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Background: Brief 5Hz repetitive transcranial magnetic\udstimulation (rTMS) trains at 120% of the resting- motorthreshold\ud(RMT) intensity determine in healthy subjects a\udpotentiation of motor evoked potentials (MEPs), likely due\udto short-term presynaptic plasticity facilitation. We recently\udshowed paradoxical intensity-dependent MEP changes to\ud5Hz rTMS in migraine with MEP facilitation at 110% and\udinhibition at 130% RMT. This provides evidence of both\udhyper-responsivity and self-limiting hyperexcitability\udcapacity in migraine, likely due to earlier activation of\udinhibitory homeostatic plasticity mechanisms. To explore\udthis, we applied in migraineurs cathodal transcranial Direct\udCurrent Stimulation (tDCS) to reduce motor-cortical\udexcitability and subsequently reassess motor-cortical\udresponse to 5Hz rTMS trains at 130% RMT- intensity.\udMethods: 10 migraine with aura patients received 5Hz\udrTMS of motor cortex at 130% RMT intensity (10 pulses),\udrecording MEP from contralateral abductor pollicis brevis\ud(APB). This protocol was preconditioned by cathodal tDCS\ud(10 min, 1mA intensity). Sham cathodal tDCS was used as\udcontrol.\udResults: As expected MEP amplitude decreased significantly\udduring trains of 5Hz before tDCS preconditioning or\udwith sham tDCS. Conversely, after inhibitory preconditioning\udwith cathodal tDCS, 5Hz rTMS trains determined a\udreduction in the first MEP size and a trend toward MEP\udfacilation during the trains.\udConclusions: Inhibitory cathodal tDCS preconditioning is\udable to normalize the response of migraine motor-cortex to\udrTMS trains at 130% of RMT. This supports the hypothesis\udthat in migraine motor cortex the mechanisms of short-term\udpresynaptic plasticity evaluated by 5Hz rTMS trains could\udbe affected intericatally by an abnormal increased cortical\udexcitability level