Tong Jianliang, Aydin Murat, Bedell Harold E
University of Houston, Houston, Texas 77204-2020, USA.
Percept Psychophys. 2007 Jan;69(1):48-55. doi: 10.3758/bf03194452.
Recent evidence indicates that motion smear can provide useful information for the detection and discrimination of motion. Further, it has been shown that the perception of motion smear depends critically on the density of dots in a random-dot (RD) stimulus. Therefore, in the present experiments, the contribution of perceived motion smear to direction-of-motion discrimination was evaluated using RD targets of different densities. Thresholds for direction-of-motion discrimination and the extent of perceived motion smear were determined for RD stimuli with densities of 1, 2, and 10 dots/deg(2), presented for 200 msec at a velocity of 4, 8, or 12 deg/sec. To evaluate the contribution of information about orientation from motion smear, thresholds for orientation discrimination were measured using parallel lines with the same length as the extent of perceived smear. Despite the opportunity for increased summation as RD density increases, our results indicate that direction-of-motion discrimination worsens. Because perception of motion smear is reduced with an increase in RD density, our results are consistent with a facilitation of direction-of-motion discrimination by visible motion smear.
最近的证据表明，运动模糊可为运动的检测和辨别提供有用信息。此外，研究表明，对运动模糊的感知严重依赖于随机点（RD）刺激中的点密度。因此，在本实验中，使用不同密度的RD目标评估了感知到的运动模糊对运动方向辨别的贡献。对于密度为1、2和10个点/度²的RD刺激，以4、8或12度/秒的速度呈现200毫秒，确定了运动方向辨别阈值和感知到的运动模糊程度。为了评估来自运动模糊的方向信息的贡献，使用与感知到的模糊程度相同长度的平行线测量了方向辨别阈值。尽管随着RD密度增加有更多求和的机会，但我们的结果表明运动方向辨别变差。由于随着RD密度增加对运动模糊的感知降低，我们的结果与可见运动模糊促进运动方向辨别一致。
