Playback of Alarm and Appetitive Calls Differentially Impacts Vocal, Heart-Rate, and Motor Response in Rats

Krzysztof H Olszyński; Rafał Polowy; Monika Małż; Paweł M Boguszewski; Robert K Filipkowski

doi:10.1016/j.isci.2020.101577

Playback of Alarm and Appetitive Calls Differentially Impacts Vocal, Heart-Rate, and Motor Response in Rats

iScience. 2020 Sep 19;23(10):101577. doi: 10.1016/j.isci.2020.101577. eCollection 2020 Oct 23.

Authors

Krzysztof H Olszyński¹, Rafał Polowy¹, Monika Małż¹, Paweł M Boguszewski², Robert K Filipkowski¹

Affiliations

¹ Behavior and Metabolism Research Laboratory, Mossakowski Medical Research Centre, Polish Academy of Sciences, 5 Pawinskiego St, 02-106 Warsaw, Poland.
² Laboratory of Animal Models, Nencki Institute of Experimental Biology, Polish Academy of Sciences, 3 Pasteur St, 02-093 Warsaw, Poland.

Abstract

Our rudimentary knowledge about rat intraspecific vocal system of information exchange is limited by experimental models of communication. Rats emit 50-kHz ultrasonic vocalizations in appetitive states and 22-kHz ones in aversive states. Both affective states influence heart rate. We propose a behavioral model employing exposure to pre-recorded playbacks in home-cage-like conditions. Fifty-kHz playbacks elicited the most vocalizations (>60 calls per minute, mostly of 50-kHz type), increased heart rate, and locomotor activity. In contrast, 22-kHz playback led to abrupt decrease in heart rate and locomotor activity. Observed effects were more pronounced in singly housed rats compared with the paired housed group; they were stronger when evoked by natural playback than by corresponding artificial tones. Finally, we also observed correlations between the number of vocalizations, heart rate levels, and locomotor activity. The correlations were especially strong in response to 50-kHz playback.

Keywords: Animals; Biological Sciences; Ethology.