Representation of capsaicin-evoked urge-to-cough in the human brain using functional magnetic resonance imaging

Am J Respir Crit Care Med. 2007 Aug 15;176(4):327-32. doi: 10.1164/rccm.200612-1856OC. Epub 2007 Jun 15.


Rationale: Coughing in humans is typically preceded by a desire (or urge) to cough. The neural circuitry involved in sensing airway irritation and generating the urge-to-cough in humans is essentially unknown.

Objectives: The aim of the present study was to use functional brain imaging to describe the supramedullary regions that are activated in humans during capsaicin inhalation.

Methods: Experiments were performed on 10 healthy subjects (5 males, 5 females). Capsaicin doses were individually tailored to evoke a transient and reversible urge-to-cough. Blood oxygen level-dependent (BOLD) functional magnetic resonance measures were collected during repeated 24-second challenges with capsaicin or saline inhalation and subjects were asked to rate the urge-to-cough intensity of each challenge.

Measurements and main results: Capsaicin inhalation reliably evoked an urge-to-cough, which was associated with activations in a variety of brain regions, including the insula cortex, anterior midcingulate cortex, primary sensory cortex, orbitofrontal cortex, supplementary motor area, and cerebellum.

Conclusions: These data provide the first insights into the cortical neuronal network involved in sensing airway irritation and modulating coughing in humans.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Administration, Inhalation
  • Adult
  • Brain / physiology*
  • Capsaicin / administration & dosage*
  • Cough / chemically induced*
  • Female
  • Humans
  • Irritants / administration & dosage*
  • Magnetic Resonance Imaging*
  • Male
  • Middle Aged
  • Nasal Provocation Tests
  • Reflex / physiology


  • Irritants
  • Capsaicin