Sniffing Out a Solution: Emotional Body Odors Can Improve Mindfulness Therapy for Social Anxiety Symptoms But Not for Depressive Symptoms

Abstract

Human body odors (BOs) have been shown to be an effective modality of social communication. Importantly, individuals exposed to emotional BOs report a partial reproduction of the affective state of the sender. Considering a need to improve existing therapeutic treatments, the present study investigated whether emotional human BOs could enhance the benefits of a mindfulness-based intervention. Individuals with social anxiety (SAD; n=48) or depression (DEP; n=30) were each randomly allocated to exposure to either happiness BO, fear BO, or clean air while performing two sessions of mindfulness. At the beginning and at the end of each day, affective symptoms were measured, and heart rate variability (HRV) and skin conductance level (SCL) were recorded during the intervention. Results showed a significant anxiety reduction on the second day for both happiness and fear conditions compared to clean air for SAD group. The HRV analysis showed that during the fear BO condition the HRV was lower compared to the clean air. No significant differences were found for SCL. Contrarily, BOs were found to have no beneficial effects for DEP group. These findings suggest that BOs may be used to support the positive outcomes of psychological therapy in individuals with social anxiety.

Note:
Funding declaration: This work was supported by the European Commission Horizon 2020 research and innovation program [grant number 824153] to the POTION project. C.C. was supported by a grant from MIUR [Dipartimenti di Eccellenza DM 11/05/2017 n. 262] to the Department of General Psychology.

Conflict of Interests: None

Ethical Approval: The present study was conducted with the adequate understanding and written informed consent in accordance with the Declaration of Helsinki and was approved by the local Ethics Committee, University of Padua (prot. no. 3667)

Trial Registration: ISRCTN Registry (No. 64408867)

Keywords: olfaction, human chemosignals, body odors, social anxiety, depression, mindfulness