Study on the underlying brain mechanism of fabric-evoked prickling sensation based on fMRI

Prickling is one of the crucial determinants of textile comfort. Existing research indicates that prickling is a composite perception integrating the sensory modalities of pain and itch. However, the underlying functional mechanisms of the brain have not been fully explained. In this study, the technology of functional magnetic resonance imaging (fMRI) was employed to investigate the brain functional responses elicited by fabrics with different prickling levels. Ten healthy participants were recruited and exposed to tactile stimulation from the three fabrics, Fabric A (wool, high prickling), Fabric B (wool, medium prickling), and Fabric C (cotton, low prickling). A task-based fMRI design was adopted to analyze the correlations between brain functional signals and subjective ratings from the participants. The results demonstrated that fabric-evoked prickling engaged a distributed neural network including the insula cortex (IC), anterior cingulate cortex (ACC), postcentral gyrus (PoCG), amygdala (Amy), and frontal lobe (FL) regions. The anterior insula, a key hub for pain processing, showed markedly stronger activation (Fabric B: z = 7.71) than the posterior insula associated with itch (Fabric B: z = 3.13), whereas activation in itch-specific regions such as the precuneus (Prec) was relatively weak. Moreover, activation intensities in the ACC and PoCG were consistent with subjective prickling ratings. These findings indicate that fabric-evoked prickling predominantly arises from synergistic activation of pain- and itch-related regions, with pain-associated areas playing a dominant role, thereby providing novel insight into the neural mechanism of fabric-induced discomfort and offering a potential method for characterizing fabric-evoked prickle.