Somatosensory evoked high-frequency oscillations reflecting thalamo-cortical activity are decreased in migraine patients between attacks

摘要: A deficit of habituation in cortical information processing, including somatosensory evoked potentials (SSEPs), is the most consistent neurophysiological abnormality migraine patients between attacks. To explore further mechanisms underlying this interictal neural dysfunction, we have studied high-frequency oscillations (HFOs) embedded SSEPs because they are thought to reflect spike activity thalamo-cortical cholinergic fibres (early HFOs) and inhibitory GABAergic interneurons (late HFOs). Untreated with (MA) without (MO) aura were recorded during (n = 13: nine MO, four MA) attacks 29: 14 15 compared healthy volunteers. filtered off-line (digital band-pass 450 750 Hz) extract two HFO bursts from broad-band contralateral N20 response obtained by median nerve stimulation. In both groups, amplitudes latencies conventional interictally cervical parietal active electrodes not significantly different those found contrast, maximum peak-to-peak amplitude area under rectified curve early burst smaller MA MO than There was no significant difference later migraineurs During attacks, all electrophysiological measurements similar Thalamo-cortical activation, as reflected SSEP burst, may thus be reduced interictally, but normalizes an attack, whereas intracortical inhibition, indexed late normal at any time. This supports hypothesis that due a pre-activation level sensory cortices increased excitability or inhibition.