Figure 1.

Acquisition of conditioned food cup (A) and freezing (B) responses in the food omission cue (A) and shock cue (B) training sessions of experiment 1. The leftmost points in A show performance to the light cue on the final light conditioning session. The group designations indicate the nature of training received. Group O-S received training with both a food-omission cue and a shock-paired cue, group OC-S received training with a shock-paired cue and with a control cue unpaired with food or food omission, and group O-SC received training with a food omission cue and a control cue unpaired with shock. There were 12 rats in each behavioral training condition.