The development of birdsong and development of human speech share some features; both are complex sounds used for communication, and learning is acquired and restricted to youth. Song learning takes place in two periods, a sensory phase of song memorization and a sensorimotor phase of producing from the memory. The stage of song development where song becomes stable and stereotyped is called crystallization. Thereafter, adult birds usually do not learn new song. It is not known which stage impedes adult learning, however. We first postponed the sensorimotor phase using a noise-masking method and analyzed the songs over a long time period. The memory of song phonology persists well after the normal critical period, and the adult birds were able to use it to shape their songs and even retune their drifted songs. However, they never amended the syntax. Thus, the sensorimotor phase for phonology is not restricted to youth, and different schedules and processes may govern the learning of syllable phonology and syntax. Next, we deprived young birds of the model song and postponed the sensorimotor phase, to examine whether the sensory phase is limited to youth. Adult birds even without previous experience of hearing or singing a song failed to learn a song. Thus, neither song memorization nor song crystallization terminates the sensory period, and age per se limits the ability or motivation to learn song.
This article provides a brief overview of approaches used to treat adults who stutter that directly target speech behaviors, especially fluency shaping, stuttering modification and the integrated approach. We referred to outcomes of research into the efficacy of these approaches conducted in recent years. Future issues in the field of adult stuttering therapy in Japan were discussed. It is necessary to develop assessment tools which have adequate reliability and validity and to improve the expertise in stuttering of speech-language-hearing therapists. We also need more clinics and hospitals which can treat adult stuttering cases and more and better research into treatment outcomes.
Autologous fat augmentation of the vocal folds has become widely adopted as a means of vocal rehabilitation in patients with deficient glottal closure. In general, the injection method using autologous tissues presents no problems regarding safety issues such as infection of unknown cause, but the period of continuous effect is not constant because absorption may occur after injection. The details of postoperative course were reported for 99 cases during the 8 years from August 2003 to April 2011. In all cases, maximum phonation time was improved. In animal experiments using dogs and rabbits, it was confirmed that the decreased effectiveness caused by absorption after injection can be reduced by administration of platelet-rich plasma (PRP).
Several methods to restore voice in laryngectomees have been developed, including tracheo-esophageal voice with prostheses. Two different types of vocal prosthesis, the Groningen voice button and Provox 2, are available in Japan. While both are widely regarded as good methods, little has been reported comparing prosthetic vocal quality and function of different vocal prostheses used in the same patient. Six laryngectomees had their vocal prosthesis changed from the Groningen voice button to Provox 2 as of June 2011. The data regarding these six patients is the basis of this study. Voice quality was assessed by perceptual voice analysis using speech articulation, and vocal function was assessed by acoustic measures (maximum phonation time and fundamental frequency) and spectrum analysis (pitch perturbation quotient [PPQ] and amplitude perturbation quotient [APQ]). Each patient also completed VHI-10 and original questionnaires. There was no significant difference in vocal quality or function between the two types of vocal prosthesis and no patient complained of any vocal change. One patient developed a salivary fistula, but this was easily handled with suturation. There seemed to be no difficulty or difference in the changing of voice prostheses, which suggests that voice prostheses can be changed without any negative impact on the patient.
Speech rate control is a common approach to speech rehabilitation for patients with dysarthria. There are several different rate control methods and their efficacy varies by dysarthria type and among individuals. As we sometimes encounter dysarthric patients in clinical practice who seem to have difficulties in perceiving and memorizing tempo, knowing how they perceive and memorize speech rate would appear to be one of the important prerequisites for rehabilitation intervention based on rate control methods. In this study, five dysarthric patients, 13 healthy young individuals and 10 healthy elderly individuals performed seven different tests to investigate the following outputs and abilities: rates of speech and tapping produced with and without listening to reference samples, perception of speech and tapping rates, and differentiation of regular rhythms from irregular ones. The healthy individuals performed well on all seven tasks, while some patients with dysarthria experienced problems with tempo perception and memorization. These findings suggest that perception and memorization functions for speech rate in dysarthric patients need to be assessed first in rehabilitation interventions to determine an appropriate speech rate control method.
In this study we investigated the cognitive abilities underlying Hangul reading development from grade 1 to 4 in Korean children. We tested Korean children for their abilities to read (reading accuracy and fluency), cognitive abilities including phonological and visual processing related with reading skill, and size of vocabulary. In Hangul reading accuracy, the factors of phoneme awareness, syllable awareness, naming speed and lexicon were unique predictors based on the results of multiple regression analyses. The naming speed factor was a unique predictor only in grade 1, the phoneme and syllable awareness factors were unique predictors until grade 2, and the lexicon factor was the most unique predictor from grade 3 to 4 for accurate reading. In Hangul reading fluency, naming speed, syllable awareness, and lexicon were unique predictors based on the results of the multiple regression analyses. Moreover, the results showed that naming speed contributed substantially to reading fluency in all grades. In reading fluency, similar to reading accuracy, syllable awareness was a unique predictor until grade 2. These findings suggest that the relative importance of underlying skills as predictors of reading accuracy and fluency may change during the course of development.
In this study we observed 8 hearing-impaired preschoolers whose average hearing level was 72.6 dB (48.7-92.5 dB, 1 SD 18.7) in inclusive settings twice over the course of a year, and analyzed how their communicative behavior, MLUm and social maturity, along with the attitude of their hearing peers, influenced their cooperative play. The results revealed that they generally developed their play levels by the second observation, and most notably they participated in cooperative play significantly at 6 years old. Their MLUm did not lengthen although their communication behavior marked progress during the year. Hearing-impaired children construct cooperative play by nonlinguistic cues or appreciation of the situation. It is important for individual evaluation and educational treatment to enrich social play development using proper language contents and constructions. Participating in cooperative play needs both social maturity in the hearing-impaired children and appropriate attitude in their hearing peers. The results suggest that preparation of inclusive settings is useful in terms of both these factors.
Purpose: Criteria for spasmodic dysphonia (SD) as an independent voice disorder have not yet been established, and the current standardized assessment method is not sufficient for objective evaluation of severity or its effects. The purpose of this study was to quantitatively evaluate phonatory breaks and to demonstrate the characteristics of voice symptoms in abductor spasmodic dysphonia (ABSD). Method: Subjects included eight patients with ABSD and ten normal controls. We measured voice onset time (VOT) for the word-initial voiceless consonant /ta/ in the word "taiyo" under three different conditions (1. without punctuation, 2. with a comma, and 3. with a period) which appeared in the reading task "kitakaze to taiyo." Results: Under the conditions in which a comma or period was included, the patients' VOTs for the word-initial voiceless consonant were significantly longer than those of the controls. Prolongation of the VOTs was related to the length of the silence preceding the syllables. Conclusion: VOT measurement for the word-initial voiceless consonant was suggested to be a useful method to quantify voice symptoms of ABSD.
We examined the period in which hearing-impaired infants start using case particles in sign language communication. The subjects were four hearing-impaired infants who have been undergoing language training based on the Kanazawa (written-oral language) method since birth. 1) The hearing-impaired children started using case particles between 1 year 11 months and 2 years 2 months of age, which was almost the same as the normal-hearing children. 2) The first case particle was "wo" for all four cases. 3) The findings indicated that even hearing-impaired children can understand and express Japanese language the same as normal-hearing children by using Japanese sign language vocabulary and sentences (fingerspelling or sign language for postpositional particles) from early childhood.