The Impact of Translational Neuroscience on Revisiting Psychiatric Diagnosis: State of the Art and Conceptual Analysis

Once upon a time there was a psychiatric community believing in the "bible" of psychiatry (the DSM, Diagnostic and Statistical Manual of Mental Disorders). There were rigorous operational criteria functioning as mechanisms in which the input was the symptoms found by the clinician and the output a diagnostic label. Such diagnoses, called mental disorders, were assumed to be natural entities like many other medical diseases, the only problem being that their aetiopathogenesis was still unknown. However, there was a general trust that with time researchers would have discovered the specific genetic liabilities, neurochemical imbalances and neurocognitive circuits responsible for mental disorders. Many were surprised to realise that the long awaited DSM-5 (1) was published in the midst of unusual controversy, with the credibility of the "bible" being put in question. For example, the former president of the World Psychiatric Association, Maj (2), commented that since the publication of the DSM-IV: "Only a couple of decades have passed, but those already seem "good This paper reviews translational research in psychiatry, focusing on those programs addressing the problem of the validity of psychiatric diagnoses. In medicine in general, and in psychiatry in particular, the term "translational" is used with different meanings. A conceptual analysis suggests that there are at least seven different types of translational research in psychiatry: T1 ("benchto-bedside" development of tools and treatments), T2 (application of animal models to human psychiatry), T3 (papers focusing on the mind-brain gap, studying biological, neurobiological and cognitive dysfunctions), T4 (personalised therapies and prediction of treatment responses), T5 ("bedside-to-bench" translation of population data for laboratories), T6 (implementation of treatments at the population level, including accessibility and quality of services), and T7 (improving translational knowledge in residents' trainings and researchers' careers).