Object, face, body and scene representations in the human brain

人脑中的物体、面部、身体和场景表征

• 批准号: 8939999
• 负责人: Christopher Baker
• 金额: $ 76.06万
• 依托单位: NATIONAL INSTITUTE OF MENTAL HEALTH
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/8939999
• 关键词: Accounting; Behavior assessment; Behavioral; Body part; Brain; Brain region; Categories; Cattle; Color; Complex; Eye; Face; Functional Magnetic Resonance Imaging; Goals; Hand; Human; Image; Knowledge; Learning; Leg; Light; Measures; Mental Health; Nature; Off-Road Motorbikes; Participant; Pattern; Perception; Process; Property; Protocols documentation; Research; Retina; Role; Semantics; Sensory; Signal Transduction; Social Behavior; Stimulus; Trees; United States National Academy of Sciences; Visual; Visual Fields; Visual Perception; Work; experience; falls; foot; insight; interest; nervous system disorder; physical property; preference; receptive field; visual information; visual process; visual processing; visual stimulus

The goal of this research is to understand how we see what we see: how does the brain analyze the light falling on the retina of the eye to encode a world full of objects, people and things? During the past year we have continued to investigate 1) the interaction between bottom up (sensory driven) and top-down (internally driven) processing in the brain, focusing on the impact of task or behavioral goals, and 2) perception of complex visual stimuli, focusing most recently on visual scenes. 1) Interaction between bottom up and top down processing Our visual perception is the product of an interaction between bottom-up sensory information and top-down, internally generated signals guiding interpretation of the input and reflecting our prior knowledge and intent. Different tasks require different types of visual information to be extracted from visual stimuli, depending on the behavioral goals of the observer. We have been investigating how the representations of complex visual stimuli vary according to the task a participant is performing. We presented participants with images of every day objects (e.g. cow, tree, motorbike) and asked them to respond to simple questions sucg as whether the object is big or small?, manmade or natural? (Harel et al, 2014, Proceedings of the National Academy of Sciences). First, we found that we could decode the task was performing on a given visual object from activity patterns in multiple regions throughout the brain. Further, we found a strong distinction between tasks that emphasized physical properties of the visual stimuli (e.g. color) and tasks that emphasized conceptual properties (e.g. real-world size). Second, we are now extending this work to visual scenes. Previously, we found that scene representations in a region of the brain thought to be critical for scene recognition primarily reflect the spatial properties of scenes (e.g. whether they are open or closed) and not the semantic properties (i.e. scene category, such as office or beach). In our current work, we are investigating how these representations change according to task, by asking participants to focus on particular aspects of the scenes presented. 2) Perception of real world scenes Real-world scenes are incredibly complex and heterogeneous, yet we are able to identify and categorize them effortlessly. While prior studies have identified several brain regions that appear to be specialized for scene processing, it remains unclear exactly what the precise roles of these different regions are. Building on a general framework for visual processing in the brain we recently proposed, we are currently investigating the extent to which basic properties of these regions (e.g. preference for particular parts of the visual field, size of receptive fields) account for their role in scene processing and how these properties relate to behavioral assessments of visual scenes. Elucidating how the brain enables us to recognize objects, scenes, faces and bodies provides important insights into the nature of our internal representations of the world around us. Understanding these representations is vital in trying to determine the underlying deficits in many mental health and neurological disorders.

这项研究的目的是了解我们如何看待我们看到的东西：大脑如何分析眼睛视网膜上的光，以编码一个充满物体，人和事物的世界？ 在过去的一年中，我们继续研究1）自下而上的（感觉驱动）与大脑中自上而下的（内部驱动）处理之间的相互作用，重点关注任务或行为目标的影响，2）感知复杂的视觉刺激，重点是最近的视觉场景。 1）自下而上的上下处理之间的互动 我们的视觉感知是自下而上的感觉信息与自上而下的，内部生成的信号指导输入的解释并反映我们先前的知识和意图之间的相互作用的产物。 不同的任务需要从视觉刺激中提取不同类型的视觉信息，具体取决于观察者的行为目标。我们一直在研究参与者执行的任务，复杂的视觉刺激的表示如何变化。 我们向参与者介绍了每天的物体（例如牛，树木，摩托车）的图像，并要求他们回答简单的问题，例如物体是大还是小？，人造还是自然？ （Harel等人，2014年，美国国家科学院论文集）。 首先，我们发现我们可以解码该任务是在整个大脑多个区域的活动模式上对给定的视觉对象执行的。此外，我们发现了强调视觉刺激物理特性（例如颜色）的任务和强调概念属性（例如现实世界大小）的任务。 其次，我们现在将这项工作扩展到视觉场景。以前，我们发现大脑区域中的场景表示对于场景识别至关重要，主要反映了场景的空间特性（例如它们是开放的还是封闭的），而不是语义属性（即场景类别，例如办公室或海滩）。在当前的工作中，我们正在调查这些表示形式如何根据任务发生变化，要求参与者专注于所介绍的场景的特定方面。 2）对现实世界的感知 现实世界的场景非常复杂和异质，但我们能够轻松地识别和归类。虽然先前的研究已经确定了似乎专门用于场景处理的几个大脑区域，但尚不清楚这些不同区域的确切作用确切。 在我们最近提出的大脑视觉处理的一般框架的基础上，我们目前正在研究这些区域的基本特性（例如，对视野的特定部分的偏爱，接收场的偏爱）解释了它们在场景处理中的作用以及这些属性与视觉场景的行为评估之间的关系。 阐明大脑如何使我们能够识别对象，场景，面部和身体，为我们周围世界内部表现的本质提供了重要的见解。理解这些表征对于试图确定许多心理健康和神经系统疾病的潜在缺陷至关重要。