Characterization of an alcohol addiction-prone phenotype in mice

Human studies indicate that high impulsivity, novelty seeking and anxiety predispose individuals to alcohol abuse. Unclear, however, is whether the same phenotypes can be observed in laboratory animals prone to uncontrolled alcohol drinking. To characterize a novelty-seeking trait, anxiety, impulsivity, compulsivity and the motivation for natural rewards in mice, numerous tests were performed in the automated IntelliCage learning system. The same mice then had extended access to alcohol for 70 days, followed by the evaluation of addiction-like behaviors, including (1) the motivation for alcohol in a progressive-ratio schedule of reinforcement; (2) persistent and compulsive alcohol seeking and taking during signaled 'no alcohol' periods and (3) when subjected to punishment; and (4) the intensity of relapse after alcohol withdrawal. Our data suggest that high levels of anxiety-related traits (i.e. low novelty seeking, low resistance to punishment and a high level of compulsive behaviors) and high impulsivity predict addiction-like alcohol drinking in mice. Future studies are, however, warranted to create a valid model of alcohol addiction in mice in the IntelliCage system.