BACKGROUND Psychogenic nonepileptic seizures (PNES) are a common and debilitating problem in patients with epilepsy. They can be virtually indistinguishable from epileptic seizures, demanding video-electroencaphalogram monitoring, which is costly and not widely available, for differential diagnosis. Specific functional brain correlates of PNES have not been demonstrated so far. We hypothesized that PNES and epileptic seizures have distinct brain activation patterns, assessed by functional neuroimaging during ictal events of both conditions. OBJECTIVE Compare ictal brain activation patterns of PNES and epileptic seizures using single-photon emission computerized tomography. METHODS We prospectively assessed brain functional activation using single-photon emission computerized tomography 99mTc-ethyl cysteinate dimer in 26 patients with PNES, confirmed by trained psychiatrists in epileptology, who had their seizures induced by provocative tests compared with 22 age- and sex-matched subjects with temporal lobe epilepsy who underwent prolonged intensive video-electroencaphalogram monitoring. RESULTS In PNES patients compared with temporal lobe epilepsy group, we found a consistent increase in regional cerebral blood flow in the right precuneus (Brodmann area 7; P = 0.003) and right posterior cingulate cortex (Brodmann area 31; P = 0.001), as well as a decrease in regional cerebral blood flow in the right amygdala (P = 0.027). CONCLUSIONS Activation of default model network brain areas and temporoparietal junction may be a distinct feature of ictal PNES and could be explained by a disruption between movement prediction input and sensory outcome. Such information mismatch might be the neurobiological underpinning of dissociative episodes.

中文翻译：

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心源性非癫痫和癫痫发作中的 ICTAL SPECT

背景 心因性非癫痫性癫痫发作 (PNES) 是癫痫患者常见且使人虚弱的问题。它们几乎无法与癫痫发作区分开来，需要视频脑电图监测，而后者成本高且不广泛用于鉴别诊断。迄今为止，尚未证实 PNES 的特定功能性大脑相关性。我们假设 PNES 和癫痫发作具有不同的大脑激活模式，在这两种情况的发作事件期间通过功能性神经影像学评估。目的 使用单光子发射计算机断层扫描比较 PNES 和癫痫发作的发作期脑激活模式。方法 我们使用单光子发射计算机断层扫描 99mTc-乙基半胱氨酸二聚体前瞻性评估了 26 名 PNES 患者的脑功能激活，由训练有素的癫痫学精神病学家证实，他们与 22 名年龄和性别匹配的颞叶癫痫受试者进行了长时间的强化视频脑电图监测相比，他们的癫痫发作是由激发试验引起的。结果 在 PNES 患者中，与颞叶癫痫组相比，我们发现右侧楔前叶（Brodmann 区域 7；P = 0.003）和右侧后扣带回皮层（Brodmann 区域 31；P = 0.001）的局部脑血流量持续增加，如以及右侧杏仁核的局部脑血流量减少（P = 0.027）。结论默认模​​型网络大脑区域和颞顶交界处的激活可能是发作期 PNES 的一个显着特征，可以通过运动预测输入和感觉结果之间的中断来解释。