Department of Chiropractic, Université du Québec à Trois-Rivières, Trois-Rivières, QC, Canada.
CogNAC Research Group, Université du Québec à Trois-Rivières, Trois-Rivières, QC, Canada.
Pain. 2019 Mar;160(3):724-733. doi: 10.1097/j.pain.0000000000001451.
Integration of nociceptive information is essential to produce adapted responses, to promote body integrity and survival. However, how the brain integrates nociceptive inputs from different body areas remains unknown. The aim of this study was to examine the cortical integration of bilateral nociceptive inputs evoked by laser heat stimuli. Sixteen healthy volunteers (8 F, 8 M; age: 25.5 ± 4.3) were recruited to participate in one session during which painful laser stimuli were applied to their hands with 2 Nd:YAP laser systems. Electroencephalographic activity was recorded to measure laser-evoked potentials and event-related spectral perturbations. Twenty nociceptive stimuli were applied in each of the 4 counterbalanced conditions: (1) right hand, (2) left hand, and both hands with (3) attention to the right or (4) attention to the left. Compared with unilateral conditions, N2 and P2 peak amplitude as well as gamma oscillation power were decreased in bilateral conditions (P < 0.05), but these effects were not affected by the direction of attention (P > 0.1). By contrast, pain was not significantly different in any condition (P > 0.05). These findings show that although more nociceptive inputs reach the brain with multiple nociceptive stimuli, their sensory representation is decreased while pain perception remains unchanged. These interactions between cerebral processing of nociceptive information from different body regions could support coordinated behavioral responses when pain origins from multiple sources.
整合伤害性信息对于产生适应性反应、促进身体完整性和生存至关重要。然而，大脑如何整合来自不同身体区域的伤害性输入仍然未知。本研究旨在研究由激光热刺激引起的双侧伤害性输入的皮层整合。招募了 16 名健康志愿者（8 名女性，8 名男性；年龄：25.5±4.3）参加了一个实验，在此期间，用 2 个 Nd：YAP 激光系统将疼痛激光刺激应用于他们的手部。记录脑电图活动以测量激光诱发电位和事件相关频谱扰动。在 4 种平衡条件下，每种条件下应用 20 个疼痛刺激：（1）右手，（2）左手，（3）注意右手或（4）注意左手时的双手。与单侧条件相比，双侧条件下 N2 和 P2 峰值幅度以及伽马振荡功率降低（P <0.05），但这些效应不受注意方向的影响（P >0.1）。相比之下，任何条件下的疼痛均无显著差异（P >0.05）。这些发现表明，尽管多个疼痛刺激会向大脑输送更多的伤害性输入，但它们的感觉表示减少，而疼痛感知保持不变。这些来自不同身体区域的伤害性信息在大脑中的相互作用可能支持来自多个来源的疼痛时协调的行为反应。
