PMID- 30094517 OWN - NLM STAT- MEDLINE DCOM- 20181023 LR - 20181114 IS - 1129-2377 (Electronic) IS - 1129-2369 (Print) IS - 1129-2369 (Linking) VI - 19 IP - 1 DP - 2018 Aug 9 TI - Intracortical facilitation within the migraine motor cortex depends on the stimulation intensity. A paired-pulse TMS study. PG - 65 LID - 10.1186/s10194-018-0897-4 [doi] LID - 65 AB - INTRODUCTION: Connectivity within the primary motor cortex can be measured using the paired-pulse transcranial magnetic stimulation (TMS) paradigm. This evaluates the effect of a first conditioning stimulus on the motor evoked potential (MEP) elicited by a second test stimulus when different interstimulus intervals are used. Aim of the present study was to provide, in patients suffering from migraine without aura (MwoA), additional information on intracortical facilitation (ICF), short intracortical inhibition (SICI), and long intracortical inhibition (LICI), using different intensities of the test stimulus (TS). METHODS: We enrolled 24 patients with episodic MwoA and 24 age- and sex-matched healthy volunteers. Both patients and controls were randomly assigned to two different experimental groups: the first group underwent evaluation of ICF, while in the second group we assessed SICI and LICI. All these measures were assessed by using three different suprathreshold intensities of the TS (110%, 130% and 150% of the resting motor threshold, RMT). Interstimulus intervals (ISIs) of 10 ms were used for testing ICF, while SICI and LICI were carried out by using 2 ms and 100 ms ISIs respectively. All migraine patients underwent the experimental protocol while in the interictal pain-free state. RESULTS: A main finding of the study was that an increased ICF could be seen in migraineurs as compared to the healthy subjects only by using a 110% intensity of the TS. Instead, no significant differences were observed between patients and controls as regards both measures of intracortical inhibition. CONCLUSION: We show that hyperresponsivity of the glutamatergic intracortical circuits can be detected in the migraine motor cortex only by applying a low suprathreshold intensity of stimulation. Our results strengthen the notion that, to be reliable, the assessment of cortical excitability in migraine should always include evaluation of the cortical response to different stimulation intensities. FAU - Cosentino, Giuseppe AU - Cosentino G AD - Department of Experimental Biomedicine and Clinical Neurosciences (BioNeC), University of Palermo, Azienda Ospedaliera Universitaria Policlinico "Paolo Giaccone", Via Del Vespro, 143, 90100, Palermo, Italy. FAU - Di Marco, Salvatore AU - Di Marco S AD - Department of Experimental Biomedicine and Clinical Neurosciences (BioNeC), University of Palermo, Azienda Ospedaliera Universitaria Policlinico "Paolo Giaccone", Via Del Vespro, 143, 90100, Palermo, Italy. FAU - Ferlisi, Salvatore AU - Ferlisi S AD - Department of Experimental Biomedicine and Clinical Neurosciences (BioNeC), University of Palermo, Azienda Ospedaliera Universitaria Policlinico "Paolo Giaccone", Via Del Vespro, 143, 90100, Palermo, Italy. FAU - Valentino, Francesca AU - Valentino F AD - Department of Experimental Biomedicine and Clinical Neurosciences (BioNeC), University of Palermo, Azienda Ospedaliera Universitaria Policlinico "Paolo Giaccone", Via Del Vespro, 143, 90100, Palermo, Italy. FAU - Capitano, Walter M AU - Capitano WM AD - Department of Experimental Biomedicine and Clinical Neurosciences (BioNeC), University of Palermo, Azienda Ospedaliera Universitaria Policlinico "Paolo Giaccone", Via Del Vespro, 143, 90100, Palermo, Italy. FAU - Fierro, Brigida AU - Fierro B AD - Department of Experimental Biomedicine and Clinical Neurosciences (BioNeC), University of Palermo, Azienda Ospedaliera Universitaria Policlinico "Paolo Giaccone", Via Del Vespro, 143, 90100, Palermo, Italy. FAU - Brighina, Filippo AU - Brighina F AD - Department of Experimental Biomedicine and Clinical Neurosciences (BioNeC), University of Palermo, Azienda Ospedaliera Universitaria Policlinico "Paolo Giaccone", Via Del Vespro, 143, 90100, Palermo, Italy. filippo.brighina@unipa.it. LA - eng PT - Journal Article PT - Randomized Controlled Trial DEP - 20180809 PL - England TA - J Headache Pain JT - The journal of headache and pain JID - 100940562 SB - IM MH - Adult MH - Electromyography/methods MH - Evoked Potentials, Motor/*physiology MH - Female MH - Humans MH - Male MH - Middle Aged MH - Migraine without Aura/*physiopathology/*therapy MH - Motor Cortex/*physiopathology MH - Neural Inhibition/physiology MH - Rest/physiology MH - Transcranial Magnetic Stimulation/*methods MH - Young Adult PMC - PMC6085216 OTO - NOTNLM OT - Cortical excitability OT - Glutamate OT - Migraine without aura OT - Motor cortex, paired pulse OT - Transcranial magnetic stimulation COIS- The study was approved by the Local Ethics Committee of the University Polyclinic of Palermo. Prior to the experiment all subjects gave their informed consent to participate according to the Declaration of Helsinki. All authors gave their consent for publication of the ms. The authors declare that they have no competing interests. Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. EDAT- 2018/08/11 06:00 MHDA- 2018/10/24 06:00 PMCR- 2018/08/09 CRDT- 2018/08/11 06:00 PHST- 2018/06/30 00:00 [received] PHST- 2018/07/31 00:00 [accepted] PHST- 2018/08/11 06:00 [entrez] PHST- 2018/08/11 06:00 [pubmed] PHST- 2018/10/24 06:00 [medline] PHST- 2018/08/09 00:00 [pmc-release] AID - 10.1186/s10194-018-0897-4 [pii] AID - 897 [pii] AID - 10.1186/s10194-018-0897-4 [doi] PST - epublish SO - J Headache Pain. 2018 Aug 9;19(1):65. doi: 10.1186/s10194-018-0897-4.