目的:神经影像学研究揭示了额叶(FL)对记忆编码的贡献。因此,记忆障碍记录在额叶癫痫(FLE)。尽管如此,对这种损伤的结构或功能相关性知之甚少。特别是,FLE记忆编码过程中大脑活动功能变化的物质特异性尚不清楚。
方法:我们比较了24名接受术前评估的FLE患者(15名右侧)与30名健康对照者的记忆fMRI学习场景范式,面孔,和单词,然后是扫描仪外识别任务,以及有关其颞叶(mTL)体积的信息。我们还解决了FLE侧向化和性能水平的影响(正常与低)。
结果:FLE患者的记忆力较差,左侧海马体积大于对照组。数量增加似乎,然而,与记忆性能无关,甚至功能失调。Further,FLE患者的功能变化在场景和面部为右侧,在言语为双侧。详细来说,在人脸编码期间,FLE患者有,不管他们的表现水平如何,减少MTL激活,而在场景和单词编码期间,只有低表现的FLE患者的mTL降低,FL激活降低。在FLE患者中,完整的言语记忆表现与较高的右额叶激活相关,但在对照组中却没有。
结论:药物抗性FLE对mTL具有明显的功能和结构影响。效果因编码材料和患者表现水平而异。因此,除了FL的直接影响,FLE中的记忆障碍可能在很大程度上是由于FL网络中断引发的功能mTL变化。
结论:额叶癫痫(FLE)患者可能患有记忆障碍。因此,我们要求患者在接受MRI扫描时执行一项记忆任务,以调查学习期间大脑激活的可能变化.FLE患者在学习过程中表现出大脑激活的变化以及颞叶内侧的结构变化,这是一个与学习特别相关的大脑区域,但不是FLE癫痫发作的起源。我们得出的结论是,FLE会导致广泛的变化,从而导致FLE患者的记忆障碍。
OBJECTIVE: Neuroimaging studies reveal frontal lobe (FL) contributions to memory encoding. Accordingly, memory impairments are documented in frontal lobe epilepsy (FLE). Still, little is known about the structural or functional correlates of such impairments. Particularly, material specificity of functional changes in cerebral activity during memory encoding in FLE is unclear.
METHODS: We compared 24 FLE patients (15 right-sided) undergoing presurgical evaluation with 30 healthy controls on a memory fMRI-paradigm of learning scenes, faces, and words followed by an out-of-scanner recognition task as well as regarding their mesial temporal lobe (mTL) volumes. We also addressed effects of FLE lateralization and performance level (normal vs. low).
RESULTS: FLE patients had poorer memory performance and larger left hippocampal volumes than controls. Volume increase seemed, however, irrelevant or even dysfunctional for memory performance. Further, functional changes in FLE patients were right-sided for scenes and faces and bilateral for words. In detail, during face encoding, FLE patients had, regardless of their performance level, decreased mTL activation, while during scene and word encoding only low performing FLE patients had decreased mTL along with decreased FL activation. Intact verbal memory performance was associated with higher right frontal activation in FLE patients but not in controls.
CONCLUSIONS: Pharmacoresistant FLE has a distinct functional and structural impact on the mTL. Effects vary with the encoded material and patients\' performance levels. Thus, in addition to the direct effect of the FL, memory impairment in FLE is presumably to a large part due to functional mTL changes triggered by disrupted FL networks.
CONCLUSIONS: Frontal lobe epilepsy (FLE) patients may suffer from memory impairment. Therefore, we asked patients to perform a memory task while their brain was scanned by MRI in order to investigate possible changes in brain activation during learning. FLE patients showed changes in brain activation during learning and also structural changes in the mesial temporal lobe, which is a brain region especially relevant for learning but not the origin of the seizures in FLE. We conclude that FLE leads to widespread changes that contribute to FLE patients\' memory impairment.