Brunt Diamond, Legge Gordon E, Fletcher Donald C, Xiong Yingzi
School of Medicine, University of Kansas, Kansas City, Kansas, United States.
Envision Research Institute, Wichita, Kansas, United States.
Invest Ophthalmol Vis Sci. 2025 Jul 1;66(9):38. doi: 10.1167/iovs.66.9.38.
The perception of straight ahead (PSA) is an important reference for spatial orientation. Although individuals with low vision often report difficulties in spatial tasks, it is not clear whether they face challenges in defining PSA. We asked whether low vision leads to increased biases and variabilities in visual PSA, and whether these changes, if any, would generalize to auditory PSA, due to the dominant role of vision in spatial tasks.
Thirty-five low-vision participants and 17 age-matched control participants completed visual and auditory PSA tasks in which they adjusted the location of a brief LED light or a finger snap sound from a speaker to appear to be straight ahead. To control for proprioception, participants also completed a PSA task in which they pointed to their straight ahead while blindfolded.
The magnitudes of biases and variabilities in visual PSA were significantly associated with binocular acuity and contrast sensitivity, but the laterality of the visual biases was not associated with interocular asymmetries in acuity, contrast sensitivity, or lateral asymmetries in the binocular visual field. Low-vision individuals showed larger magnitudes of biases and variabilities in the auditory PSA independent of age or hearing status, possibly indicating a cross-modal impact of vision loss on sound localization. Despite the changes in visual and auditory PSA, the low-vision participants showed intact proprioception PSA.
The changes in visual and auditory PSA may contribute to spatial orientation challenges encountered by low-vision individuals, and the robust proprioceptive PSA may play an important compensatory role.
对正前方的感知（PSA）是空间定向的重要参考。尽管视力低下的个体经常报告在空间任务中存在困难，但尚不清楚他们在定义PSA时是否面临挑战。我们研究了视力低下是否会导致视觉PSA的偏差和变异性增加，以及这些变化（如果有的话）是否会由于视觉在空间任务中的主导作用而推广到听觉PSA。
35名视力低下参与者和17名年龄匹配的对照参与者完成了视觉和听觉PSA任务，他们调整来自扬声器的短暂LED光或弹指声的位置，使其看起来在正前方。为了控制本体感觉，参与者还完成了一项PSA任务，即他们在蒙眼时指向自己的正前方。
视觉PSA的偏差和变异性大小与双眼视力和对比敏感度显著相关，但视觉偏差的偏向性与视力、对比敏感度的眼间不对称或双眼视野的侧向不对称无关。视力低下个体在听觉PSA中表现出更大的偏差和变异性，与年龄或听力状况无关，这可能表明视力丧失对声音定位有跨模态影响。尽管视觉和听觉PSA发生了变化，但视力低下参与者的本体感觉PSA完好无损。
视觉和听觉PSA的变化可能导致视力低下个体遇到的空间定向挑战，而强大的本体感觉PSA可能发挥重要的补偿作用。
