Fig. 2. Effects of two-trial conditioning. (A) Stimulus schedules (see
Fig. 1C for key to shading).
Groups 1, 2 and 3 were subjected to two trials of differential conditioning
(P+/V-) and elementary aversive (V-) and appetitive (P+) conditioning,
respectively. (B) The preferences (PPIs) for peppermint of groups 1
(N=29), 2 (N=15) and 3 (N=18) before training and 2
h after training. Values are means + S.E.M. (C) Performance index (PI) of
groups 1, 2 and 3 measured 2 h, 1 day and 4 days after training. Values are
means + S.E.M.
