Laryngeal manual therapy as a treatment for impaired production of tahrir vibrato in traditional Iranian singers.

ABSTRACT

BACKGROUND: Iranian vibrato (tahrir) is a common feature of traditional Iranian singing. A unique feature of tahrir is a modulated voice quality perceived as a rhythmic falsetto voice break associated with upward pitch inflections. Laryngeal discomfort and impaired voice quality can occur in singers when they perform Iranian tahrir using an improper technique. AIM: A case series research design was used to explore voice treatment outcomes using laryngeal manual therapy (LMT) for treating voice problems associated with tahrir singing. METHOD: Four professional Iranian singers of the traditional style (3 men and 1 woman) were studied. All subjects reported difficulty executing tahrir during performances. They were assessed by a speech-language pathologist (SLP) specializing in the administration of LMT for voice disorders. Multidimensional assessments were made of the participants' vocal function using acoustic and auditory-perceptual evaluation, self-reports of the singers, and LMT assessments by the SLP before and after treatment. The therapeutic program implemented LMT techniques to release laryngeal joints and reduce muscular tension. RESULTS: Pretreatment examination of the larynx and anterior neck musculature using palpation showed that the difficulties in producing tahrir vibrato were associated with a decreased thyrohyoid space and tension in the submental complex and sternocleidomastoid. Posttreatment examination showed an increased thyrohyoid space and reduced tension in the submental complex and sternocleidomastoid, associated with the singers' perception of reduced effort producing tahrir vibrato during singing. CONCLUSION: Tahrir vibrato requires specific training to prevent excessive tension in laryngeal and neck muscles. In the absence of such training, or in the context of excessive singing associated with fatigue, LMT may facilitate more efficient vocal production in tahrir singers.