In vitro expression of in vivo learning by an isolated molluscan CNS

The associative learning functions of the central nervous system of Limax maximus have been established with behavioral experiments on intact animals (Sahley et al., J. comp. Physiol., 144 (1981) 1) and physiological experiments on the isolated CNS (Culligan and Gelperin, Brain Research, 266 (1983) 319). We now report experiments in which memory states were established by behavioral training and read out by a test procedure applied to the isolated brains derived from the trained animals. With a success rate of one-half we found that isolated lip-brain preparations derived from previously conditioned slugs express in vitro the learning acquired in vivo.