Burke, C. J., Kisko, T. M., Swiftwolfe, H. et al. 2017. Specific 50-kHz vocalizations are tightly linked to particular types of behavior in juvenile rats anticipating play. PLOS ONE 12(5), e0175841.
Rat ultrasonic vocalizations have been suggested to be either a byproduct of physical movement or, in the case of 50-kHz calls, a means to communicate positive affect. Yet there are up to 14 distinct types...