Data from: Food vibrations: Asian spice sets lips trembling

Szechuan pepper, a widely used ingredient in the cuisine of many Asian countries, is known for the tingling sensation it induces on the tongue and lips. While the molecular mechanism by which Szechuan pepper activates tactile afferent fibres has been clarified, the tingling sensation itself has been less studied, and it remains unclear which fibres are responsible. We investigated the somatosensory perception of tingling in humans to identify the characteristic temporal frequency and compare this to the established selectivity of tactile afferents. Szechuan pepper was applied to the lower lip of participants. Participants judged the frequency of the tingling sensation on the lips by comparing this with the frequencies of mechanical vibrations applied to their right index finger. The perceived frequency of the tingling was consistently at around 50 Hz, corresponding to the range of tactile RA1 afferent fibres. Furthermore, adaptation of the RA1 channel by prolonged mechanical vibration reliably reduced the tingling frequency induced by Szechuan pepper, confirming that the frequency-specific tactile channel is shared between Szechuan pepper and mechanical vibration. Combining information about molecular reactions at peripheral receptors with quantitative psychophysical measurement may provide a unique method for characterizing unusual experiences by decomposing them into identifiable minimal units of sensation.花椒（Szechuan pepper）是诸多亚洲国家料理中广泛应用的食材，其可于舌部与唇部引发麻刺感，该特性广为人知。尽管花椒激活触觉传入纤维的分子机制已被阐明，但麻刺感本身的相关研究仍较为匮乏，目前仍未明确其具体由哪类纤维介导。本研究针对人体的麻刺感体感感知展开探究，旨在明确其特征性时间频率，并将该频率与已明确的触觉传入纤维的选择性特征进行对比。实验中将花椒施用于受试者下唇，受试者通过将唇部麻刺感的频率与施加于右手食指的机械振动频率进行比对，来判断唇部麻刺感的频率。结果显示，受试者感知到的麻刺频率始终维持在约50Hz，这与RA1触觉传入纤维（RA1 afferent fibres）的频率响应范围相符。此外，通过长时间机械振动使RA1通道发生适应后，花椒诱导的麻刺频率显著降低，这证实了花椒与机械振动共享具有频率特异性的触觉通道。将外周受体的分子反应信息与定量心理物理学测量相结合，或可提供一种独特的研究方法：通过将异常感官体验分解为可识别的最小感觉单元，实现对其的特征化分析。