全睡眠剥夺30小时后不同时长恢复性小睡对青年男性睡眠惯性的影响

Effects of sleep inertia on cognitive performance following different time course naps after 30 hours sleep deprivation in healthy men

目的研究全睡眠剥夺（30h）后不同时长恢复性小睡的睡眠结构差异以及对随后睡眠惯性期认知能力的影响。方法选择10名健康男性志愿者，年龄（20．8±2．1）岁，进行自身前后对照I生试验研究。试验分为2个阶段，第一阶段是30h全睡眠剥夺后进行20min小睡（20min小睡组），第二阶段为30h睡眠剥夺后进行2h小睡（2h小睡组），两个阶段试验之间正常作息1周。小睡期间进行多导睡眠图（PSG）监测，观察睡眠进程及睡眠结构。分别在唤醒后5、30、50min进行认知功能测试，包括持续注意试验、Stroop词色干扰试验、数字相加试验。结果（1）睡眠剥夺后，两组均可见睡眠潜伏期缩短。20min小睡组的睡眠结构主要为非快速眼球运动睡眠中的1期和2期；而与健康人睡眠结构比较，2h小睡组睡眠结构中慢波睡眠比例增加，快速眼球运动睡眠比例减少。（2）睡眠惯性对认知行为学的影响：与基线值比较，两组在不同时长恢复性小睡后睡眠惯性期均出现持续注意力、选择注意力、计算力的下降[CPT正确反应数（次／3min）：371．8±21．3与334．4±22．4、373．2±19．0与323．7±23．8，t=10．443、7．774，均P〈0．01；Stroop词色干扰试验干扰分（分）：20．3±1．5与17．3±1．0、21．5±0．8与16．1-1-1．4，t=8．478、4．934，均P〈0．05；数字相加试验完成时间（s）：222．2±13．2与266．6±23．7、226．3±10．9与267．6±23．4，t=5．748、6．685，均P〈0．01]。与20min小睡组比较，2h小睡组虽然在睡眠惯性早期（唤醒后5rain）认知功能受损更重，但恢复更快（唤醒后30min即完全恢复）。结论（1）青年男性在经历30h全睡眠剥夺后不同时长的恢复性小睡，在其睡眠结构、唤醒时的睡眠分期上差异有统计学意义。（2）恢复性小睡后睡眠惯性对持续注意力、选择注意力、计算力等认知功能产生负性影响。（3）过分片段化的睡眠并不利于机体的恢复。

Objective To study the effects of sleep inertia （SI） of different time course sleeps on sleep stages and cognitions in healthy men after 30 h sleep deprivation, and also to investigate the mechanism of cognitive functions impairment in sleep inertia stages and the influential factors of sleep inertia. Methods Ten healthy men （age, （20. 8± 2. 1 ） years） participated in the program. The program was divided into 2 stages. First, participants attended a series of tests after 20 rain nap（20 min nap group） after 30 h sleep deprivation. The testing series included 3 parts： the continuous performance task,the Stroop Tests, and the Addition Tests. The series of tests were done 3 times immediately after the volunteers were awoken and each lasted about 15 minutes with an interval of 10 minutes between each test. The polysomnogram （PSG） was recorded during the nap. The following 7 days was set as washinz-out oeriod to ensure a complete recovery. Participants repeated the similar processes with 2 h nap（2 h nap group） instead of 20 min nap. The cognitive performance of each group was compared with each other along with the best cognitive performance in awakening to estimate whether or not the cognitive abilities regained the normal condition. Results （ 1 ） Sleep latency became shortened in both groups after 30 h sleep deprivation. There were no slow wave sleep （SWS） and rapid eye movement sleep （REM） sleep stages in the 20 min naps, while the percentage of SWS was increased and percentage of REM declined in 2 h naps. （2） In the early of SI （5 min after awaking）, cognitive tasks showed that the abilities of continuous attention ,selected attention and addition ability were all impaired （ continuous performance task： （ 371.8± 21.3 ） times/3 min vs （334. 4±22. 4） times/3 min, （373.2 ± 19. 0） times/3 min vs （323.7 ±23.8） times/3 min,t = 10. 443, 7.774 ,both P 〈0. 01 ; Stroop tests ： （ 20. 3 ± 1.5 ） points vs （ 17.3 ± 1.0 ） points, （ 21.5 ± 0. 8 ） points vs （ 16. 1 ± 1.4 ） points, t = 8. 478,4. 934, both P 〈 0. 05 ; Addition Tests ： （ 222. 2 ± 13.2 ） s vs （ 266. 6 ± 23.7） s, （226. 3 ± 10. 9） s vs （267.6± 23.4） s, t = 5. 748,6. 685, both P 〈 0. 01 ）. The cognitive functions impairments of 2 h nap group were more severe at the initiation of sleep inertia, but regained the normal condition more quickly. Different cognitive tasks recovered at different speeds. The dispersion of SI needed 30 min. Conclusions （1） There are difference in the sleep construction and awaked sleep stage between 20 min nap and 2 h nap groups. （2） SI exerts negative influences on cognitive performances of continuous attention, selected attention and addition after sleep deprivation. Many factors may influence the dispersion of SI, including sleep debt, compensation of sleep debt and others. （3） Fragments of sleep are unfavorable to the recovery of body.