Development and experimental evaluation of psychophysical models of uncertainty and multidimensionality

本研究旨在建立包含刺激不确定性和多维感觉尺度的心理物理模型，并在心理物理实验中考察刺激不确定性和多维度的影响。在模型开发中，将刺激不确定性和多维性纳入thurston模型。我们将感觉强度的方差表示为刺激不确定性的函数，并在多维空间中建立了感觉分布和判断标准的模型。由于技术上的困难，模型还没有完成。在实验中，我们控制了目标音调的频率和空间位置的不确定性，并研究了两个维度在强度分辨率上的相互作用。结果表明，任何一个维度的不确定性都会降低强度分辨率，而频率信号的影响取决于位置的不确定性（Futakuchi等人，in press; Futakuchi & Mori, submitted; Mori & Futakuchi, 1999）。在视觉搜索实验中，我们还研究了空间位置和亮度对方向敏感性的相互作用。结果表明，方向灵敏度取决于位置不确定性、亮度和背景对比度（Mori, Kataoka, & Kusano，提交；Ohtani & Mori，提交）。

The purpose of this research project was to develop psychophysical models incorporating stimulus uncertainty and multi-dimensional sensory scales, and to examine the effects of stimulus uncertainty and multi-dimensionality in psychophysical experiments.In the model development, stimulus uncertainty and multi-dimensionality was incorporated into a Thurstonian model. We expressed variance of sensory magnitude as a function of stimulus uncertainty, and modeled sensory distributions and judgment criteria in multidimensional space. Due to technical difficulties, the model has not been completed yet.In the experiments, we manipulated uncertainty in frequency and spatial location of target tones, and examined the interaction between the two dimensions on intensity resolution. The results showed that uncertainty in either dimension lowered intensity resolution, and that the effects of frequency cueing depended on location uncertainty (Futakuchi et al., in press ; Futakuchi ＆ Mori, submitted ; Mori ＆ Futakuchi, 1999).We also examined the interaction of spatial location and luminance on orientation sensitivity in visual search experiments. The results showed that orientation sensitivity depended on location uncertainty, luminance, and contrast against the background (Mori, Kataoka, ＆ Kusano, submitted ; Ohtani ＆ Mori, submitted).