Urge-to-cough: what can it teach us about cough?

Abstract

The Urge-to-Cough is a component of the brain motivation system that mediates cognitive responses to cough stimuli. There are six stages to the cough motivation-to-action system: (1) stimulus, the trigger for the neural event; (2) urge, the physical need to respond to the stimulus; (3) desire, translation of urge into a central neural targeted goal; (4) action, physical response that satisfies the urge-desire; (5) evidence, feedback to the neural system on the action; (6) reward, sensory system that determines if the urge was satisfied. Urge-to-Cough is related to three fundamental types of cough: (1) reflex cough, (2) voluntary cough, and (3) behavioral cough. Urge-to-Cough with reflex cough can be studied by measuring the sensations elicited by a cough stimulus. Neural processes with voluntary cough can be studied using magnitude production cognitive psychometric methods. Results of these studies have shown if the subjects can reliably estimate their Urge-to-Cough, the urge increases with increasing cough stimulus, there is a correlation between the Urge-to-Cough and cough intensity, there is a threshold for eliciting the sensation of the urge that precedes the motor cough behavior, subjects can voluntarily produce coughs of varying magnitudes, the motor cough pattern is directly related to the perceived magnitude of a cough, volitional triggers of a cough are directly related to the reflex cough pattern, and neural triggers of cough initiate a stereotypic motor output. Understanding the Urge-to-Cough motivation-to-action system opens new strategies for research on central neural cough mechanisms.