Cognitive and affective models of psychedelics in rodents

In recent years, public and academic interest into psychedelics has increased, given the clinical evidence of their potential benefits for treating psychiatric conditions such as major depressive disorder (MDD). While this has been accompanied by several landmark human studies, mechanistic studies in rodents are still relatively few, but such studies are crucial for understanding the neurobiological underpinnings of the therapeutic effects of psychedelics. However, findings from rodent studies will only be of benefit to patients if they achieve translational validity. In this chapter, we will critically appraise rodent assays traditionally used to study cognition and affect, summarising existing findings with psychedelics. We will also highlight novel, translationally valid assays that have already been used or could be used in the future to study these drugs. We argue that the adoption of translational assays is critical for the interpretation of animal studies of psychedelic effects on cognition and affect. We also discuss how these studies have the potential to help unravel the mechanisms which contribute to their therapeutic effects but only if they involve relevant doses.