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There is a theoretical disagreement in the working memory literature, with some proposing that the storage and processing of information rely on distinct parts of the cognitive system and others who posit that they rely, to some extent, on a shared attentional capacity. This debate is mirrored in the literature on working memory and aging, where there have been mixed findings on the ability of older adults to perform simultaneous storage and processing tasks. We assess the overlap between storage and processing and how this changes with age using a procedure in which both tasks have been carefully adjusted to produce comparable levels of single-task performance across a sample (N = 164) of participants aged 18-81. By manipulating incentives to perform one task over the other, this procedure was also capable of disentangling concurrence costs (single- vs. dual-task performance) from prioritization costs (relative payoffs for storage vs. processing performance) in a theoretically meaningful manner. The study revealed a large general cost to serial letter recall performance associated with concurrent performance of an arithmetic verification processing task, a concurrence cost that increased with age. For the processing task, there was no such general concurrence cost. Rather, there was a prioritization effect in dual-task performance for both tasks, irrespective of age, in which performance levels depended on the relative emphasis assigned to memory versus processing. This prioritization effect was large, albeit with a large residual in performance. The findings place important constraints on both working memory theory and our understanding of how working memory changes across the adult lifespan. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

From cockroaches to human beings, the presence of other members of the same species typically facilitates dominant (habitual/well-learned) responses regardless of their contextual relevance. This social facilitation requires special attention in animal species such as primates, given their evolved cognitive control mechanisms. Here we tested baboons who freely engaged in (computer-based) conflict response tasks requiring cognitive control for successful performance, and discovered that social presence does not only enhance dominant responses but also consumes cognitive control resources. Under social presence, the baboons experienced greater cognitive conflicts, were less able to inhibit a learned action in favor of a new one, and were also less able to take advantage of previous experience with response conflict, compared with isolation. These findings explain why inappropriate behaviors are not easily suppressed in primates acting in social contexts, and indicate a greater demand for cognitive control in social groups. This extra demand might represent a major evolutionary drive of human intelligence., (PsycINFO Database Record (c) 2014 APA, all rights reserved.)