Fig. 3. RPeD1 soma ablation and memory formation. Ablating RPeD1 somata 2 days before training does not affect the snails' (N=20) ability to learn. That is, there is a significant difference between Session 1 and Session 2. In addition, these snails (N=20) can form intermediate term memory (ITM). That is, in a memory test (MT) 2 h after the last training session, the criteria for memory are met. However, if the memory is tested 24 h later in these same snails (N=20), the criteria for memory are not met. We conclude that RPeD1 soma-ablated snails do not form long-term memory (LTM).