Dysfunctions of the emotion processing circuitry are associated with Major Depressive Disorder (MDD) and can be modulated by antidepressants like selective serotonin reuptake inhibitors (SSRIs). Moreover, motivation, pleasure or interest are important neuropsychological states of emotional life, and are known to be impaired in MDD patients. Under SSRIs, some patients report decreases in motivation and/or in emotional responsiveness commonly described as emotional detachment (Corruble E et al, 2013) and having significant impact on drug compliance and quality of life.

The antidepressant agomelatine displays a unique neurochemical profile, different from SSRIs, being a MT1/MT2 receptors agonist and a 5HT2C receptors antagonist (De Bodinat C et al, 2010). Data from healthy volunteers and patients suggest that agomelatine is associated with less emotional detachment as compared to SSRIs notably with a more specific action in the facial expression recognition task (Harmer CJ et al, 2011), lower scores on scales for blunting (Corruble E et al, 2013), and absence of sexual dysfunction (Montejo AL et al, 2010).

Here, the effects of two antidepressants, agomelatine (25 and 50mg) and escitalopram (10–20mg) on emotional detachment, emotional processing, motivation and sexual function were assessed during a 9-week randomised, double-blind, placebo-controlled, parallel-designed study in healthy male and female volunteers aged between 18-45 years. A battery of neuropsychological and motivation tasks/questionnaires available in the literature were used. Investigating antidepressant effects on key psychological processes in healthy volunteers allows elucidation of the direct actions of antidepressants unconfounded by changes in mood symptoms. The study is on progress.