内分泌对变声的影响,最早观察的是性腺激素对变声的影响;稍后是甲状腺素;再后是垂体激素和各激素之间相互关系的探讨.研究最多的是男性性腺激素.中世纪后,欧洲盛行阉男女高音,十八世纪时达高峰(当时意大利每年竟有4000名男孩被去势).从而 Endocrine on the sound changes, the earliest observation is the effect of gonadal hormones on the vocal change; later is thyroxine; then the relationship between pituitary hormones and the various hormones .Most studies are male gonadal hormones .After the Middle Ages, Europe The popular male and female soprano eunuchs reached their peak in the eighteenth century (at the time, about 4,000 boys were castrated each year in Italy).