You See What You Smell: Preferential Processing of Chemosensory Satiety Cues and Its Impact on Body Shape Perception

• Published in: Brain sciences Vol. 11; no. 9; p. 1152
• Main Authors: Pause, Bettina M., Schäfer, Annika S., Hoenen, Matthias, Lübke, Katrin T., Stockhorst, Ursula
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 30.08.2021; MDPI
• Subjects: Alcohol; BMI; Body mass index; body odors; Body weight; Chemoreception; Cotton; Diet; EEG; Event-related potentials; Fasting; Females; Food; Food quality; Fruits; Human influences; Hunger; Information processing; Males; Metabolic disorders; metabolic state; Odors; Overweight; Participation; Satiety; Temporal gyrus; Underweight; Veganism; Vegetarianism; Visual evoked potentials; Visual perception; Volatiles; Womens health; Germany
• ISSN: 2076-3425; 2076-3425
• DOI: 10.3390/brainsci11091152

The current study examines neural responses to satiety- and fasting-related volatiles and their effect on the processing of body shapes. Axillary sweat was sampled with cotton pads from 10 individuals after 12 h of fasting, and after having consumed a standard breakfast. Pure cotton pads served as the control. The chemosensory stimuli were presented to 20 participants (via a constant-flow olfactometer) exclusively, and additionally as context to images of overweight and underweight avatars. EEG was recorded (61 electrodes), and chemosensory (CSERPs; P1, N1, P2, P3) and visual event-related potentials (VERPs; N1, P2, P3a, P3b) were analyzed. The amplitudes of all positive CSERP components differed more strongly from cotton in response to chemosensory satiety cues as compared to fasting cues (P1: p = 0.023, P2: p = 0.083, P3: p = 0.031), paralleled by activity within the middle frontal and temporal gyrus. Overweight compared to underweight body shapes tended to elicit larger VERP P2 amplitudes (p = 0.068), and chemosensory satiety cues amplified the VERP amplitudes in response to any body shape (P2, P3a, P3b; all ps ≤ 0.017) as compared to the cotton control. The results indicate that chemosensory satiety cues transmit complex social information, overriding the processing of analogous visual input.