title: Resting-state connectivity in the default mode network and insula during experimental low back pain.
abstract: Functional magnetic resonance imaging studies have shown that the insular cortex has a significant role in pain identification and information integration, while the default mode network is associated with cognitive and memory-related aspects of pain perception. However, changes in the functional connectivity between the default mode network and insula during pain remain unclear. This study used 3.0 T functional magnetic resonance imaging scans in 12 healthy subjects aged 24.8 ± 3.3 years to compare the differences in the functional activity and connectivity of the insula and default mode network between the baseline and pain condition induced by intramuscular injection of hypertonic saline. Compared with the baseline, the insula was more functionally connected with the medial prefrontal and lateral temporal cortices, whereas there was lower connectivity with the posterior cingulate cortex, precuneus and inferior parietal lobule in the pain condition. In addition, compared with baseline, the anterior cingulate cortex exhibited greater connectivity with the posterior insula, but lower connectivity with the anterior insula, during the pain condition. These data indicate that experimental low back pain led to dysfunction in the connectivity between the insula and default mode network resulting from an impairment of the regions of the brain related to cognition and emotion, suggesting the importance of the interaction between these regions in pain processing.
authors.affiliation: Department of Rehabilitation Medicine, Zhujiang Hospital, Southern Medical University, Guangzhou, Guangdong Province, China.
authors.forename: Shanshan
authors.initials: S
authors.lastname: Zhang
authors.affiliation: Department of Rehabilitation Medicine, Zhujiang Hospital, Southern Medical University, Guangzhou, Guangdong Province, China.
authors.forename: Wen
authors.initials: W
authors.lastname: Wu
authors.affiliation: Department of Rehabilitation Medicine, Zhujiang Hospital, Southern Medical University, Guangzhou, Guangdong Province, China.
authors.forename: Guozhi
authors.initials: G
authors.lastname: Huang
authors.affiliation: Department of Rehabilitation Medicine, Zhujiang Hospital, Southern Medical University, Guangzhou, Guangdong Province, China.
authors.forename: Ziping
authors.initials: Z
authors.lastname: Liu
authors.affiliation: Department of Rehabilitation Medicine, Zhujiang Hospital, Southern Medical University, Guangzhou, Guangdong Province, China.
authors.forename: Shigui
authors.initials: S
authors.lastname: Guo
authors.affiliation: Department of Radiology, Zhujiang Hospital, Southern Medical University, Guangzhou, Guangdong Province, China.
authors.forename: Jianming
authors.initials: J
authors.lastname: Yang
authors.affiliation: Department of Rehabilitation Medicine, Zhujiang Hospital, Southern Medical University, Guangzhou, Guangdong Province, China.
authors.forename: Kangling
authors.initials: K
authors.lastname: Wang
keywords: cognitive; default mode network; emotion; functional connectivity; functional magnetic resonance imaging; hypertonic saline; insula; low back pain; nerve regeneration; neural regeneration; resting-state; the Science and Technology Foundation of Guangdong Province of China; visual analogue scale