's predictions. The findings for the older adult groups revealed different effects for age and disease. These results are interpreted in relation to the theoretical predictions, the findings of previous gating studies, and differentiating age from disease-related changes in spoken word recognition.

It has been shown that people who stutter can speak with greatly reduced stuttering after treatments that use variations of Goldiamond's (1965) prolonged-speech (PS). However, outcome research to date has not taken account of several important issues. In particular, speech outcome measures in that research have been insufficient to show that lasting relief from stuttering has been achieved by clients outside the clinic for meaningful periods. The present study used extensive speech outcome measures across a variety of situations in evaluating the outcome of an intensive PS treatment (Ingham, 1987). The speech of 12 clients in this treatment was assessed on three occasions prior to treatment and frequently-on eight occasions-after discharge from the residential setting. For 7 clients, a further assessment occurred at 3 years posttreatment. Concurrent dependent measures were percent syllables stuttered, syllables per minute, and speech naturalness. The dependent measures were collected in many speaking situations within and beyond the clinic. Dependent measures were based on speech samples of substantive duration, and covert assessments were included in the study. Detailed data were presented for individual subjects. Results showed that 12 subjects who remained with the entire 2-3-year program achieved zero or near-zero stuttering. The majority of subjects did not show a regression trend in %SS or speech naturalness scores during the posttreatment period, either within or beyond the clinic. Some subjects showed higher posttreatment %SS scores during covert assessment than during overt assessment. Results also showed that stuttering was eliminated without using unusually slow and unnatural speech patterns. This treatment program does not specify a target speech rate range, and many clients maintained stutter-free speech using speech rates that were higher than the range typically specified in intensive PS programs. A significant correlation was found between speech rate and perceived posttreatment speech naturalness.

A 2-year follow-up of the mathematical abilities of young children with specific language impairment (SLI) is reported. To detect the nature of the difficulties children with SLI exhibited in mathematics, the first- and second-grade children's performance was compared to mental age and language age comparison groups of typically developing children on a series of tasks that examined conceptual, procedural, and declarative knowledge of mathematics. Despite displaying knowledge of many conceptual aspects of mathematics such as counting plates of cookies to decide which plate had "more," children with SLI displayed marked difficulty with declarative mathematical knowledge that required an immediate response such as rote counting to fifty, counting by 10's, reciting numerals backwards from 20, and addition facts such as 2 + 2 =?. Moreover, children with SLI performed similarly to their cognitive peers on mathematical tasks that allowed children to use actual objects to count and on math problems that did not require them to exceed the sequence of numbers that they knew well. These findings offer further evidence that storage and/or retrieval of rote sequential material is particularly cumbersome for children with SLI.

The performance of 32 children with language impairment-11 with expressive language impairment only (LI-E subgroup) and 21 with both receptive and expressive language impairment (LI-ER subgroup)-and of 22 children without language impairment (LN subgroup) was examined in a study of perception and imitation of synthesized /ba/ and /da/ syllables. Formant transition duration and task difficulty were varied in the perceptual tasks. The LI-E children were able to identify the syllables as well as the LN; the LI-ER were not. Of the children who succeeded on an identification task and proceeded to a serial ordering task incorporating the same stimuli, the LI-E children were the least successful on the second task. The ability to label the stimuli perceptually was highly correlated with absence of speech articulation errors in the LI children and with performance on the imitation task in all subjects. The findings are examined in relation to the hypotheses that rapid-rate perceptual processing is the sole basis of language impairment in children and that, in these children, production skill may predict phoneme perception rather than the reverse.

