title: Rivalry of homeostatic and sensory-evoked emotions: Dehydration attenuates olfactory disgust and its neural correlates.
abstract: Neural correlates have been described for emotions evoked by states of homeostatic imbalance (e.g. thirst, hunger, and breathlessness) and for emotions induced by external sensory stimulation (such as fear and disgust). However, the neurobiological mechanisms of their interaction, when they are experienced simultaneously, are still unknown. We investigated the interaction on the neurobiological and the perceptional level using subjective ratings, serum parameters, and functional magnetic resonance imaging (fMRI) in a situation of emotional rivalry, when both a homeostatic and a sensory-evoked emotion were experienced at the same time. Twenty highly dehydrated male subjects rated a disgusting odor as significantly less repulsive when they were thirsty. On the neurobiological level, we found that this reduction in subjective disgust during thirst was accompanied by a significantly reduced neural activity in the insular cortex, a brain area known to be considerably involved in processing of disgust. Furthermore, during the experience of disgust in the satiated condition, we observed a significant functional connectivity between brain areas responding to the disgusting odor, which was absent during the stimulation in the thirsty condition. These results suggest interference of conflicting emotions: an acute homeostatic imbalance can attenuate the experience of another emotion evoked by the sensory perception of a potentially harmful external agent. This finding offers novel insights with regard to the behavioral relevance of biologically different types of emotions, indicating that some types of emotions are more imperative for behavior than others. As a general principle, this modulatory effect during the conflict of homeostatic and sensory-evoked emotions may function to safeguard survival.
authors.affiliation: Division of Systems Neuroscience of Psychopathology, Translational Research Center, University Hospital of Psychiatry, University of Bern, Bolligenstrasse 111, CH-3000 Bern 60, Switzerland.
authors.forename: Lea
authors.initials: L
authors.lastname: Meier
authors.affiliation: Rhinology, Smell and Taste Outpatient Clinic, Department of Otorhinolaryngology Head and Neck Surgery, Bern University Hospital, Inselspital, Freiburgstrasse, CH-3010 Bern, Switzerland.
authors.forename: Hergen
authors.initials: H
authors.lastname: Friedrich
authors.affiliation: Psychiatric Neuroimaging Unit, Translational Research Center, University Hospital of Psychiatry, University of Bern, Bolligenstrasse 111, CH-3000 Bern 60, Switzerland.
authors.forename: Andrea
authors.initials: A
authors.lastname: Federspiel
authors.affiliation: Psychiatric Neuroimaging Unit, Translational Research Center, University Hospital of Psychiatry, University of Bern, Bolligenstrasse 111, CH-3000 Bern 60, Switzerland; Ahmanson-Lovelace Brain Mapping Center, Department of Neurology, University of California Los Angeles, 90095 Los Angeles, CA, USA.
authors.forename: Kay
authors.initials: K
authors.lastname: Jann
authors.affiliation: Division of Systems Neuroscience of Psychopathology, Translational Research Center, University Hospital of Psychiatry, University of Bern, Bolligenstrasse 111, CH-3000 Bern 60, Switzerland; Japan Science and Technology Agency, PRESTO, 4-1-8 Honcho Kawaguchi, Saitama 332-0012, Japan.
authors.forename: Yosuke
authors.initials: Y
authors.lastname: Morishima
authors.affiliation: Rhinology, Smell and Taste Outpatient Clinic, Department of Otorhinolaryngology Head and Neck Surgery, Bern University Hospital, Inselspital, Freiburgstrasse, CH-3010 Bern, Switzerland; Rhinology-Olfactology Unit, Department of Otorhinolaryngology, Geneva Neuroscience Center (CMU), University of Geneva Hospitals, Rue Gabrielle-Perret-Gentil 4, CH-1211 Geneva 14, Switzerland.
authors.forename: Basile Nicolas
authors.initials: BN
authors.lastname: Landis
authors.affiliation: Institute of Diagnostic and Interventional Neuroradiology, Inselspital, University of Bern, Freiburgstrasse, CH-3010 Bern, Switzerland.
authors.forename: Roland
authors.initials: R
authors.lastname: Wiest
authors.affiliation: Division of Systems Neuroscience of Psychopathology, Translational Research Center, University Hospital of Psychiatry, University of Bern, Bolligenstrasse 111, CH-3000 Bern 60, Switzerland.
authors.forename: Werner
authors.initials: W
authors.lastname: Strik
authors.affiliation: Division of Systems Neuroscience of Psychopathology, Translational Research Center, University Hospital of Psychiatry, University of Bern, Bolligenstrasse 111, CH-3000 Bern 60, Switzerland. Electronic address: dierks@puk.unibe.ch.
authors.forename: Thomas
authors.initials: T
authors.lastname: Dierks
mesh_terms: D000328:Adult; D000339:Affect / Q000502:physiology; D001921:Brain / Q000502:physiology; D001931:Brain Mapping; D002540:Cerebral Cortex / Q000502:physiology*; D003681:Dehydration / Q000503:physiopathology*; D004644:Emotions / Q000502:physiology*; D006706:Homeostasis; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D009812:Odorants; D055696:Olfactory Perception / Q000502:physiology*; D055815:Young Adult
keywords: Disgust; Functional MRI; Insular cortex; Olfaction; Thirst