Effects of experience on shared information across brains: Insights from blindness

该奖项是美国国家科学基金会社会、行为和经济科学（SBE）博士后研究奖学金（SPRF）项目和SBE认知神经科学项目的一部分。SPRF计划的目标是为学术界、工业界或私营部门和政府的科学事业准备有前途的早期职业博士级科学家。SPRF奖励包括在知名科学家的赞助下进行为期两年的培训，并鼓励博士后进行独立研究。美国国家科学基金会寻求促进科学界各阶层的科学家，包括那些未被充分代表的群体的科学家，参与其研究项目和活动；博士后阶段被认为是实现这一目标的一个重要的专业发展阶段。每个博士后必须解决各自学科领域的重要科学问题。在约翰霍普金斯大学的Marina Bedny， Janice Chen和Uri Hasson的赞助下，这个博士后奖学金奖支持一位早期职业科学家研究人类大脑的功能灵活性，以及个体在发展过程中的经历如何塑造皮层专业化。特别地，这个项目研究了盲人视觉皮层的神经可塑性和发育的原理。本研究采用功能神经成像技术研究不同盲人视皮层的神经元反应特性。为了研究盲人的视觉皮层是否对广泛的非视觉输入敏感，实验将测量盲人和视力正常的人在听自然的、叙事性的听觉刺激（如故事和电影片段）时的神经活动，这些听觉刺激包含不同程度的低水平、感官信息和高水平、抽象内容。这项研究有可能促进我们对神经可塑性和大脑发育机制的理解，这项工作的发现可能为未来的视觉障碍治疗提供信息。这项拟议的研究旨在通过调查大脑功能是如何被感官体验塑造的，来确定人类大脑的功能灵活性。人类大脑的枕叶通常支持视力正常的人的视觉处理，但对于天生没有视力的人来说，枕叶对触摸和声音有反应。然而，驱动这种可塑性的机制及其对人类大脑功能理论的影响仍然难以捉摸和有争议。为了探究盲人的视觉皮层是否对听觉输入的高水平、语义和低水平的感觉特征都敏感，本实验采用功能性神经成像来测量个体在听自然听觉刺激时的神经活动。此外，为了比较不同盲人的大脑，并将观察到的功能与视力正常的大脑联系起来，本研究采用了跨学科、脑对脑的神经成像分析。第一个分析将探讨视觉皮层是否在不同的盲人个体中表现出可靠的相似反应。为了进一步表征盲人视觉皮层的反应，第二个分析测试了盲人视觉皮层是否执行与正常大脑中观察到的功能网络相似的计算。第三个分析是通过比较先天失明和成年后失明的人的视觉皮层功能，测试早期生活经历如何影响大脑发育。这项工作有可能对大脑发育理论做出重要贡献，特别是关于发育时间过程和皮层功能专门化的潜力。在失明之外，这些研究可以作为理解经验因素在发育过程中如何驱动大脑可塑性的一般模型。这些发现也将推进我们对神经组织的功能如何在整个生命周期中得到优化或重新利用的认识。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

This award was provided as part of NSF's Social, Behavioral and Economic Sciences (SBE) Postdoctoral Research Fellowships (SPRF) program and SBE's Cognitive Neuroscience program. The goal of the SPRF program is to prepare promising, early career doctoral-level scientists for scientific careers in academia, industry or private sector, and government. SPRF awards involve two years of training under the sponsorship of established scientists and encourage Postdoctoral Fellows to perform independent research. NSF seeks to promote the participation of scientists from all segments of the scientific community, including those from underrepresented groups, in its research programs and activities; the postdoctoral period is considered to be an important level of professional development in attaining this goal. Each Postdoctoral Fellow must address important scientific questions that advance their respective disciplinary fields. Under the sponsorship of Marina Bedny, Janice Chen, and Uri Hasson at Johns Hopkins University, this postdoctoral fellowship award supports an early career scientist studying the functional flexibility of the human brain, and the ways in which an individual's experiences during development can shape cortical specialization. In particular, this project investigates the principles that govern neural plasticity and development of the visual cortex in blind people. The proposed research uses functional neuroimaging to study the neuronal response properties of the visual cortices across different blind individuals. To investigate whether the visual cortices of blind people are sensitive to a wide range of non-visual input, the proposed experiments will measure neural activity while blind and sighted individuals listen to naturalistic, narrative auditory stimuli, such as stories and movie clips, that contain varying degrees of low-level, sensory information versus high-level, abstract content. This research has the potential to advance our understanding of the mechanisms of neural plasticity and brain development, and the findings from this work may inform future treatments of visual impairments.The proposed research aims to determine the functional flexibility of the human brain by investigating how brain function is shaped by sensory experience. The occipital lobes of the human brain, which typically support visual processing in sighted individuals, respond to touch and sound in individuals who are born without vision. However, the mechanisms driving this plasticity and its implications for theories of human brain function remain elusive and disputed. To probe whether the visual cortex of blind individuals is sensitive to both high-level, semantic and low level, sensory features of auditory input, these experiments employ functional neuroimaging to measure neural activity while individuals listen to naturalistic auditory stimuli. In addition, to compare the brains of different blind individuals, and to relate the observed functions to the sighted brain, the proposed research applies inter-subject, brain-to-brain neuroimaging analyses. The first analysis will address whether the visual cortex exhibits reliably similar response profiles across different blind individuals. To further characterize responses in blind visual cortex, the second analysis tests whether blind visual cortex performs similar computations to functional networks that are observed in the sighted brain. The third analysis tests how early life experience shapes brain development by comparing the functions of visual cortex in individuals who are born blind to those who lost their vision in adulthood. This work has the potential to make important contributions to theories of brain development, particularly regarding the developmental time course and the potential for functional specialization in cortex. Outside of blindness, these studies may serve as a general model for understanding how experiential factors drive brain plasticity during development. Such findings will also advance our knowledge of how the functions of neural tissue can be optimized or re-purposed across the lifespan.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.