This study had two specific aims. The first aim was to investigate whether, during a silent reading task, persons who stutter encode phonological and semantic information move slowly then persons who do not stutter. The second aim was to investigate how the syntactic context of stimulus sentences influences the speed of coding. Fourteen adult persons who stutter and 14 adult persons who do not stutter participated in a self-paced word-by-word reading experiment. While reading a prose text silently, participants monitored target words that were specified before the presentation of the text. The target words to be monitored for were phonologically similar, categorically related, or identical to a cue word. The influence of syntactic information on the word-monitoring reaction time was studied by presenting the text either as normal prose, in a syntactically correct but semantically anomalous version, or in random word order. The results suggest that the two groups are not different with respect to the speed of word identification but that persons who stutter retrieve semantic information more slowly than persons who do not stutter.

A new device for the stimulation of intraoral tissues in human neonates is described. This instrument, known as an actifier, features a wide frequency range for mechanical stimulation, integrated multichannel electomyographic electrode pairs, and the capacity for transducing law compression during non-nutritive sucking behavior. The stimulus/recording interface consists of a modified pacifier. The actifier has been used to investigate the responsiveness of the sucking central pattern generator in human infants to mechanical perturbation.

Audibility thresholds for a 1000-Hz sinusoid were measured with a standard clinical (CLIN) procedure and a two-interval, forced-choice (2IFC) adaptive procedure bracketing 79% correct. Both used 2- and 5-dB step sizes in quiet and in a continuous, broadband noise background. Clinical thresholds were from 2 to 4 dB higher than 2IFC thresholds, depending on the condition. Step size had a larger effect on the CLIN thresholds than the 2IFC thresholds. For the CLIN procedure, thresholds with a 2-dB step size were 1.4 dB lower than with a 5-dB step size. For the 2IFC procedure, thresholds with a 2-dB step size were 0.8 dB higher than with a 5-dB step size. Reliability, as measured by the intrasubject standard deviation, was better for the 2IFC than for the CLIN procedure and better in noise than in quiet. Reliability was unaffected by step size. Adding extra trials to the 2IFC adaptive track decreased the variability across threshold estimates, but more for the noise background than the quiet background. The efficiency of the 2IFC procedure was fairly constant across track length in noise, but decreased for longer track lengths in quiet. In both quiet and noise backgrounds, CLIN procedures were much more efficient than 2IFC procedures.

The influence of verbal and nonverbal contextual factors on intelligibility was examined using sentences produced under varying conditions by a speaker with severe flaccid dysarthria. Contextual factors included (a) concurrent production of communication gestures, (b) predictiveness of message content, (c) relatedness of sentences to specific situational contexts, and (d) prior familiarization with the speaker. Sentences produced by the speaker were audio- and video-recorded and presented to 96 listeners/viewers who were assigned to three different methods of presentation of the stimuli: (a) audio+video, (b) audio-only, or (c) video-only conditions. Results indicated that gestures, predictiveness, and context influenced intelligibility; however, complex interactions were observed among these factors and methods of presentation of the stimuli. Results were interpreted in light of Lindblom's "mutuality model," indicating that when signal fidelity is poor, as in the present speaker with dysarthria, differing combinations of signal-independent information may be employed to enhance listener understanding of spoken messages.

The fact that stuttering runs in families has been documented over a long period and has led to speculations and research about the role of a genetic component to this disorder. Although the genetic factor cannot be proved by familial aggregation and twin studies alone, such research has continued to provide support for a relationship between stuttering and genetics. The purposes of this article are to review and critique the research in this area. The article first assesses research methodologies that have been employed in familial studies of stuttering. It proceeds to review and critique incidence, twin, and aggregation studies. In addition, it includes sections on subgroups, genetic models of stuttering, and implications for future research as well as for clinical work. With a focus on improved methodology and recent findings, a current perspective on our knowledge of the genetic component to stuttering is provided. Among other conclusions, the article emphasizes that failure to consider epidemiologic factors has probably biased previous results regarding the genetics of stuttering. New preliminary data also appear to provide evidence that spontaneous recovery and chronicity are influenced by genetic factors. Generally, however, the review of incidence and twin studies, as well as of evidence for the various inheritance models, confirms previous conclusions about the interaction between genetic and environmental factors in stuttering.