Central nervous system control of the laryngeal muscles in humans

Abstract

Laryngeal muscle control may vary for different functions such as: voice for speech communication, emotional expression during laughter and cry, breathing, swallowing, and cough. This review discusses the control of the human laryngeal muscles for some of these different functions. Sensorimotor aspects of laryngeal control have been studied by eliciting various laryngeal reflexes. The role of audition in learning and monitoring ongoing voice production for speech is well known; while the role of somatosensory feedback is less well understood. Reflexive control systems involving central pattern generators may contribute to swallowing, breathing and cough with greater cortical control during volitional tasks such as voice production for speech. Volitional control is much less well understood for each of these functions and likely involves the integration of cortical and subcortical circuits. The new frontier is the study of the central control of the laryngeal musculature for voice, swallowing and breathing and how volitional and reflexive control systems may interact in humans.

Neurogenesis of cough, other airway defensive behaviors and breathing: A holarchical system?

“…In the absence of such regulation, effective airway protection during swallow is not possible. Swallowing is typically considered to be an ingestive behavior, however, this behavior can have an airway protective function in that it removes ejected material from the pharyngeal airway (Ludlow, 2005).…”

Efeitos da terapia manual laríngea e da estimulação elétrica nervosa transcutânea (TENS) na diadococinesia laríngea em mulheres disfônicas: estudo clínico randomizado

“…Only the laryngeal DDK of vowel /i/ provided a significant difference following LMT intervention (Table 1), which points to the importance of using both vowels for assessment of laryngeal diadochokinesis. That is because, according to Ludlow et al (29) , there are differences in the use of laryngeal muscles among individuals during sound production that would lead to changes in supraglottal structures that cause changes in subglottal tension, opening, and pressure of vocal folds. In addition, a possible difference in the use of suprahyoid and articulatory musculature during the production of the vowels is assumed, which would lead to different diadochokinetic findings for each vowel.…”

Respiratory, postural and spatio-kinetic motor stabilization, internal models, top-down timed motor coordination and expanded cerebello-cerebral circuitry: a review

“…Controversy exists as to whether the models so acquired are stored in the cerebellum , or cerebral cortex areas such as the parietal area . The actual submovements so scheduled for task mastered motor skills might be directly controlled from the cerebral cortex (Heffner and Masterton, 1983;Kuyper, 1958;Liscic et al, 1998;Ludlow, 2005;Maertens de Noordhout et al, 1999;Teitti et al, 2008), or involve in a hierarchical manner of delegation, lower areas in the supraspinal nervous system, such as the cerebellum and other subcortical areas (van der Linden et al, 2007), and/or, processes lower down in the spinal cord (Kimura et al, 2006;van der Linden et al, 2007). Related this top-down control, the supraspinal adjustment of long-latency (45-100 ms) reflexes can also draw upon the cerebello-cerebral internal models of limb dynamics (Kurtzer et al, 2008).…”

“…For example, the human cerebral cortex has considerably enhanced access to spinal motorneurons (Lemon, 2008) and so gained direct control over finger and hand muscles (Heffner and Masterton, 1983;Teitti et al, 2008), and lower limb ones (Maertens de Noordhout et al, 1999). Similarly humans show direct control over the larynx and face (Ghazanfar and Rendall, 2008;Kuyper, 1958;Liscic et al, 1998;Ludlow, 2005).…”

“…This suggests that nonhuman apes have problems unlocking the separate musculoskeletal elements that make up the vocalization chain to create the motor coordination that underlies the motor production of human speech. That the nonhuman vocal chain should be locked in this way makes evolutionary sense in the view of the critical importance of the links of respiration to cardiovascular and locomotion (Lee and Banzett, 1997), and that the larynx is involved not only in phonation but also in several survival critical reflexive actions such as swallowing, respiration and cough (Ludlow, 2005).…”