Using steady-state visual evoked potentials (SSVEP) to measure brain responses to faces and objects

使用稳态视觉诱发电位 (SSVEP) 测量大脑对面部和物体的反应

• 批准号: RGPIN-2014-05951
• 负责人: Tanaka, James
• 金额: $ 2.48万
• 依托单位: University of Victoria
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2016
• 资助国家: 加拿大
• 起止时间: 2016-01-01 至 2017-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=611940
• 关键词: Using; steady; state; visual; evoked

The proposed research investigates the neural correlates of human face and object perception using steady-state visual-evoked potentials (SSVEP). It has been shown that repetitive stimulation of the human visual system produces oscillations in the electroencephalogram (EEG) that mimics the frequency of the repeating stimulus – the SSVEP (Regan 2009). The proposed experiments will employ an adaptation paradigm in which an adapting face of the same identity (e.g., “Joe”) is repeatedly flashed on the screen at a periodic rate of presentation (4 Hz). Based on a previous study (Rossion & Boremanse, 2011), the continuous presentation of the same face identity produces a reduction in the neural signal (i.e., repetition suppression effect). In the test phase, faces of different identities (e.g., “Fred”, “Bob”, “Bill”, etc.) are shown at the rate of stimulation used for adaptation. The presentation of different faces cause an abrupt increase in the EEG signal indicating that the SSVEP is sensitive to the changing identities of individual faces. The advantages of the SSVEP technique over traditional event-related potentials (ERPs) are that the method yields a high signal-to-noise ratio, requires substantially fewer experimental trials and is a robust measure of perceptual discrimination in high-level vision. However, it is not known if the SSVEP is responsive to the effects of perceptual experience and learning. These questions are addressed in the current proposal by testing real world and laboratory-trained experts. In the first series of experiments, real world bird experts who have extensive experience to birds and mono-racial people who have extensive experience to own-, but not other-race faces will be studied. We hypothesize that bird experts and own-race face experts will exhibit a greater SSVEP to stimuli in the domain of expertise (i.e., birds for bird experts, own-race faces for own-race experts) than novices. Moreover, SSVEP differences will be correlated with differences in recognition of objects and faces from the domain of expertise. Second, we will investigate the acquisition of perceptual expertise in a laboratory training studies. We predict that it is the kind, not the amount of perceptual experience that determines perceptual expertise and modulates the strength of the SSVEP signal. In the final set of experiments, we will examine whether the magnitude of the SSVEP distinguishes individual differences in face recognition and inter-group differences between neurotypical people and a population with known face recognition deficits (i.e., people on the autism spectrum). In summary, the proposed program of research fills a critical gap in our understanding of mechanisms that guide the processes of high-level vision, linking the observer’s perceptual experience and abilities with differences in brain activity.

拟议的研究利用稳态视觉诱发电位（SSVEP）研究人脸和物体感知的神经相关性。研究表明，人类视觉系统的重复刺激会产生模仿重复刺激频率的脑电图 (EEG) 振荡——SSVEP (Regan 2009)。所提出的实验将采用一种适应范式，其中相同身份（例如“Joe”）的适应面孔以周期性呈现速率（4 Hz）在屏幕上重复闪烁。根据之前的一项研究（Rossion & Boremanse，2011），相同面部身份的连续呈现会产生神经信号的减少（即重复抑制效应）。在测试阶段，不同身份的面孔（例如“Fred”、“Bob”、“Bill”等）以用于适应的刺激速率显示。不同面孔的呈现会导致脑电图信号突然增加，表明 SSVEP 对各个面孔的身份变化很敏感。与传统的事件相关电位 (ERP) 相比，SSVEP 技术的优点在于该方法可产生高信噪比，需要的实验次数要少得多，并且是高级视觉知觉辨别的稳健测量方法。 然而，尚不清楚 SSVEP 是否对感知体验和学习的影响做出反应。目前的提案通过测试现实世界和经过实验室培训的专家来解决这些问题。在第一个系列的实验中，将研究对鸟类拥有丰富经验的现实世界鸟类专家和对拥有但不拥有其他种族面孔拥有丰富经验的单一种族人士。我们假设鸟类专家和同场比赛面孔专家将比新手对专业领域的刺激表现出更大的 SSVEP（即鸟类对鸟类专家，同场比赛面孔对同场专家）。此外，SSVEP 差异将与专业领域中物体和面孔识别的差异相关。其次，我们将调查实验室培训研究中感知专业知识的获取。我们预测，决定感知专业知识并调节 SSVEP 信号强度的是感知体验的种类，而不是感知体验的数量。在最后一组实验中，我们将检查 SSVEP 的大小是否能够区分神经正常人群和已知面部识别缺陷人群（即自闭症谱系人群）之间面部识别的个体差异以及群体间差异。总之，拟议的研究计划填补了我们对指导高级视觉过程的机制的理解中的一个关键空白，将观察者的感知体验和能力与大脑活动的差异联系起来。