Please cite this article as: C.-T. Yang, S. Hsieh, C.-J. Hsieh et al., An examination of age-related differences in attentional control by systems factorial technology. Journal of Mathematical Psychology (2019) 102280, https://doi.org/10.1016/j.jmp.2019.102280. Journal of Mathematical Psychology xxx (xxxx) xxx Contents lists available at ScienceDirect Journal of Mathematical Psychology journal homepage: www.elsevier.com/locate/jmp An examination of age-related differences in attentional control by systems factorial technology Cheng-Ta Yang a,b,∗ , Shulan Hsieh a,b , Cheng-Ju Hsieh c , Mario Fifić d , Yen-Ting Yu a , Chun-Hao Wang e a Department of Psychology, National Cheng Kung University, Taiwan b Institute of Allied Health Sciences, National Cheng Kung University, Taiwan c Department of Chemical Engineering, National Cheng Kung University, Taiwan d Department of Psychology, Grand Valley State University, United States of America e Institute of Physical Education, Health and Leisure Studies, National Cheng Kung University, Taiwan article info Article history: Received 20 June 2018 Received in revised form 19 August 2019 Available online xxxx Keywords: Systems factorial technology Cognitive aging Workload capacity Parallel interactive model abstract A recent study by Ben-David et al. (2014) indicated that older adults process redundant targets with a larger workload capacity than younger adults, even though older adults exhibit generally slower response times (RTs). To investigate the organization of mental processes that underlie age-related differences, we conducted four experiments with redundant-target tasks. In a series of discrimination- type redundant-target tasks (Experiments 1–3), we replicated the age-related capacity advantage; however, the differences were eliminated in a detection-type redundant-target task (Experiment 4). Our results supported the distractor inhibition account, which suggests that age-related differences were due to less efficiency in attentional control to resolve the response conflict when making discrimination decisions. Moreover, we conducted a simulation using a Poisson parallel interactive model, which assumes an inhibitory interaction between two parallel channels that is a result of a limited attentional capacity. An analysis of the model’s predictions indicated the two key findings that may account for the age-related capacity differences: the older adults (1) processed the redundant targets with a higher decision criterion (i.e., more conservative in decision-making) and (2) exhibited a greater violation of context invariance (i.e., less degree of controlled attention in dealing with the response conflict). The extensive modeling analyses highlighted the effect of a decline in attentional control on age-related differences in workload capacity. © 2019 Elsevier Inc. All rights reserved. 1. Age-related differences in redundant-target signal process- ing In our daily life, we operate in a high-workload environment that forces us to divide attention between multiple sources of information to make decisions. An ecologically valid example is that an air control operator may fail to detect critical signals when false signals are simultaneously presented. To mimic this sce- nario, researchers developed a redundant-target task, which can be used to evaluate an individual’s capability of simultaneously monitoring multiple channels or displays. In one specific version of the redundant-target tasks, a trial may include two targets (redundant targets, e.g., XX), one target and one distractor (single target, e.g., XO or OX), or two distractors (no target, e.g., OO). With an OR stopping rule, an affirmative response is emitted ∗ Correspondence to: Department of Psychology, National Cheng Kung University, No. 1, University Rd., Tainan, 701 Taiwan. E-mail address: yangct@mail.ncku.edu.tw (C.-T. Yang). when any X is detected. In general, the response time (RT) in the redundant-target condition is faster than the faster RT of the two single-target conditions, referred to as a redundancy gain (RG) or redundant-target effect (RTE) (Miller, 1982). It is worth noting that the redundant-target task enables the assessment of the workload capacity, a theory-driven model-based index of the relative processing efficiency when the redundant targets are presented simultaneously to when a single target is presented alone (Townsend & Nozawa, 1995; Wenger & Townsend, 2000) (Please refer to the following section for the details regarding workload capacity). Despite its ecological pertinence, the redundant-target task, however, has less been studied in aging research than other forms of attentional tasks, such as switching tasks and flanker tasks (Rey-Mermet & Gade, 2018). Among the few available aging studies that used the redundant-target task, the RG has been found to be larger for older adults than younger adults (e.g., Allen, Madden, Groth, & Crozier, 1992; Linnet & Roser, 2012). One may conclude that the RG effect could provide a useful tool to study https://doi.org/10.1016/j.jmp.2019.102280 0022-2496/© 2019 Elsevier Inc. 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