Department of Otorhinolaryngology, Faculty of Medicine Carl Gustav Carus, Smell & Taste Clinic, Technische Universität Dresden, Fetscherstraße 74, 01307, Dresden, Germany.
Department of Psychology, Uppsala University, 752 37, Uppsala, Sweden.
J Headache Pain. 2023 May 17;24(1):55. doi: 10.1186/s10194-023-01592-3.
Accumulating data emphasizes the importance of olfaction in migraine pathophysiology. However, there are only a few studies evaluating how the migraine brain processes olfactory stimulation, and virtually no studies comparing patients with and without aura in this context.
This cross-sectional study recorded event-related potentials from 64 electrodes during a pure olfactory or pure trigeminal stimulus in females with episodic migraine with aura (n = 13) and without aura (n = 15), to characterize the central nervous processing of these intranasal stimuli. Patients were tested in interictal state only. Data were analyzed in the time domain and in the time-frequency domain. Source reconstruction analysis was also performed.
Patients with aura had higher event-related potentials amplitudes for left-sided trigeminal and left-sided olfactory stimulations, and higher neural activity for right-sided trigeminal stimulation in brain areas related to trigeminal and visual processing. Following olfactory stimulations patients with aura displayed decreased neural activity in secondary olfactory structures compared to patients without aura. Oscillations in the low frequency bands (< 8 Hz) differed between patient groups.
Altogether this may reflect hypersensitivity to nociceptive stimuli in patients with aura relative to patients without aura. Patients with aura have a bigger deficit in engaging secondary olfactory-related structures, possibly leading to distorted attention and judgements towards odors. The cerebral overlap between trigeminal nociception and olfaction might explain these deficits.
越来越多的数据强调了嗅觉在偏头痛病理生理学中的重要性。然而，仅有少数研究评估了偏头痛大脑如何处理嗅觉刺激，而且在这方面几乎没有研究比较有先兆和无先兆偏头痛患者之间的差异。
本横断面研究在有先兆（n=13）和无先兆（n=15）女性偏头痛发作间期，使用 64 个电极记录事件相关电位，以了解这些鼻内刺激的中枢神经处理过程。仅在发作间期对患者进行测试。数据在时域和时频域中进行分析。还进行了源重建分析。
有先兆偏头痛患者的左侧三叉神经和左侧嗅觉刺激的事件相关电位幅度较高，右侧三叉神经刺激的大脑区域与三叉神经和视觉处理相关的神经活动较高。与无先兆偏头痛患者相比，有先兆偏头痛患者在嗅觉刺激后，二级嗅觉结构的神经活动减少。低频带（<8 Hz）的振荡在患者组之间存在差异。
总的来说，这可能反映了有先兆偏头痛患者对伤害性刺激的敏感性相对较高。有先兆偏头痛患者在参与二级嗅觉相关结构方面存在更大的缺陷，这可能导致对气味的注意力和判断扭曲。三叉神经痛觉和嗅觉之间的大脑重叠可能解释了这些缺陷。
