Martin F, Klingholz F
Laryngol Rhinol Otol (Stuttg). 1983 May;62(5):223-5.
Intraluminal esophageal manometry has been employed to study cricopharyngeal muscular function at different pitch levels. The activity of the cricopharyngeal muscle (CP) increases continually with rising pitch but is not influenced by the vocal sound pressure level. In the lower part of the chest register, the muscular pressure is lower than the pharyngo-esophageal pressure at rest. At high pitch levels, the pressure is higher than during swallowing. The CP has a dual function: With increasing pitch, the CP cooperates synergistically with the cricothyroid muscle (CT), indicated by increasing muscular pressure in the upper esophageal sphincter. On the other hand, the CP shortens the vocal cords by rotating the cricoid cartilage in anterior direction, thus acting antagonistically to the CT.
腔内食管测压已被用于研究不同音高水平下环咽肌的功能。环咽肌（CP）的活动随着音高的升高而持续增加，但不受嗓音声压级的影响。在胸声区的下部，肌肉压力低于静息时的咽食管压力。在高音高时，压力高于吞咽时。环咽肌具有双重功能：随着音高增加，环咽肌与环甲肌（CT）协同作用，表现为食管上括约肌肌肉压力增加。另一方面，环咽肌通过向前旋转环状软骨使声带缩短，从而与环甲肌起拮抗作用。
