在睡觉的时候,身体各部的活动机能都降低了,全身的肌肉除了眼睛的环狀肌、膀胱和直腸的括約肌外都是松弛的。軟腭(即小舌)松軟,自由地悬在口中,在呼吸的时候受到气流的振动,就發出了声音。这就是鼾声。有时候因为舌头肌肉松弛,睡眠的位置不适合(如舌根后傾),气流冲击舌根,也能够發出鼾声。 At the time of sleeping, the function of the various parts of the body is reduced. The muscles of the body are loose except for the circular muscles of the eyes, the bladder, and the sphincter of the rectum. The soft palate (ie, the small tongue) is soft and freely suspended in the mouth. When it is breathed, it is vibrated by the air flow and sounds. This is the buzz. Sometimes because the tongue muscles are slack, the sleeping position is not suitable (such as the back of the tongue), the airflow hits the base of the tongue, and it can also make a buzzing sound.