Dopamine induces an optimism bias in rats-Pharmacological proof for the translational validity of the ambiguous-cue interpretation test

This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy).This article has been retracted at the request of the authors.Shortly after the above paper was published in Behavioural Brain Research, the authors discovered errors in the dataset they had analysed. After re-analysing a corrected dataset, they did not find the same results as in their publication. In contrast, they found that chronic treatment with L-DOPA did not significantly change cognitive judgement bias in rats (Figure 5). Erroneous data appeared also in Figure 3, showing the effects of acute administration of haloperidol on cognitive judgment bias in rats.The first author, graduate student Jakub Kregiel, who collected the data, took full responsibility for these errors.Consequently, the authors do not feel that the main result of their publication is valid. The authors are deeply regretful for any scientific misconceptions that may have resulted from this publication and would like to apologise to the readers, reviewers and editors of Behavioural Brain Research.All co-authors agree to this statement.