Preservation of within-compound associations after blocked preexposure to two compound flavors

•Within-compound associations are established between two flavors presented together.•These associations are not extinguished after blocked preexposure to two compound flavors.•We examine recent evidences supporting this conclusion.

Three experiments investigated the extinction of the within-compound A ↔ X association established when two compound flavors, AX and BX, are preexposed in blocks (i.e., AX, AX, AX, ... BX, BX, BX). In Experiment 1, a group of rats received preexposure to a block of AX trials followed by a second block of BX trials (AX–BX), while a second group received blocked preexposure to the same stimuli in the opposite order (BX–AX). Subsequently, flavor A was paired with lithium chloride. This conditioning resulted in a similar reduction of consumption of flavor X in both groups. In Experiment 2 four groups of rats received blocked preexposure to AX–BX, AX–B, A–BX, or A–X. After aversive conditioning of X, consumption of A and B was significantly lower for the groups which received these flavors paired with X than for the groups for which these flavors were presented isolated. In Experiment 3 a group of rats was preexposed to a block of SaltX presentations followed by a block of BX presentations (SaltX–BX), and a second group received blocked preexposure to (BX–SaltX). After subsequent sodium depletion, consumption of X was high and similar for the SaltX–BX and for the BX–SaltX groups. These results indicate that the within-compound association established in the first block of a blocked preexposure is not extinguished when the preexposure phase is concluded.