A Nasoendoscopic Study of "Head Resonance" and "Imposto" in Classical Singing.

BACKGROUND: Classical singing pedagogy uses many concepts which lack precise definition and whose acoustic and physiologic correlates are unclear. This study focuses on the concepts "head resonance" and "imposto." In singing guidebooks, head resonance has been described as causing vibratory sensations on the face and head, auditively it has been described as a bright color especially predominating in the higher pitch range. "Imposto" has been related to the sensation of "air flow" or "sympathetic resonance vibrations" on or over the upper bridge of nose, and it also has been pursued using a "closing mechanism of the upper respiratory track" (activation of nasalis muscle). STUDY DESIGN: Experimental cross-sectional study. METHOD: Five subjects (three classical singers, one amateur singer, and a nonsinger) were investigated with nasofiberoscopy during phonation. The singers were instructed to sing [i:] on one comfortable self-chosen pitch in three ways: (1) without head resonance, (2) with head resonance, and (3) using imposto (exploiting the nasalis muscle). The nonsinger was investigated without phonation, while just holding his breath after inhalation first normally and then while producing imposto. The following measurements were made on the fiberoscopic images: (1) height of soft palate, (2) area of the hypopharynx, (3) area of the epilaryngeal tube inlet. RESULTS: The singers raised the soft palate and narrowed the epilaryngeal inlet during head resonance and even more during imposto. The pharynx to epilarynx ratio increased. Similar narrowing of the epilaryngeal tube inlet was observed in the nonsinger when constricting the nasalis, CONCLUSIONS: The results suggest that both the head resonance and imposto are related to control of the pharyngeal space and epilaryngeal tube, and that the nasal muscles may be used as an aid in regulating the epilaryngeal tube width, which in turn, improves the voice-source -tract interaction.

The Nasal Musculature as a Control Panel for Singing-Why Classical Singers Use a Special Facial Expression?

OBJECTIVES: This study aimed to explain the possible reason why classical singers seem to spread their nostrils and raise their cheeks before starting to sing. STUDY DESIGN: This is an experimental study. METHODS: Five subjects (three classical singers, two nonsingers) were investigated with nasofiberoscopy holding their breath after inhalation. The subjects were instructed to have a neutral expression first and then to take the singers' expression characterized by nostril flaring. In case of nonsingers, the special expression was rehearsed beforehand, guided by a classical singer. The following measurements were made: (1) height of soft palate, (2) area of the hypopharynx, (3) area of the epilaryngeal tube inlet (Aditus laryngis), and (4) dimensions of the (visible) glottis (length, width, and length-to-width ratio). RESULTS: All subjects raised the palate and widened the pharyngeal inlet, epilaryngeal inlet, and the glottis during "singer's expression." CONCLUSIONS: The results suggest that classical singers may take advantage of breathing- and smelling-related connections between nasal and facial muscles and the larynx to avoid a hard glottal attack and pressed phonation and possibly also to assist the production of mixed register (head voice), characterized by a relatively low adduction between the vocal folds.