Conspecific-Associated Ultrasonic Vocalizations Modulate Resource-Directed Exploratory Behavior in Rats.

BACKGROUND

Social acoustic cues can influence behavioral decisions in rodents, but whether conspecific-associated ultrasonic vocalizations (USVs) contribute to resource-directed exploratory behavior across a physical barrier remains unclear.

METHODS

We established a sucrose-capsaicin dual-choice paradigm and compared behavioral and acoustic measures between rats exploring alone and rats exploring in the presence of a pre-exposed conspecific confined within the central enclosure. Drinking bout counts, zone occupancy, locomotor trajectories, and USV characteristics were quantified. USV playback and broadband white-noise masking were subsequently used to examine the contribution of acoustic signals to the observed behavioral changes.

RESULTS

The presence of a pre-exposed conspecific significantly reduced sucrose drinking bout counts and time spent in the sucrose-associated zone, accompanied by a redistribution of spatial exploration. The two experimental conditions also differed in USV acoustic features and call-type composition. Playback of USVs recorded under the Conspecific condition reproduced key changes in resource-directed exploration, whereas broadband white-noise masking attenuated the behavioral effects associated with conspecific presence.

CONCLUSION

Conspecific-associated USVs contribute to the modulation of resource-directed exploratory behavior across a physical barrier. These findings provide a behavioral framework for investigating how social acoustic information influences resource exploration and spatial allocation in rats.