Olfactory Training and Emotional State

Study Overview
=================
Brief Summary
-----------------
During the past three decades, researchers have paid particular attention to the study of olfactory disorders in depression. Recent studies have shown that depression is characterized by a change in olfactory and emotional perception resulting in a decrease of the perception of positive stimuli (odors and facial expressions) and an increase in perception of negative stimuli (odors). Moreover, it has also been shown in healthy subjects that the presence of minor depressive symptoms leads to a decreasing of olfactory sensitivity. However, odor discrimination was not impaired in these subjects. This observation suggest the presence of a change in targeted olfactory perception in people with depressive symptoms without reporting major depression. In addition, studies in subjects with olfactory disorders (following respiratory tract infections or following Parkinson's disease) have shown an improvement in olfactory function after daily training with odors during 12 weeks. From all these observations, the hypothesis is that an olfactory training could improve the overall olfactory functioning and the emotional perception of the subjects presenting minor depressive symptoms and of the depressed patients.

Detailed Description
-----------------
Recent studies have shown that depression is characterized by a change in olfactory and emotional perception resulting in a decrease of the perception of positive stimuli (odors and facial expressions) and an increase in perception of negative stimuli (odors). Moreover, it has also been shown in healthy subjects that the presence of minor depressive symptoms leads to a decreasing of olfactory sensitivity. However, odor discrimination was not impaired in these subjects. This observation suggest the presence of a change in targeted olfactory perception in people with depressive symptoms without reporting major depression. In addition, studies in subjects with olfactory disorders (following respiratory tract infections or following Parkinson's disease) have shown an improvement in olfactory function after daily training with odors during 12 weeks. Therefore, the hypothesis is that an olfactory training could improve the overall olfactory functioning and the emotional perception of the subjects presenting minor depressive symptoms and of the depressed patients. The main objective is to study the effect of daily olfactory training on the emotional state and emotional perception of the subject. The effect of the training will be evaluated using three types of evaluations: (1) a clinical evaluation and the psychometric scales, (2) the investigation of the olfactory function and (3) the study of the emotional perception. The secondary objectives are: The identification of olfactory parameters and emotional valences associated with minor depressive symptoms. The study of the link between the subjective and objective emotional response on the one hand, and the link between olfactory function, emotional perception and emotional state on the other hand in depressed patients and in individuals with minor depressive symptoms.

Official Title
-----------------
Olfactory Training and Emotional State

Conditions
-----------------
Depressive Symptoms, Depressive Disorder, Major

Intervention / Treatment
-----------------
* Other: Sensory training


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria healthy subjects: Without psychiatric history QIDS scale score less than or equal to 15 Affiliation to a social security system Able to give his written informed consent Inclusion Criteria depressed patients: With a diagnosis of depressive episode characterized according to the DSM-5 criteria, confirmed by the Mini International Neuropsychiatric Interview (MINI) No argument for bipolar disorder or schizophrenia, confirmed by the MINI QIDS scale score greater than or equal to 16 Follow-up in hospitalization and / or ambulatory consultation Without comorbidities (alcoholism, eating disorders ...) Affiliation to a social security system Able to give his written informed consent Exclusion Criteria healthy subjects and depressed patients: Pathology or condition likely to modify their olfactory and / or taste perception Allergies with one or more odors, food allergies and / or known anosmias and ageusia Legal incapacity and / or circumstances rendering the person incapable of understanding the nature, objectives or consequences of the study

Ages Eligible for Study
-----------------
Minimum Age: 18 Years
Maximum Age: 65 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
Accepts Healthy Volunteers

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Other
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Other: Sensory training<br>Sensory (Olfactory or visual) training will be done at home for 12 weeks. The effect of the training will be evaluated using an experimental protocol includes (i) clinical and psychometric evaluations, (ii) the study of olfactory perception using Sniffin' Sticks Test and (iii) the study of the emotional perception using the subjective Sense'n Feel method and the objective measurement of the spontaneous pupillary dilatation. | Other: Sensory training<br>* 12 weeks sensory training<br>* Other names: Olfactory or visual training;|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change from Baseline Olfactory Perception at 3 months | Score obtained with the Sniffin 'Stick test | Baseline (T0), a month and a half (T1.5), 3 months (T3) | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Emotional perception measured Sense'n Feel Method | Score obtained with Sense'n Feel Method | Baseline (T0), a month and a half (T1.5), 3 months (T3) | 
| Emotional perception measured with SMI RED-m Scientific device | Observation of spontaneous pupillary dilatation with SMI RED-m Scientific device | Baseline (T0), a month and a half (T1.5), 3 months (T3) | 
| Psychometric scale MINI : Psychiatric disorders exploration | Mini International Neuropsychiatric Interview | Baseline (T0), a month and a half (T1.5), 3 months (T3) | 
| Psychometric scale TAS-20 : alexithymia assessment | Twenty-item toronto Alexithymia Scale (TAS-20) | Baseline (T0), a month and a half (T1.5), 3 months (T3) | 
| Psychometric scale STAI-Y : anxiety assessment | State Trait Anxiety Inventory | Baseline (T0), a month and a half (T1.5), 3 months (T3) | 
| Psychometric scale SHAPS : anhedonia assessment | The Snaith-Hamilton Pleasure Scale | Baseline (T0), a month and a half (T1.5), 3 months (T3) | 
| Psychometric scale QIDS-SR16 : Depression assessment | Quick Inventory of Depressive Symptomatology | Baseline (T0), a month and a half (T1.5), 3 months (T3) | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
Sensory training, Depression, Olfaction, Emotion, Perception