Human subjects rated the time course of the burn produced by three concentr
ations of capsaicin applied to the tongue via filter papers. Data were fit
to a dynamic model composed of a level detector, a change detector, and a d
ouble integrator. These three processes responded differently to concentrat
ion. 6-n-Propyl-2-thiouracil (PROP) taster status correlated positively wit
h the integrator process. Although a minority of subjects showed evidence o
f the integrator process, any subject with an integrator process at a given
concentration also showed it at any higher concentration. (C) 2001 Elsevie
r Science Inc. All rights reserved.