Graduate Institute of Biomedical Sciences, China Medical University, No. 91, Xue-Shi Road, Taichung, 40402, Taiwan.
Sci Rep. 2022 Nov 10;12(1):19231. doi: 10.1038/s41598-022-23139-3.
Visual search is to find targets while ignoring distractors. Previous studies established that a target is more difficult to identify if aligned collinearly with other items, called the collinear search impairment. Since older adults have lower perceptual grouping ability than younger adults, benefits in visual search may occur for older adults for they may be less distracted by the collinear distractors. Three experiments were carried out to compare 45 younger and 45 older healthy adults. Participants were asked to identify a local target either in the column with items collinearly aligned to each other (the overlapping condition) or in the background (the non-overlapping condition), and the response difference between the two conditions is the collinear search impairment. Results showed that both groups showed reliable search impairment specific to collinear distractor regardless of grouping difficulty and task demands, and the impairment strength increased with the grouping strength of the collinear distractor. Further analysis revealed that the response times of older adults increased in a multiplicative manner to that of younger adults, suggesting that longer response of older adults spread to multiple underlying processing including grouping and suppression of collinear distractors. Together, the results suggest that older adults were still distracted in visual search even when grouping was required on a distractor. Our findings also highlight how general slowing may delay suppression processing in visual search.
视觉搜索是指在忽略干扰物的情况下找到目标。先前的研究表明，如果目标与其他项目呈直线对齐，那么目标就更难被识别，这被称为直线搜索障碍。由于老年人的知觉分组能力比年轻人差，因此他们在视觉搜索中可能会获得更多的益处，因为他们可能不会被直线干扰物分散注意力。进行了三项实验，比较了 45 名年轻健康成年人和 45 名年长健康成年人。要求参与者识别一列中彼此直线对齐的项目（重叠条件）或背景中的本地目标（非重叠条件），这两种条件之间的反应差异即为直线搜索障碍。结果表明，两组人都表现出了对直线干扰物的可靠搜索障碍，无论分组难度和任务要求如何，并且这种障碍强度随着直线干扰物的分组强度的增加而增加。进一步的分析表明，老年人的反应时间呈乘法增加，与年轻人的反应时间相比，这表明老年人的反应时间延长会扩展到包括分组和抑制直线干扰物在内的多个潜在处理过程。总之，这些结果表明，即使在需要对干扰物进行分组的情况下，老年人在视觉搜索中仍然会受到干扰。我们的发现还强调了一般的减速如何会延迟视觉搜索中的抑制处理。
