Applied Problem Solving in Children with ADHD: The Mediating Roles of Working Memory and Mathematical Calculation

The difficulties children with ADHD experience solving applied math problems are well documented; however, the independent and/or interactive contributions of cognitive processes underlying these difficulties are not fully understood and warrant scrutiny. The current study examines two primary cognitive processes integral to children’s ability to solve applied math problems: working memory (WM) and math calculation skills (i.e., the ability to utilize specific facts, skills, or processes related to basic math operations stored in long-term memory). Thirty-six boys with ADHD-combined presentation and 33 typically developing (TD) boys aged 8–12 years old were administered multiple counterbalanced tasks to assess upper (central executive [CE]) and lower level (phonological [PH STM] and visuospatial [VS STM] short-term memory) WM processes, and standardized measures of mathematical abilities. Bias-corrected, bootstrapped mediation analyses revealed that CE ability fully mediated between-group differences in applied problem solving whereas math calculation ability partially mediated the relation. Neither PH STM nor VS STM was a significant mediator. When modeled together via serial mediation analysis, CE in tandem with math calculation ability fully mediated the relation, explained 79% of the variance, and provided a more parsimonious explication of applied mathematical problem solving differences among children with ADHD. Results suggest that interventions designed to address applied math difficulties in children with ADHD will likely benefit from targeting basic knowledge of math facts and skills while simultaneously promoting the active interplay of these skills with CE processes.     

Memory and metamemory for inverted words: illusions of competency and desirable difficulties

Research regarding how people monitor their learning has shown that ease of processing strongly guides people’s judgments of learning (JOLs). However, the desirable difficulties concept (Bjork, 1994) suggests that studying information that is less fluent can result in greater learning. Currently, it is unclear whether people are aware of the potential benefits of desirable difficulties during learning. To address this, in Experiment 1, participants studied inverted and upright words and also made JOLs. While participants’ JOLs did not differ for inverted and upright words, recall was greater for inverted words. Experiment 2 used several study–test cycles in which participants could potentially learn about the beneficial effects of processing inverted words with task experience, and similar results were obtained. Thus, reading inverted words requires processing that enhances recall, but memory predictions do not differentiate between upright and inverted words. We interpret these results in terms of processing fluency, desirable difficulties, and theories of metacognitive monitoring.