Ferrara M, Bertini M
Department of Psychology, University of Rome La Sapienza, Italy.
Sleep. 2000 Sep 15;23(6):801-11.
The potential impact of sleep inertia on measures of voluntary oculomotor control have been surprisingly neglected. The present study examined the effects of 40 hours of sleep deprivation on saccadic (SAC) and smooth pursuit (SP) performance, attentional/visual search performance (Letter Cancellation Task, LCT) and subjective sleepiness (Sleepiness Visual Analog Scale, SVAS) recorded immediately after awakening. Standard polysomnography of nine normal subjects was recorded for 3 nights (1 adaptation, AD; 1 baseline, BSL; 1 recovery, REC); BSL and REC were separated by a period of 40 h of continuous wakefulness, during which subjects were tested every two hours. Within 30 s of each morning awakening, a test battery (SAC, SP, LCT, SVAS) was administered to subjects in bed. For data analysis, mean performance obtained during the day preceding the sleep deprivation night was considered as "Diurnal Baseline" and compared to performance upon awakening from nocturnal sleep. As a consequence of sleep deprivation, SWS percentage was doubled during REC. Saccade latency increased and velocity decreased significantly upon awakening from REC as compared to the other three conditions (Diurnal baseline, AD awakening, BSL awakening); accuracy was unaffected. As regards SP, phase did not show any impairment upon awakening, while velocity gain upon awakening from REC was significantly lower as compared to the other conditions. Finally, number of hits on LCT upon awakening from REC was significantly lower and subjective sleepiness higher as compared to Diurnal Baseline. It is concluded that 40 h of sleep deprivation significantly impaired performance to SAC and SP tasks recorded upon awakening from recovery sleep. This performance worsening is limited to the measures of speed, while both SAC accuracy and SP phase do not show a significant decrease upon awakening. Since saccadic velocity has recently been found to negatively correlate with simulator vehicle crash rates, it is suggested that the adverse effects of sleep deprivation on sleep inertia magnitude should be avoided by any personnel who may have to perform critical tasks involving high oculomotor control immediately after awakening.
睡眠惯性对自主眼球运动控制指标的潜在影响一直令人惊讶地被忽视了。本研究考察了40小时睡眠剥夺对觉醒后即刻记录的扫视（SAC）和平滑跟踪（SP）表现、注意力/视觉搜索表现（字母取消任务，LCT）以及主观嗜睡程度（嗜睡视觉模拟量表，SVAS）的影响。对9名正常受试者进行了3晚的标准多导睡眠图记录（1晚适应期，AD；1晚基线期，BSL；1晚恢复期，REC）；BSL和REC之间间隔40小时持续清醒，在此期间每两小时对受试者进行测试。每天早晨觉醒后30秒内，在床上对受试者进行一组测试（SAC、SP、LCT、SVAS）。数据分析时，将睡眠剥夺前一天白天获得的平均表现视为“日间基线”，并与夜间睡眠觉醒后的表现进行比较。由于睡眠剥夺，REC期间慢波睡眠百分比翻倍。与其他三种情况（日间基线、AD觉醒、BSL觉醒）相比，从REC觉醒时扫视潜伏期延长且速度显著降低；准确性未受影响。至于SP，觉醒时相位未显示任何损害，而与其他情况相比，从REC觉醒时速度增益显著降低。最后，与日间基线相比，从REC觉醒时LCT的命中次数显著减少且主观嗜睡程度更高。得出的结论是，40小时睡眠剥夺显著损害了从恢复睡眠觉醒后记录的SAC和SP任务的表现。这种表现恶化仅限于速度指标，而SAC准确性和SP相位在觉醒时均未显示显著下降。由于最近发现扫视速度与模拟器车辆碰撞率呈负相关，建议任何可能在觉醒后立即执行涉及高眼球运动控制的关键任务的人员应避免睡眠剥夺对睡眠惯性程度的不利影响。
