Department of Neurosurgery, The Methodist Neurological Institute, Houston, TX, USA.
Neuropsychologia. 2013 Jun;51(7):1370-6. doi: 10.1016/j.neuropsychologia.2012.07.004. Epub 2012 Jul 16.
Executive dysfunction occurs in a variety of patients who have sustained damage to the frontal lobes. In individuals with frontal lobe epilepsy (FLE) or after unilateral frontal lobe resection (FLR), a unique neuropsychological profile linking executive functions (EF) with the frontal lobe has been elusive, with conflicting findings in the literature. Some studies show greater risk of executive impairment with left-sided FLE or FLR, while others report greater risk for right-sided patients. Some studies report no relationship between FLE and EF impairment, while others show EF impairment regardless of side of seizure foci or surgery. In patients with temporal lobe epilepsy, executive dysfunction is associated with depressed mood possibly reflecting disruption of cortical-limbic pathways and/or frontal-striatal circuitry. Although not previously examined, depression level may affect executive functioning in those with FLE or FLR. We hypothesized that FLE patients with poor mood state would show greater executive dysfunction than FLE patients without poor mood state. The relationship among EF, side of surgery and depressed mood before and 8 months after unilateral FLR was evaluated in 64 patients using validated measures of EF and mood state (Beck Depression Inventory-II). Results indicated that individuals with depressed mood before surgery had greater difficulty on a task of mental flexibility compared to patients without preoperative depressed mood. Further, individuals with depressed mood before surgery had significant increases in perseverative responding and completed fewer categories on a card-sorting task after surgery compared to patients without preoperative depressed mood. Regression analyses showed that among side of surgery, seizure freedom status after surgery and depression status, only pre-surgical depression status explained a significant amount of variance in executive functioning performance after surgery. Results suggest that clinically elevated depressive symptoms before surgery are a risk factor for moderate declines in EF after surgery. Results may be attributable to reduced cognitive reserve in patients with depressive symptoms, or may reflect a common cause attributable to damage to unilateral dorsal and ventral lateral frontal lobe.
执行功能障碍发生在各种因额叶损伤而导致的患者中。在患有额叶癫痫（FLE）或单侧额叶切除（FLR）的个体中，将执行功能（EF）与额叶联系起来的独特神经心理学特征一直难以捉摸，文献中的研究结果存在冲突。一些研究表明，左侧 FLE 或 FLR 患者的执行功能障碍风险更高，而其他研究则报告右侧患者的风险更高。一些研究报告 FLE 与 EF 损伤之间没有关系，而其他研究则表明无论癫痫灶或手术的哪一侧，EF 损伤都会发生。在颞叶癫痫患者中，执行功能障碍与抑郁情绪有关，这可能反映了皮质边缘通路和/或额纹状体回路的中断。虽然以前没有检查过，但抑郁水平可能会影响 FLE 或 FLR 患者的执行功能。我们假设情绪状态不佳的 FLE 患者的执行功能障碍会比情绪状态良好的 FLE 患者更为严重。使用 EF 和情绪状态的验证测量工具（贝克抑郁量表 II）评估了 64 名患者手术侧、术前和单侧 FLR 后 8 个月的 EF 与抑郁情绪之间的关系。结果表明，术前有抑郁情绪的个体在心理灵活性任务上比术前没有抑郁情绪的个体更难以完成任务。此外，与术前没有抑郁情绪的患者相比，术前有抑郁情绪的个体在手术后持续反应中存在显著增加，并且在卡片分类任务中完成的类别较少。回归分析表明，在手术侧、手术后癫痫发作情况和抑郁状况中，只有术前抑郁状况能够解释手术后执行功能表现的显著差异。结果表明，术前临床显著的抑郁症状是手术后 EF 中度下降的一个风险因素。结果可能归因于有抑郁症状患者的认知储备减少，或者可能反映了单侧背外侧和腹外侧额叶损伤的共同原因。
