Fig. 4. Effects of different numbers of differential conditioning trials. (A) Stimulus schedules (see Fig. 1C for key to shading). Groups 1, 2 and 3 were subjected to one, two and three sets of P+/V- conditioning trials, respectively. Group 4 crickets were subjected to two elementary appetitive (P+) conditioning trials followed by two aversive (V-) conditioning trials. (B) Performance indices of groups 1-4 (N=29, 45, 24 and 22, respectively) 2 h, 1 day and 4 days after training. Values are means + S.E.M.