BOLD Activation Varies Parametrically with Corner Angle Throughout Human Retinotopic Cortex
BOLD Activation Varies Parametrically with Corner Angle Throughout Human Retinotopic Cortex
复制标题
BOLD 激活随整个人类视网膜专题皮层的角角呈参数变化
作者：
Xoana G. Troncoso;P. Tse;S. Macknik;G. Caplovitz;P. Hsieh;Alexander A. Schlegel;J. Otero;S. Martinez
交替亮度星星（ABS）是一种错觉，它提供了对亮度感知和拐角角度之间关系的洞察。最近的心理物理学研究表明，这种错觉的角落的显着性与角落的角度参数变化，与尖锐的角度导致强烈的错觉感知和浅的角度导致弱感知。据推测，错觉的效果出现，因为表面的角落和视觉感受野的形状之间的相互作用：尖锐的表面角落可能会创建高的局部对比度的热点，由于中央环绕和其他早期的感受野处理。如果这一假设是正确的，那么早期的视觉神经元应该对表面边缘的尖角和弯曲部分有强烈的反应。事实上，早期视觉神经元的主要作用可能是定位表面沿着边缘的不连续性。如果是这样的话，所有早期视觉区域对尖角的BOLD反应都应该比对浅角的BOLD反应大。另一方面，如果角落处理仅限于大脑的某些区域，那么只有这些特定区域才会对尖锐的角落比浅的角落表现出更大的反应。为了解决这个问题，我们探索了BOLD相关的ABS错觉在人类视觉皮层使用功能磁共振成像。我们发现，BOLD信号在整个视觉皮层中随角角度参数变化，提供了ABS错觉的第一个神经生理学相关性。这一发现提供了一个神经生理学的基础上，以前报道的心理物理数据表明，角落的显着性变化的参数与角落的角度。我们认为，所有的早期视觉区域定位不连续沿着边缘的表面，和特定的皮质角落处理电路进一步建立这些不连续的具体性质，如他们的方向。
The Alternating Brightness Star (ABS) is an illusion that provides insight into the relationship between brightness perception and corner angle. Recent psychophysical studies of this illusion have shown that corner salience varies parametrically with corner angle, with sharp angles leading to strong illusory percepts and shallow angles leading to weak percepts. It is hypothesized that the illusory effects arise because of an interaction between surface corners and the shape of visual receptive fields: sharp surface corners may create hotspots of high local contrast due to processing by center–surround and other early receptive fields. If this hypothesis is correct, early visual neurons should respond powerfully to sharp corners and curved portions of surface edges. Indeed, the primary role of early visual neurons may be to localize the discontinuities along the edges of surfaces. If so, all early visual areas should show greater BOLD responses to sharp corners than to shallow corners. On the other hand, if corner processing is exclusively constrained to certain areas of the brain, only those specific areas will show greater responses to sharp vs shallow corners. To address this we explored the BOLD correlates of the ABS illusion in the human visual cortex using fMRI. We found that BOLD signal varies parametrically with corner angle throughout the visual cortex, offering the first neurophysiological correlates of the ABS illusion. This finding provides a neurophysiological basis for the previously reported psychophysical data that showed that corner salience varied parametrically with corner angle. We propose that all early visual areas localize discontinuities along the edges of surfaces, and that specific cortical corner-processing circuits further establish the specific nature of those discontinuities, such as their orientation.
DOI：
10.1073/pnas.98.4.1935
发表时间：
2001-02
影响因子：
11.1
作者：
Mariano Sigman;Guillermo A. Cecchi;Charles D. Gilbert;M. Magnasco
通讯作者：
Mariano Sigman;Guillermo A. Cecchi;Charles D. Gilbert;M. Magnasco
影响因子：
56.9
作者：
SERENO, MI;DALE, AM;TOOTELL, RBH
通讯作者：
TOOTELL, RBH
影响因子：
2.5
作者：
Pasupathy, A;Connor, CE
通讯作者：
Connor, CE