Laboratory mice can behaviorally discriminate between natural and synthetic ultrasonic vocalizations

Abstract

Mice produce spectrotemporally complex ultrasonic vocalizations (USVs), thought to be important for social interactions such as mating. Previous research has established that mice are capable of detecting and discriminating natural, synthetic, and altered USVs using behavioral methodologies. The current study examined whether mice are capable of discriminating natural USVs from their synthetic USV analogs. Discrimination performance was tested in five adult mice using operant conditioning procedures with positive reinforcement. Mice were trained to nose poke to one hole during a repeating natural or synthetic USV, which would begin a trial. Subjects were required to poke to a second hole when they discriminated a change in the repeating background after a variable interval. The target stimuli were natural and synthetic versions of the same USVs, as well as other USVs. Mice can discriminate between some natural USVs and their synthetic renditions but not others. Discrimination performance across all stimuli was correlated with spectrotemporal similarity. Mice utilized duration, bandwidth, and peak frequency differently for natural and synthetic USV discrimination. These results contribute to our understanding of the ways USVs may be used for acoustic communication in mice. [This work was supported by NIDCD grant R01-DC012302 to MLD.]