Contraction of the pharyngeal constrictor muscles that surround the throat. Or, the “pharyngeal squeeze.” It is the primarily the middle and inferior constrictor muscles that contract. When these muscles contract, they tense and narrow the pharynx. This action is particularly important for swallowing.
The pharynx also contracts when a person produces voice above a certain pitch in his or her range. The threshold for pharynx contraction depends in part on a person’s sex and age, and in women with peri-menopausal voice change (a condition in which they lose some capability and comfort in their upper vocal range), the pharynx will contract at a much lower pitch than otherwise expected. Thus, a clinician trying to diagnose peri-menopausal voice change can endoscopically view a patient’s pharynx and elicit different vocal tasks to see if the voice’s “muscular ceiling”—where the pharynx begins to contract—has lowered or not.
Photos:
Pharynx contraction (1 of 2)
The pharyngeal constrictor muscles are relaxed during low-pitch phonation. Notice the open pyriform sinuses.
Panoramic view, A3 (1 of 3)
Panoramic view of laryngopharynx of an older middle-aged woman singing A3 (220 Hz). Pharynx here is uncontracted and both pyriform sinuses (within dotted lines) are maximal in size.
Contraction, A4 (2 of 3)
At A4 (440 Hz), the pharynx has begun to contract, and the pyriform sinuses have begun to close.
Maximal contraction, F5 (3 of 3)
At F5 (698 Hz), the pharynx is nearly maximally contracted and pyriform sinuses nearly closed completely. Sustained singing at this pitch and above will be effortful and cause discomfort, unless this singer can learn to “de-recruit” pharynx contraction via technical changes of voice production.
Pharyngeal paralysis (1 of 2)
View of the laryngopharynx. This patient has pharyngeal paralysis on one side, which is already slightly evident because the posterior pharyngeal wall's midline (dotted line) is deviating here slightly to one side, even at rest.
Pharyngeal paralysis, more obvious with pharynx contraction (2 of 2)
The pharynx is contracted, and the posterior pharyngeal wall (midline again at dotted line) now deviates dramatically toward the non-paralyzed side of the pharynx. This pharynx contraction was elicited via extremely high-pitched voicing.
Pharynx contraction (1 of 2)
At low vocal pitch, the pharynx is uncontracted; pyriform sinuses are both widely open.
Pharynx contraction (1 of 2)
Laryngopharyngeal view of a young woman, phonating at F4 (~349 Hz). Here the pharynx is relaxed: notice the broad arc of the pharyngeal wall (green dotted line) and the widely open pyriform sinuses (blue dotted lines).
Pharynx contraction (2 of 2)
Same patient, now phonating at C5 (~523 Hz). The pharynx has contracted: notice the narrower, more pointed arc of the pharyngeal wall (green dotted line) and that the pyriform sinuses (blue dotted lines) are nearly closed. In this relatively young soprano, this degree of pharyngeal contraction should not occur until she sings as high as G5 (~784 Hz) or higher. This singer is experiencing loss of expected upper range—a lowered “muscular” ceiling of the voice.