Iotchev Ivaylo Borislavov, Kubinyi Eniko
Department of Ethology, ELTE Eötvös Loránd University, Pázmány Péter sétány 1/C, Budapest, 1117, Hungary.
Biol Rev Camb Philos Soc. 2021 Jun;96(3):1021-1034. doi: 10.1111/brv.12688. Epub 2021 Feb 3.
Sleep spindles are phasic events observed in mammalian non-rapid eye movement sleep. They are relevant today in the study of memory consolidation, sleep quality, mental health and ageing. We argue that our advanced understanding of their mechanisms has not exhausted the utility and need for animal model work. This is both because some topics, like cognitive ageing, have not yet been addressed sufficiently in comparative efforts and because the evolutionary history of this oscillation is still poorly understood. Comparisons across species often are either limited to referencing the classical cat and rodent models, or are over-inclusive, uncritically including reports of sleep spindles in rarely studied animals. In this review, we discuss the emergence of new (dog and sheep) models for sleep spindles and compare the strengths and shortcomings of new and old models based on the three validation criteria for animal models - face, predictive, and construct validity. We conclude that an emphasis on cognitive ageing might dictate the future of comparative sleep spindle studies, a development that is already becoming visible in studies on dogs. Moreover, reconstructing the evolutionary history of sleep spindles will require more stringent criteria for their identification, across more species. In particular, a stronger emphasis on construct and predictive validity can help verify if spindle-like events in other species are actual sleep spindles. Work in accordance with such stricter validation suggests that sleep spindles display more universally shared features, like defining frequency, than previously thought.
睡眠纺锤波是在哺乳动物非快速眼动睡眠中观察到的阶段性事件。它们在当今记忆巩固、睡眠质量、心理健康和衰老的研究中具有重要意义。我们认为，我们对其机制的深入理解尚未穷尽动物模型研究的效用和需求。这既是因为一些主题，如认知衰老，在比较研究中尚未得到充分探讨，也是因为这种振荡的进化历史仍知之甚少。跨物种比较往往要么局限于参考经典的猫和啮齿动物模型，要么过于宽泛，不加批判地纳入对很少研究的动物睡眠纺锤波的报道。在这篇综述中，我们讨论了睡眠纺锤波新模型（狗和羊）的出现，并根据动物模型的三个验证标准——表面效度、预测效度和结构效度，比较了新旧模型的优缺点。我们得出结论，对认知衰老的关注可能决定比较睡眠纺锤波研究的未来，这一发展在对狗的研究中已初见端倪。此外，重建睡眠纺锤波的进化历史需要在更多物种中采用更严格的识别标准。特别是，更加强调结构效度和预测效度有助于验证其他物种中类似纺锤波的事件是否为真正的睡眠纺锤波。按照这种更严格验证标准开展的研究表明，睡眠纺锤波具有比以前认为的更多普遍共有的特征，如定义频率。
