Why are some odors perceived as pleasant while others are not? We review current research on how pleasant and unpleasant odors, that is, odors with positive or negative valence, are processed in the brain of flies and mice. We conclude that in mice pleasant and unpleasant odors are detected via three olfactory subsystems with only one being fully dedicated to unpleasant odors, while the others detect both good and bad odors. Correspondingly, so far no clear segmentation into regions processing exclusively pleasant or unpleasant odors has been identified in the mouse brain. The situation is different in flies, where most odors are sensed via the antenna. Already at the antennal lobe level, that is, the first processing center for olfactory input, odorants seem to be categorized as pleasant or unpleasant. We furthermore discuss why animals at all should make a decision based on olfaction, and why a straightforward and fast processing of odorant valence might be important for survival and reproduction.
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http://dx.doi.org/10.1016/j.conb.2013.08.010 | DOI Listing |
Neurosci Biobehav Rev
January 2025
Experimental Therapeutics and Pathophysiology Branch, National Institute of Mental Health, National Institutes of Health, Bethesda, MD, USA; Department of Psychiatry and Psychotherapy, Jena University Hospital, Jena, Germany. Electronic address:
Understanding how the brain distinguishes emotional from neutral scenes is crucial for advancing brain-computer interfaces, enabling real-time emotion detection for faster, more effective responses, and improving treatments for emotional disorders like depression and anxiety. However, inconsistent research findings have arisen from differences in study settings, such as variations in the time windows, brain regions, and emotion categories examined across studies. This review sought to compile the existing literature on the timing at which the adult brain differentiates basic affective from neutral scenes in less than one second, as previous studies have consistently shown that the brain can begin recognizing emotions within just a few milliseconds.
View Article and Find Full Text PDFNeuroimage
December 2024
Department of General Psychology, University of Padova, via Venezia 8, 35131 Padova, Italy; Padova Neuroscience Center, University of Padova, via Orus 2/B, 35129 Padova, Italy. Electronic address:
The impacting research on emotions of the last decades was carried out with different methods. The most popular was based on the use of a validated sample of slides, the International Affective Pictures System (IAPS), divided mainly into pleasant, neutral and unpleasant categories, and on fMRI as a measure of brain activation induced by these stimuli. With the present coordinate-based meta-analysis (CBMA) based on ALE approach, we aimed to unmask the main brain networks involved in the contrast of pleasant vs.
View Article and Find Full Text PDFJ Gerontol B Psychol Sci Soc Sci
December 2024
Institute for Social Research, University of Michigan, Ann Arbor, Michigan, USA.
Objectives: Limited research has explored caregivers' activities beyond caregiving duties, which may offer positive experiences and counterbalance caregiving stress. This study aimed to (a) identify the most pleasant non-caregiving activities, (b) assess time allocation based on activity categories and pleasantness, and (c) investigate the association between activity pleasantness and duration, considering differences between caregivers to older adults with Alzheimer's Disease and Related Dementias (ADRD) and those without.
Methods: This study included 2,136 caregivers (33% ADRD) from the 2017 National Study of Caregiving (NSOC) who participated in a time diary interview.
Neurobiol Stress
November 2024
Department of Biological Psychology and Affective Science, Faculty of Human Sciences, University of Potsdam, Potsdam, Germany.
Eur Neuropsychopharmacol
November 2024
Neurocognition and Emotion in Affective Disorders (NEAD) Centre, Psychiatric Centre Copenhagen, Frederiksberg Hospital, Copenhagen, Denmark; Department of Psychology, University of Copenhagen, Denmark. Electronic address:
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