Chronic pain disrupts the natural functional organization of the brain, particularly impacting default mode network nodes, insula, and top-down pain modulation circuits.
Meta-Analysis
Are there common resting-state fMRI brain alterations across different chronic pain pathologies compared to healthy controls?
Chronic pain is associated with common maladaptive brain plasticity across pathologies, particularly affecting the default mode network, insula, and descending pain modulation circuits.
Maladaptive brain plasticity has been reported in chronic pain (CP) conditions, though it remains unclear if there are common alterations across pathologies. Therefore, we systematically synthesized literature comparing resting-state functional magnetic resonance imaging (rs-fMRI) in CP patients and healthy controls (HC), and meta-analyzed data whenever applicable. Separate meta-analyses were performed for each method – (fractional) amplitude of low-frequency fluctuations (fALFF, ALFF), regional homogeneity (ReHo), seed-based connectivity (according to the seed) and independent component analysis (according to the network). In qualitative synthesis, sensory-discriminative pain processing – thalamus, insula, temporal and sensory cortices – and cognitive and emotional processing – cingulate, prefrontal and parietal cortices and precuneus – regions concentrated CP/HC differences. Meta-analyses revealed decreased ALFF and increased ReHo in the precuneus, increased fALFF in the left posterior insula and disrupted within- and cross-network connectivity of default mode network (DMN) nodes, as well as altered connectivity in top-down pain modulation pathways. Specifically, it showed decreased anterior and increased posterior components' representation within DMN, enhanced connectivity between the medial prefrontal cortex (mPFC, part of the DMN) and anterior insula (part of the salience network), and decreased mPFC connectivity with the periaqueductal gray matter (PAG). Collectively, results suggest that CP disrupts the natural functional organization of the brain, particularly impacting DMN nodes (mPFC and precuneus), insula and top-town pain modulation circuits. • Chronic pain manifests in multiple pathophysiological contexts. • Communalities across neurophysiological states helps diagnosis and therapeutics. • Chronic pain impacts in precuneus and insula resting-state activity (ALFF and ReHo). • Core DMN nodes presented abnormal connectivity within- and across-networks. • Decreased mPFC-PAG connectivity suggests altered descending pain modulation.
Fiúza-Fernandes et al. (Thu,) conducted a meta-analysis in Chronic pain. Chronic pain (exposure) vs. Healthy controls was evaluated on Resting-state functional magnetic resonance imaging (rs-fMRI) alterations (fALFF, ALFF, ReHo, connectivity). Chronic pain disrupts the natural functional organization of the brain, particularly impacting default mode network nodes, insula, and top-down pain modulation circuits.