Increased effective connectivity from the hypothalamus to the left superior frontal gyrus and its association with visual analogue scale in persons with migraines.

BACKGROUND

In recent years, several functional imaging studies have shown that the hypothalamus is closely associated with migraine and have suggested that the hypothalamus may be a potential site of migraine generation. Studying the characteristics of the functional network of the hypothalamus in persons with migraines may help to understand the neural mechanisms of migraine. We thus used resting-state functional magnetic resonance imaging (rsfMRI) and Granger causal analysis to investigate the effective connectivity (EC) of the hypothalamus in persons with migraines.

METHODS

The study included 17 healthy volunteers and 39 persons with migraines. The EC calculation was based on rsfMRI data from a 3-T magnetic resonance imaging scanner. The brain networks of the hypothalamus were compared using a general linear model to determine if there were any differences between the two groups. We used Pearson correlation analysis to examine the correlation between EC values in abnormal brain regions and clinical variables.

RESULTS

Compared with healthy controls, those with migraines showed decreased EC from the hypothalamus to the left fusiform and increased EC from the hypothalamus to the medial frontal gyrus/orbital part, right lingual gyrus, left superior frontal gyrus, and right middle frontal gyrus (P<0.05). Meanwhile, persons with migraines also showed decreased EC from the left middle frontal gyrus and right medial frontal gyrus/orbital part to the hypothalamus (P<0.05). EC from the hypothalamus to the left superior frontal gyrus correlated significantly and positively with the visual analogue scale in those with migraines (r=-0.3820; P=0.0164).

CONCLUSIONS

Disturbances in the EC between the hypothalamus and the prefrontal gyrus and visual cortex may play a key role in the neuropathological features of persons with migraines. The current study adds to our understanding of the complexity of migraine mechanisms.