Supramedullary influences on cough.

Area of Science:

• Neuroscience
• Respiratory Medicine
• Physiology

Background:

• Supramedullary (higher brain centers) influences on cough are primarily inferred indirectly.
• Voluntary cough control and the urge-to-cough sensation are typically associated with the cerebral cortex.

Purpose of the Study:

• To explore the role of supramedullary structures, particularly the cerebral cortex, in modulating cough reflexes and voluntary cough.
• To highlight the limited experimental evidence and the need for further research into the neural control of cough.

Main Methods:

• Review of clinical observations and evidence from conditions affecting corticobrainstem pathways (e.g., stroke, Parkinson's disease).
• Consideration of the effects of voluntary inhibition, habit cough, placebos, sleep, and anesthesia on cough.
• Inference of cortical involvement based on observed modulations of cough.

Main Results:

• Disruption of corticobrainstem pathways impairs voluntary cough but not reflex cough.
• 'Habit cough' is hypothesized to be cortically mediated, similar to Tourette's syndrome.
• Placebo effects and complementary medicine treatments suggest cortical inhibition of clinical cough; cough is also depressed during sleep and anesthesia, likely at a cortical level.

Conclusions:

• The cerebral cortex plays a significant role in the voluntary control and modulation of cough.
• Evidence suggests supramedullary structures, especially the cortex, are involved in inhibiting cough, but their precise localization and function remain largely uncharacterized.
• The neural mechanisms underlying cough control offer a promising area for future experimental and clinical investigation.