当前位置:生物帮 > 国内研究 > 神经科学 > 正文

Neurosci:中科院成都生物所方光战研究组发表仙琴蛙静息态脑网络研究成果

相关专题:
摘要 : 近日,《Neuroscience》期刊杂志在线发表了中国科学院成都生物研究所行为及其神经机理学科组的方光战研究组等的一篇研究论文,研究仙琴蛙静息态脑网络研究中获进展。

近日,《Neuroscience》期刊杂志在线发表了中国科学院成都生物研究所行为及其神经机理学科组的方光战研究组等的一篇研究论文,研究仙琴蛙静息态脑网络研究中获进展。博士生薛飞为论文第一作者,方光战研究员为论文通讯作者。

脑网络是当今脑科学研究的热点和难点之一。感觉、知觉、运动以及决策等诸多大脑功能都依赖脑网络实现。既往研究发现,当被试处于平躺且无任何外界刺激的状态下,其大脑不同区域之间依然保持自发的同步激活,形成静息态脑网络。这种静息态脑网络能够稳定相应功能态脑网络的连接以确保功能维持,同时还涉及诸如意识、记忆巩固和自我参照等重要的大脑功能。现有的静息态脑网络研究集中在人类、灵长动物和啮齿动物上,对低等脊椎动物(如蛙类)进行相应研究对理解大脑功能、物种进化等具有重要的科学意义。

研究组以仙琴蛙(BABIna daunchina)为对象,在其端脑和中脑左右两侧分别埋植电极,记录在不同活跃阶段下,个体处于静息状态时的脑电,通过格兰杰因果关系分析方法对不同脑区间的连接进行了探究。研究人员预测:(1)仙琴蛙存在偏侧性的静息态脑网络,并且与被动听觉功能相关联;(2)静息态脑网络存在性二型现象;(3)高活跃阶段的静息态脑网络的连接强度会高于低活跃阶段的连接强度。

结果显示:(1)在静息态下,仙琴蛙左侧中脑上行至两侧端脑的连接均强于右侧中脑的上行连接,而右侧端脑的传出连接显著强于其他脑区的传出连接。由于左侧中脑主导听觉感知,而右侧端脑主管注意调节,因此这种不对称性的脑网络可能反映了结构非对称性和注意调节共同作用的听觉偏侧性。(2)雌性个体左侧中脑的传出连接强于雄性个体。由于静息态网络连接强度与对应功能的工作效能成正相关,这一结果与雌性在繁殖期由于繁殖成本较高而须对外界刺激更为敏感的需求一致。(3)在不同活跃阶段,仙琴蛙的静息态脑网络并没有发生显著变化,说明仙琴蛙无论在活跃期还是在相对静止期,均对外界环境保持较高警觉,与其生存繁殖的需求相匹配。这些结果表明,仙琴蛙的静息态脑网络与其听觉感知功能相关联,并且具有性二型和不随活跃状态改变的稳定性。这些特征与仙琴蛙生存和繁殖的需求息息相关,且与哺乳动物类似,表明静息态脑网络是四足动物普遍存在的大脑特征之一。

原文链接:

Resting-state brain networks revealed by granger causal connectivity in frogs

原文摘要:

Resting-state networks (RSNs) refer to the spontaneous brain activity generated under resting conditions, which maintain the dynamic connectivity of functional brain networks for automatic perception or higher order cognitive functions. Here, Granger causal connectivity analysis (GCCA) was used to explore brain RSNs in the music frog (Babina daunchina) during different behavioral activity phases. The results reveal that a causal network in the frog brain can be identified during the resting state which reflects both brain lateralization and sexual dimorphism. Specifically (1) ascending causal connections from the left mesencephalon to both sides of the telencephalon are significantly higher than those from the right mesencephalon, while the right telencephalon gives rise to the strongest efferent projections among all brain regions; (2) causal connections from the left mesencephalon in females are significantly higher than those in males and (3) these connections are similar during both the high and low behavioral activity phases in this species although almost all electroencephalograph (EEG) spectral bands showed higher power in the high activity phase for all nodes. The functional features of this network match important characteristics of auditory perception in this species. Thus we propose that this causal network maintains auditory perception during the resting state for unexpected auditory inputs as resting-state networks do in other species. These results are also consistent with the idea that females are more sensitive to auditory stimuli than males during the reproductive season. In addition, these results imply that even when not behaviorally active, the frogs remain vigilant for detecting external stimuli.

doi:10.1016/j.neuroscience.2016.08.015

作者:方光战 点击:

    热门文章TOP