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Background: Verbal communication is a human feature and volitional vocalization is its basis. However, little is known regarding the cortical areas involved in human vocalization. Methods: Therefore, functional magnetic resonance imaging at 3 Tesla was performed in 16 healthy adults to evaluate brain activations related to voice production. The main experiments included tasks involving motor control of laryngeal muscles with and without intonation. In addition, reference mappings of the sensorimotor hand area and the auditory cortices were performed. Results: Related to vocalization, in addition to activation of the most lateral aspect of the primary sensorimotor cortex close to the Sylvian fissure (M1c), we found activations medially (M1a) and laterally (M1b) of the well-known sensorimotor hand area. Moreover, the supplementary motor area and the anterior cingulate cortex were activated. Conclusions: Although M1a could be ascribed to motor control of breathing, M1b has been associated with laryngeal motor control. Consequently, even though M1c represents a laryngeal sensorimotor area, its exclusiveness as suggested previously could not be confirmed. Activations in the supplementary motor area and anterior cingulate cortex were ascribed to “vocal-motor planning.” The present data provide the basis for further functional magnetic resonance imaging studies in patients with neurological laryngeal disorders.

Objectives: To describe the course of the superior laryngeal nerve (SLN) and its branches, in particular, with regard to supraglottic motor and sensory functions. Methods: In 30 normal human hemilarynges, the SLN with its internal (intSLN) and external branch (extSLN) were dissected under microsurgical conditions and marked with acrylic dye. All anatomic structures of the larynges (muscles, cartilages, and ligaments) were dissected in detail. Results: The intSLN subdivides into three branches. The superior branch (I) runs to the lingual (extralaryngeal) part of the epiglottis and sends small fibers through the epiglottic foramina to the laryngeal surface. The middle branch (II) runs through the aryepiglottic fold into the ventricular fold, and the inferior branch (III) to the piriform sinus and to the postcricoid region, forming various anastomoses (e.g., ansa galeni) with the recurrent laryngeal nerve (RLN). The extSLN runs to the cricothyroid muscle (CT) and sends a branch through the CT along the lower rim of the thyroid cartilage into the larynx and up to the ventricular fold. This ventricular branch is a potential candidate for the innervation of the ventricular muscle (VM). Conclusions: Our results may contribute to a better understanding of supraglottic actions that provide primary functions of the larynx (such as swallowing, coughing, and breathing). An enhanced knowledge of neurolaryngology also provides a basis for interpreting disorders or paralyzes following surgical treatments (e.g., thyroid surgery, partial laryngectomy) and helps to lower the risks.