Search

Much is known about the effect of odors on mood, cognition and behavior, but little is known about the relationship between odors and well-being. We investigated the neural processing of odors with different degrees of association with well-being (WB) through two large independent datasets. The study encompassed pre-testing and fMRI. During pre-testing, 100 and 80 (studies 1 and 2) young, healthy subjects participated, rating intensity, valence, and WB association for 14 (study 1) and 8 (study 2) different odors. Pre-testing resulted in the selection of two odors with high WB association (WB-associated) and two odors with lower WB association (neutral odors) for each study. Odors were delivered intranasally to the subjects who underwent fMRI scanning (44 and 41 subjects, respectively, for studies 1 and 2). We assessed brain activity for subjects when they experienced WB-associated versus neutral odors. In study 1, WB-associated odors showed increased activation in the right angular gyrus whereas in study 2, increased activity in the left angular gyrus existed, together with increased activity in the anterior cingulate cortex and posterior orbitofrontal cortex. The increased activity of higher-order cognitive and emotional regions during the processing of WB-associated odors in the two independent studies suggests a role of odors in influencing individual well-being. Moreover, the consistent activation of the angular gyrus might suggest its key role in shifting attention toward relevant emotional stimuli. [ABSTRACT FROM AUTHOR]

Introduction: Patients with chemosensory dysfunction frequently report symptoms of depression. The current study aims to clarify whether the type (smell dysfunction, taste dysfunction, and mixed smell and taste dysfunction), severity, duration, or cause of dysfunction have differential impacts on the symptoms of depression.Methods: 899 patients with chemosensory disorders and 62 controls were included. Following a structured interview and an otorhinolaryngological examination, subjects underwent olfactory tests (Sniffin' Sticks), gustatory tests (taste sprays) and an assessment of depressive symptoms (Beck Depression Inventory). Information on the cause and duration of disorders was also collected.Results: Patients with combined olfactory/gustatory dysfunction had higher depression scores than patients with smell dysfunction only and controls, and no significant difference was found between the smell dysfunction and controls. Anosmia patients, but not hyposmia patients, exhibited higher depression scores than controls. Among various causes of chemosensory disorders, patients from the posttraumatic group had higher depression scores than patients with other causes of chemosensory dysfunction (sinonasal, idiopathic, or postinfectious). Multiple linear regression analyses suggested that reduced olfactory function was associated with enhanced depression scores in the olfactory disorders group (B = -0.326, t = -2.294, and p = 0.02) and in all patients with chemosensory disorders (B = -0.374, t = -2.550, p = 0.017).Discussion/conclusion: Simultaneously decreased input of olfaction and gustation seems to have an additive effect on the exacerbation of emotional dysfunction. Early intervention should be considered for depression symptoms in patients with mixed olfactory/gustatory dysfunction in clinical practice. [ABSTRACT FROM AUTHOR]