Thibaut Miguel, Tran Thi Ha Chau, Szaffarczyk Sebastien, Boucart Muriel
Laboratoire Neurosciences et Pathologies Fonctionnelles, Université Lille Nord de France, CNRS, France.
Laboratoire Neurosciences et Pathologies Fonctionnelles, Université Lille Nord de France, CNRS, France; Service d'Ophtalmologie, Hôpital Saint Vincent de Paul, Lille, France.
Vision Res. 2014 May;98:46-53. doi: 10.1016/j.visres.2014.03.004. Epub 2014 Mar 20.
Studies in normally sighted people suggest that scene recognition is based on global physical properties and can be accomplished by the low resolution of peripheral vision. We examine the contribution of peripheral and central vision in scene gist recognition in patients with central vision loss and age-matched controls. Twenty-one patients with neovascular age related macular degeneration (AMD), with a visual acuity lower than 20/50, and 15 age-matched normally sighted controls participated in a natural/urban scene categorization task. The stimuli were colored photographs of natural scenes presented randomly at one of five spatial locations of a computer screen: centre, top left, top right, bottom left and bottom right at 12° eccentricity. Sensitivity (d') and response times were recorded. Normally sighted people exhibited higher sensitivity and shorter response times when the scene was presented centrally than for peripheral pictures. Sensitivity was lower and response times were longer for people with AMD than for controls at all spatial location. In contrast to controls patients were not better for central than for peripheral pictures. The results of normally sighted controls indicate that scene categorization can be accomplished by the low resolution of peripheral vision but central vision remains more efficient than peripheral vision for scene gist recognition. People with central vision loss likely categorized scenes on the basis of low frequency information both in normal peripheral vision and in low acuity central vision.
对视力正常者的研究表明，场景识别基于全局物理属性，可通过周边视觉的低分辨率来完成。我们研究了周边视觉和中央视觉在中央视力丧失患者及年龄匹配的对照组的场景主旨识别中的作用。21名患有新生血管性年龄相关性黄斑变性（AMD）、视力低于20/50的患者以及15名年龄匹配的视力正常的对照组参与了一项自然/城市场景分类任务。刺激物是自然场景的彩色照片，随机呈现在电脑屏幕的五个空间位置之一：中心、左上角、右上角、左下角和右下角，偏心度为12°。记录了敏感度（d'）和反应时间。视力正常者在场景呈现在中央时比呈现在周边时表现出更高的敏感度和更短的反应时间。在所有空间位置，AMD患者的敏感度低于对照组，反应时间长于对照组。与对照组不同，患者对中央呈现的图片并不比对周边呈现的图片表现更好。视力正常的对照组的结果表明，场景分类可通过周边视觉的低分辨率来完成，但对于场景主旨识别，中央视觉仍然比周边视觉更有效。中央视力丧失的人可能基于正常周边视觉和低视力中央视觉中的低频信息对场景进行分类。
