Analysis of Speech Fundamental Frequencies for Different Tasks in Japanese.

PURPOSE: Speech fundamental frequency (SFF) assessment is essential for all dysphonia patients to effectively evaluate the therapeutic effects of voice therapy, especially in patients with disturbances in their voice pitch due to mutational dysphonia, Reinke's edema, or as side effects of hormone therapy. A standard method of SFF measurement remains unknown. Speech tasks such as sustained vowel phonation, counting, reading passage, and spontaneous speech have generally been used for SFF measurements. Ideally, spontaneous speech best reflects SFF; however, this task has not yet been clearly defined and is limited with regard to its adaptation to a clinical setting. A reliable task for SFF measurement in Japanese, which corresponds to a speech task that most closely reflects the value that would be observed with typical spontaneous speech, has not been investigated. This study aimed to identify a reliable speech task by measuring the SFF values elicited by different widely used speech tasks in Japanese, and assess its reliability and coefficient of determination (R2). METHODS: Sixty healthy volunteers (30 men and 30 women; aged 19-30 years; mean age 22.5 years) were enrolled. All experimental procedures were performed in Japanese. The SFF values for the speech tasks were determined through the voice samples recorded using a Pulse Code Modulation (PCM) recorder. Each task, except spontaneous speech, was repeated five times, and the average fundamental frequency in each task was determined as the SFF. To assess the reliability of the SFF values across daily variations within individual speakers, the SFF measurements were repeated on two different days, separated by at least 1 week. RESULTS: The SFF values of sustained /a/ phonation, sustained vowel-average, counting, reading passage, and spontaneous speech had excellent reliability, in terms of their reproduction based on intraclass correlation. Significantly high SFF values were observed, in decreasing order, for sustained vowels-average, counting, reading passage, and spontaneous speech in both males and females. The highest R2 for spontaneous speech was that of reading passage in both males (R2 = 0.771) and females (R2 = 0.806) (P < 0.01). CONCLUSION: When spontaneous speech was presented as a task most reflective of daily conversation, reading passage was determined to be the reliable task to assess the therapeutic effect of voice therapy in Japanese.

[Characteristics of childhood stuttering and suggestions for clinical practice].

Disfluency in an early phase of infancy should be addressed in the light of differences between stuttering and normal disfluency. When a direct approach is applied to an child who has become aware of his/her stuttering, it is importance to first make the child confront his/her stuttering and try to change it, and then to create a calm atmosphere receptive to any stuttering. Stuttering complicated by developmental disorders is characterized by the absence of variation characteristic of the symptoms of disfluency, or less variability. Children with this type of stuttering show lower levels of the adaptation effect and expectation anxiety, and develop few collateral symptoms. Furthermore, while they are aware of their stuttering, such children show no tendency toward internalization such as negative feelings/attitudes or embarrassment associated with stuttering. These findings may be useful in clinical practice for stuttering in childhood.