Evans David W, Wang Yizhong, Haggerty Kevin M, Thibos Larry N
School of Optometry, Indiana University, Bloomington, IN 47405, United States.
Vision Res. 2010 Jan;50(1):20-30. doi: 10.1016/j.visres.2009.10.001.
The effect of sampling irregularity and window size on orientation discrimination was investigated using discretely sampled gratings as stimuli. For regular sampling arrays, visual performance could be accounted for by a theoretical analysis of aliasing produced by undersampling. For irregular arrays produced by adding noise to the location of individual samples, the incidence of perceived orientation reversal declined and the spatial frequency range of flawless performance expanded well beyond the nominal Nyquist frequency. These results provide a psychophysical method to estimate the spatial density and the degree of irregularity in the neural sampling arrays that limit human visual resolution.
使用离散采样光栅作为刺激物,研究了采样不规则性和窗口大小对方向辨别能力的影响。对于规则采样阵列,视觉表现可以通过对欠采样产生的混叠进行理论分析来解释。对于通过向单个样本位置添加噪声而产生的不规则阵列,感知到的方向反转发生率下降,完美表现的空间频率范围扩展到远超过标称奈奎斯特频率。这些结果提供了一种心理物理学方法,以估计限制人类视觉分辨率的神经采样阵列中的空间密度和不规则程度。