Background & Aims

Electrical stimulation is one of the common non-pharmaceutical therapeutic approaches for migraine prevention. Patients with migraine often demonstrate elevated cortical activity in comparison to healthy individuals (HC) (Bjørk et al., 2009). The median nerve stimulation (MNS), which can regulate neural processes (Chen et al., 2018; Li et al., 2016), is a potential method to modulate brain activity and connectivity. This study investigated the effect of sensory-level MNS intervention on migraine prevention, pain thresholds, and cortical activities in migraine without aura (MwoA).

Methods

Twenty-four HC and Twenty-three patients with MwoA underwent 30-minute 1 Hz MNS on their left volar forearm. In addition, MwoA underwent an eight-week intervention, receiving daily MNS on the same spot. Electronic headache diary was used to record monthly headache days (MHD) of MwoA participants. Electroencephalogram (EEG) (32-channel actiCHamp Plus, Brain Products GmbH, Gilching, Germany) was recorded before, during, and after a single session of 30-minute MNS. Additionally, EEG was collected at the baseline, the 8th week (POST), and the 12th week (Follow up, F/U) of the intervention. The relative power spectral density (rPSD) and coherence of EEG across frontal, parietal contralateral/ ipsilateral, temporal contralateral/ ipsilateral, and occipital regions were analyzed.

Results

At baseline, a higher theta rPSD (4-8 Hz) (parietal contralateral: p=0.027; temporal contralateral: p=0.040) and low-gamma rPSD (30-50 Hz) (frontal: p=0.001; parietal contralateral/ ipsilateral: p=0.001, p<0.001; temporal contralateral/ ipsilateral: p=0.001, p=0.002, and occipital p=0.032) was observed in MwoA compared to HC. The delta and theta coherence increased immediately after a 30-minute MNS, whereas decreased low-gamma coherence was observed in the MwoA. After an 8-week intervention, MHD was significantly reduced at POST (-3.3 days/month) and F/U (-3.2 days/month). Notably, compared with baseline, there was a decrease in low-gamma rPSD (POST: p=0.040; F/U: p=0.001) in the occipital region, and the low-gamma coherence in all brain regions consistently decreased at both the POST and F/U assessments.

Conclusions

Our preliminary findings suggest that an eight-week intervention of 1 Hz MNS can reduce MHD and induce consistent alterations in cortical activity among patients with MwoA. ?e found decreased low-gamma rPSD and MHD; future studies are warranted to understand whether the changes in EEG and MHD correlate. We speculate that MNS might induce the central nervous system regain the gain control of pain, and potentially lead the migraine brain closer to the healthy brain.

References

1. Bjørk, M. H., Stovner, L. J., Engstrøm, M., Stjern, M., Hagen, K., & Sand, T. (2009). Interictal quantitative EEG in migraine: a blinded controlled study. J Headache Pain, 10(5), 331-339. https://doi.org/10.1007/s10194-009-0140-4
2. Chen, Y. H., Lee, H. J., Lee, M. T., Wu, Y. T., Lee, Y. H., Hwang, L. L., Hung, M. S., Zimmer, A., Mackie, K., & Chiou, L. C. (2018). Median nerve stimulation induces analgesia via orexin-initiated endocannabinoid disinhibition in the periaqueductal gray. Proc Natl Acad Sci U S A, 115(45), E10720-e10729. https://doi.org/10.1073/pnas.1807991115
3. Li, F., Xiang, J., Wu, T., Zhu, D., & Shi, J. (2016). Abnormal resting-state brain activity in headache-free migraine patients: A magnetoencephalography study. Clinical Neurophysiology, 127(8), 2855-2861. https://doi.org/https://doi.org/10.1016/j.clinph.2016.05.015

Presenting Author

Yi-Wun Lin

Poster Authors

Yi Wun Lin

PhD

National Yang Ming Chiao Tung University

Lead Author

Li-Ling Hope Pan

PhD

Brain Research Center, National Yang Ming Chiao Tung University

Lead Author

Shuu-Jiun Wang

PhD

College of Medicine, National Yang Ming Chiao Tung University

Lead Author

Li-Wei Chou

PhD

Department of Physical Therapy and Assistive Technology, National Yang Ming Chiao Tung University

Lead Author

Topics

  • Treatment/Management: Interventional Therapies – Neuromodulation