Disrupted Dynamic Functional Connectivity of the Visual Network in Episodic Patients with Migraine without Aura

Abstract

Background. Visual symptoms are common in patients with migraine, even in interictal periods. The purpose was to assess the association between dynamic functional connectivity (dFC) of the visual cortex and clinical characteristics in migraine without aura (MwoA) patients. Methods. We enrolled fifty-five MwoA patients as well as fifty gender- and age-matched healthy controls. Regional visual cortex alterations were investigated using regional homogeneity (ReHo) and amplitude of low-frequency fluctuation (ALFF). Then, significant regions were selected as seeds for conducting dFC between the visual cortex and the whole brain. Results. Relative to healthy controls, MwoA patients exhibited decreased ReHo and ALFF values in the right lingual gyrus (LG) and increased ALFF values in the prefrontal cortex. The right LG showed abnormal dFC within the visual cortex and with other core brain networks. Additionally, ReHo values for the right LG were correlated with duration of disease and ALFF values of the right inferior frontal gyrus and middle frontal gyrus were correlated with headache frequency and anxiety scores, respectively. Moreover, the abnormal dFC of the right LG with bilateral cuneus was positively correlated with anxiety scores. Conclusions. The dFC abnormalities of the visual cortex may be involved in pain integration with multinetworks and associated with anxiety disorder in episodic MwoA patients.

Dynamic Resting-State Functional Connectivity in Migraineurs

“…All studies performed d-FC analyses using the sliding window method [6][7][8][9][10][11]. However, the analyzed data using the sliding window method differed from study to study: three studies used ICs obtained from group ICA (GICA) [6,8,9], two studies used predefined ROIs [7,11] and one study used the seed obtained from regional homogeneity (ReHo) and amplitude of low frequency fluctuations (ALFF) analyses [9].…”

“…All 6 studies were conducted in migraine patients [6][7][8][9][10][11]. The diagnosis of migraine differed according to the purpose of the study and included migraine [7], migraine without aura (MwoA) [6,10,11], episodic migraine (EM) [8], and chronic migraine (CM) [9,11]. The number of participants, including controls, ranged from 37 to 159 [6][7][8][9][10][11].…”

“…Of these, the prodromal, aura, and postictal phases are together referred to as the peri-ictal phase. MRI images were acquired during the interictal phase in three studies [6,10,11], and one study [9] assumed an interictal phase. Two studies [7,8] acquired images of all phases, one of which [8] classified the images into the preictal phase and ictal/peri-ictal phases.…”

“…Dynamic connectivity analysis better reflects fluctuations in neuronal activity and helps identify networks that cannot be detected by static functional analysis [4,5]. We have described previous studies using dynamic connectivity analysis in migraine patients, including our previous study [6][7][8][9][10][11]. In this review, we provided insight into resting-state dynamic functional analysis in migraine patients.…”

Altered Brain Function in Treatment-Resistant and Non-treatment-resistant Depression Patients: A Resting-State Functional Magnetic Resonance Imaging Study

“…ALFF reflects the intensity of spontaneous activity in a region of the brain over a short period of time by calculating the average amplitude of low-frequency oscillations in that region (24). However, the diseases currently studied using a combined ALFF and ReHo approach mainly include Parkinson's disease (26), generalized anxiety disorder (25), bipolar disorder (27), and migraine without aura (28), while differential studies of TRD and nTRD are lacking. So far, there have been some studies on the difference between TRD and nTRD, but most of them use ALFF or ReHo as a single indicator.…”