空间相互作用揭示了人类弱视中的抑制性皮质网络。

Spatial interactions reveal inhibitory cortical networks in human amblyopia.

作者信息

Wong Erwin H, Levi Dennis M, McGraw Paul V

机构信息

School of Optometry, University of California, Berkeley, CA 94720, USA.

出版信息

Vision Res. 2005 Oct;45(21):2810-9. doi: 10.1016/j.visres.2005.06.008.

DOI:10.1016/j.visres.2005.06.008

PMID:16040080

Abstract

Humans with amblyopia have a well-documented loss of sensitivity for first-order, or luminance defined, visual information. Recent studies show that they also display a specific loss of sensitivity for second-order, or contrast defined, visual information; a type of image structure encoded by neurons found predominantly in visual area A18/V2. In the present study, we investigate whether amblyopia disrupts the normal architecture of spatial interactions in V2 by determining the contrast detection threshold of a second-order target in the presence of second-order flanking stimuli. Adjacent flanks facilitated second-order detectability in normal observers. However, in marked contrast, they suppressed detection in each eye of the majority of amblyopic observers. Furthermore, strabismic observers with no loss of visual acuity show a similar pattern of detection suppression. We speculate that amblyopia results in predominantly inhibitory cortical interactions between second-order neurons.

摘要

患有弱视的人对一级视觉信息（即由亮度定义的视觉信息）的敏感度下降已得到充分证明。最近的研究表明，他们对二级视觉信息（即由对比度定义的视觉信息）也表现出特定的敏感度丧失；二级视觉信息是一种主要由视觉区域A18/V2中的神经元编码的图像结构。在本研究中，我们通过确定在存在二级侧翼刺激的情况下二级目标的对比度检测阈值，来研究弱视是否会破坏V2中空间相互作用的正常结构。相邻的侧翼促进了正常观察者对二级信息的可检测性。然而，与之形成鲜明对比的是，它们抑制了大多数弱视观察者每只眼睛的检测。此外，视力未丧失的斜视观察者也表现出类似的检测抑制模式。我们推测，弱视主要导致二级神经元之间抑制性的皮质相互作用。