Tracking tDCS induced grey matter changes in episodic migraine: a randomized controlled trial

Area of Science:

• Neuroscience
• Neurology
• Medical Imaging

Background:

• Episodic migraine is associated with structural brain alterations in pain-related areas, including the occipital cortex.
• Transcranial direct current stimulation (tDCS) is a proven prophylactic treatment for migraine attacks.
• The dynamic modulation of structural brain changes by tDCS in migraineurs remains understudied.

Purpose of the Study:

• To longitudinally track grey matter volume changes in occipital regions of episodic migraineurs during and after occipital tDCS treatment.
• To investigate the relationship between tDCS treatment, clinical migraine improvement, and structural brain plasticity.
• To assess the potential of neuroimaging biomarkers for monitoring migraine treatment response.

Main Methods:

• A single-blind, sham-controlled study involving 24 episodic migraineurs randomized to verum or sham occipital tDCS for 28 days.
• Structural MRI scans were acquired at baseline, 1.5 months, and 5.5 months post-treatment.
• Tensor-based morphometry was used to analyze longitudinal grey matter volume changes in migraineurs compared to 31 healthy controls.

Main Results:

• Migraineurs exhibited increased grey matter volume in the left lingual gyrus compared to controls at baseline.
• Four weeks of tDCS treatment reduced migraine frequency by 1.9 days/month.
• Treatment-associated migraine reduction was paralleled by a decrease in left lingual gyrus grey matter volume, overlapping with baseline levels.

Conclusions:

• Migraineurs present with increased grey matter volume in the lingual gyrus, which is modifiable by tDCS.
• Structural plasticity in the lingual gyrus, as measured by MRI, can be influenced by tDCS treatment in migraineurs.
• Tracking structural changes offers a potential neuroimaging biomarker for monitoring the efficacy of migraine treatments.