2020年4月29日，以色列魏茨曼科学研究所Noam Sobel和剑桥大学Anat Arzi合作在《自然》杂志发表论文，宣布他们发现因脑损伤而无意识的病人其嗅觉可以发出嗅信号意识。
嗅觉所处的大脑区域依赖于唤醒机制，因此，研究人员猜测嗅觉可以作为意识判断的生物标志物。
研究人员使用一种非言语、非任务依赖的测量方法，即嗅探反应来确定脑损伤患者的意识。通过测量与气味有关的嗅觉反应，研究人员获得了嗅觉功能敏感度的测量值。通过对严重脑损伤患者随时反复测量其嗅觉反应，研究人员发现在小组水平上，嗅觉反应可明显区分无反应状态和最低意识状态。
值得注意的是，在单一患者水平上，如果无意识患者有嗅觉反应，则可以确保未来意识的恢复。此外，嗅反应与长期生存率有关。这些结果凸显了嗅觉在人脑功能中的重要性，并提供了可靠的意识检测工具。
研究人员表示，严重脑损伤后，难以确定患者的意识状态，确定患者是否无意识或有最弱的意识并难以预测他们是否会康复。这些诊断和预后至关重要，因为它们决定了治疗策略（例如疼痛管理），并且可能成为生命周期决定的基础。但是，在确定脑损伤患者的意识状态时，其错误率高达40％。
附：英文原文
Title: Olfactory sniffing signals consciousness in unresponsive patients with brain injuries
Author: Anat Arzi, Liron Rozenkrantz, Lior Gorodisky, Danit Rozenkrantz, Yael Holtzman, Aharon Ravia, Tristan A. Bekinschtein, Tatyana Galperin, Ben-Zion Krimchansky, Gal Cohen, Anna Oksamitni, Elena Aidinoff, Yaron Sacher, Noam Sobel
Issue&Volume: 2020-04-29
Abstract: After severe brain injury, it can be difficult to determine the state of consciousness of a patient, to determine whether the patient is unresponsive or perhaps minimally conscious1, and to predict whether they will recover. These diagnoses and prognoses are crucial, as they determine therapeutic strategies such as pain management, and can underlie end-of-life decisions2,3. Nevertheless, there is an error rate of up to 40% in determining the state of consciousness in patients with brain injuries4,5. Olfaction relies on brain structures that are involved in the basic mechanisms of arousal6, and we therefore hypothesized that it may serve as a biomarker for consciousness7. Here we use a non-verbal non-task-dependent measure known as the sniff response8,9,10,11 to determine consciousness in patients with brain injuries. By measuring odorant-dependent sniffing, we gain a sensitive measure of olfactory function10,11,12,13,14,15. We measured the sniff response repeatedly over time in patients with severe brain injuries and found that sniff responses significantly discriminated between unresponsive and minimally conscious states at the group level. Notably, at the single-patient level, if an unresponsive patient had a sniff response, this assured future regaining of consciousness. In addition, olfactory sniff responses were associated with long-term survival rates. These results highlight the importance of olfaction in human brain function, and provide an accessible tool that signals consciousness and recovery in patients with brain injuries.
DOI: 10.1038/s41586-020-2245-5
Source: https://www.nature.com/articles/s41586-020-2245-5
Nature：《自然》，创刊于1869年。隶属于施普林格·自然出版集团，最新IF：69.504
官方网址：http://www.nature.com/
投稿链接：http://www.nature.com/authors/submit_manuscript.html
本期文章：《自然》：Online/在线发表
