The Anxiety-Reducing Effects of Alcohol Evaluated by Ultrasonic Vocalizations in Adult Female Mice
Discipline: Neuroscience
Session: 4
Room: 1 - Hanover DE
Nolan Lewis - Wesleyan University
Co-Author(s): Laverne Melón, Wesleyan University, Middletown, CT
Ultrasonic vocalizations (USVs) are believed to reflect arousal or emotional states in rodents, allowing for communication across members of the same species. In mice, sex informs frequency, generation, and influence of these 20-120 kHz calls. Calls emitted by female mice when interacting with the same sex include more “syllables,” units of sound interspersed with silence. When communicating with males for the purpose of mating, female calls have lower syllable variety. Recent work in rats suggests that features of USVs may be influenced by alcohol consumption. Our goal was to establish a method to evaluate USVs in mice in a variety of social settings to test the hypothesis that alcohol acutely impacts the frequency and generation of calls. Sober inbred C57BL/6J adult female mice were habituated to a reversed-12-hour light/dark cycle for one week, then transferred into a home built recording studio for 10 minutes (5 min acclimation, 5 minute recording). Mice were then placed into groups on a two-day drinking schedule. On day one, mice received either water or a 20% (v/v) ethanol solution in a modified drinking tube (2hrs of access at ZT3), and on day two all mice received ethanol (2hrs) before another recording session. Our data suggests that alcohol intake is associated with greater calls in higher frequencies that reflect positive affect and fewer low-frequency “aversive calls.” This class of calls promotes social interaction. When sober, mice experienced greater anxiety in the testing chamber, reflected by higher amplitude and incidence of lower frequency aversive calls and by the disordered pattern of their USVs. Future experiments will explore the intersection of lower syllable variation and sociability, the social effects of alcohol’s anxiety-reducing qualities, as well as sex differences in these behaviors.
Funder Acknowledgement(s): Wesleyan University is a proud recipient of the McNair Grant.
Faculty Advisor: Laverne Melón, lmelon@wesleyan.edu
Role: The entire project was conducted independently, including the written procedure, creation of the recording studio, placing mice on a drinking schedule, recording mice, and subsequent tests as well as audio analysis and generation of graphs.