Abstract Well-structured stimuli presentation is essential in eye-tracking research to test predefined hypotheses reliably and to conduct relevant gazing behavior studies. Several bottom-up factors associated with stimuli presentation (such as stimuli orientation, size etc.) can influence gazing behavior. However, only a small number of scientific papers address these factors in a sensory and consumer science context and thus provide guidance to practitioners. The two presented eye-tracking studies on food images aimed at evaluating the effect of the bottom-up factors stimulus size, background of the picture, orientation of food product presentation, the evaluated products and the number of alternatives. Significant effects of product group were found in the case of all eye-movement parameters except time to first fixation and first fixation duration. In contrary, orientation significantly influenced only the time to first fixation and first fixation duration parameters. Stimulus size significantly increased fixation and dwell count, while background showed no significant effects. Furthermore, significant relationships were found between the number of presented images and eye-movement and decision time. Less time was needed in 2AFC (alternative forced choice test), 3AFC and 4AFC and significantly more time was needed to choose one alternative out of 7AFC and 8AFC. The results of the two studies show that the investigated bottom-up factors can significantly influence gazing behavior, and therefore need to be carefully considered when planning or comparing results of eye-tracking experiments.

中文翻译：

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呈现刺激的结构影响凝视行为和选择

摘要 结构良好的刺激呈现在眼动追踪研究中是必不可少的，以可靠地测试预定义的假设并进行相关的凝视行为研究。与刺激呈现相关的几个自下而上的因素（例如刺激方向、大小等）会影响凝视行为。然而，只有少数科学论文在感官和消费者科学的背景下解决这些因素，从而为从业者提供指导。两人展示了对食品图像的眼动追踪研究，旨在评估自下而上因素刺激大小、图片背景、食品展示方向、评估产品和替代品数量的影响。除了首次注视时间和首次注视持续时间外，在所有眼动参数的情况下都发现了产品组的显着影响。相反，方向​​仅显着影响首次注视时间和首次注视持续时间参数。刺激大小显着增加了固定和停留计数，而背景显示没有显着影响。此外，还发现呈现图像的数量与眼球运动和决策时间之间存在显着关系。在 2AFC（替代强制选择测试）、3AFC 和 4AFC 中需要的时间更少，而从 7AFC 和 8AFC 中选择一个替代方案所需的时间明显更多。两项研究的结果表明，调查的自下而上的因素可以显着影响凝视行为，