음성장애 환자의 음질 평가를 위한 표준문장 개발

Development of Korean Standardized Sentences on Voice Quality Evaluation for Dysphonia

Purpose: The purpose of this study was to develop the Korean standardized sentences to elicit various laryngeal behaviors for voice quality evaluation and to investigate the validity of new developed sentences. Methods: Phoneme and word frequencies of Korean standardized passages (‘Fall’,‘Walk’) were analyzed and words were selected based on high- frequency words from speech corpus ‘Sejong’for the purpose of each sentence. Six standardized sentences were developed: sentence included Korean all vowels, sentence begins with the /h/ sound, sentence consisted of all voiced sounds, sentence elicits hard glottal attack, sentence incorporated nasal sounds, sentence weighted with voiceless plosive sounds. For verifying the effect of sentence type on voice quality, acoustic measures [speaking fundamental frequency (SFF), Cepstral peak prominence (CPP), low-to-high frequency ratio (L/H ratio)] were measured from 20 young speakers (10 males, 10 females) with normal voice. Results: Significant main effects for gender and sentence type appeared on the measurements of SFF, CPP, and L/H ratio. The largest amplitude of CPP and L/H ratio was produced in all-voiced sentence and the highest SFF was also presented in voiceless plosive consonant sentence in both males and females. Conclusion: Different consonant and vowel context in a connected speech affected the voice quality as well as frequency. Newly developed sentences consisted of various vowels and consonants may be useful to observe the different laryngeal behaviors and clinical signs as the connected speech stimuli.