Schwedt Todd J, Chong Catherine D, Chiang Chia-Chun, Baxter Leslie, Schlaggar Bradley L, Dodick David W
Mayo Clinic, Phoenix, AZ, USA
Mayo Clinic, Phoenix, AZ, USA.
Cephalalgia. 2014 Oct;34(12):947-58. doi: 10.1177/0333102414526069. Epub 2014 Mar 13.
The objective of this study was to identify brain regions having aberrant pain-induced activation in migraineurs, thereby gaining insight into particular aspects of pain processing that are atypical in migraineurs.
Functional magnetic resonance imaging assessed whole brain responses to painful heat in 24 adult episodic migraineurs who were at least 48 hours pain free and 27 healthy controls. Regions differentially activated in migraineurs compared to controls were identified. Activation intensities in these regions were correlated with headache frequency, number of migraine years, and time to next migraine attack.
Migraineurs had greater pain-induced activation of lentiform nucleus, fusiform gyrus, subthalamic nucleus, hippocampus, middle cingulate cortex, premotor cortex, somatosensory cortex, and dorsolateral prefrontal cortex, and less activation in precentral gyrus and superior temporal gyrus. There were significant correlations between activation strength and headache frequency for middle cingulate (r = 0.627, p = 0.001), right dorsolateral prefrontal cortex (r = 0.568, p = 0.004), left fusiform gyrus (r = 0.487, p = 0.016), left precentral gyrus (r = 0.415, p = 0.044), and left hippocampus (r = 0.404, p = 0.050) and with number of migraine years for left fusiform gyrus (r = 0.425, p = 0.038). There were no significant correlations between activation strength and time to next migraine attack.
The majority of regions with enhanced pain-induced activation in headache-free migraineurs participate in cognitive aspects of pain perception such as attending to pain and pain memory. Enhanced cognitive pain processing by migraineurs might reflect cerebral hypersensitivity related to high expectations and hypervigilance for pain.
本研究的目的是确定偏头痛患者中疼痛诱发激活异常的脑区，从而深入了解偏头痛患者疼痛处理过程中不典型的特定方面。
功能磁共振成像评估了24名至少48小时无疼痛的成年发作性偏头痛患者和27名健康对照者对热痛的全脑反应。确定了与对照组相比在偏头痛患者中差异激活的区域。这些区域的激活强度与头痛频率、偏头痛年数以及下次偏头痛发作的时间相关。
偏头痛患者在豆状核、梭状回、丘脑底核、海马体、中央扣带回皮质、运动前皮质、体感皮质和背外侧前额叶皮质有更强的疼痛诱发激活，而中央前回和颞上回的激活较少。中央扣带回（r = 0.627，p = 0.001）、右侧背外侧前额叶皮质（r = 0.568，p = 0.004）、左侧梭状回（r = 0.487，p = 0.016）、左侧中央前回（r = 0.415，p = 0.044）和左侧海马体（r = 0.404，p = 0.050）的激活强度与头痛频率之间存在显著相关性，左侧梭状回的激活强度与偏头痛年数之间存在显著相关性（r = 0.425，p = 0.038）。激活强度与下次偏头痛发作的时间之间无显著相关性。
在无头痛的偏头痛患者中，大多数疼痛诱发激活增强的区域参与疼痛感知的认知方面，如关注疼痛和疼痛记忆。偏头痛患者增强的认知性疼痛处理可能反映了与对疼痛的高期望和过度警惕相关的大脑超敏反应。
