Comparing the neurocognitive effects of strattera and focalin on behavioral inhibition: An ERP study
Abstract
This project examined the effects of Dexmethylphenidate and Atomoxetine on behavioral and electro-physiological brain activity associated with behavioral inhibition (BI) in ADHD adults. Method. Young adults ( N = 29) diagnosed with ADHD were randomly assigned to a treatment regimen of Dexmethylphenidate, Atomoxetine, or psychotherapy. All participants engaged in the Stop-Signal task preand post-treatment. Response speed, latencies, accuracy, stop signal response times (SSRTs), and Event Related Potentials (ERP) served as outcome measures. Results: Pre-treatment weaknesses in oral language skills were observed. Exposure to overall treatment was associated with faster SSRTs and longer SOAs during successful inhibition. Post-treatment increases in right frontal N2 amplitudes, decreased parietal N2 amplitudes, and faster parietal N2 onset was observed. Post-treatment increase in frontal P2 amplitudes, and decreased central and parietal P2 amplitudes were also evident. No significant BI-related behavioral or ERP changes were observed in Atomoxetine-exposed participants. Dexmethylphenidate-exposed participants showed increased zenith N2 and P2 amplitudes, as well as right frontal N2 amplitudes during successful inhibition. Treatment with Dexmethylphenidate was associated with decreased parietal P2 amplitudes. Changes in P2 amplitudes most clearly distinguished the three treatment conditions. Conclusions. Overall treatment improved participants’ ability to anticipate environmental feedback and facilitated faster inhibition. Dexmethylphenidate notably affected BI-related frontal and parietal electrophysiology of ADHD adults, whereas Atomoxetine did not. Dexmethylphenidate effectively facilitated the function of fronto-parietal neural networks associated with preperceptual attentional and inhibitory processes. Dopaminergic, deep-brain basal ganglia circuits were implicated as central to BI-related deficits in young adults with ADHD.
Degree
Ph.D.
Advisors
Melara, Purdue University.
Subject Area
Clinical psychology|Cognitive psychology
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