98 Evaluating Social Reward in Socially Isolated Mice

Faculty Mentor: Moriel Zelikowsky (Neurobiology, University of Utah)

Previous research has shown that prolonged social isolation causes a social withdrawal phenotype in socially isolated (SI) mice. This social withdrawal has traditionally been viewed as a function of decreased social reward, though this theory has not been tested until now. To accomplish this, we designed a new Reward Box assay to directly test reward behavior and plan to begin experimentation this summer. Preliminary data from our 3-chamber behavior assay suggests that though isolated mice demonstrate a social withdrawal phenotype, social interaction may still be rewarding. The objective of this experiment is to test if mice view social interaction as inherently rewarding following social isolation.

The reward box consists of two infrared sensors and a stepper motor all controlled by an Arduino microcontroller. The main apparatus to which the electronic components will be mounted to is 3-D printed using a custom design. Following a training phase, both group housed (GH) and (SI) mice will be able to choose between two nose poke holes. Each hole has an infrared sensor behind it and will either immediately open the gate to reveal a conspecific “target” mouse or have a delayed opening following activation of the sensor.

The experiment and the research involved is still ongoing as it is still being designed and planned. From previous experiments it has been found that mice begin to exhibit social withdrawal phenotypes following social isolation, but no research has been done to directly test if social withdrawal of SI mice is related to lack of social reward.

Socially isolated mice show social withdrawal, but social reward has yet to be directly tested. This new behavior assay was designed to directly test this phenomenon. Both the GH and SI mice are expected to show a similar preference rate for the social port (sensor that immediately opens the gate) on the reward box. If the socially isolated mice however do not display this social seeking behavior, further testing will be required to see if they will activate a sensor to close the door to avoid this social interaction