Title:
Correlation between habituation of visual-evoked potentials and magnetophosphene thresholds in migraine: A case-control study.
Authors:
Ambrosini A; Iezzi E; Perrotta A; Kisialiou A; Nardella A; Berardelli A;
Pierelli F; Schoenen J.In stitution Ambrosini, Anna. IRCCS Neuromed, Headache Unit, Italy a
nna.ambrosini@neuromed.it. Iezzi, Ennio. IRCCS Neuromed, Clinical Neurophysiology Unit, Italy Perrotta, Armando. IRCCS Neuromed, Headache Unit, Italy. Kisialiou, Aliaksei. IRCCS San Raffaele Pisana, Unit of Clinical and Molecular Epidemiology, Italy. Nardella, Andrea . IRCCS Neuromed, Clinical Neurophysiology Unit, Italy. Berardelli, Alfredo. IRCCS Neuromed, Clinical Neurophysiology Unit, Italy Sapienza University of Rome, Department of Neurology and Psychiatry, Italy. Pierelli, Francesco. IRCCS Neuromed, Headache Unit, Italy Sapienza University of Rome, Department of Medical-Surgical Sciences and Biotechnologies, Italy. Schoenen, Jean. University of Liege – CHR Citadelle, University Dept. of Neurology, Headache Research Unit, Belgium.
Source Cephalalgia. 36(3):258-64, 2016 Mar.
Title:
Correlation between habituation of visual-evoked potentials and magnetophosphene thresholds in migraine: A case-control study.
INTRODUCTION:
In migraine most studies report an interictal deficit of habituation of visual-evoked potentials (VEP-hab) and reduced thresholds for phosphene induction (PT) by transcranial magnetic stimulation (TMS). We searched for a possible correlation between VEP-hab and PT in migraine patients and healthy controls to test whether they reflect the same pathophysiological abnormality.
METHODS:
We assessed PT and VEP-hab measured as the percentage change of
N1/P1 amplitude over six blocks of 100 responses in 15 healthy volunteers (HV) and in 13 episodic migraineurs without aura (MO) between attacks. Results were compared using Mann-Whitney U test. Interrelationships were examined using Spearman’s correlation.
RESULTS:
In MO patients VEP-hab was reduced compared to HV (p=0.001), while PT were not significantly different between HV and MO. There was no correlation between PT and VEP-hab in either group of participants.
CONCLUSIONS:
We confirm that in interictal migraine VEP habituation is deficient, but magnetophosphene threshold normal. VEP-hab and PT were not correlated with each other in healthy controls or in migraineurs. This finding suggests that they index different facets of cortical excitability
in migraine, i.e. a punctual normal measure of the cortical activation threshold for PT and a dynamic response pattern to repeated stimuli for VEP habituation.
Copyright:
International Headache Society 2015.
