Strategies for spatial navigation: alternation in the terrestrial toad Rhinella arenarum.

MUZIO, RUBEN N.; MERELES, IVAN DAVID; DANERI, M. FLORENCIA

CABA

Congreso; XX Jornadas Anuales Multidisciplinarias de la SAB (Sociedad Argentina de Biología).; 2018

Sociedad Argentina de Biologia

Learning rules for spatial navigation associated with alternation is used in neurosciences for studying animal behavior and cognition. Spatial alternation allows individuals to sequentially explore different places in the environment. This strategy is widely observed in rodents and birds, but hasn´t been reported in amphibians. Using the toad Rhinella arenarum as a model of ancient terrestrial vertebrate we search for primitive learning mechanisms, which could have been present in a common vertebrate ancestor with mammals. Our previous results showed that toads can acquire the ability of spatial orientation performing a fixed turn response in a plus maze, but was unknown if they were able to orient themselves by a learned alternation rule. In the present study we trained 10 dehydrated toads using a T-maze in a water-finding task. Toads were trained to reach the goal (a container with water) during 20 daily sessions, 3 trials per session. Animals of the Experimental group had to follow an alternation turn rule at the decision point to find the reward; animals of the Control group had the rewarded container randomly located. Results revealed differences in the stategies to perform the task: a significative difference in the number of alternation trials (vs persistence) was observed for the Experimental group, while animals in the Control group performed a spontaneous persistence behavior. Although our results are promising, more studies will be needed to confirm the presence of this learning skill in amphibians.