Odor-cued taste avoidance: a simple and robust test of mouse olfaction.

In odor-cued taste avoidance (OCTA), thirsty mice, offered either an odorized nonaversive fluid (S+) or an odorized aversive fluid (S-), quickly learn to use odor to avoid drinking the S-. Acquisition of both odor detection and odor discrimination tasks is very rapid with learning evidenced in most cases by either long response times or total avoidance on the second presentation of the S- stimulus. OCTA is perhaps one of the simplest conditioning procedures for assessing olfaction in mice; it requires only a test box, drinkometer circuit, and thirsty mice accustomed to drinking in the apparatus. Its advantages over the most commonly used alternatives, habituation-dishabituation, and the mouse dig test, are discussed.