Differential neural correlates of oral capsaicin pleasantness in habitual and non-habitual spicy eaters
Year: 2025
Type: article
Abstract: • Habitual spicy eating is related to shift in hedonic but not intensity perception of oral capsaicin. • Habitual spicy eaters had greater left postcentral gyrus responses to high-concentration capsaicin. • Reduced right hippocampus activation to high-concentration capsaicin in habitual eaters. • Pleasantness for high-level capsaicin correlates positively with hippocampus activation in non-habitual eaters. • Altered hippocampus-somatosensory/affective connectivity in habitual eaters in response to low-concentration of capsaicin. Repeated exposure to spicy flavor can shift individuals’ preferences for capsaicin-containing stimuli, however, the neural mechanisms underlying the hedonic processing of oral capsaicin remain unclear. Here, we investigated how habitual spicy food consumption modulates brain responses involved in hedonic perceptions of oral capsaicin. Using functional magnetic resonance imaging, we compared brain activity between high-frequency (HF, N = 19) and low-frequency (LF, N = 17) spicy food consumers during oral administration of three concentrations of capsaicin (10 μM, 30 μM, 60 μM) and water as a control stimulus. Participants rated the pleasantness and intensity after each stimulus. Compared with the LF group, the HF group reported significantly higher pleasantness ratings across all capsaicin concentrations, an effect that was independent of perceived intensity. At the neural level, a significant group × concentration interaction was observed. For the high-concentration of capsaicin stimulation (60 μM), the HF group exhibited increased activation in the left postcentral gyrus and decreased activation in the right hippocampus relative to the LF group. In the LF group, pleasantness for the high concentration of capsaicin was positively correlated to activation in the right hippocampus. For the low-concentration of capsaicin (10 μM), the LF group showed weakened hippocampus–postcentral and hippocampus–caudate connectivity, but stronger insula–parahippocampal connectivity compared to the HF group. In addition, pleasantness ratings for low-concentration of capsaicin were positively correlated with hippocampus–postcentral connectivity in LF participants. Together, these findings suggest that the neural substrates subserving the hedonic processing of oral capsaicin vary as a function of habitual spicy food intake and stimulus concentration, reflecting experience-dependent plasticity within chemosensory and affective brain networks.
Source: NeuroImage
Authors: Luyi Zhou, Yihang Ma, Thomas Hummel, Pengfei Han
Language: English
Topic: Ion Channels and Receptors
Subfield: Sensory Systems
Field: Neuroscience
Domain: Life Sciences
Open Access status: gold
Estimated APC paid: $3,540
OpenAlex ID: W4416427830