Iranian Journal of Learning and Memory

Abstract Objective: This exploratory, hypothesis-generating study investigated alpha-band EEG activity during resting state and cognitive task performance in adults with Attention-Deficit/Hyperactivity Disorder (ADHD) and examined its relationship with symptom severity, without a healthy control group. Method: EEG (8-12 Hz) was recorded in 28 adults with ADHD (21-31 years) during (1) eyes-closed rest and (2) a cognitive task requiring sustained attention. Absolute power and NeuroGuide z-scores were extracted. ADHD symptoms were assessed using the ASRS. Paired t-tests, Pearson correlations, and exploratory median split comparisons were performed. Results: Resting and task alpha activity were strongly correlated (r = .77, p < .01). At the group level, alpha activity unexpectedly increased from rest to task (t(27) = 2.34, p = .027). Linear correlations between ASRS total score and alpha activity at rest (r = .07) and during task (r = .20) were weak and non-significant (p > .05). In exploratory median-split comparisons (higher vs. lower symptom severity), individuals with higher severity showed significantly lower task-related alpha (t(26) = 2.12, p = .044, d = .81), but no significant difference in resting alpha (t(26) = 1.92, p = .066). Conclusions: In this hypothesis-generating study of adults with ADHD conducted without a neurotypical control group, we observed within-sample patterns of alpha modulation. The unexpected task-related alpha increase and the association between higher symptom severity and reduced task-related alpha warrant replication in larger, controlled studies with concurrent behavioral performance measures. No ADHD-specific conclusions can be drawn from this exploratory investigation.

Abstract The objective of the present study was to examine the relationship among sleep disorders, executive dysfunction, and sluggish cognitive tempo in adolescents utilizing a network approach. The study was performed based on descriptive-correlation method. The population of study contained all the adolescents (ages 12-18 years) in Tehran, Ardebil, Southern Azerbaijan and Western Azerbaijan provinces during 2021-2022 academic year. Data were collected from Two thousand six hundred and fifty-nine adolescents who were recruited through convenience sampling method. Participants completed the Adult Concentration Inventory (Becker et al. 2015), Sleep Disorders Symptom Checklist (Klingman et al. 2017), and Executive Skills Questionnaire-Revised (Strait et al. 2019). The bootnet package in R software used for data analysis. Results showed Sluggish Cognitive Tempo (SCT) was positively and more closely related to Sleep Disorders (insomnia) than Executive Dysfunction. the results showed that the most robust relative bridge connections were Sluggish Cognitive Tempo (SCT) and Plan Management (PM), edge weight = 0.33; Sluggish Cognitive Tempo (SCT) and Insomnia edge weight = 0.26; in addition to the positive bridge connections, a negative robust connection was also recognized between Obstructive Sleep Apnea (OSA) and Emotional Regulation (ER), edge weight = - 0.07. In conclusion, Sluggish Cognitive Tempo (SCT) was positively associated with sleep disorders and executive dysfunction. Future interventions may be developed that emphasize the bridge connections of sleep disorders, executive dysfunction, and sluggish cognitive tempo in adolescents