Methodological studies assessing context-dependent conditioning in prairie voles

• Brielle Seth, Neuroscience, University of Delaware

• Katelyn Rogers, Psychological and Brain Sciences, University of Delaware
• William Kenkel, Psychological and Brain Sciences, University of Delaware

Classical conditioning is when an association forms between a neutral stimulus, an unlearned stimulus that does not provoke a response, and an unconditioned stimulus, a stimulus that provokes an unlearned and involuntary response. Conditioned place preference (CPP) is a classical conditioning test examining the rewarding properties of stimuli based on context-dependent associations.  We have previously run CPP using an animal model, the prairie vole, to experimentally assess context-dependent associations. The aim of this project was to expand upon our previous findings to determine the rewarding properties of various stimuli.  To test rewarding properties, multiple stimuli were used such as sprinkles, bioserv pellets and sucrose solution for conditioning during CPP, and the strength of the association was measured by time spent in the conditioned chamber to determine the strength of preference. We also varied the time of exposure to the stimulus before testing where subjects were given sucrose in the home cage one day or two days before. In the preconditioning phase, the animal is allowed to freely explore the chamber. After the preconditioning phase is complete, there will be a calculated score of the animal in each chamber to figure out what the preferred and non preferred chamber is. There is a conditioning phase where the animal is paired with the unconditioned stimulus (sucrose) in the nonpreferred chamber and separately paired with the preferred chamber without any stimulus. Once conditioning is finished there is a testing phase where the animal is allowed to freely explore the chamber without any stimulus and the difference in time spent in the conditioned chamber before and after conditioning is used to determine strength of the association.  To further investigate reward properties, cesarean delivered voles and vaginal deliveries voles will be tested.