Chronic pain-induced functional and structural alterations in the brain: A multi-modal meta-analysis

Area of Science:

• Neuroscience
• Radiology
• Medical Imaging

Background:

• Chronic pain is a widespread condition linked to significant brain alterations.
• Existing neuroimaging studies show variability, necessitating a comprehensive multi-modal approach.

Purpose of the Study:

• To conduct a multi-modal meta-analysis of brain alterations in chronic pain using structural MRI, resting-state functional connectivity, and functional MRI during pain processing.
• To identify consistent structural and functional brain changes associated with chronic pain.

Main Methods:

• Systematic literature search of PubMed, Embase, Medline, and Web of Science up to May 2022.
• Voxel-wise meta-analyses using seed-based d mapping for structural, functional connectivity, and pain processing data.
• Conjunction analyses to identify overlapping alterations across modalities.

Main Results:

• Chronic pain patients exhibit structural and functional changes in the insular cortex (reduced gray matter, altered connectivity, heightened activation).
• Distinct insular cortex activation patterns were observed for pain processing versus anticipation.
• The superior temporal gyrus and superior frontal gyrus showed cross-modal alterations.

Conclusions:

• This multi-modal meta-analysis confirms consistent structural and functional brain alterations in chronic pain.
• Findings highlight the complex interplay between structural and functional changes in the chronic pain brain.
• The study advances understanding of the neural underpinnings of chronic pain.