睡眠呼吸暂停综合征患者工作记忆损害的事件相关电位脑电地形图研究

Central executive dysfunction in patients with obstructive sleep apnea syndrome: an event-related potential topographic study

目的 用事件相关电位 (ERP)脑电地形图技术 ,研究睡眠呼吸暂停综合征 (OSAS)睡眠间断性低血氧对工作记忆损害机制。方法 采用探针提取方法并加以改良。轻、重症患者各 12例 ;同期设 2 0名正常对照者。结果 ERP结果显示 ,对照组辨异效应主要分布于右额 [F4 ,(2 .2± 2 .7)μV]及枕部 [O1,(0 .8± 3.5 ) μV ;O2 ,(0 .7± 3.5 ) μV],辨同效应则以顶部为著 [P3,(7.0± 3.0 ) μV ;P4 ,(6 .9± 3.1) μV ]。轻症患者前额部辩异效应损害明显 [F4 ,(5 .0± 4 .5 ) μV ;F3,(6 .0± 4 .5 ) μV ;P <0 .0 1],而重症组辨异及辨同效应均受损 [F3,(5 .3± 2 .4 ) μV ;F4 ,(4.9± 3.1) μV ;P3,(3.6± 3.5 )μV ;P4 ,(4.6± 2 .7) μV ;P <0 0 5 ]。脑电地形图与上述结果一致。 结论 OSAS患者前额ERP辨异效应的变化反映了中央执行系统功能对缺氧性损害十分敏感。

Objective To evaluate the early effect of hypoxemia on central executive function of working memory.Methods 24 patients with obstructive sleep apnea syndrome (OSAS) and 20 healthy matching controls were studied in probe retrieval task.Results In control group,both the low and high conflict identification tasks elicited the N270 component with right prefrontal [F4,(2.2±2.7) μV]and posterior [P3,(7.0±3.0) μV; P4,(6.9 ± 3.1) μV] distribution. N430 was elicited in high conflict condition with right hemispheric lateralization. The positive component,P300( 300～400 ms) distributed remarkably at parietal scalp[P3,(7.0±3.0) μV; P4,(6.9±3.1) μV]was elicited only in identity identification task. The N270 was significantly decreased in the frontal regions in mild OSAS patients [F4,(5.0 ± 4.5) μV]; F3,(6.0±4.5) μV] in comparison with the controls( P <0.01). In contrast,the positive component was significantly decreased in only OSAS B groups in comparison with the controls( P <0.01). In contrast,the positive component was significantly decreased in only OSAS B groups [P3,(3.6±3.5) μV;P4,(4.6±2.7) μV]( P <0.05). Conclusion The disturbances of the ERP conflict effects over prefrontal regions indicate that the central executive of working memory is more vulnerable to the chronic nocturnal intermittent hypoxemia.