Altered amygdala-prefrontal connectivity in chronic nonspecific low back pain: resting-state fMRI and dynamic causal modelling study

Objective: Recent advances in brain imaging have deepened our knowledge of the neural activity in distinct brain areas associated with acupuncture analgesia. However, there has not been conclusive research into the frequency-specific resting-state functional changes associated with acupuncture analgesia in patients with chronic pain. Here, we aimed to characterize changes across multiple frequencies of resting-state cortical activity associated with ankle acupuncture stimulation (AAS) in patients with chronic low back pain (CLBP) and healthy controls.Methods: Twenty seven patients with CLBP and Twenty five age- and gender-matched healthy volunteers were enrolled in the study. Participants received tactile sham acupuncture (TSA) and AAS, respectively. The whole-brain amplitude of low-frequency fluctuation (ALFF) in the range 0.01–0.25 Hz was assessed for changes associated with each intervention. Further, a visual analog scale (VAS) was used to collect subjective measures of pain intensity in patients. Linear mixed-effect modeling (LME) was used to examine the mean ALFF values of AAS and TSA between patients and healthy controls.Results: The ALFF was modulated in the default mode network (an increase in the medial prefrontal cortex, and a decrease in the cerebellum/posterior ingulate/parahippocampus, P < 0.01, corrected) in both patients and controls. Decreased ALFF in the bilateral insular was frequency-dependent. Modulations in the cerebellum and right insular were significantly correlated with VAS pain score after AAS (P < 0.01).Conclusion: Hence, frequency-specific resting-state activity in the cerebellum and insular was correlated to AAS analgesia. Our frequency-specific analysis of ALFF may provide novel insights related to pain relief from acupuncture.

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Examining resting-state functional connectivity in key hubs of the default mode network in chronic low back pain

Scandinavian Journal of Pain ◽

10.1515/sjpain-2020-0184 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

Sin Ki Ng ◽

Donna M. Urquhart ◽

Paul B. Fitzgerald ◽

Flavia M. Cicuttini ◽

Melissa Kirkovski ◽

...

Keyword(s):

Low Back Pain ◽

Back Pain ◽

Functional Connectivity ◽

Default Mode Network ◽

Chronic Low Back Pain ◽

Resting State ◽

Angular Gyrus ◽

Healthy Controls ◽

Low Back ◽

Default Mode

Abstract Objectives Changes in brain connectivity have been observed within the default mode network (DMN) in chronic low back pain (CLBP), however the extent of these disruptions and how they may be related to CLBP requires further examination. While studies using seed-based analysis have found disrupted functional connectivity in the medial prefrontal cortex (mPFC), a major hub of the DMN, limited studies have investigated other equally important hubs, such as the posterior cingulate cortex (PCC) in CLBP. Methods This preliminary study comprised 12 individuals with CLBP and 12 healthy controls who completed a resting-state functional magnetic resonance imaging (fMRI) scan. The mPFC and PCC were used as seeds to assess functional connectivity. Results Both groups displayed similar patterns of DMN connectivity, however group comparisons showed that CLBP group had reduced connectivity between the PCC and angular gyrus compared to healthy controls. An exploratory analysis examined whether the alterations observed in mPFC and PCC connectivity were related to pain catastrophizing in CLBP, but no significant associations were observed. Conclusions These results may suggest alterations in the PCC are apparent in CLBP, however, the impact and functional role of these disruptions require further investigation.

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Resting-State Functional Connectivity of the Sensorimotor Network in Individuals with Nonspecific Low Back Pain and the Association with the Sit-to-Stand-to-Sit Task

Brain Connectivity ◽

10.1089/brain.2014.0309 ◽

2015 ◽

Vol 5 (5) ◽

pp. 303-311 ◽

Cited By ~ 32

Author(s):

Madelon Pijnenburg ◽

Simon Brumagne ◽

Karen Caeyenberghs ◽

Lotte Janssens ◽

Nina Goossens ◽

...

Keyword(s):

Low Back Pain ◽

Back Pain ◽

Functional Connectivity ◽

Resting State ◽

Low Back ◽

Resting State Functional Connectivity ◽

Sensorimotor Network ◽

Sit To Stand

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Brain Network Response to Acupuncture Stimuli in Experimental Acute Low Back Pain: An fMRI Study

Evidence-based Complementary and Alternative Medicine ◽

10.1155/2015/210120 ◽

2015 ◽

Vol 2015 ◽

pp. 1-13 ◽

Cited By ~ 14

Author(s):

Yu Shi ◽

Ziping Liu ◽

Shanshan Zhang ◽

Qiang Li ◽

Shigui Guo ◽

...

Keyword(s):

Low Back Pain ◽

Back Pain ◽

Limbic System ◽

Resting State Fmri ◽

Brain Network ◽

Low Back ◽

Acupuncture Analgesia ◽

Acute Low Back Pain ◽

Pain Status ◽

Pain State

Most neuroimaging studies have demonstrated that acupuncture can significantly modulate brain activation patterns in healthy subjects, while only a few studies have examined clinical pain. In the current study, we combined an experimental acute low back pain (ALBP) model and functional magnetic resonance imaging (fMRI) to explore the neural mechanisms of acupuncture analgesia. All ALBP subjects first underwent two resting state fMRI scans at baseline and during a painful episode and then underwent two additional fMRI scans, once during acupuncture stimulation (ACUP) and once during tactile stimulation (SHAM) pseudorandomly, at the BL40 acupoint. Our results showed that, compared with the baseline, the pain state had higher regional homogeneity (ReHo) values in the pain matrix, limbic system, and default mode network (DMN) and lower ReHo values in frontal gyrus and temporal gyrus; compared with the OFF status, ACUP yielded broad deactivation in subjects, including nearly all of the limbic system, pain status, and DMN, and also evoked numerous activations in the attentional and somatosensory systems; compared with SHAM, we found that ACUP induced more deactivations and fewer activations in the subjects. Multiple brain networks play crucial roles in acupuncture analgesia, suggesting that ACUP exceeds a somatosensory-guided mind-body therapy for ALBP.

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