Chen Yi-Chuan, Huang Pi-Chun, Yeh Su-Ling, Spence Charles
Department of Experimental Psychology, University of Oxford, Oxford, OX1 3UD, UK.
Seeing Perceiving. 2011;24(6):623-38. doi: 10.1163/187847611X603765.
We examined the crossmodal effect of the presentation of a simultaneous sound on visual detection and discrimination sensitivity using the equivalent noise paradigm (Dosher and Lu, 1998). In each trial, a tilted Gabor patch was presented in either the first or second of two intervals embedded in dynamic 2D white noise with one of seven possible contrast levels. The results revealed that the sensitivity of participants' visual detection and discrimination performance were both enhanced by the presentation of a simultaneous sound, though only close to the noise level at which participants' target contrast thresholds started to increase with the increasing noise contrast. A further analysis of the psychometric function at this noise level revealed that the increase in sensitivity could not be explained by the reduction of participants' uncertainty regarding the onset time of the visual target. We suggest that this crossmodal facilitatory effect may be accounted for by perceptual enhancement elicited by a simultaneously-presented sound, and that the crossmodal facilitation was easier to observe when the visual system encountered a level of noise that happened to be close to the level of internal noise embedded within the system.
我们使用等效噪声范式（多舍尔和卢，1998年）研究了同时呈现声音对视觉检测和辨别敏感性的跨模态效应。在每次试验中，一个倾斜的加博尔斑块会出现在嵌入动态二维白噪声的两个时间间隔中的第一个或第二个间隔内，白噪声有七种可能的对比度水平之一。结果显示，同时呈现声音会提高参与者的视觉检测和辨别性能的敏感性，不过这仅在接近参与者的目标对比度阈值开始随着噪声对比度增加而提高的噪声水平时才会出现。对该噪声水平下的心理测量函数的进一步分析表明，敏感性的提高无法通过参与者对视觉目标出现时间的不确定性降低来解释。我们认为，这种跨模态促进效应可能是由同时呈现的声音引发的感知增强所导致的，并且当视觉系统遇到的噪声水平恰好接近系统内部嵌入的噪声水平时，跨模态促进作用更容易观察到。
