Norris Jade Eloise, Clayton Sarah, Gilmore Camilla, Inglis Matthew, Castronovo Julie
1 Department of Psychology, University of Bath, Bath, UK.
2 Department of Health Sciences, University of Leicester, Leicester, UK.
Q J Exp Psychol (Hove). 2019 May;72(5):1037-1046. doi: 10.1177/1747021818779020. Epub 2018 Jun 4.
Recent studies have highlighted the influence of visual cues such as dot size and cumulative surface area on the measurement of the approximate number system (ANS). Previous studies assessing ANS acuity in ageing have all applied stimuli generated by the Panamath protocol, which does not control nor measure the influence of convex hull. Crucially, convex hull has recently been identified as an influential visual cue present in dot arrays, with its impact on older adults' ANS acuity yet to be investigated. The current study therefore investigated the manipulation of convex hull by the Panamath protocol, and its effect on the measurement of ANS acuity in younger and older participants. First, analyses of the stimuli generated by Panamath revealed a confound between numerosity ratio and convex hull ratio. Second, although older adults were somewhat less accurate than younger adults on convex hull incongruent trials, ANS acuity was broadly similar between the groups. These findings have implications for the valid measurement of ANS acuity across all ages, and suggest that the Panamath protocol produces stimuli that do not adequately control for the influence of convex hull on numerosity discrimination.
最近的研究强调了诸如点大小和累积表面积等视觉线索对近似数系统（ANS）测量的影响。以往评估衰老过程中ANS敏锐度的研究均采用了由Panamath协议生成的刺激，该协议既不控制也不测量凸包的影响。至关重要的是，凸包最近已被确认为点阵列中存在的一种有影响力的视觉线索，其对老年人ANS敏锐度的影响尚待研究。因此，本研究调查了Panamath协议对凸包的操控及其对年轻和年长参与者ANS敏锐度测量的影响。首先，对Panamath生成的刺激进行分析发现，数量比与凸包比之间存在混淆。其次，尽管在凸包不一致的试验中，老年人的准确性略低于年轻人，但两组之间的ANS敏锐度大致相似。这些发现对所有年龄段ANS敏锐度的有效测量具有启示意义，并表明Panamath协议产生的刺激不能充分控制凸包对数量辨别力的影响。
