AVOIDANCE AND HYPOALGESIA INDUCED BY NOVEL ODORS IN MICE

Male mice strongly rejected the odors of soiled or unsoiled cat litter relative to unsoiled conspecific bedding and preferred conspecific soiled bedding in a four choice preference/rejection test. In a subsequent experiment, mice also strongly rejected the odors of cinnamon, and chocolate relative to unsoiled bedding. Brief exposure to the odor of unsoiled cat litter increased jump thresholds to footshock whereas cinnamon odor increased both flinch and jump thresholds. The results suggest that novelty contributes importantly to the increased defensiveness and hypoalgesia produced by the odors of potential predators.