Department of Behavioral Biology, Walter Reed Army Institute of Research, Silver Spring, MD 20910, USA.
J Clin Sleep Med. 2011 Oct 15;7(5 Suppl):S12-5. doi: 10.5664/JCSM.1344.
For those endeavoring to develop better methods of measuring/quantifying sleepiness, the "Holy Grail" is a measure that is maximally objective, completely unobtrusive, exquisitely sensitive, and absolutely specific (i.e., varies only as a function of sleepiness). By these criteria, physiological measures (e.g., based on brain activity such as EEG, fMRI, near-infrared spectroscopy, etc.) would appear to hold the most promise. However, from an operational standpoint, the utility of a sleepiness measure is derived not from its ability to sensitively reflect the brain's extant level of sleepiness per se, but from the implications that this level of sleepiness has for the individual's current and near-term ability to safely and efficiently perform operationally-relevant tasks. Thus, an ideal operationally-relevant sleepiness measure is one that is unobtrusively embedded in the actual operational task, and allows sleepiness-related performance deficits to be distinguished from performance deficits due to other causes. Toward this end, we have developed a PVT-derived metric that incorporates the entire distribution of responses within a PVT session, and reflects changes in the pattern of performance that can be used to identify and quantify "state instability"--the putative physiological state that specifically underlies sleepiness-induced performance deficits.
对于那些努力开发更好的睡眠评估方法的人来说，“圣杯”是一种最大限度地客观、完全不引人注目的、极其敏感和绝对特定的测量方法（即仅随困倦程度变化）。根据这些标准，生理测量（例如基于脑活动，如 EEG、fMRI、近红外光谱等）似乎最有前途。然而，从操作的角度来看，睡眠评估的实用性不是来自于其敏感地反映大脑当前困倦程度的能力，而是来自于这个困倦程度对个体当前和近期安全有效地执行操作相关任务的能力的影响。因此，一个理想的操作相关的困倦评估方法是一种不引人注目的嵌入到实际操作任务中的方法，并且可以区分与困倦相关的表现缺陷与由于其他原因导致的表现缺陷。为此，我们开发了一种源自 PVT 的度量标准，该标准纳入了 PVT 测试中的整个反应分布，并反映了性能模式的变化，这些变化可用于识别和量化“状态不稳定”——即睡眠诱导的表现缺陷的潜在生理状态。
