Appetitive conditioning task in a shuttle box and its comparison with the active avoidance paradigm

The main features of the Shuttle Box Active Avoidance paradigm (e.g., the use of simple locomotor response as an operant and electrical current as a primary reinforcer) make this task easily automated. However, learning in this paradigm cannot be easily separated from the specificity of fear motivation. Punishment and negative reinforcement highly affect behavior in this task and complicate learning. In the present study, we describe a novel computer-controlled appetitive task in a shuttle box and compare it with active avoidance. The appetitive task was performed in the same shuttle box apparatus, additionally equipped with food dispensers in each compartment, and using a similar protocol. The reinforced reaction included the transition to the feeder in the opposite compartment in response to a stimulus. Animals mastered the appetitive task faster than the active avoidance task in the shuttle box. Other major differences between the models were the number and dynamics of intertrial responses (ITRs). Whereas in active avoidance the number of ITRs was low during learning, in the appetitive task rates were higher and they persisted throughout learning. Overall, the findings demonstrate some benefits of the appetitive task as a control condition to active avoidance: the use of a similar reaction and apparatus, no prior habituation, and fast acquisition.