Analysis of Alpha Band Activity: Spatial Working Memory in Adults with ADHD

Poster Session D - Monday, April 15, 2024, 8:00 – 10:00 am EDT, Sheraton Hall ABC

Talía V. Roman Lopez^1,2, Holly Truong^1,2, Fang Yu Chang^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 our previous research, we identified alpha band changes in children (7-14 years old) diagnosed with Attention-Deficit Hyperactivity Disorder (ADHD) during a Sternberg spatial working memory (SWM) task. Compared to typically developing (TD) children, those with ADHD displayed diminished alpha desynchronization during encoding, particularly over the occipital region, consistent with a potential maturational lag in ADHD in visual attentional processes. This study revisited a subset of these individuals, now adults, to investigate whether the observed alpha band differences persist into adulthood. A total of 85 participants (34 TD/51 ADHD) with mean ages of TD = 25 (±6.7) and ADHD = 23.3 (±4.6) engaged in a SWM task with different loads (1, 3, 5, or 7), while EEG was recorded. ERSP was computed to analyze EEG signal-power changes throughout the trial between groups. Results revealed alpha desynchronization during encoding across Frontal, Central, Parietal, and Occipital scalp regions. This pattern was load-sensitive, replicating earlier findings and supporting alpha as a reliable attentional marker in working memory. However, significant differences between ADHD and TD were observed in parietal electrodes, but not over occipital electrodes as seen in childhood, with no group-by-load interactions in any region. The data suggest a tendency for alpha normalization in the occipital region among ADHD adults, possibly reflecting cortical response maturation. However, the disparity in the parietal region suggests a potential reorganization in cortical network processing during encoding in adulthood. These findings contribute to our understanding of neural dynamics in ADHD individuals.

Topic Area: EXECUTIVE PROCESSES: Working memory