Ultrasonic Vocalizations by Adult Rats (Rattus norvegicus).

摘要

The literature on adult rat (Rattus norvegicus) ultrasonic vocalizations was reviewed. Most of these studies examined ultrasounds produced during sexual behavior and during male-male aggressive interactions. During sexual behavior, both the male and female emit a 22-30 kHz, 500-3,000 ms call (the '22-kHz call). This call is particularly characteristic of male vocalizations immediately following ejaculation. Both sexes also produce higher frequency (40-70 kHz), shorter duration calls. The male's postejaculatory 22-kHz call has not been demonstrated to influence female behavior; however, the presence of male vocalizations prior to ejaculation is related to an increase in female proceptive behavior. During aggressive encounters, the submissive male produces a 22-kHz call similar to that seen during sexual behavior, as well as other calls of higher frequency. The communicative functions of these calls have not yet been established. The 22-kHz call is also produced by rats following shock and in response to startle-eliciting acoustic stimuli. Because the call occurs in these contexts, it has been suggested that it indicates anxiety or distress. The published literature on adult rat ultrasound has been limited to studies of pairs of unfamiliar animals in artificial testing situations. Few quantitative data on the acoustic characteristics of these calls have been published.