Motion detection on flashed, stationary pedestal gratings: evidence for an opponent-motion mechanism.
Motion detection on flashed, stationary pedestal gratings: evidence for an opponent-motion mechanism.
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闪烁的固定基座光栅上的运动检测：对手运动机制的证据。
DOI：
10.1016/s0042-6989(97)00225-3
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发表时间：
1998
期刊：
影响因子：
1.8
通讯作者：
Kronauer,RE
中科院分区：
文献类型：
--
作者：
Zemany,L;Stromeyer3rd,CF;Chaparro,A;Kronauer,RE
测量对比度阈值以区分持续一个运动周期的垂直 1 c/deg 亮度光栅的左运动和右运动。该测试在两倍阈值的 1 c/deg 固定光栅（基座）上进行，在测试运动期间闪烁。卢和斯珀林[(1995)。 Vision Research, 35, 2697–2722] 认为视觉系统检测测试的潜在的一阶运动，并且不受固定基座的存在（以及它引起的“特征摆动”）的影响。相反，我们观察到固定基座对 7 和 15 Hz 的运动检测有很大影响，而在 0.9-3.7 Hz 则影响较小，固定基座和移动测试之间的空间相位依赖性证明了这一点。在 15 Hz 时，运动阈值下降多达五倍，固定基座处于最佳空间相位（即，基座和测试在运动中间空间同相），并且测试运动的感知方向与基座相反，处于相反相位。还使用移动测试中提供的非常简短（约 1 毫秒）的静态基座来探索相位依赖性。 Lu 和 Sperling 的基座（在测试期间闪烁）具有广泛的左右移动组件，与移动测试相互作用。基座效应可以通过视觉系统对左右移动组件的对比度差异的敏感度比单独对任一组件的敏感度高得多来解释。
Contrast thresholds were measured for discriminating left vs right motion of a vertical, 1 c/deg luminance grating lasting for one cycle of motion. This test was presented on a 1 c/deg stationary grating (pedestal) of twice-threshold, flashed for the duration of the test motion. Lu and Sperling [(1995). Vision Research, 35, 2697–2722] argue that the visual system detects the underlying, first-order motion of the test and is immune to the presence of the stationary pedestal (and the ‘feature wobble’ which it induces). On the contrary, we observe that the stationary pedestal has large effects on motion detection at 7 and 15 Hz, and smaller effects at 0.9–3.7 Hz, evidenced by a spatial phase dependency between the stationary pedestal and moving test. At 15 Hz the motion threshold drops as much as five-fold, with the stationary pedestal in the optimal spatial phase (i.e., pedestal and test spatially in phase at middle of motion), and the perceived direction of the test motion reverses with the pedestal in the opposite phase. Phase dependency was also explored using a very brief (∼ 1 msec) static pedestal presented with the moving test. The pedestal of Lu and Sperling (flashed for the duration of the test) has a broad spectrum of left and right moving components which interact with the moving test. The pedestal effects can be explained by the visual system's much higher sensitivity to the difference of the contrast of right vs left moving components than to either component alone.