Gottlieb M D, Kietzman M L
Percept Mot Skills. 1987 Apr;64(2):343-54. doi: 10.2466/pms.1987.64.2.343.
The temporal integration of luminous energy was compared in the fovea and at 7 degrees eccentricity using two-pulse stimuli and two methodologies. The two-pulse stimuli consisted of two 1-msec. light pulses separated by intervals of darkness ranging from 1 to 400 msec.; they were provided by a glow modulator tube transilluminating a 21.8' opal glass target. In Exp. 1 (equal-performance design), integration functions were generated using a forced-choice staircase procedure to estimate threshold luminance. The data for two Os showed that the critical duration (CD), and thus the period of complete integration, was briefer in the fovea than at 7 degrees. Beyond the CD, integration continued to differ for the two retinal locations. In the fovea, two-pulse stimuli beyond CD evidenced partial integration and at the longest stimulus durations no integration or inhibition. In contrast, at 7 degrees stimuli beyond CD appeared to evidence probability summation. In Exp. 2 (equal-energy design), integration functions were generated by measuring the detectability of two-pulse stimuli of different durations but equal in total luminous energy. A signal-detection procedure yielded measures of both response frequency and signal detectability, P(A). The data for two Os showed that for both measures CD was briefer in the fovea than at 7 degrees. Also, in the fovea, long two-pulse stimuli appeared to show no integration or inhibition. Both experiments then showed a foveal-peripheral difference in two-pulse measures of visual temporal integration, with the fovea evidencing less integration. In addition, the forced-choice and signal-detection procedures showed that these loci differences in integration were independent of the Os' response criterion.
使用双脉冲刺激和两种方法，比较了中央凹和7度偏心率处的光能时间整合。双脉冲刺激由两个1毫秒的光脉冲组成，其间有1至400毫秒的黑暗间隔；它们由一个辉光调制管提供，该调制管照亮一个21.8'的乳白玻璃靶标。在实验1（等性能设计）中，使用强制选择阶梯程序生成整合函数，以估计阈值亮度。两名受试者的数据表明，中央凹的临界持续时间（CD），即完全整合的时期，比7度处更短。超过CD后，两个视网膜位置的整合仍存在差异。在中央凹，超过CD的双脉冲刺激显示出部分整合，在最长刺激持续时间时没有整合或抑制。相比之下，在7度处，超过CD的刺激似乎显示出概率总和。在实验2（等能量设计）中，通过测量不同持续时间但总光能相等的双脉冲刺激的可检测性来生成整合函数。信号检测程序产生了反应频率和信号可检测性P(A)的测量值。两名受试者的数据表明，对于这两种测量，中央凹的CD都比7度处更短。此外，在中央凹，长双脉冲刺激似乎没有显示出整合或抑制。两个实验都显示了视觉时间整合双脉冲测量中的中央凹-周边差异，中央凹的整合较少。此外，强制选择和信号检测程序表明，这些整合位点的差异与受试者的反应标准无关。
