Does exposure to body odors increase the effect of mindfulness treatment in patients with social anxiety symptoms?

INTERVENTION: This procedure was already described in the pre‐registration of a preliminary study (registration number: ISRCTN64408867) conducted within the same project (POTION project, serial number 824153). Given the exploratory nature and the results of the preliminary study, the current study has been developed with a larger sample size and refined design. Study design: Patients will be screened using the Liebowitz Social Anxiety Scale, the Patient Health Questionnaire, and the Structured Clinical Interview for DSM‐5. Only female patients will be recruited. On the first day of the study, all patients will be asked to complete a demographic questionnaire, the State‐Trait Anxiety Inventory (STAI) and one question to assess if the participant has experience with mindfulness meditation. After completing the baseline questionnaires, the participants will be randomly allocated to an odor group (happiness, fear, neutral or clean air) and start a treatment intervention consisting of mindfulness meditation (more details below). The odors are previously collected from healthy volunteers (see section below). During the intervention, they will be exposed to the odor corresponding to the group to which they have been randomized, while their electrodermal activity and heart rate is measured. Following the intervention, the STAI will be assessed once more. In total, the trial day 1 should last approximately 60 minutes. The next day, all subjects will perform the same trial as day one: first completing the STAI questionnaire at baseline, then the mindfulness meditation intervention while being exposed to the same odor as they were exposed to the previous day, then completing the STAI questionnai CONDITION: Social anxiety symptoms ; Mental and Behavioural Disorders PRIMARY OUTCOME: Anxiety symptoms measured by the State‐Trait Anxiety Inventory (STAI) at baseline, at the end of day 1, at the beginning of day 2, after mindfulness intervention at day 2, after stress induction and during day 3 INCLUSION CRITERIA: 1. Aged between 18 and 35 years 2. Female gender 3. A score over 50 on the Liebowitz Social Anxiety Scale in its self‐report formulation (LSAS‐SR) 4. A confirmation of the disorder during a face‐to‐face interview 5. Normosmic as screened with Sniffin’ Stick test 6. No pregnancy 7. Non‐smokers SECONDARY OUTCOME: ; 1. Awareness of social odors measured using the Social Odor Scale (SOS) at baseline during day 1; 2. Heart rate variability measured using ECG at baseline, during treatment and post‐treatment of day 1; at baseline, during treatment, post‐treatment and post‐stress induction of day 2.; 3. Skin conductance measured using electrodermal activity (EDA) at baseline, during treatment and post‐treatment of day 1; at baseline, during treatment, post‐treatment and post‐stress induction of day 2; 4. Previous experience with mindfulness meditation (answering the question “Do you practice or have you ever practiced mindfulness meditation?”, if yes there is a follow‐up question “how often do you practice?” with possible answers “not currently”, “practice less than one time a week”, “less than three times a week”, “practice three times a week or more”, “practice every day”) measured at baseline during day 1; 5. State mindfulness assessed with the State Mindfulness Scale (SMS) at post‐treatment during day 2; 6. Manipulation check of anxiety induction (after stress induction): Social anxiety; Task‐related anxiety; Task importance. Done after the stress induction during day 2; 7. Perceived helpfulness of the intervention (0 to 10 rating scale from “not useful at all” to “very useful”) measured after the stress induction on day 2; 8. Intensity, pleasantness and familiarity of the odor (each one on a scale from 1 to 10 from “not at all” to “very much”) measured after the stress induction on day 2; 9. Number of drop‐outs in each odor group measured at the follow‐up online session during day 3;