Abnormal brain activity in patients with migraine without aura based on resting-state functional magnetic resonance imaging

Migraine is a neurovascular disorder that adversely affects both individuals and society. Although previous studies have observed abnormal brain activity in patients with migraine, the specific patterns of neural dysfunction and their relationship with clinical symptoms remain incompletely understood. Resting-state functional magnetic resonance imaging data and clinical information were collected from 39 patients with migraine without aura (MwoA) and 26 healthy controls (HC). The amplitude of low-frequency fluctuations (zALFF), regional homogeneity (ReHo), and independent component analysis (ICA) were used to examine local brain activity and functional network alterations in patients with MwoA. Sleep quality was assessed using the Pittsburgh Sleep Quality Index (PSQI). Group comparisons were conducted with age, sex, years of education, Zung Self-Rating Depression Scale (SDS), Self-Rating Anxiety Scale (SAS), and PSQI scores as covariates. Pearson correlation analysis was used to explore associations between abnormal brain activity and clinical scale scores. Compared with HC, the MwoA group exhibited significantly higher scores on the SDS, SAS, and PSQI (all p < 0.001). The zALFF values were significantly decreased in the bilateral inferior temporal gyrus (ITG), and ReHo values were decreased in the left caudate nucleus (CN) in the MwoA group ( p < 0.05). HC showed increased functional connectivity in the bilateral lingual gyrus, right middle temporal gyrus, right inferior parietal lobule and supramarginal gyrus, right precuneus, left middle frontal gyrus, and right precentral gyrus ( p < 0.05). After adjusting for SDS, SAS, and PSQI, the original zALFF and ReHo differences were not significant; however, within-network connectivity decreases persisted in 13 of 23 ICA components, with one surviving Bonferroni correction (p_corrected = 0.019). Exploratory correlation analyses revealed that right PCU functional connectivity was positively correlated with PCS scores ( r = 0.426, p = 0.007), surviving Bonferroni correction, while right ITG–6-item Headache Impact Test ( r = − 0.359, p = 0.025) and left CN–duration ( r = − 0.373, p = 0.019) correlations did not survive correction. This exploratory study provides preliminary insights into the neural mechanisms involved in emotional and pain processing in patients with MwoA. By demonstrating that large-scale network connectivity alterations persist after controlling for mood and sleep, the findings distinguish migraine-specific neural changes from comorbid psychiatric symptoms. These results contribute to a better understanding of migraine pathophysiology and provide a theoretical basis for future research. However, validation in larger, independent cohorts is necessary before any clinical applications can be considered.