title: Anticipatory 50 kHz ultrasonic vocalizations are associated with escalated alcohol intake in dependent rats.
abstract: Rats emit 50kHz ultrasonic vocalizations (USVs) in situations of increased motivation, such as during the anticipation of palatable food or drugs of abuse. Whether the same holds true for the anticipation of alcohol intake remains unknown. Alcohol drinking in a nondependent state is thought to be mediated by its rewarding effects (positive reinforcement), whereas drinking in the dependent state is motivated by alcohol's stress-relieving effects (negative reinforcement). Here, we measured context-elicited 50kHz USVs in alcohol-dependent (alcohol vapor-exposed) and nondependent rats immediately before operant alcohol self-administration sessions. Dependent rats showed escalated levels of alcohol intake compared with nondependent rats. Overall, dependent and nondependent rats showed similar levels of anticipatory 50kHz USVs. However, the number of anticipatory USVs was positively correlated with alcohol intake in dependent rats but not nondependent rats. Additionally, dependent rats with higher alcohol intake displayed increased anticipatory 50kHz USVs compared with rats that had lower alcohol intake, whereas no difference was observed between rats with high and low alcohol intake in the nondependent group. Increased 50kHz USVs were specific for the anticipation of alcohol self-administration and did not generalize to a novel environment. These findings suggest that anticipatory 50kHz USVs may be an indicator of context-elicited negative reinforcement learning.
authors.affiliation: Committee on the Neurobiology of Addictive Disorders, The Scripps Research Institute, La Jolla, CA, United States; Department of Psychology, University of California, San Diego, La Jolla, CA, United States. Electronic address: cbuck@ucsd.edu.
authors.forename: Cara L
authors.initials: CL
authors.lastname: Buck
authors.affiliation: Department of Psychology, University of California, San Diego, La Jolla, CA, United States.
authors.forename: Jordan C
authors.initials: JC
authors.lastname: Malavar
authors.affiliation: Committee on the Neurobiology of Addictive Disorders, The Scripps Research Institute, La Jolla, CA, United States.
authors.forename: Olivier
authors.initials: O
authors.lastname: George
authors.affiliation: Committee on the Neurobiology of Addictive Disorders, The Scripps Research Institute, La Jolla, CA, United States.
authors.forename: George F
authors.initials: GF
authors.lastname: Koob
authors.affiliation: Committee on the Neurobiology of Addictive Disorders, The Scripps Research Institute, La Jolla, CA, United States.
authors.forename: Leandro F
authors.initials: LF
authors.lastname: Vendruscolo
mesh_terms: D000428:Alcohol Drinking / Q000503:physiopathology*; D000437:Alcoholism / Q000503:physiopathology*; D000818:Animals; D000431:Ethanol / Q000506:poisoning*; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D012054:Reinforcement, Psychology; D012201:Reward; D012646:Self Administration; D013018:Sound Spectrography / Q000379:methods; D014465:Ultrasonics; D014828:Vocalization, Animal
chemical_list: D000431:Ethanol
keywords: Addiction; Alcoholism; Ethanol; Motivation; Reward; Ultrasonic vocalization