A potential neuroimaging biomarker for depression in migraine patients: imbalance in excitation and inhibition in the medial superior frontal cortex.

Background: Depression is a common psychological and behavioural symptom experienced by people with migraines. However, the underlying neural mechanisms of depressive symptoms in this population are unclear. Methods: In this study, we investigated the neural mechanisms underlying excitation-inhibition imbalance in patients with migraine accompanied by depressive symptoms (MD) using the Hurst exponent. We used Analysis of covariance to compare differences in the Hurst exponent between patients with MD, patients with migraine accompanied by non-depressive symptoms (MnD), and healthy controls (HC). Spearman's correlation analysis was used to calculate the correlation between the Hurst exponent of different brain regions and clinical variables. Results: Compared with patients with migraine accompanied by MnD, patients with MD showed an increased Hurst exponent in the left lingual gyrus and medial superior frontal cortex. Compared with HC, MD showed an increased Hurst exponent in the right cerebellum crus 1 and right lingual gyrus. Compared with HC, MnD showed an increased Hurst exponent in the left cerebellum crus 2 and medial superior frontal cortex. The Hurst exponent of the medial superior frontal cortex in patients with migraine was significantly positively correlated with depression scores (r = 0.3501, p = 0.0001). Conclusions: Our study has identified imaging features of excitatory-inhibitory imbalance in MD. Imbalances in excitation and inhibition in the medial superior frontal cortex may serve as a promising candidate imaging marker for diagnosing and intervening in depressive symptoms in migraine.