Time to wave good-bye to phase scrambling: creating controlled scrambled images using diffeomorphic transformations.
Time to wave good-bye to phase scrambling: creating controlled scrambled images using diffeomorphic transformations.
复制标题
是时候告别相位扰乱了：使用微分同胚变换创建受控的扰乱图像。
作者：
Bobby Stojanoski;R. Cusack
为了将与识别物体相关的神经机制与处理基本视觉特性的神经机制隔离开来，需要包含与物体相同的感知特性但不可识别的控制刺激。我们证明，传统的方法产生控制刺激（相位置乱，框置乱，纹理置乱）产生差的控制，因为他们显着扭曲的基本视觉属性（例如，空间频率、知觉组织），甚至视觉处理的最早阶段也对其敏感。我们开发了一种新的置乱方法，使用一种保留图像的基本感知特性，同时去除意义的非对称变换。我们获得了感知评级，以确定删除识别所需的最小扰频量。我们假设，我们的“随机”图像将在视觉系统的最早阶段产生神经活动，与其他加扰方法相比，这种活动与完整图像的反应更接近。为了验证这一假设，我们使用了HMAX物体识别计算模型，并将视觉系统最早阶段（S1，C1和S2层）的模拟神经活动在一组149张图像之间进行了比较，这些图像使用每种失真方法进行了加密。我们发现，在模型的每一层中，杂乱的“变形”图像与完整的图像是无法区分的，但是所有其他的失真方法产生了完全不同的模式。我们的研究结果表明，“类形”的图像作为更合适的控制刺激，在神经影像学研究，旨在解开知觉和语义对象属性的表征。
To isolate the neural mechanisms associated with recognizing objects from those processing basic visual properties, control stimuli are required that contain the same perceptual properties as the objects but are unrecognizable. We demonstrate that conventional methods for generating control stimuli (phase scrambling, box scrambling, texture scrambling) yield poor controls because they dramatically distort the basic visual properties (e.g., spatial frequency, perceptual organization) to which even the earliest stages of visual processing are sensitive. We developed a new scrambling method, using a diffeomorphic transformation that preserves the basic perceptual properties of the image while removing meaning. We acquired perceptual ratings to determine the least amount of scrambling necessary to remove recognition. We hypothesized that our "diffeomorphic" images would produce neural activity at the earliest stages of the visual system that more closely matched activity in response to intact images relative to the other scrambling methods. To test this hypothesis, we used the HMAX computational model of object recognition and compared the simulated neural activity at the earliest stages of the visual system (layers S1, C1, and S2) between a set of 149 images scrambled using each distortion method to their intact version. We found that scrambled "diffeomorphed" images were indistinguishable to intact images in each layer of the model, but all of the other distortion methods yielded quite different patterns. Our results indicate that "diffeomorphed" images serve as more appropriate control stimuli in neuroimaging studies that aim to disentangle the representations of perceptual and semantic object properties.
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影响因子：
3.7
作者：
Felleman, Daniel J.;Van Essen, David C.
通讯作者：
Van Essen, David C.
DOI：
10.1073/pnas.92.18.8135
发表时间：
1995-08-29
影响因子：
11.1
作者：
MALACH, R;REPPAS, JB;TOOTELL, RBH
通讯作者：
TOOTELL, RBH
影响因子：
1.8
作者：
Rosenholtz R;Huang J;Raj A;Balas BJ;Ilie L
通讯作者：
Ilie L
影响因子：
1.8
作者：
Wright JM;Morris AP;Krekelberg B
通讯作者：
Krekelberg B
影响因子：
1.8
作者：
Ales, Justin M.;Farzin, Faraz;Norcia, Anthony M.
通讯作者：
Norcia, Anthony M.