The ability of man to detect added resistive loads to breathing.

1. Resistive loads were added to the airways of patients with tracheostomies; the patients were blindfolded and the loads introduced without their knowledge. 2. The ability to detect the loads was the same in a patient with C3 transection (chest wall and diaphragm disconnected from the brain) as in a control group of patients with no neurological lesion. 3. It is concluded that receptors in the chest wall and diaphragm are not involved in the genesis of the sensation by which added resistive loads are detected.