Ach odorant. Furthermore, only one study [4] explored the olfactory abilities in MDE when more complex olfactory stimuli (mixture of odorants) were perceived. Indeed, most of the olfactory studies in mood disorders used single (pure) odorant compounds. This method is incongruent with daily life experiences where a subject experiences more complex olfactory stimuli. Thus, this study proposed an innovative method to investigate odor perception using complex olfactory stimuli. Indeed, we thought that this parameter would be very relevant to the understanding of olfactory impairments in depressed patients in more objective ways. Finally, to our Methyl linolenate site knowledge, few studies have evaluated the effects of the improvement of depressive symptoms on the olfactory abilities, and no study has investigated this aspect in a complex olfactory environment (odorant mixtures). Thus, evaluating the different olfactory parameters during a MDE 1326631 and after clinical improvement in response to antidepressant treatmentOlfactory Markers of Major Depressionwill allow us to determine whether the observed olfactory impairments are state- (disappearance of olfactory alterations in clinically improved patients) or trait-related (persistent olfactory alterations after clinical improvement). Indeed, according to Atanasova et al. (2008) [18], olfactory abnormalities might be a cognitive marker for psychiatric conditions, with a specific pattern for each disease. Thus, the aim of this pilot research was to determine the specific potential olfactory markers for depression by investigating several olfactory parameters during acute depressive phase and when patients were clinically improved. 18055761 The studied olfactory parameters were the odor identification (identification of single odors and identification of odors in binary iso-intense pleasant/unpleasant mixture), the odor intensity and discrimination evaluation, and the odor hedonic evaluation. We Octapressin hypothesized that depressed and/or clinically improved patients would have deficits in odor intensity and identification (of single odors), according to the hedonic valence of the stimuli, and that they would have difficulties discriminating different concentrations of pleasant stimuli when compared to controls. Concerning the hedonic evaluations, we hypothesized that depressed and/or clinically improved patients would perceive the pleasant odorants as less pleasant than controls, and the unpleasant odorants as more unpleasant. Lastly, concerning the identification of odors in binary mixture, we hypothesized that depressed and/or clinically improved patients would fail to identify the pleasant odorant compared with unpleasant one.and controls: U = 972.00, p,0.001; patients V2 and controls: U = 839.00, p,0.001). All patients received escitalopram at a flexible dose of 10?0 mg daily, but not necessarily as monotherapy. Indeed, benzodiazepine was administered for insomnia to 6 patients and beta-blocker was prescribed to 2 patients (for hypertension). No 
other psychotropic agents were used. Drug adherence was monitored and ensured by psychiatric nurses. Patients did not receive specific psychotherapy during their stay at hospital. Health controls had no personal or family history of any axis I disorder (MINI). They were drug-free and matched to cases on age, gender and smoking status in a ratio of 3:1. The characteristics of the groups are presented in Table 1.Experimental ProcedureThe experimental procedure was clearly explained to all partic.Ach odorant. Furthermore, only one study [4] 
explored the olfactory abilities in MDE when more complex olfactory stimuli (mixture of odorants) were perceived. Indeed, most of the olfactory studies in mood disorders used single (pure) odorant compounds. This method is incongruent with daily life experiences where a subject experiences more complex olfactory stimuli. Thus, this study proposed an innovative method to investigate odor perception using complex olfactory stimuli. Indeed, we thought that this parameter would be very relevant to the understanding of olfactory impairments in depressed patients in more objective ways. Finally, to our knowledge, few studies have evaluated the effects of the improvement of depressive symptoms on the olfactory abilities, and no study has investigated this aspect in a complex olfactory environment (odorant mixtures). Thus, evaluating the different olfactory parameters during a MDE 1326631 and after clinical improvement in response to antidepressant treatmentOlfactory Markers of Major Depressionwill allow us to determine whether the observed olfactory impairments are state- (disappearance of olfactory alterations in clinically improved patients) or trait-related (persistent olfactory alterations after clinical improvement). Indeed, according to Atanasova et al. (2008) [18], olfactory abnormalities might be a cognitive marker for psychiatric conditions, with a specific pattern for each disease. Thus, the aim of this pilot research was to determine the specific potential olfactory markers for depression by investigating several olfactory parameters during acute depressive phase and when patients were clinically improved. 18055761 The studied olfactory parameters were the odor identification (identification of single odors and identification of odors in binary iso-intense pleasant/unpleasant mixture), the odor intensity and discrimination evaluation, and the odor hedonic evaluation. We hypothesized that depressed and/or clinically improved patients would have deficits in odor intensity and identification (of single odors), according to the hedonic valence of the stimuli, and that they would have difficulties discriminating different concentrations of pleasant stimuli when compared to controls. Concerning the hedonic evaluations, we hypothesized that depressed and/or clinically improved patients would perceive the pleasant odorants as less pleasant than controls, and the unpleasant odorants as more unpleasant. Lastly, concerning the identification of odors in binary mixture, we hypothesized that depressed and/or clinically improved patients would fail to identify the pleasant odorant compared with unpleasant one.and controls: U = 972.00, p,0.001; patients V2 and controls: U = 839.00, p,0.001). All patients received escitalopram at a flexible dose of 10?0 mg daily, but not necessarily as monotherapy. Indeed, benzodiazepine was administered for insomnia to 6 patients and beta-blocker was prescribed to 2 patients (for hypertension). No other psychotropic agents were used. Drug adherence was monitored and ensured by psychiatric nurses. Patients did not receive specific psychotherapy during their stay at hospital. Health controls had no personal or family history of any axis I disorder (MINI). They were drug-free and matched to cases on age, gender and smoking status in a ratio of 3:1. The characteristics of the groups are presented in Table 1.Experimental ProcedureThe experimental procedure was clearly explained to all partic.
