J Cogn Neurosci. 1992 Winter;4(1):1-14. doi: 10.1162/jocn.1992.4.1.1.
During the last two decades there has been a proliferation of studies evaluating the psychophysical and neural attributes of heat-induced pain. Experiments using radiant and contact heat-induced pain have produced different observations thereby broadening our appreciation of the importance of acknowledging how a noxious heat stimulus is delivered; moreover manipulations of stimulus parameters have now provided a foundation for understanding the underlying neural mechanisms of heat-induced pain and their biological significance. The psychophysical attributes of heat-induced pain include highly reliable thresholds for most body regions, minimal adaptation to maintained noxious stimuli, an exquisite sensitivity to small changes in stimulus intensity, slow temporal summation for some types of heat-induced pain (i.e., second pain) but not for others (i.e., first pain), spatial summation---especially for suprathreshold noxious temperatures---and the perceived spread of pain well beyond the actual body area stimulated (i.e., radiation). The present body of information indicates that the pain system is optimally adapted for conveying precise information about intensity, and is less concerned with other stimulus features, such as spatial patterns or boundaries.
在过去的二十年中，评估热引起疼痛的心理物理学和神经属性的研究大量涌现。使用辐射和接触热引起疼痛的实验产生了不同的观察结果，从而扩大了我们对认识有害热刺激传递方式的重要性的认识；此外，刺激参数的操作现在为理解热引起疼痛的潜在神经机制及其生物学意义提供了基础。热引起疼痛的心理物理学属性包括大多数身体区域的高度可靠阈值，对持续有害刺激的最小适应，对刺激强度的微小变化的极高敏感性，对于某些类型的热引起疼痛（即第二疼痛）的缓慢时间总和，但对于其他类型（即第一疼痛）则没有，空间总和-特别是对于超阈值有害温度-以及感知到的疼痛范围远远超出实际刺激的身体区域（即辐射）。目前的信息表明，疼痛系统最适合传递有关强度的精确信息，而不太关注其他刺激特征，例如空间模式或边界。
