Acupuncture & Meridian Science Research Center, College of Korean Medicine, Kyung Hee University, Seoul, Republic of Korea.
KM Fundamental Research Division, Korea Institute of Oriental Medicine, Daejeon, Republic of Korea.
Neuroimage Clin. 2018 Jun 20;19:982-989. doi: 10.1016/j.nicl.2018.06.022. eCollection 2018.
The brain actively interprets sensory inputs by integrating top-down and bottom-up information. Humans can make inferences on somatosensation based on prior experiences and expectations even without the actual stimulation. We used functional magnetic resonance imaging to investigate the neural substrates of the expectations of the sensory experience of cutaneous electrical stimulation on acupoint without actual stimuli. This study included 22 participants who wore sticker-type electrodes attached on three different acupoints on different body regions: CV17 (chest), CV23 (chin), and left PC6 (arm). Participants evaluated sensations after they expected electrical stimulation on those points in random order without actual stimulation. All stimuli were presented with corresponding visual information of the stimulation sites. The control condition included the same visual information but outside the body. The expectations of cutaneous electrical stimuli without actual stimulation on three acupoints resulted in greater sensation compared to the control condition. Cognitive components of cutaneous electrical stimulation exhibited greater brain activation in the anterior insula, pre-supplementary motor area, and secondary somatosensory area. The expectations of acupuncture stimulation exhibited a distinct experience of somatosensation as well as brain activations in insula and pre-supplementary motor area. Our findings suggest that the sensory experience of the pseudo-cutaneous stimulation may be derived from the predictive role of the salience network in monitoring internal and external body states.
大脑通过整合自上而下和自下而上的信息来主动解释感觉输入。即使没有实际刺激，人类也可以基于先前的经验和期望对手部感觉进行推断。我们使用功能磁共振成像来研究在没有实际刺激的情况下，穴位皮肤电刺激感觉体验的期望的神经基础。这项研究包括 22 名参与者，他们在身体不同部位的三个不同穴位上佩戴了贴纸式电极：CV17（胸部）、CV23（下巴）和左侧 PC6（手臂）。参与者在没有实际刺激的情况下，随机顺序预期这些部位的电刺激后评估感觉。所有刺激都伴随着刺激部位的相应视觉信息。对照条件包括相同的视觉信息，但在身体外部。与对照条件相比，三个穴位的皮肤电刺激没有实际刺激的期望会导致更大的感觉。皮肤电刺激的认知成分在前脑岛、辅助运动前区和次级体感区表现出更大的大脑激活。针刺刺激的期望表现出一种独特的感觉体验，以及脑岛和辅助运动前区的大脑激活。我们的发现表明，伪皮肤刺激的感觉体验可能来自于突显网络在监测内部和外部身体状态中的预测作用。
