"Addicted" rats? Epistemic challenges in modeling addiction with laboratory animals

In contemporary biology laboratories, animal models have become essential scientific tools. From modeling psychiatric disorders to investigating embryonic development and genetic diseases, they facilitate research across various fields. Although scientists are generally cautious about extrapolating results from these models, this paper introduces a thought-provoking case study-the three-criteria addiction model-which boldly endeavors to induce "full addiction" in laboratory rats. Given the model's influence in the field of behavioral neuroscience, this paper aims to conduct its comprehensive epistemic analysis, exploring whether "addicted rats" genuinely exist and the potential implications for understanding addiction and mental disorders. Conducting such an epistemic analysis presents a difficulty in itself due to the heterogeneity of approaches employed by philosophers of science to analyze animal models. The second objective of this paper is, therefore, to propose a general method to guide epistemic scrutiny of animal models.