Fig. 3. Submerging in the same context after operant training prolongs the memory for operant conditioning. (A) Two 30 min sessions separated by 1 h in the standard context were followed by 3 days of submersion in the standard context. The test session in standard context was significantly different (asterisk; Fisher's LSD protected t-test, P<0.01) from Session 1, demonstrating a 3-day memory. A change of context test (carrot, CC) was not significantly different from Session 1 (Fisher's LSD protected t-test, P>0.05, N=14). (B) Two 30 min sessions separated by 1 h in carrot context were followed by 3 days of submersion in carrot context. The test session in carrot context was significantly different (asterisk; Fisher's LSD protected t-test, P<0.01) from Session 1, demonstrating 3-day memory. A change of context test (standard; CC) was not significantly different from Session 1 (Fisher's LSD protected t-test, P>0.05, N=14).