Early Brain Development in One and Two Year Olds

描述（由申请人提供）：生命的头两年是出生后大脑发育最具活力，也可能是最关键的阶段。在大脑结构快速发育的同时，广泛的认知和运动功能也同样快速发展。尽管它对于理解正常发育和神经发育障碍（如精神分裂症和自闭症）的早期起源非常重要，但我们对这一关键时期人类大脑发育的了解却很少。虽然人们对使用MRI研究正常大脑发育的兴趣越来越大，但迄今为止的大多数研究都不包括生命的最初几年，因为这个年龄段儿童的图像采集和图像分析非常具有挑战性。我们已经解决了这些挑战，并开发了一个罕见的已经进行过新生儿MRI的前瞻性儿童队列。此外，我们还开发了新颖、尖端、最先进的图像分析技术，为研究生命头两年的大脑发育提供了强大的工具。我们是世界上少数几个已经开发出研究儿童早期大脑发育所需专业知识的组织之一。我们提出了一个纵向研究的大脑发育与MRI在正常的一岁和两岁的奥尔兹。这项研究将利用一个独特的大型队列，其中160多名儿童参加了目前资助的研究“高危儿童的早期大脑发育”，所有受试者都将在出生后2-4周进行产前超声检查和MRI检查，并在1岁和2岁时进行发育随访。使用新的自动分割和parcellation方法，我们将研究区域的变化，在灰色和白色物质量的头两年的生活。白色物质束，包括胼胝体和皮质脊髓束的发展将使用一种创新的定量纤维束成像的扩散张量成像（DTI）的属性和年龄特异性的DTI图谱，我们的小组开发的评估。这些白色物质束的扩散特性的成熟可以通过DTI和结构MRI的共配准直接与束的髓鞘形成相比较。在生命的头两年，区域大脑的生长将通过复杂的三维大脑绘图进行评估。将评估大脑区域和白色物质束发育轨迹的性别差异。最后，我们将研究儿童早期侧脑室形态的变化。这项拟议的研究将提供关于早期大脑发育的关键的、不可用的信息，并将直接提高我们对大脑正常发育的理解，为未来研究该年龄组的神经发育障碍提供基础。

DESCRIPTION (provided by applicant): The first two years of life is the most dynamic and perhaps the most critical phase of postnatal brain development. Concurrent with the rapid pace of structural brain growth is an equally rapid development of a wide range of cognitive and motor functions. In spite of its importance for understanding normal development and the early origins of neurodevelopment disorders such as schizophrenia and autism, our knowledge of human brain development in this crucial time period is minimal. While there has been growing interest in the study of normal brain development with MRI, most studies to date have not included the first few years of life because image acquisition and image analysis of children at this age is very challenging. We have addressed these challenges and have developed a rare prospective cohort of children who have already had neonatal MRIs.* In addition, we have developed novel and cutting edge, state-of-the-art image analysis techniques that provide powerful tools to study brain development in the first two years of life. We are one of the few groups in the world that has developed the expertise necessary to study very early brain development in children. We propose a longitudinal study of brain development with MRI in normal one and two year olds. This study will take advantage of a unique and large cohort of over 160 children who are enrolled in the currently funded study "Early Brain Development in High Risk Children" in which all subjects will have had prenatal ultrasounds and MRI's 2-4 weeks after birth and developmental follow-up at ages one and two years. Using novel automatic segmentation and parcellation methods, we will study regional changes in gray and white matter volumes over the first two years of life. The development of white matter tracts, including the corpus callosum and corticospinal tracts will be assessed using an innovative quantitative tractography of diffusion tensor imaging (DTI) properties and age-specific DTI atlases developed by our group. The maturation of diffusion properties in these white matter tracts can be directly compared to the myelination of the tracts through co-registration of DTI and structural MRIs. Regional brain growth over the first two years of life will be assessed with sophisticated three-dimensional brain mapping. Gender differences in the developmental trajectories of brain regions and white matter tracts will be assessed. Finally, we will study the changes in lateral ventricle shape in early childhood. The proposed study will provide critical, unavailable information about early brain development and will directly improve our understanding of brain normal development and provide the basis for future studies of neurodevelopment disorders in this age group.