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Two experiments analyzed the role of extinction cues (EC) and stimuli associated to them in the reacquisition of conditioned ethanol tolerance. Ethanol-induced ataxia was measured in 80 rat subjects using a tilting plane, in a 5-phase procedure. The first experiment (which used 4 contexts and 40 rats) showed that the presentation of the extinction context by itself diminished the effectiveness of ECs in reducing response reacquisition. The second experiment (conducted in a single context with 40 rats and using 2 stimulus paired for some subjects or explicitly unpaired for others) showed that a secondary cue can reduce reacquisition, regardless of whether it was paired with the EC or not. The results of mixed and factor analyses of variance suggest that ECs affect response recovery through an association with the extinction context; however, a second-order cue associated to an EC appears to be unable to activate this association. [ABSTRACT FROM AUTHOR]

It has been reported that in certain phenomena (spontaneous recovery, reacquisition, resurgence and contextual renewal) it is possible to observe the recovery of a previously extinguished response. Contextual renewal refers to the reappearance of an extinguished response that result from a change of context between the extinction and testing phase. The purpose of the present study was to evaluate contextual renewal, considering both the temporal distribution of the responses and the response rate. A recovery of the response rate was found, being a result consistent with those reported in the area of contextual renewal. In addition, a renewal of the temporal distribution of the responses could be identified. The results are discussed by recognizing that rate and temporal distribution are two behavioral dimensions that are modulated by contextual changes. [ABSTRACT FROM AUTHOR]