Social Transmission of Ethanol Preference in a Sign-Tracking Paradigm

The Observer/ Demonstrator Effect suggests that rats can socially obtain preferences for novel foods/drugs by interacting with experienced conspecifics. Sign-tracking is a paradigm which uses a conditioning procedure to evoke compulsive-like behaviors directed towards a tangible conditioned stimulus (CS) paired with a motivating unconditioned stimulus (US). The present study investigated the possibility that increased alcohol use results from the combination of socially transmitted cues and the kind of conditioning effect seen in sign-tracking procedures. Therefore, it was hypothesized that social exposure to an alcohol-experienced conspecific would summate with the conditioning experience and increase the sign-tracking of a bottle CS containing alcoholic beer. Subjects were exposed to social cues via conspecifics who consumed alcoholic- (AOG) or non-alcoholic beer (NAOG). Both groups experienced a sign-tracking procedure with alcoholic beer as the CS and a sugar pellet US. Sign- and goal-tracking were measured as licks on the bottle CS and nose pokes into the food receptacle US, respectively. The results showed no differences in sign tracking between groups across conditioning days. Preference tests outside of the conditioning paradigm indicated the social transmission was successful, as the AOG drank significantly more alcoholic beer than the NAOG. However, this difference between groups was not maintained once sign-tracking began. The hypothesis could not be supported as the two main groups, AOG and NAOG, did not behave differently during sign-tracking