Bouet Romain, Knoblauch Kenneth
Institut National de la Santé et de la Recherche Médicale, Cerveau et Vision, Bron cedex, France.
Vis Neurosci. 2004 May-Jun;21(3):283-9. doi: 10.1017/s0952523804213141.
We measured the regions of the equiluminant plane that are exploited by observers during a Yes/No detection task. The signal was a 640-ms Gaussian modulation (sigma(t) = 160 ms) of a Gaussian spatial patch (sigma(s) = 2.4 deg) presented in chromatically bivariate uniform noise. One component of the noise was along the direction axial with the signal in color space, the other perpendicular. Four signal directions were tested: along cardinal LM and S axes and two intermediate directions to which the cardinal axes were equally sensitive. The distribution of noise chromaticities from each trial was correlated with the observers' responses and the presence and absence of the signal to build a classification image of the distribution of chromaticities on which the decision of the observer was based. The images show a narrowly selective peak in the signal direction flanked by regions with a broader selectivity. These results raise the possibility that detection judgments are mediated by both linear and nonlinear mechanisms with peak sensitivities between the cardinal directions.
我们测量了观察者在“是/否”检测任务中所利用的等亮度平面区域。信号是一个高斯空间斑块（标准差(s)=2.4度）的640毫秒高斯调制（标准差(t)=160毫秒），呈现于双色均匀噪声中。噪声的一个分量沿颜色空间中与信号轴向的方向，另一个垂直。测试了四个信号方向：沿着基本的LM和S轴以及两个基本轴同等敏感的中间方向。每次试验的噪声色度分布与观察者的反应以及信号的有无相关，以构建观察者决策所基于的色度分布分类图像。图像显示在信号方向上有一个狭窄的选择性峰值，两侧是具有更广泛选择性的区域。这些结果增加了检测判断由基本方向之间具有峰值敏感性的线性和非线性机制介导的可能性。
