Hübner R
Institut für Psychologie, Technische Universität Braunschweig, Germany.
Vision Res. 1996 Nov;36(21):3429-39. doi: 10.1016/0042-6989(96)00088-0.
If the spatial-frequency of sinusoidal signals in a contrast-detection experiment varies randomly from trial to trial, then performance is decreased compared with that in a situation where it remains constant. This spatial-frequency uncertainty effect can more or less be compensated by presenting informative cues shortly before each trial. Single-band, as well as multiple-band models, have been proposed to explain the uncertainty and cuing effects. While the latter assume that under uncertainty multiple channels are monitored simultaneously, the former propose that in each trial a single, but sometimes inappropriate, channel is selected for monitoring. Until now it is open which of these models is valid. Therefore, psychometric functions were collected under different conditions of spatial-frequency uncertainty. It appears that the size of the uncertainty effect varies with spatial-frequency. This result can be explained by a multiple-band model, as computational analysis reveals.
在对比度检测实验中，如果正弦信号的空间频率在每次试验中随机变化，那么与空间频率保持恒定的情况相比，性能会下降。通过在每次试验前不久呈现信息性线索，这种空间频率不确定性效应或多或少可以得到补偿。已经提出了单波段以及多波段模型来解释不确定性和线索效应。后者假设在不确定性情况下多个通道同时被监测，而前者提出在每次试验中选择一个单一但有时不合适的通道进行监测。到目前为止，这些模型中哪一个是有效的还不确定。因此，在不同的空间频率不确定性条件下收集了心理测量函数。如计算分析所示，不确定性效应的大小似乎随空间频率而变化。这一结果可以用多波段模型来解释。
