Extrapolation from Animal Model of Depressive Disorders: What’s Lost in Translation?

Abstract

Animal models of depression are problematic and results drawn from them is moderately convincing. The main problem, it is often argued, is that it is impossible to model a mental disorder, i.e. specifically human, in animals like rodents: it is a matter of resemblance of symptoms. Yet in this field it is generally assumed that animal models of depression are more or less ‘valid’ according to three criteria: predictive, construct, and face validity, with only the latter concerned with the resemblance of symptoms. It is argued here that the problem is actually not with resemblance to the clinical features or to the factors of depression: it is not their being mental parameters. It lies, rather, in the fuzziness of the definition of a human entity and in the difficulty of linking together supposedly involved biological mechanisms into a consistent picture of the underlying process of the disease. It is therefore not that we cannot model what we know to be depression, it is rather that we do not know what to model.