Search results for "visual cortex excitability"
showing 2 items of 2 documents
Modulation of visual cortex excitability in migraine with aura: effects of valproate therapy.
2009
We explored the effects of valproate treatment on visual cortex excitability changes in migraine with aura patients. Abnormal cortical excitability has been suggested to play an important role in the etiopathogenesis of migraine; in particular, it has been suggested a failure of inhibitory circuits in migraine with aura. Valproate acts as a central GABA agonist and it is reasonable suppose that VPA could modify cortical excitability state. Phosphene threshold (PT) was assessed at baseline and after 1 Hz rTMS before and after one month therapy. We found that low-frequency rTMS in drug-free migraineurs decreased PT, while the treatment with the GABA agonist valproate is able to revert the eff…
Lack of effects of low frequency repetitive transcranial magnetic stimulation on alpha rhythm phase synchronization in migraine patients
2010
The study aimed to test the modulation induced by 1 Hz repetitive Transcranial Magnetic Stimulation (rTMS) of the occipital cortex on the alpha phase synchronization under repetitive flash stimuli in 15 migraine without aura patients compared to 10 controls. The EEG was recorded by 7 channels, while flash stimuli were delivered at 9, 18, 21 and 24 Hz in basal, rTMS (15 min of 1 Hz stimulation of the occipital cortex) and sham conditions. Migraine patients displayed increased alpha-band phase synchronization under visual stimulation, while an overall desynchronizing effect was evident in controls. The rTMS resulted in a slight increase of synchronization index in migraine patients, which did…