Afra J, Proietti Cecchini A, Sándor P S, Schoenen J
Department of Neurology Semmelweis University of Medicine, Budapest, Hungary.
Clin Neurophysiol. 2000 Jun;111(6):1124-9. doi: 10.1016/s1388-2457(00)00271-6.
As both habituation of pattern reversal visual evoked potentials (PR-VEP) (Schoenen J, Wang W, Albert A, Delwaide PJ. Potentiation instead of habituation characterizes visual evoked potentials in migraine patients between attacks. Eur J Neurol 1995;2:115-122) and intensity dependence of auditory evoked cortical potentials (IDAP) (Wang W, Timsit-Berthier M, Schoenen J. Intensity dependence of auditory evoked potentials in migraine: an indication of cortical potentiation and low serotonergic neurotransmission? Neurology 1996;46:1404-1409) were found abnormal in migraine between attacks, we have searched for intraindividual correlations between both tests in 59 migraine patients (22 with aura [MA], 37 without aura [MO]) and in 23 healthy volunteers (HV).
Amplitude change of the PR-VEP N1-P1 was measured between the 1st and 5th block of 50 sequential averagings during continuous stimulation at 3.1 Hz. IDAP was computed from N1-P2 amplitudes of 100 averagings during stimulations at 40, 50, 60 and 70 dB SL. Amplitude-stimulus intensity function (ASF) slopes and amplitude changes between 40 and 70 dB were calculated. MO and MA differed from HV in PR-VEP amplitude change (P=0.007) and IDAP slope (P = 0.0004).
There was no significant correlation between VEP amplitude changes and IDAP slopes, nor between the latter two and attack frequency or disease duration. A negative correlation was found between the amplitude of the first block of averaged responses and potentiation of VEP in all subject groups (P = 0.03) as well as between the amplitude of the auditory evoked potential, at 40 dB, and the percentage of amplitude increase between 40 and 70 dB in MO (P = 0.004) and MA (P = 0.007). ASF slopes and 40 dB amplitudes were significantly correlated only in the MA group (P = 0.002). These results confirm the interictal deficit of habituation in cortical processing of repetitive visual and auditory information in migraine. Since there is no intraindividual correlation between the cortical responses to these sensory modalities they are complementary tools for the study of migraine and may help to identify subgroups of patients with distinct pathophysiological mechanisms.
The strong negative correlation between the initial amplitude of evoked potentials and their amplitude increase during subsequent averaging confirms that the response potentiation in migraine is likely to be due to a reduced preactivation level of sensory cortices.
由于发现偏头痛发作间期模式翻转视觉诱发电位（PR-VEP）的习惯化（Schoenen J, Wang W, Albert A, Delwaide PJ. 偏头痛发作间期患者视觉诱发电位的特征是增强而非习惯化。《欧洲神经病学杂志》1995年；2:115 - 122）以及听觉诱发电位的强度依赖性（IDAP）（Wang W, Timsit-Berthier M, Schoenen J. 偏头痛中听觉诱发电位的强度依赖性：皮质增强和低5-羟色胺能神经传递的一个指标？《神经病学》1996年；46:1404 - 1409）均异常，我们在59例偏头痛患者（22例有先兆[MA]，37例无先兆[MO]）和23名健康志愿者（HV）中寻找这两种测试之间的个体内相关性。
在3.1 Hz连续刺激期间，在50次连续平均的第1个和第5个块之间测量PR-VEP N1-P1的振幅变化。IDAP由40、50、60和70 dB SL刺激期间100次平均的N1-P2振幅计算得出。计算振幅-刺激强度函数（ASF）斜率以及40至70 dB之间的振幅变化。MO和MA在PR-VEP振幅变化（P = 0.007）和IDAP斜率（P = 0.0004）方面与HV不同。
VEP振幅变化与IDAP斜率之间、后两者与发作频率或病程之间均无显著相关性。在所有受试者组中，平均反应第一个块的振幅与VEP增强之间存在负相关（P = 0.03），在MO组（P = 0.004）和MA组（P = 0.007）中，40 dB时听觉诱发电位的振幅与40至70 dB之间的振幅增加百分比之间也存在负相关。ASF斜率和40 dB振幅仅在MA组中显著相关（P = 0.002）。这些结果证实了偏头痛发作间期在重复视觉和听觉信息的皮质处理中习惯化的缺陷。由于对这些感觉模式的皮质反应之间不存在个体内相关性，它们是研究偏头痛的互补工具，可能有助于识别具有不同病理生理机制的患者亚组。
诱发电位的初始振幅与其在随后平均过程中的振幅增加之间的强负相关证实，偏头痛中的反应增强可能是由于感觉皮质的预激活水平降低所致。
