Sign- vs. goal-tracking in a feature positive discrimination task with nicotine: importance of spatial location of the conditional stimulus

We assessed whether sign-tracking developed along with goal-tracking in a Pavlovian drug discrimination task. Rats had nicotine sessions intermixed with saline sessions. For nicotine sessions, 15-s illumination of a light near (Experiment 1) or far (Experiment 2) from the dipper receptacle was followed by sucrose. Saline sessions were similar to nicotine sessions except sucrose was withheld. Regardless of location, the light evoked goal-tracking only on nicotine sessions. Only rats with the light near the dipper developed sign-tracking.