Naomi Sakai

Brain activation in adults who stutter under delayed auditory feedback: An fMRI study

It is well known that some people who stutter (PWS) show an immediate reduction of stuttering when they speak under a condition of delayed auditory feedback (DAF). In the present study, to investigate cortical activations during speech production through the DAF effect, we performed functional magnetic resonance imaging (fMRI) experiments under the NAF (non-altered feedback) and DAF conditions for PWS and people who do not stutter (PWNS). The results are that (1) the PWS showed the higher activation in the right inferior frontal gyrus (Brodmann Area (BA)45) than the PWNS under the NAF condition; (2) the activations of the right superior temporal gyrus and the right middle temporal gyrus were higher under the DAF condition than the NAF in both PWNS and PWS groups; (3) the PWNS showed the higher activation in the right supplementary motor area and superior temporal gyrus than the PWS under both NAF and DAF conditions; (4) the PWNS showed the higher activation in the inferior frontal gyrus(the right BA45 and the bilateral BA46) under the DAF condition than the NAF. These results reconfirm most of the previous findings with some slightly different activation areas, and underscore the involvement of inferior frontal gyrus and superior temporal gyrus in dysfluency.

An Overview of Managing Stuttering in Japan

PURPOSE The purpose of this article is to describe the rapid development of speech-language pathology in Japan since governmental licensing started in 1997 and to summarize the current trends in assessing and treating stuttering for preschoolers, school-age children, adolescents, and adults. METHOD The authors review relevant information about the current assessment and treatment services for people who stutter in Japan and discuss the issues and challenges faced by speech-language pathologists in managing stuttering. CONCLUSION It is predicted that as expertise in stuttering grows in Japan, the role of stuttering specialists in allied health, school districts, and research will increase.

Japanese normative data for the Unhelpful Thoughts and Beliefs about Stuttering (UTBAS) Scales for adults who stutter

PURPOSE This study reports Japanese normative data for the Unhelpful Thoughts and Beliefs about Stuttering (UTBAS) scales. We outline the translation process, and evaluate the psychometric properties of the Japanese version of the UTBAS scales. METHODS The translation of the UTBAS scales into Japanese (UTBAS-J) was completed using the standard forward-backward translation process, and was administered to 130 Japanese adults who stutter. To validate the UTBAS-J scales, scores for the Japanese and Australian cohorts were compared. Spearman correlations were conducted between the UTBAS-J and the Modified Erickson Communication Attitude scale (S-24), the self-assessment scale of speech (SA scale), and age. The test-retest reliability and internal consistency of the UTBAS-J were assessed. Independent t-tests were conducted to evaluate the differences in the UTBAS-J scales according to gender, speech treatment experience, and stuttering self-help group participation experience. RESULTS The UTBAS-J showed good test-retest reliability, high internal consistency, and moderate to high significant correlations with S-24 and SA scale. A weak correlation was found between the UTBAS-J scales with age. No significant relationships were found between UTBAS-J scores, gender and speech treatment experience. However, those who participated in the stuttering self-help group demonstrated lower UTBAS-J scores than those who did not. CONCLUSION Given the current scarcity of clinical assessment tools for adults who stutter in Japan, the UTBAS-J holds promise as an assessment tool and outcome measure for use in clinical and research environments.

Automatic Discrimination of Soft Voice Onset Using Acoustic Features of Breathy Voicing.

Soft onset vocalization is used in certain speech therapies. However, it is not easy to practice it at home because the acoustical evaluation itself needs training. It would be helpful for speech patients to get objective feedback during training. In this paper, new parameters for identifying soft onset with high accuracy are described. One of the parameters measures an aspect of the soft voice onset, in which the vocal folds start to oscillate periodically before coming in contact with each other at the beginning of vocalization. Combined with an onset time exceeding a threshold, the proposed parameters gave about 99% accuracy in identifying soft onset vocalization.

Articulation rates of people who do and do not stutter during oral reading and speech shadowing

Purpose: Previous studies indicate that people who stutter (PWS) speak more slowly than people who do not stutter (PWNS), even in the fluent utterances. The present study compared the articulation rates of PWS and PWNS in two different conditions: oral reading and speech shadowing in order to elucidate the factor that affect the speech rate in PWS. Method: All participants were instructed to read aloud a text and to shadow a model speech without seeing its transcript. The articulation rate (mora per second) was analyzed with an open-source speech recognition engine “Julius” version 4.3.1 (https://github.com/julius-speech/julius). The pauses and disfluencies were excluded from the calculation of the articulation rate in the present study. Results: The mean articulation rate of PWS was significantly lower than that of PWNS only in oral reading, but not in speech shadowing. PWS showed a significantly faster articulation rate, comparable to that of the model speech, in shadowing than in oral reading, while PW...