Fig. 4. Behavioral response of Belly F1 snails after a single 0.5 h training session (TS). Operant conditioning of Belly F1 snails results in an LTM that persists for 24 and 72 h (24 h TM, N=26, P<0.05; 72 h TM, N=26, P<0.05). Yoked control snails do not demonstrate memory at these same time periods (faded-black bars, 24 h yoke, N=24, P=0.55; 72 h yoke, N=25, P=0.73). Snails did not demonstrate memory after 1 week (1 week TM, N=25, P=0.82). Results are shown as means + s.e.m. ^**P<0.001.