title: Rats concatenate 22 kHz and 50 kHz calls into a single utterance.
abstract: Traditionally, the ultrasonic vocal repertoire of rats is differentiated into 22 kHz and 50 kHz calls, two categories that contain multiple different call types. Although both categories have different functions, they are sometimes produced in the same behavioral context. Here, we investigated the peripheral mechanisms that generate sequences of calls from both categories. Male rats, either sexually experienced or naïve, were exposed to an estrous female. The majority of sexually naïve male rats produced 22 kHz and 50 kHz calls on their first encounter with a female. We recorded subglottal pressure and electromyographic activity of laryngeal muscles and found that male rats sometimes concatenate long 22 kHz calls and 50 kHz trill calls into an utterance produced during a single breath. The qualitatively different laryngeal motor patterns for both call types were produced serially during the same breathing cycle. The finding demonstrates flexibility in the laryngeal-respiratory coordination during ultrasonic vocal production, which has not been previously documented physiologically in non-human mammals. Since only naïve males produced the 22 kHz-trills, it is possible that the production is experience dependent.
authors.affiliation: College of Veterinary Medicine, Midwestern University, 19555 N 59th Ave, Glendale, AZ 85308, USA.
authors.forename: Christine
authors.initials: C
authors.lastname: Hernandez
authors.affiliation: Arizona College of Osteopathic Medicine, Midwestern University, 19555 N 59th Ave, Glendale, AZ 85308, USA.
authors.forename: Mark
authors.initials: M
authors.lastname: Sabin
authors.affiliation: College of Veterinary Medicine, Midwestern University, 19555 N 59th Ave, Glendale, AZ 85308, USA triede@midwestern.edu.|Arizona College of Osteopathic Medicine, Midwestern University, 19555 N 59th Ave, Glendale, AZ 85308, USA.|Department of Physiology, Midwestern University, 19555 N 59th Ave, Glendale, AZ 85308, USA.
authors.forename: Tobias
authors.identifier: 0000-0001-6875-0017
authors.initials: T
authors.lastname: Riede
mesh_terms: D000161:Acoustic Stimulation; D000818:Animals; D005260:Female; D007830:Larynx / Q000502:physiology; D008297:Male; D051381:Rats / Q000502:physiology*; D012119:Respiration; D012726:Sexual Behavior, Animal; D013018:Sound Spectrography; D000069453:Ultrasonic Waves; D014828:Vocalization, Animal
keywords: Larynx and breath control; Ultrasonic vocalizations (USVs); Vocal combinatorial capacity; Vocal production