Inattention and Hyperactivity Symptom Dimensions of ADHD Differentially Moderate the Relationship Between Concurrent...

ADHD has been characterised by excessive mind wandering (MW), or thoughts unrelated to the task at hand, with recent findings indicating that ADHD is specifically associated with more unintentional, but not intentional, MW. These two types of MW are also differentially associated with affective well-being. Most existing studies in ADHD, however, mainly rely on retrospective reports of MW tendencies, which are susceptible to memory-related errors and biases. Further, most studies categorise participants based on overall levels of ADHD, instead of accounting for the spectrum and dimensional heterogeneity of ADHD, including inattention and hyperactivity symptom dimensions. Our study aimed to address the knowledge gap regarding the relationship between different types of MW and affective well-being, across different symptom dimensions of ADHD.

We used ecological momentary assessment to capture participants' momentary attention state (on-task, intentional MW, or unintentional MW) and affective valence, six times daily for 7 days. Using linear mixed-effects modelling to account for inter-individual variance, we tested whether inattention and hyperactivity symptom dimensions of ADHD differentially moderate the relationship between attention states and affective valence.

We found that higher levels of inattention symptoms predicted more negative affect during intentional MW compared to on-task attention; in contrast, higher levels of hyperactivity symptoms predicted more positive affect during intentional MW compared to on-task attention.

Together, our results indicate that intentional MW moderates opposing effects of inattention and hyperactivity ADHD symptoms on affective valence. Our findings suggest that intentional MW - and not just unintentional MW - may also play a role in affective or behavioural outcomes associated with ADHD symptomatology, and highlight the importance of considering the heterogeneity of ADHD symptomatology, as well as the distinction between intentional and unintentional MW, in future ADHD research.