Institute of Neuroscience and Physiology, University of Gothenburg, Gothenburg, Sweden.
Department of Radiation Physics at the Institute of Clinical Sciences, University of Gothenburg, Gothenburg, Sweden; Department of Medical Physics and Biomedical Engineering, Sahlgrenska University Hospital, Gothenburg, Sweden.
Dev Cogn Neurosci. 2019 Feb;35:94-103. doi: 10.1016/j.dcn.2017.12.006. Epub 2017 Dec 22.
The insula is important for the processing of pleasant aspects of touch whereas its role in the processing of emotionally neutral touch has been less explored. Here, we used a network approach to investigate the insular processing of pleasant stroking touch and emotionally neutral vibratory touch, analysing functional magnetic resonance imaging data from 23 healthy adult participants. Vibration and skin stroking activated areas in the posterior, middle and anterior insula. Psychophysiological interaction analyses suggested that skin stroking increased functional connectivity between the posterior and ventral anterior insula. Vibration instead increased functional connectivity between the posterior and dorsal anterior insula, and induced a stronger decrease of the default mode network activity compared to stroking. These results confirmed findings from previous studies showing that the posterior insula processes affective touch information. We suggest that this is accomplished by relaying tactile information from the posterior insula to ventral anterior insula, an area tightly connected to the emotional parts of the brain. However, our results also suggested that the insula processes tactile information with less emotional valence. A central hub in this processing seemed to be the right dorsal anterior insula.
脑岛对于处理触觉的愉悦方面很重要，但其在处理情感中性触觉方面的作用则较少被探索。在这里，我们使用网络方法来研究愉悦的轻抚触摸和情感中性的振动触摸对脑岛的处理，分析了 23 名健康成年参与者的功能磁共振成像数据。振动和皮肤轻抚激活了后、中、前脑岛的区域。心理生理交互分析表明，皮肤轻抚增加了后脑岛和腹侧前脑岛之间的功能连接。相比之下，振动增加了后脑岛和背侧前脑岛之间的功能连接，并与轻抚相比，诱导默认模式网络活动的下降更强。这些结果证实了之前研究的发现，即后脑岛处理情感性触觉信息。我们认为，这是通过将触觉信息从前脑岛传递到与大脑情感部分紧密相连的腹侧前脑岛来完成的。然而，我们的结果还表明，脑岛处理触觉信息的情感效价较低。这个处理过程的一个中心枢纽似乎是右侧背侧前脑岛。
