(PS1-73) Avoidant Automatic Thoughts Mediate the Relationship Between ADHD Symptoms and Subsequent Inattention and Task Avoidance: Investigating the Role of Perceived Stress

Two prior Ecological Momentary Assessment (EMA) studies (Knouse et al., 2023; Knouse et al., 2025) concluded that participants with more severe ADHD symptoms experience more frequent avoidance automatic thoughts (AAT)— thoughts that accompany a delay in starting or ending a task—and that AAT is associated with increased inattention and task avoidance. However, whereas AAT moderated the relationship between ADHD symptoms and inattention/task avoidance in a community sample (Knouse et al., 2025), such moderation was absent in a college sample (Knouse et al., 2023). Additionally, prior research indicates associations between stress and both inattention (Combs et al., 2015) and task avoidance (Öster et al., 2020). The current study replicated and extended this research in a sample of college students with and without ADHD, predicting that AAT mediates rather than moderates the relationship between ADHD symptoms and inattention/task avoidance, with perceived stress mediating this relationship through its impact on AAT. 97 undergraduates participated (Mage = 19.99; 72% women, 21% men, 7% other gender identities; 18% Asian, 6% Black, 1% Native American, 61% White, 14% Other; 16% Hispanic/Latinx), meeting ADHD or non-ADHD screening criteria based on the Barkley Adult ADHD Rating Scale-IV (45 ADHD, 52 non-ADHD). Participants first completed a baseline questionnaire, including measures of ADHD symptoms (BAARS) and perceived stress (Perceived Stress Scale), and then completed six days of EMA five times per day, including measures of momentary AAT (ADHD Cognitions Scale-10), task avoidance, and inattention (BAARS). Pre-registered analyses were conducted in R and SPSS. Time 2 AAT, task avoidance, and inattention scores are calculated by averaging every timepoint based on each individual. Simple mediation analyses using Hayes' PROCESS model 4 revealed significant partial mediations as predicted: AAT partially mediated the relationship between baseline ADHD symptoms and mean momentary inattention (indirect effect = .2827, CI [.1490, .4419]) and task avoidance (indirect effect = .2909, CI [.1389, .4571]). Perceived stress also showed significant partial mediation between ADHD symptoms and inattention (indirect effect = .1511, CI [.0314, .2829]) and task avoidance (indirect effect = .1985, CI [.0232, .1810]). Furthermore, serial mediation analyses using model 6 demonstrated that ADHD symptoms indirectly influenced inattention (indirect effect = .0858, CI [.0725, .3378]) and task avoidance (indirect effect = .0851, CI [.0211, .1808]) through stress and subsequently through AAT. This study replicates prior findings regarding ADHD associated with more frequent avoidant thoughts, while avoidance thoughts and stress are both associated with a higher likelihood of inattention and task avoidance. The study concluded that stress and AAT mediate the relationship between ADHD symptoms and both momentary inattention and task avoidance, while stress is associated with AAT. Future research should investigate the efficacy of stress regulation and AAT awareness in improving inattention and task avoidance, especially for clients with ADHD.