title: Resilience in migraine brains: decrease of coherence after photic stimulation.
abstract: BACKGROUND
  During migraine attacks, patients generally have photophobia and phonophobia and seek for environments with less sensorial stimulation. Present work aimed to quantify cortical partial directed coherence (PDC) of electroencephalographic (EEG) recordings from migraine patients and controls in occipital, parietal, and frontal areas with or without photic stimulation. Our hypothesis is that migraine patients with visual aura might have neuronal networks with higher coherence than controls even in interictal periods due to a predisposition in sensory cortical processing.
  
  
  METHODS
  Eleven adult women with migraine with visual aura (at least 48 h without previous attacks) and seven healthy adult woman were submitted to EEG recording in basal state and during photic stimulation.
  
  
  RESULTS
  When compared to healthy volunteers, migraine patients show different coherence profiles. Migraine patients had greater coherence than controls during the basal period (without photic stimulation), showing predisposition for sensory processing in many frequency ranges. After photic stimulation, patients showed a decrease in cortical coherence while controls had an increase.
  
  
  CONCLUSIONS
  When compared to healty subjects, migraineurs show increased cortical coherence before photic stimulation, but a decrease when stimulation starts. This may be the expression of a resilience mechanism that allows migraineurs the interictal period. The PDC analysis permits to address a patient coherence profile, or "coherence map," that can be utilized for management of the headache disorder or following up treatments.
authors: Grupo de Neurodinâmica, Departamento de Fisiologia e Farmacologia, Universidade Federal de Pernambuco Brazil.
authors: Mayara
authors: M
authors: Mendonça-de-Souza
authors: Ubirakitan M
authors: UM
authors: Monteiro
authors: Amana S
authors: AS
authors: Bezerra
authors: Ana P
authors: AP
authors: Silva-de-Oliveira
authors: Belvânia R
authors: BR
authors: Ventura-da-Silva
authors: Marcelo S
authors: MS
authors: Barbosa
authors: Josiane A
authors: JA
authors: de Souza
authors: Elisângela C
authors: EC
authors: Criado
authors: Maria C M
authors: MC
authors: Ferrarezi
authors: Giselly de A
authors: Gde A
authors: Alencar
authors: Otávio G
authors: OG
authors: Lins
authors: Maria das G W S
authors: Md
authors: Coriolano
authors: Belmira L S A
authors: BL
authors: Costa
authors: Marcelo C A
authors: MC
authors: Rodrigues