This study has been carried out mainly for the purpose of clarifing phonatory mechanism in both easy and minimum intensity phonations. Phonatory examinations were applied in normal and pathological cases by use of phonolaryngography by which fundamental frequency, intensity and air flow rate during phonation are able to be simultaneously examined. In order to obtain three different coefficients of correlation, average flow rate vs fundamental frequency, intensity vs fundamental frequency and intensity vs average flow rate in easy and minimum phonations, further study has been statistically performed. The statistical study indicated the following results; 1) In normal cases, no dominant difference was obtained among each correlation coefficient between easy and minimum phonations. 2) In cases of insufficient glottal closure and small mass on the vocal folds, highly positive correlation coefficient was observed in average flow rate vs intensity and fundamental frequency vs intensity among both easy and minimum phonations while there was no significant difference between the both phonatory modes. 3) In cases of stiffened vocal folds and large amount of mass on the vocal fold, notable difference of the coefficient of correlation between the two types of phonation modes was obtained.
