School of Philosophy, Psychology and Language Sciences, University of Edinburgh, Edinburgh, United Kingdom.
PLoS One. 2021 Nov 4;16(11):e0254195. doi: 10.1371/journal.pone.0254195. eCollection 2021.
The blind spot is a region in the temporal monocular visual field in humans, which corresponds to a physiological scotoma within the nasal hemi-retina. This region has no photoreceptors, so is insensitive to visual stimulation. There is no corresponding perceptual scotoma because the visual stimulation is "filled-in" by the visual system. Investigations of visual perception in and around the blind spot allow us to investigate this filling-in process. However, because the location and size of the blind spot are individually variable, experimenters must first map the blind spot in every observer. We present an open-source tool, which runs in Psychopy software, to estimate the location and size of the blind spot psychophysically. The tool will ideally be used with an Eyelink eye-tracker (SR Research), but it can also run in standalone mode. Here, we explain the rationale for the tool and demonstrate its validity in normally-sighted observers. We develop a detailed map of the blind spot in one observer. Then, in a group of 12 observers, we propose a more efficient, pragmatic method to define a "safe zone" within the blind spot, for which the experimenter can be fully confident that visual stimuli will not be seen. Links are provided to this open-source tool and a user manual.
盲点是人类颞侧单眼视野中的一个区域，对应于鼻侧半视网膜内的生理盲点。该区域没有光感受器，因此对视觉刺激不敏感。由于视觉系统“填补”了视觉刺激，因此没有相应的感知盲点。对盲点及其周围的视觉感知的研究可以帮助我们研究这个填补过程。然而，由于盲点的位置和大小因人而异，实验者必须首先在每个观察者中绘制盲点图。我们提出了一种开源工具，该工具在 Psychopy 软件中运行，用于通过心理物理学方法来估计盲点的位置和大小。该工具理想情况下与 Eyelink 眼动追踪器（SR Research）一起使用，但也可以在独立模式下运行。在这里，我们解释了该工具的基本原理，并在正常视力的观察者中证明了其有效性。我们在一个观察者中开发了一个详细的盲点图。然后，在 12 名观察者组成的小组中，我们提出了一种更有效、更实用的方法来定义盲点内的“安全区”，实验者可以完全确信视觉刺激不会被看到。提供了该开源工具和用户手册的链接。
