PDF(Pubmed)
Abstract：
UNASSIGNED: Temporal summation (TS) of pain occurs when pain increases over repeated presentations of identical noxious stimuli. TS paradigms can model central sensitization, a state of hyperexcitability in nociceptive pathways that promotes chronic pain onset and maintenance. Many experimenters use painful heat stimuli to measure TS (TS-heat); yet, TS-heat research faces unresolved challenges, including difficulty evoking summation in up to 30-50% of participants. Moreover, substantial variability exists between laboratories regarding the methods for evoking and calculating TS-heat.
UNASSIGNED: To address these limitations, this study sought to identify optimal parameters for evoking TS-heat in healthy participants with a commercially available constant contact heat stimulator, the Medoc TSA-II. Working within constraints of the TSA-II, stimulus trains with varying parameters (eg, stimulus frequency, baseline temp, peak temp, peak duration, testing site) were tested in a sample of 32 healthy, chronic pain-free participants to determine which combination best evoked TS-heat. To determine whether TS scoring method altered results, TS-heat was scored using three common methods.
UNASSIGNED: Across all methods, only two trains successfully evoked group-level TS-heat. These trains shared the following parameters: site (palmar hand), baseline and peak temperatures (44°C and 50°C, respectively), and peak duration (0.5 s). Both produced summation that peaked at moderate pain (~50 out of 100 rating).
UNASSIGNED: Future TS-heat investigations using constant contact thermodes and fixed protocols may benefit from adopting stimulus parameters that include testing on the palmar hand, using 44°C baseline and 50°C peak temperatures, at ≥0.33 Hz stimulus frequency, and peak pulse durations of at least 0.5 seconds.
UNASSIGNED: To address these limitations, this study sought to identify optimal parameters for evoking TS-heat in healthy participants with a commercially available constant contact heat stimulator, the Medoc TSA-II. Working within constraints of the TSA-II, stimulus trains with varying parameters (eg, stimulus frequency, baseline temp, peak temp, peak duration, testing site) were tested in a sample of 32 healthy, chronic pain-free participants to determine which combination best evoked TS-heat. To determine whether TS scoring method altered results, TS-heat was scored using three common methods.
UNASSIGNED: Across all methods, only two trains successfully evoked group-level TS-heat. These trains shared the following parameters: site (palmar hand), baseline and peak temperatures (44°C and 50°C, respectively), and peak duration (0.5 s). Both produced summation that peaked at moderate pain (~50 out of 100 rating).
UNASSIGNED: Future TS-heat investigations using constant contact thermodes and fixed protocols may benefit from adopting stimulus parameters that include testing on the palmar hand, using 44°C baseline and 50°C peak temperatures, at ≥0.33 Hz stimulus frequency, and peak pulse durations of at least 0.5 seconds.
摘要：
■当疼痛在重复呈现相同的有害刺激后增加时,发生疼痛的时间求和(TS)。TS范式可以对中心敏化进行建模，一种促进慢性疼痛发作和维持的伤害性途径的过度兴奋状态。许多实验者使用痛苦的热刺激来测量TS(TS-heat)；然而，TS热研究面临尚未解决的挑战，包括高达30-50%的参与者难以唤起总结。此外，在激发和计算TS热量的方法方面，实验室之间存在很大的差异。
■为了解决这些限制，这项研究试图确定最佳参数，以唤起TS-热在健康参与者与市售的恒定接触热刺激器，MedocTSA-II.在TSA-II的限制范围内工作，具有不同参数的刺激列车(例如，刺激频率,基线温度,峰值温度,峰值持续时间,测试站点)在32个健康样本中进行了测试，慢性无痛参与者，以确定哪种组合最好地诱发TS热。为了确定TS评分方法是否改变了结果，使用三种常用方法对TS-热量进行评分。
■在所有方法中，只有两列火车成功引发了群体性TS-heat。这些列车共享以下参数：站点（手掌），基线和峰值温度（44°C和50°C，分别)，和峰值持续时间（0.5s）。两者都产生了在中度疼痛时达到峰值的总和（100级中的〜50级）。
■使用恒定的接触温度计和固定协议的未来TS热研究可能会受益于采用刺激参数，包括在手掌上进行测试，使用44°C基线和50°C峰值温度，在≥0.33Hz刺激频率下，和至少0.5秒的峰值脉冲持续时间。
■为了解决这些限制，这项研究试图确定最佳参数，以唤起TS-热在健康参与者与市售的恒定接触热刺激器，MedocTSA-II.在TSA-II的限制范围内工作，具有不同参数的刺激列车(例如，刺激频率,基线温度,峰值温度,峰值持续时间,测试站点)在32个健康样本中进行了测试，慢性无痛参与者，以确定哪种组合最好地诱发TS热。为了确定TS评分方法是否改变了结果，使用三种常用方法对TS-热量进行评分。
■在所有方法中，只有两列火车成功引发了群体性TS-heat。这些列车共享以下参数：站点（手掌），基线和峰值温度（44°C和50°C，分别)，和峰值持续时间（0.5s）。两者都产生了在中度疼痛时达到峰值的总和（100级中的〜50级）。
■使用恒定的接触温度计和固定协议的未来TS热研究可能会受益于采用刺激参数，包括在手掌上进行测试，使用44°C基线和50°C峰值温度，在≥0.33Hz刺激频率下，和至少0.5秒的峰值脉冲持续时间。
