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压力、睡眠与免疫力
许多人都曾有过因压力过大而辗转难眠的时候，但很少有人知道压力为何会引发失眠。最新的神经科学研究结果表明，大脑中那些能促进肾上腺皮质激素进行分泌的神经元与下视丘分泌素神经元有着紧密的联系。当前者受压力刺激被激活后，会一同激活后者，从而促使下视丘分泌素开始进行分泌，并将机体维持在觉醒状态。使用基因编辑技术抑制促肾上腺皮质激素神经元的活动后，压力信号就不会传输到下视丘分泌素神经元，有效的遏制了机体的兴奋状态。由促肾上腺皮质激素神经元所主导的这一回路不但会对睡眠产生影响还会对免疫系统造成破坏。在对这一回路进行刺激后，血液中特定免疫细胞的数量有了明显的下降，且其功能也出现了异常。这一机制的发现加深了我们对压力、睡眠、免疫力这三者关系的理解，并为将来人为干预手段的研发提供了重要的理论基础。
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自闭症患者脑内转运蛋白浓度与常人有显著差异
自闭症（ASD）是种神经精神类疾病，会严重影响一个人的社交技能和语言交流能力，并常伴有智力低下等情况。然而，直到目前为止，尚无一种特效药能针对其核心症状进行有效的治疗。在对正常人和ASD患者大脑内一种负责运输血清素的蛋白进行浓度检测后研究人员发现，ASD患者的大脑灰质和脑干中严重缺乏该类转运蛋白。血清素是一种重要的神经递质，参与多种生理、情感和认知功能的调控，并与大脑发育息息相关，而血清素转运蛋白的稀缺会直接导致大脑内血清素水平低下，从而对大脑的正常运作产生影响。行为测试结果也证实了血清素转运蛋白浓度与社会认知能力具有紧密的关联性，可见这种转运蛋白在ASD的发病中起着关键的作用。研究人员认为，对血清素系统的进一步研究将有望在未来为ASD特效药的研发提供一定的帮助。
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不同于成年人，儿童使用双侧大脑处理语言信息
解剖学、生理学和fMRI影像研究结果显示，人类的语言功能由左半脑负责，但事实上，小孩子无论是左半脑还是右半脑受到了损伤语言功能都会出现问题。这一悖论存在的原因是因为儿童和成人的大脑功能分布具有着显著的差异。在年幼的时候，左右大脑都会进行语言处理，而随着年龄的增长，语言功能才慢慢向左半脑集中。大脑的这种发展特性使小孩子在经历脑损伤后更不容易完全丧失语言能力，左半脑中语言处理区域的损伤可以靠右半脑来进行弥补，而成人的大脑在受到损伤后则不具备这种能力。
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反义寡核苷酸药物可抑制有毒蛋白在大脑中的积聚
TAR DNA结合蛋白43（TDP-43）是肌萎缩侧索硬化症（ALS）和额颞叶痴呆症（FTD）等神经性病变的病理学标记蛋白。这种蛋白负责mRNA前体的剪接，能帮助维持mRNA的稳定性，对细胞内RNA的转录尤为重要。而在ALS和FTD患者的大脑中，该蛋白会在细胞质中出现病理性的聚集，从而导致神经元出现功能性异常，甚至是死亡。这种聚集现象被发现是源自于C9orf72基因的突变。C9orf72基因的重复扩增会制造出一种简称为poly(GR)的有毒蛋白，而正是这种蛋白引发了一系列转运因子和核孔复合体的错位，并最终致使TDP-43蛋白在细胞内聚集成团。使用反义寡核苷酸药物抑制C9orf72基因的重复扩增就能减少poly(GR)的生成，并有效阻止TDP-43在细胞质中的积聚。研究人员称，他们将继续深入研究C9orf72基因和poly(GR)等有毒蛋白的关联性，这些机制的发现将为ALS和FTD等相关药物的开发带来莫大的帮助。
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Researchers pinpoint brain circuitry underlying dissociative experiences
Stanford scientists identified brain circuitry that plays a role in the mysterious experience called dissociation, in which people can feel disconnected from their bodies and reality.
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Reprogramming Brain Cells Enables Flexible Decision-Making
Humans, like other animals, have the ability to constantly adapt to new situations. Researchers at the Brain Research Institute of the University of Zurich have utilized a mouse model to reveal which neurons in the brain are in command in guiding adaptive behavior. Their new study contributes to our understanding of decision-making processes in healthy […]
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New Path to Neuron Regeneration After Spinal Cord Injury
Dynamic networks that specialize in the transmission of information generally consist of multiple components, including not only primary processors, like computers, for example, but also numerous support applications and services. The human nervous system is fundamentally very similar—neurons, like computers, process and transmit information, sending molecular signals through axons to other neurons, all of which […]
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Beyond Plaques and Tangles: Genetic Variation May Increase Risk of Cognitive Decline
A genetic variation in some people may be associated with cognitive decline that can’t be explained by deposits of two key proteins associated with Alzheimer’s disease, amyloid ß and tau, according to a study published in the September 16, 2020, online issue of Neurology®, the medical journal of the American Academy of Neurology. The genetic […]
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New gene implicated in neuron diseases
Motor neurons control movement, breathing, swallowing and speaking. Their death is a hallmark of progressive diseases such as spinal muscular atrophy and ALS, also known as Lou Gehrig’s disease. Understanding what can cause motor neurons to die is a key to developing precision treatments. Scientists are finding that the causes of motor neuron diseases are […]
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How Psychedelics Bind to Key Brain Cell Receptor
Psychedelic drugs such as LSD, psilocybin, and mescaline cause severe and often long-lasting hallucinations, but they show great potential in treating serious psychiatric conditions, such as major depressive disorder. To fully investigate this potential, scientists need to know how these drugs interact with brain cells at the molecular level to cause their dramatic biological effects. […]