One function of spatial attention is to enable goal-directed interactions with the environment through the allocation of neural resources to motivationally relevant parts of space. Studies have shown that responses are enhanced when spatial attention is predictively biased towards locations where significant events are expected to occur. Previous studies suggest that the ability to bias attention predictively is related to posterior cingulate cortex (PCC) activation [Small, D.M., et al., 2003. The posterior cingulate and medial prefrontal cortex mediate the anticipatory allocation of spatial attention. Neuroimage 18, 633-41]. Sleep deprivation (SD) impairs selective attention and reduces PCC activity [Thomas, M., et al., 2000. Neural basis of alertness and cognitive performance impairments during sleepiness. I. Effects of 24 h of sleep deprivation on waking human regional brain activity. J. Sleep Res. 9, 335-352]. Based on these findings, we hypothesized that SD would affect PCC function and alter the ability to predictively allocate spatial attention. Seven healthy, young adults underwent functional magnetic resonance imaging (fMRI) following normal rest and 34-36 h of SD while performing a task in which attention was shifted in response to peripheral targets preceded by spatially informative (valid), misleading (invalid), or uninformative (neutral) cues. When rested, but not when sleep-deprived, subjects responded more quickly to targets that followed valid cues than those after neutral or invalid cues. Brain activity during validly cued trials with a reaction time benefit was compared to activity in trials with no benefit. PCC activation was greater during trials with a reaction time benefit following normal rest. In contrast, following SD, reaction time benefits were associated with activation in the left intraparietal sulcus, a region associated with receptivity to stimuli at unexpected locations. These changes may render sleep-deprived individuals less able to anticipate the locations of upcoming events, and more susceptible to distraction by stimuli at irrelevant locations.
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机译：空间注意力的一项功能是通过将神经资源分配给空间中与动机相关的部分，从而实现与环境的目标定向交互。研究表明，当将空间注意力预测性地偏向预计会发生重大事件的位置时，响应会增强。先前的研究表明，预测偏向注意力的能力与后扣带回皮层（PCC）的激活有关[Small，D.M.，et al。，2003.后扣带回和内侧前额叶皮层介导了空间注意的预期分配。 Neuroimage 18，633-41]。睡眠剥夺（SD）损害选择性注意力并降低PCC活性[Thomas，M.，et al。，2000.嗜睡过程中机敏性和认知能力受损的神经基础。 I. 24小时睡眠剥夺对唤醒人类区域性大脑活动的影响。 J.睡眠水库9，335-352]。基于这些发现，我们假设SD将影响PCC功能并改变预测性分配空间注意力的能力。七名健康的年轻成年人在正常休息和SD的34-36小时后进行了功能磁共振成像（fMRI），同时执行了一项任务，即注意力转移到对周围目标的反应之前，然后进行了空间信息化（有效），误导性（无效），或毫无信息的（中性）提示。休息时（而不是睡眠不足时），受试者对遵循有效线索的目标的反应比中立或无效线索后的目标更快。将具有反应时间受益的有效线索试验中的脑部活动与无益处的试验中的脑部活动进行比较。试验期间PCC的激活作用更大，正常休息后的反应时间有所改善。相反，在SD后，反应时间的好处与左顶壁沟的激活有关，左顶沟是一个在意外位置接受刺激的区域。这些变化可能会使缺乏睡眠的人无法预测即将发生的事件的位置，并且更容易受到无关位置刺激的干扰。
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