Cross- and Iso-oriented surrounds modulate the contrast response function: The effect of surround contrast
Cross- and Iso-oriented surrounds modulate the contrast response function: The effect of surround contrast
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DOI：
10.1167/3.8.1
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发表时间：
2003-01-01
影响因子：
1.8
通讯作者：
Levi, DM
中科院分区：
文献类型：
--
作者：
Yu, C;Klein, SA;Levi, DM
视觉目标的可检测性和外观可以通过周围刺激来调制。在这项研究中，我们问如何交叉和iso-oriented周围调制对比度检测和中央凹视觉的歧视。我们系统地测量了在宽范围的基座和环绕对比度下的色度对比度（TvC）函数。我们的研究结果表明，交叉取向的环绕降低对比度阈值在整个范围内的基座和环绕对比度，但等环绕调制的TvC功能是依赖于相对对比度，是促进时，环绕/基座对比度比C-sur/C-ped < 1和抑制时，C-sur/C-ped > 1。数据拟合表明，交叉环绕调制（促进）主要是由于增益的改善，除了在非常低和高的环绕对比度。另一方面，等环绕调制更复杂，可能反映了由相对对比度确定的不止一个环绕过程。
The detectability and appearance of visual targets can be modulated by surround stimuli. In this study we asked how cross- and iso-oriented surrounds modulate contrast detection and discrimination in foveal vision. We systematically measured the Threshold-versus-Contrast (TvC) functions over a wide range of pedestal and surround contrasts. Our results show that cross-oriented surrounds lower the contrast threshold over the entire range of pedestal and surround contrasts, but iso-surround modulation of the TvC function is dependant on the relative contrast, being facilitative when the surround/pedestal contrast ratio C-sur/C-ped < 1 and suppressive when C-sur/C-ped > 1. Data fitting indicates that cross-surround modulation (facilitation) is mainly due to improved gain, except at very low and high surround contrasts. Iso-surround modulation on the other hand is more complicated, probably reflecting more than one surround process as determined by the relative contrast.