Differences in olfactory perception in patients with schizophrenia and affective spectrum disorders

Abstract

The measurement of olfactory sensitivity has emerged as a significant and informative area of research, considering its potential involvement in regulating human emotions and behavior through the anatomical and functional connections between olfactory structures and the limbic system. Olfactory deficits have been linked to disturbances in the emotional and personality domains, and their interrelationship with negative and productive symptoms across various mental disorders has been explored. This study aimed to examine the olfactory function in patients diagnosed with schizophrenia spectrum disorders (SSD) and depressive disorders as well as its association with the current emotional state. A total of 158 participants were included, comprising individuals with SSD (n = 66), depressive disorders (n = 29), and a control group without psychiatric pathology (n = 63). Results revealed a significant reduction in odor recognition ability among patients with SSD compared to both the control group and patients with depressive disorders. Noteworthy variations were observed in the identification of specific odorants across the three groups. Furthermore, associations were found between the ability to identify odors and components of the emotional-personality sphere in control group and patients with depressive disorders, while no such relationship was observed among patients with SSD. Nonetheless, within the SSD group, impairments in perceiving specific odorants were correlated with indicators of current emotional states and empathy processes. Our findings have implications for the development of additional differential diagnostics in clinical psychology and psychiatry.