I am quoting a good overview from a Quora member about the reasons why people stutter when exposed to stress:
...The underlying physiological basis of why stress provokes stuttering has been addressed by Weber & Smith, (1990). It shows that speaking increases autonomic activity (elevated blood flow, increased heart rate, sweating) and that this sympathetic arousal was correlated with increased stuttering behaviors in stutterers. Interestingly, the sympathetic arousal of stutterers was found not to be outside the range of controls. The authors bring up several hypotheses as to why sympathetic activity may deteriorate speech fluency in stutterers:
Increased autonomic activity has been associated with irregular breathing, which may affect speaking;
Release of the stress hormone adrenalin may induce muscle tremor and spasms that can affect speech production;
Sympathetic regulation of afferent control of the sensitivity of sensory receptors (muscle spindles and mechanoreceptors) in the oralmotor, laryngeal and respiratory system may affect speech motor processes;
The gain of reflex arches (feedback) involved in the musculature engaged in speech may be modulated such that speech fluency is negatively impacted.
Unfortunately, clinical research in this field is not that advanced and good evidence on human studies is yet to be seen.
My question is whether we already know compounds whose mechanisms can in theory help to deal or ameliorate these pathological process in stutterers?