Figure 1.

Acquisition and retention for three ITI groups, 30 sec, 3 min, and 10 min. For statistical evaluation, see text. The ordinate gives the percentage of animals responding to the CS. The abscissa on the left side of the figure gives the conditioning trials. (—○—) ITI 30 sec; (–□–) ITI 3 min; (–●–) ITI 10 min. The animals in the three groups were tested 30 min, 1 d, and 3 d after conditioning, respectively. n gives the number of animals.