Chemosensory danger detection in the human brain: Body odor communicating aggression modulates limbic system activation. (May 2017)

• Record Type: Journal Article
• Authors: Mutic, Smiljana; Brünner, Yvonne F.; Rodriguez-Raecke, Rea; Wiesmann, Martin; Freiherr, Jessica
• Is Part Of: Neuropsychologia. Volume 99(2017)
• Page Start: 187
• Page End: 198
• Publication Date: 2017-05
• Subjects: Chemosensation -- Chemosignal -- Olfaction -- Anger -- Threat; Neuropsychology -- Periodicals; Neurology -- Periodicals; Psychophysiology -- Periodicals; Neuropsychologie -- Périodiques; Neuropsychology; Periodicals; Electronic journals; 616.8
• DOI: 10.1016/j.neuropsychologia.2017.02.018
• Languages: English
• ISSNs: 0028-3932

Abstract

Abstract: Although the sense of smell is involved in numerous survival functions, the processing of body odor emitted by dangerous individuals is far from understood. The aim of the study was to explore how human fight chemosignals communicating aggression can alter brain activation related to an attentional bias and danger detection. While the anterior cingulate cortex (ACC) was seen involved in processing threat-related emotional information, danger detection and error evaluation, it still remains unknown whether human chemosignals communicating aggression can potentially modulate this activation. In the fMRI experiment, healthy male and female normosmic odor recipients (n=18) completed a higher-order processing task (emotional Stroop task with the word categories anger, anxiety, happiness and neutral) while exposed to aggression and exercise chemosignals (collected from a different group of healthy male donors; n=16). Our results provide first evidence that aggression chemosignals induce a time-sensitive attentional bias in chemosensory danger detection and modulate limbic system activation. During exposure to aggression chemosignals compared to exercise chemosignals, functional imaging data indicates an enhancement of thalamus, hypothalamus and insula activation (p<.05, FWE-corrected). Together with the thalamus, the ACC was seen activated in response to threat-related words (p<.001). Chemosensory priming and habituation to body odor signals are discussed. Highlights: We investigated chemosensory danger detection in human body odors via fMRI. RT to aggression chemosignals depends on stimulus novelty and odor habituation. Threat-predicting body odor of combative donors alters brain activity in recipients. Aggression chemosignals are preferentially processed in the limbic system. Chemosensory danger detection is associated with neural alarm system activation.