Analysis is based on functional magnetic resonance imaging to provide insight into the effective connectivity.
Individuals with migraine without aura (MwoA) showed a decreased dynamic amplitude of low frequency fluctuation (dALFF) variability in the rostral ventromedial medulla (RVM), right precuneus (PCUN.R), and superior lobe of left cerebellum (Cerebellum_Crus1_L) but progressively recovered after an individual’s first and 12th acupuncture treatment session, according to the results of a study published in Frontiers in Neuroscience.
Investigators also found that there were gradual increases in dynamic effective connectivity (DEC) variability in RVM outflow to the left insula, right middle frontal gyrus, right precentral gyrus, and right supramarginal gyrus.
Additionally, there were gradual increases in DEC variability in the right fusiform gyrus inflow, from the Cerebellum_Crus1_L outflow to the left middle occipital gyrus and the left precentral gyrus and from PCUN.R outflow to the right thalamus.
Investigators also found that the dALFF variabilities were positively correlated with the frequency of migraine attacks, as well as negatively correlated with disease duration at the individual’s baseline.
The factors of the Granger causality analysis showed that the DEC variability also correlated with positive Migraine-Specific Quality of Life Questionnaires scores but had negative correlations with the frequency of migraine attacks and visual analog scale scores after the 12th treatment with acupuncture.
Investigators analyzed the results by functional magnetic resonance imaging (fMRI) in an effort to provide insight into the dynamic alterations of brain activity and effective connectivity in individuals who have MwoA.
Investigators included 40 individuals with MwoA from outpatient practices in the Department of Neurology or Acupuncture at Shuguang Hospital. They also included 36 healthy individuals who were used as controls, who were matched by age and education level to the individuals with MwoA and were right-handed.
The individuals had never been diagnosed with alcohol or drug abuse, head trauma, , or neurological or psychiatric disorders.
The observation period was 10 weeks, where weeks 1 through 4 consisted of the baseline period, and all individuals recorded their headaches during this phase. Weeks 5 through 10 consisted of the intervention period, where individuals received standard acupuncture treatment. They also kept records of their headaches.
Additionally, fMRI scans were administered before the first session and after the 12th sessions for individuals with MwoA. Investigators performed the fMRI scan within 1 hour before or after the acupuncture treatment. The control group only received fMRI scans at baseline.
All individuals had been migraine-free for at least 72 hours before the fMRI scans.
Individuals received 12 sessions of acupuncture at 2 sessions a week for 6 weeks. Every session lasted 20 minutes with sterile disposable acupuncture needles that were 25 to 40 mm in length and 0.25 mm in diameter.
Electrical stimulation was applied bilaterally at GB20 and GB8 with a frequency of 2 Hz and intensity ranging from 0.1 to 1.0 mA, depending on the individual’s tolerance.
Individuals did not take any conventional medication for migraines during the study period. However, in cases of severe pain, extended-release ibuprofen at 300 mg was allowed.
Chen Y, Kang Y, Luo S, Liu S, et al. The cumulative therapeutic effect of acupuncture in patients with migraine without aura: evidence from dynamic alterations of intrinsic brain activity and effective connectivity. Front Neurosci. 2022;16:925698. doi:10.3389/fnins.2022.925698