Long-range inhibitory mechanisms in the visual system are impaired in migraine sufferers.
Cephalalgia
; 32(14): 1071-5, 2012 Oct.
Article
em En
| MEDLINE
| ID: mdl-22890276
ABSTRACT
BACKGROUND:
After viewing dynamic noise surrounding a homogeneous grey patch (artificial scotoma), observers perceive a prolonged twinkling-noise after-image within the unstimulated area. It has been suggested that noise-stimulated neurons induce a long-range inhibition in neurons within the artificial scotoma, which generates a rebound signal perceived as twinkling noise following noise termination. We used this paradigm to test whether migraineurs have enhanced excitability or weakened inhibition.METHODS:
Twinkling-noise duration was measured in 13 headache-free volunteers, 13 migraineurs with aura and 13 migraineurs without aura.RESULTS:
The durations of the after-image were significantly shorter for both migraine groups compared to controls.DISCUSSION:
Enhanced excitation of noise-activated neurons in migraineurs would produce stronger rebound activity and longer after-image durations, while weakened inhibitory mechanisms would diminish the rebound activity and shorten the after-image durations compared to control subjects. The results suggest that cortical inhibitory mechanisms might be impaired in migraineurs with and without aura.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Escotoma
/
Córtex Visual
/
Percepção Visual
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Enxaqueca com Aura
/
Enxaqueca sem Aura
/
Pós-Imagem
Tipo de estudo:
Etiology_studies
Limite:
Adult
/
Female
/
Humans
/
Male
Idioma:
En
Ano de publicação:
2012
Tipo de documento:
Article