Vertical Larynx Height during Vocal Frequency Change

Vertical larynx height was filmed and thyrohyoid muscle activity sampled in two subjects during continuous and discrete-interval vocal frequency change. For continuous frequency change (glissando), the results showed a high positive relationship between larynx height and vocal fundamental frequency (r=0.93) within the modal register, a moderate relationship within the falsetto register (r=0.42), and no relationship within the pulse register (r=0.01). Discrete-interval frequency change showed a similar pattern of larynx height as in continuous change, with the absolute position of the larynx height as in continuous change, with the absolute position of the larynx in the two conditions ±5 mm at matching frequency points. Thyrohyoid muscle activity level was always found to be directly related to vertical larnyx position.