Side Preference in a Two Choice Discrimination Study

     Exploring side preferences in the early experimental stages of a two choice olfactory discrimination study allows for a more accurate assessment of the collected data.  By analyzing a subject’s side preference, it can be more correctly determined whether the subject is deliberately selecting the S+ scent, or if indication of the S+ scent is due to chance alone.  The intention of this analysis is to determine whether or not side preferences exist in the early experimental stages of the two choice olfactory discrimination study.  The study consists of a training stage, and three discrimination tasks.  These tasks consist of estrus versus no scent (H₂O), estrus versus diestrus, and estrus versus proestrus.  In each, estrus urine is designated the S+ scent, and the subjects are rewarded for selecting the correct choice.  Each subject is taken through twenty trials per session, during which both the side and accuracy of their choice is recorded.  To advance from one task to the next, the subjects must perform at or above eighty percent correct. 

     Thus far, the data suggests a reliance on side preferences for reinforcement during the early stages of the discrimination tasks.  Each of the three subjects who have participated in the first discrimination task have shown, at the very least, an inclination to choose one side (left or right) over the other side.  The data also suggests that side preference decreases as accuracy increases.  As data continues to be collected, it will be interesting to determine whether the side preference trend continues among other subjects and tasks, or if it only exists in specific subjects undertaking particular tasks.