# Investigating changes of functional brain networks in painful temporomandibular disorders: a resting-state fMRI study

## TL;DR

This study uses resting-state fMRI to find brain network changes in people with painful temporomandibular disorders, linking these changes to emotional and clinical factors.

## Contribution

The study identifies altered brain network properties in TMDp patients and links them to depression and anxiety.

## Key findings

- TMDp patients showed decreased clustering coefficient and local efficiency in brain networks.
- Local efficiency was positively correlated with depressive and anxious variables in TMDp patients.

## Abstract

Background: Temporomandibular
disorders (TMD), particularly pain-related TMD (TMDp), are closely associated
with social and psychological factors. However, the neuromechanisms of pain of
TMDp are still currently unclear. This study aimed to investigate the altered
topological properties of the brain network in the TMDp patients using
resting-state functional magnetic resonance imaging (rs-fMRI), and to explore the
association between these parameters and emotional and clinical variables of
TMDp. Methods: A total of 41 TMDp patients and 33 age- and
gender-matched healthy controls (NCs) were recruited, and rs-fMRI data were
obtained from a 3.0T MR scanner. The topological properties of brain functional
networks were calculated based on the rs-fMRI data and were compared between two
groups to investigate the altered topological characteristics in TMDp. The
correlation analysis was also performed between the abnormal topological
characteristics and the clinical variables in TMDp patients. Results:
TMDp patients presented significantly decreased clustering coefficient (Cp) and
decreased local efficiency (Eloc) when sparsity threshold was
0.05 and 0.06 compared with NCs (p < 0.05), and the Eloc values when
sparsity threshold was 0.06 were positively correlated with depressive (r = 0.319, p = 0.042) and anxious (r = 0.348, p =
0.026) variables in TMDp patients.
Conclusions: The current study
demonstrated the abnormal topological changes of the brain network were observed
in TMDp, which could be helpful in understanding the neuromechanisms of pain of
TMDp. The topological properties of the brain network based on rs-fMRI could be
considered as a new simple tool to monitor the dysfunction network of the brain
in TMDp.