Stimulus and context effects on perception

刺激和环境对感知的影响

• 批准号: RGPIN-2015-06787
• 负责人: Sekuler, Allison
• 金额: $ 2.91万
• 依托单位: McMaster University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2017
• 资助国家: 加拿大
• 起止时间: 2017-01-01 至 2018-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=631088
• 关键词: Stimulus; context; effects; perception

One of the main goals of the visual system is to recognize objects so that we may interact with them appropriately. Although recognition of people, places, and things typically appears effortless and instantaneous, perception takes measurable time, and the visual system must overcome tremendous obstacles for recognition to occur. For example, various elements of the raw images that reach our eyes must be organized appropriately, so that we perceive coherent, meaningful, complete objects rather than inappropriately segmented, confusing scenes. Given the complexity of the recognition process, it is not surprising that we have relatively little understanding of the neural mechanisms underlying recognition. The objective of the current proposal is to advance that understanding, particularly with respect to the role of stimulus and contextual information on the visual perception of faces. Over the past decade, my lab has refined a number of psychophysical and electrophysiological techniques that enable us to address these issues at different levels than previously possible. The current proposal extends this work, especially with respect to understanding the neural mechanisms underlying face recognition, and branches into new areas examining how aspects of visual perception are altered by contextual cues and experience. Although my work relies on behavioural techniques to make inferences about underlying neural processes, I also make use of converging methodologies -- combining modern psychophysical approaches with neuroimaging techniques, such as electroencephalography. My behavioural research will utilize psychophysical discrimination tasks to identify the precise aspect of a stimulus observers use in recognizing and discriminating faces. I also will how these behavioural measures correlate with neural activity, including the N170 and N250 (two key markers of face perception within the ERP), but also broader elements of the EEG signal using a range of statistical approaches we have refined to understand brain-behaviour interactions at the level of the individual observer and the individual trial. The results of these studies will provide insight into how the brain processes information about faces and other objects; will determine which aspects of behaviour and neural processing are stable, and which are malleable, based on learning and context; and will enhance our understanding of how sensory information is combined across modalities. Although the research program focuses on fundamental scientific issues, results may provide insights for the development of artificial vision systems, and neurotechnologies to enhance face perception. The research program also will provide excellent training for numerous trainees, equipping them with the scientific knowledge and professional, research, and communication skills to succeed in their future careers as researchers.

视觉系统的主要目标之一是识别物体，以便我们可以适当地与它们互动。虽然对人、地点和事物的识别通常是毫不费力和瞬间的，但感知需要相当长的时间，视觉系统必须克服巨大的障碍才能进行识别。例如，到达我们眼睛的原始图像的各种元素必须得到适当的组织，这样我们才能感知到连贯的、有意义的、完整的对象，而不是不适当地分割、令人困惑的场景。考虑到识别过程的复杂性，我们对识别背后的神经机制了解相对较少也就不足为奇了。目前提案的目标是促进这种理解，特别是关于刺激的作用和关于面部视觉感知的背景信息。在过去的十年里，我的实验室已经改进了许多心理物理和电生理技术，使我们能够在不同于以前可能的水平上解决这些问题。目前的建议扩展了这项工作，特别是关于理解面部识别的神经机制，并分支到新的领域，研究视觉感知的各个方面是如何被上下文线索和经验改变的。虽然我的工作依赖于行为技术来推断潜在的神经过程，但我也利用了融合的方法--将现代心理物理方法与神经成像技术相结合，如脑电图学。我的行为研究将利用心理物理辨别任务来识别观察者在识别和辨别面孔时使用的刺激的准确方面。我还将介绍这些行为测量与神经活动的相关性，包括N170和N250(ERP中面部感知的两个关键标记)，以及使用我们改进的一系列统计方法来理解个体观察者和个体试验水平上的大脑行为交互作用的脑电信号的更广泛元素。这些研究的结果将提供对大脑如何处理关于面部和其他物体的信息的洞察；将根据学习和背景确定行为和神经处理的哪些方面是稳定的，以及哪些方面是可塑性的；并将加强我们对感觉信息如何跨模式组合的理解。尽管该研究计划主要关注基本的科学问题，但研究结果可能会为人工视觉系统和增强面部感知的神经技术的发展提供见解。该研究计划还将为众多受训人员提供出色的培训，使他们掌握科学知识以及专业、研究和沟通技能，以便在未来的研究人员职业生涯中取得成功。