Fig. 1. The discriminanda comprising elemental and transverse patterning problems. Elemental problems are presented in Sets 1 and 2, respectively, and the transverse patterning problem is presented in Set 3.

Fig. 2. Performance on the elemental discrimination problems before and after the damage to the hippocampus. Rats with damage to the hippocampal formation exhibit retrograde amnesia for elemental discriminations learned prior to surgery (A). Rats with damage to the hippocampal formation do not exhibit anterograde amnesia for simple discriminations, they can re-learn the set of elemental problems they were trained on before the damage, learn a new set of elemental problems, and retain it over a 10-day delay without the hippocampus (B). P's < 0.05.

Fig. 3. Learning of elemental discriminations occurs at a faster rate after the hippocampal damage. Rats require fewer trials to reach criterion when learning elemental discriminations after the damage to the hippocampus, regardless whether they are the same discriminations that were learned prior to damage (gray) or whether they are a completely new set of discrimination problems (white). P's < 0.05.

Fig. 4. Rats with hippocampal damage exhibit both retrograde and anterograde amnesia for transverse patterning discriminations. When tested after the damage, rats did not remember the transverse patterning problem they learned prior to damage (gray) nor were they able to re-learn it (white). P's < 0.05.

Discrimination training procedures are shown for each group (ED: elemental discriminations; TP: transverse patterning), and divided by the phases they were trained in