Original

The Journal of Headache and Pain

, Volume 11, Issue 2, pp 115-121

Open Access This content is freely available online to anyone, anywhere at any time.

Lack of cold pressor test-induced effect on visual-evoked potentials in migraine

  • Gianluca CoppolaAffiliated withDepartment of Neurophysiology of Vision and Neurophthalmology, G. B. Bietti Eye Foundation, IRCCS Email author 
  • , Antonio CurràAffiliated withDepartment of Neurological Sciences, Ospedale A. Fiorini-Polo Pontino, “Sapienza” University
  • , Mariano SerraoAffiliated withUniversity Centre for Adaptive Disorders and Headache (UCADH), “Sapienza” University of Rome, Polo Pontino, ICOTIRCCS Neuromed
  • , Cherubino Di LorenzoAffiliated withUniversity Centre for Adaptive Disorders and Headache (UCADH), “Sapienza” University of Rome, Polo Pontino, ICOT
  • , Manuela GoriniAffiliated withDepartment of Neurological Sciences, Ospedale A. Fiorini-Polo Pontino, “Sapienza” University
  • , Elisa PorrettaAffiliated withUniversity Centre for Adaptive Disorders and Headache (UCADH), “Sapienza” University of Rome, Polo Pontino, ICOT
  • , Alessia AlibardiAffiliated withDepartment of Neurological Sciences, Ospedale A. Fiorini-Polo Pontino, “Sapienza” University
  • , Vincenzo ParisiAffiliated withDepartment of Neurophysiology of Vision and Neurophthalmology, G. B. Bietti Eye Foundation, IRCCSUniversity of Rome “Campus Biomedico”
  • , Francesco PierelliAffiliated withUniversity Centre for Adaptive Disorders and Headache (UCADH), “Sapienza” University of Rome, Polo Pontino, ICOTIRCCS Neuromed

Abstract

In patients with migraine, the various sensory stimulation modalities, including visual stimuli, invariably fail to elicit the normal response habituation. Whether this lack of habituation depends on abnormal activity in the sub-cortical structures responsible for processing incoming information as well as nociception and antinociception or on abnormal cortical excitability per se remains debateable. To find out whether inducing tonic pain in the hand by cold pressure test (CPT) alters the lack of visual-evoked potential (VEP) habituation in migraineurs without aura studied between attacks we recorded VEPs in 19 healthy subjects and in 12 migraine patients during four experimental conditions: baseline; no-pain (hand held in warm water, 25°C); pain (hand held in cold water, 2–4°C); and after-effects. We measured P100 amplitudes from six blocks of 100 sweeps, and assessed habituation from amplitude changes between the six sequential blocks. In healthy subjects, the CPT decreased block 1 VEP amplitude and abolished the normal VEP habituation (amplitude decrease to repeated stimulation) in patients with migraine studied between attacks; it left block 1 VEP amplitude and abnormal VEP habituation unchanged. These findings suggest that the interictal cortical dysfunction induced by migraine prevents the cortical changes induced by tonic painful stimulation both during pain and after pain ends. Because such cortical changes presumably reflect plasticity mechanisms in the stimulated cortex, our study suggests altered plasticity of sensory cortices in migraine. Whether this abnormality reflects abnormal functional activity in the subcortical structures subserving tonic pain activation remains conjectural.

Keywords

Migraine Cold pressor test Visual-evoked potentials Habituation Brainstem Thalamo-cortical activity