Schedule of Events | Symposia

Visuospatial Encoding in Adults with ADHD: Aperiodic vs. Periodic EEG Spectral Components

Poster Session B - Sunday, March 30, 2025, 8:00 – 10:00 am EDT, Back Bay Ballroom/Republic Ballroom

Talía V. Román-López^1,2, Fang Yu Chang^1,2, Holly Troung^1,2, Timothy Kelley^1,2, Joel P. Diaz-Fong^1,2, Andrea Dillon^1,2, Sandra K. Loo^1,2, Agatha Lenartowicz^1,2; ¹Semel Institute for Neuroscience and Human Behavior, University of California, Los Angeles, ²Department of Psychiatry and Biobehavioral Sciences, University of California, Los Angeles

In previous research, our group identified differences in the occipital alpha band (8–12 Hz) in children with Attention-Deficit/Hyperactivity Disorder (ADHD) (ages 7–14) during a visuospatial Sternberg working memory (SWM) task. During the encoding phase, children with ADHD exhibited reduced occipital alpha event-related decreases (ERD), consistent with a maturational delay. Older children with ADHD showed greater alpha ERD compared to younger ones, similar to developing (TD) children, indicating that this delay may diminish with age. This study revisited a subset of these participants, now adults, to assess whether alpha patterns observed during SWM encoding persist. In addition to EEG periodic patterns (alpha ERD), aperiodic (1/f) EEG components, including broadband exponent and offset, were analyzed. A total of 107 participants were included (TD: n = 42, mean age = 22.66 ± 8.96; ADHD: n = 65, mean age = 22.69 ± 7.0). Participants completed an SWM task with varying loads (1, 3, 5, or 7) while EEG was recorded. Age was included as a covariate in all analyses. Behaviorally, ADHD and TD groups did not differ significantly, but increasing task load led to slower reaction times and fewer correct responses. No group differences were observed in alpha power during encoding. However, ADHD participants showed higher aperiodic exponent and offset, with no load-related differences. These results suggest alpha activity in ADHD may normalize with age, reflecting visuospatial attention pathway maturation, while aperiodic components reveal persistent neural differences.

Topic Area: EXECUTIVE PROCESSES: Working memory