Fig. 6. Extinction training following intermediate-term memory (ITM) training prevents the augmentation of memory retention. (A) A cohort of 20 naïve snails received the ITM training procedure as in Fig. 1. Following a 2 h rest interval, these snails received extinction training (AE) before receiving the long-term memory (LTM) training procedure. Note that extinction training obliterated ITM. That is, the number of attempted pneumostome openings in session 4 was significantly different from that in session 3 (P<0.01) and was not significantly different from that in session 1 (P>0.05). The LTM training procedure resulted in a memory that persisted for 48 h. That is, the memory test (MT) was not significantly different from session 6 (NSD, P>0.05), but was significantly different from session 1 (P<0.01). (B) As in A, except that LTM was tested 72 h after the last LTM training session. Memory was not present because there was a significant difference between session 6 and MT (P<0.01) but no significant difference between MT and session 1 (NSD, P>0.05).
