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 Objective: This study aimed to examine the impact of rumination on both cognitive and sports performance, with sleep quality serving as a mediating factor.

Methods: The research was practical in purpose and employed a structural equation correlation design, conducted in a field setting. The statistical population consisted of all student athletes who participated in the table tennis tournaments in Khorasan in 2022, totaling 97 individuals. Sampling was performed using a census method, with 80 participants consenting to engage in the study. Data were collected using the rumination questionnaires developed by Nolen-Hoeksema and Morrow (1991), a sports performance scale by Charbonneau et al. (2001), a cognitive performance assessment by Folstein et al. (1975), and the Pittsburgh Sleep Quality Index (1989). For data analysis, Pearson's correlation coefficient and path analysis modeling were utilized.
Results: The findings indicated that rumination has a direct influence on both cognitive and sports performance (P=0.01). Furthermore, rumination significantly affects these performances indirectly through the mediation of sleep quality (P=0.01) among student athletes.
Conclusion: Based on the results of this study, rumination is correlated with cognitive and sports performance both directly and indirectly via sleep quality. It is recommended to engage a sports psychologist to conduct educational workshops on rumination management and to monitor and regulate the sleep patterns of student athletes.