【作者】 张超；

【导师】 廖伟；

【作者基本信息】 电子科技大学 ， 电子信息（专业学位）， 2024， 硕士

【摘要】 人类大脑的发育和衰老是一个复杂且动态的过程。精神疾病和神经退行性疾病往往被视为大脑连接异常和衰老过程中病理学变化的结果。因此,刻画大脑发育轨迹对于早期诊断和治疗这些疾病至关重要。近年来,皮层梯度提供了一个独特的视角,通过探索大脑的多维连接梯度空间,来研究全脑空间分布模式。结合多个测量特征的脑结构和功能层级组织对于理解正常发育的连接体成熟过程具有重要意义,但其在整个生命周期中的标准生长轨迹尚不清楚。本研究利用了形态相似性网络来探究与年龄相关的多维梯度变化,包括全局级别、网络内和网络间的差异性。研究发现,大脑的全局结构变化遵循特定的分子组织模式,如谷氨酸和多巴胺神经递质。随着年龄的增加,网络内的差异性增大,反映了网络内部形态相似性的多样化增加。这种变化在初级感觉运动和高级联合皮层中尤为明显,它们对年龄相关的执行功能和认知灵活性起着调节作用。另一方面,随着年龄增大,次级感觉皮层与其他网络一起呈现出收缩趋势,这可能意味着它们在大脑三维结构中从边缘向更中心的位置移动。总体而言,本研究通过多维形态相似网络梯度空间丰富了对大脑形态特征随年龄变化的理解,并为理解这些变化如何影响认知功能提供了新的视角。进一步,本研究探索了功能相似网络的多维梯度与年龄的关系,包括功能梯度在整个生命周期的发育轨迹和功能分化模式。研究发现,随着年龄的增长,边缘网络、默认网络和背侧注意网络等大脑网络的功能相似性差异在梯度空间中呈现扩张趋势。这反映了功能性脑网络在发育过程中网络间的分化。另一方面,功能相似网络梯度随年龄分化模式遵循了宏观大脑结构属性和微观转录组学的大脑层级模式。此外,这种功能分化模式促进了信息从低层次感觉编码到高阶情感加工和支持抽象认知的发展。这些结果从多维功能相似网络梯度空间的视角,展现了大脑功能测量特征随年龄变化的发育轨迹和分化模式,对理解复杂的社会情感表现提供了的新见解。综上所述,本研究为探究形态和功能测量特征在整个生命周期的生长轨迹提供了参考,也为与年龄相关的网络间的发育和整合提供了新的认识与理解,同时也能够为解释大脑发育和认知之间的生理机制提供新的视角。更多还原

【Abstract】 The development and aging of the human brain is a complex and dynamic process.Mental illness and neurodegenerative diseases are often seen as the result of abnormal brain connectivity and pathological changes during aging.Therefore,characterizing the developmental trajectory of the brain is crucial for early diagnosis and treatment of these diseases.In recent years,the concept of cortical gradient has provided a unique perspective by exploring the multi-dimensional connectivity gradient space of the brain to study the spatial distribution patterns of the entire brain.The combination of multiple measurement features in brain structure and functional hierarchical organization has enlightening significance for understanding the maturation process of normal developmental connectors,but their standard growth trajectory throughout the entire lifecycle is still unclear.This study utilized morphological similarity networks to explore multidimensional gradient changes related to age,including differences at the global level,within the network,and between networks.Research has found that global structural changes in the brain follow specific molecular organizational patterns,such as neurotransmitters such as glutamate and dopamine.As age increases,the differences within the network increase,reflecting the diversity of morphological similarities within the network.This change is particularly evident in the primary motor and associative cortical networks,which play a regulatory role in age-related executive function and cognitive flexibility.On the other hand,as age increases,the secondary sensory cortex shows a contraction trend along with other networks,which may mean that they move from the edge to a more central position in the three-dimensional structure of the brain.Overall,this study enriches the understanding of changes in brain morphological features with lifespan through multidimensional gradient spaces,and provides a new perspective on how these changes affect cognition.Furthermore,this study explores the relationship between multidimensional gradients based on functional similarity networks and age,including the developmental trajectory and functional differentiation patterns of functional gradients throughout the entire lifecycle.Research has found that as age increases,the functional similarity differences of brain networks such as edge networks,default networks,and dorsal attention networks show an expanding trend in gradient space.This reflects the differentiation of functional brain networks between networks during development.On the other hand,the gradient differentiation pattern of functionally similar networks with age shares the same brain hierarchical organization as the macroscopic brain structural attributes and microscopic transcriptomics brain hierarchical patterns.In addition,this functional differentiation pattern promotes the development of information from lowlevel sensory encoding to higher-order emotional processing and supports abstract cognition.These results,from the perspective of multi-dimensional gradient space,demonstrate the developmental trajectory and differentiation patterns of brain function measurement features with age,providing new insights into understanding complex social and emotional expressions.In summary,this study provides a reference for studying the growth trajectory of morphological and functional measurement features throughout the entire lifecycle,and also provides new insights and understanding for the development and integration of agerelated networks.It can also provide a new perspective for explaining the biological mechanisms between brain development and cognition.更多还原