Animal models in psychiatry: Conceptualization and preclinical models of depression

Resumen

Psychiatric diseases in general and mood disorders in particular, are difficult to model in animals since the subjective nature of the core symptoms appears to preclude objective observation of behavioural changes. A suitable animal model of a psychiatric condition must fulfil three core criteria: share patho-physiological characteristics withthe human disease (face validity); measure accurately the behavioural and biochemical manifestations of the disease (construct validity); and symptoms improve with medications that improve those seen in afflicted humans (predictive validity). Also, it is well known that genetic and environmental factors play a key role in psychiatric disorders. Genetic animal models of these disorders represent an important direction for research, and are widely used to explore the role of different genes in brain mechanisms. In this review we explore the conceptualization of animal models in psychiatry and their extension to the different animal models of depression in particular. Conclusions: Animal models are necessary for the advancement of knowledge of the neurobiological mechanisms underlying psychiatric disorders. They are also very useful for exploring new therapeutic alternatives. However, a correct interpretation and conceptualization of a particular state in animals is essential for them to be considered animal models of a human illness. A model should be a useful system for studying another system, not simply a reduction or a simplification.