Incidental and Intentional Object-Location Memory: The Effects of Stimulant Treatment on Adults with ADHD.

The relation between Attention Deficit/Hyperactivity Disorder (ADHD) and memory performance has attracted growing interest in recent years. However, one of the more complex memory abilities, object-location memory (OLM), remains scarcely studied within the context of ADHD. In this study, we examine incidental and intentional OLM performance in treated and untreated adults with ADHD and in controls. Fifty-eight adults with ADHD (26 medicated and 32 unmedicated) and 51 neurotypical individuals are assessed in a paper-and-pencil format for incidental and intentional OLM under a divided-attention condition. The results showed that all groups demonstrate higher performance in incidental OLM than in intentional OLM. Furthermore, medicated ADHD participants demonstrate reduced incidental OLM performance relative to unmedicated ADHD participants and controls. However, no group differences between unmedicated participants and controls are observed. This study reveals an overlooked aspect of visuospatial performance in ADHD under mental load and calls for further research on the impact of stimulants on incidental OLM.