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RATIONALE: Modafinil has been proposed as a potentially effective clinical treatment for neuropsychiatric disorders characterized by cognitive control deficits. However, the precise effects of modafinil, particularly on brain network functions, are not completely understood. OBJECTIVES: To address this gap, we examined the effects of modafinil on resting-state brain activity in 30 healthy adults using microstate analysis. Electroencephalographic (EEG) microstates are discrete voltage topographies generated from resting-state network activity. METHODS: Using a placebo-controlled, within-subjects design, we examined changes to microstate parameters following placebo (0 mg), low (100 mg), and high (200 mg) modafinil doses. We also examined the functional significance of these microstates via associations between microstate parameters and event-related potential indexes of conflict monitoring and automatic error processing (N2 and error-related negativity) and behavioral responses (accuracy and RT) from a subsequent flanker interference task. RESULTS: Five microstates emerged following each treatment condition, including four canonical microstates (A-D). Modafinil increased microstate C proportion and occurrence regardless of dose, relative to placebo. Modafinil also decreased microstate A proportion and microstate B proportion and occurrence relative to placebo. These modafinil-related changes in microstate parameters were not associated with similar changes in flanker ERPs or behavior. Finally, modafinil made transitions between microstates A and B less likely and transitions from A and B to C more likely. CONCLUSIONS: Previous fMRI work has correlated microstates A and B with auditory and visual networks and microstate C with a salience network. Thus, our results suggest modafinil may deactivate large-scale sensory networks in favor of a higher order functional network during resting-state in healthy adults.

Progress towards understanding neural mechanisms in humans relevant to psychiatric conditions has been hindered by a lack of translationally-relevant cognitive tasks for laboratory animals. Accordingly, there is a critical need to develop parallel neurophysiological assessments of domains of cognition, such as cognitive control, in humans and laboratory animals. To address this, we developed a touchscreen-based cognitive (Eriksen Flanker) task in rats and used its key characteristics to construct a novel human version, with similar testing parameters and endpoints across species. We obtained continuous electroencephalogram (EEG) recordings, including local field potentials in rats, and compared electrophysiological signatures locked to stimulus onset and responses across species. We also assessed whether behavioral or physiological task effects were modulated by modafinil, which enhances aspects of cognitive function in humans. In both species, the task elicited expected flanker interference effects (reduced accuracy) during high-conflict trials. Across homologous neuroanatomical loci, stimulus-locked increases in theta power during high-conflict trials as well as error-related negative potentials were observed. These endpoints were not affected by modafinil in either species. Despite some species-specific patterns, our findings demonstrate the feasibility of a rat Flanker task as well as cross-species behavioral and neurophysiological similarities, which may enable novel insights into the neural correlates of healthy and aberrant behavior and provide mechanistic insights relevant to treatment.

Etiological beliefs of depression have differing impacts on motivation, hope, and treatment expectations. However, it is unclear where people are exposed to these beliefs. Objective: This study examined beliefs about depression and their relations to symptoms, attitudes about depression, and treatment preferences. Participants: 426 undergraduates attending a large midwestern university. Methods: Participants completed an online survey asking about causes of depression, if and where they had heard about the "chemical imbalance" explanation of depression, attitudes about depression, as well as measures of their symptoms, treatment history, and hypothetical treatment preferences. Results: Sixty-two percent of the sample had heard of the chemical imbalance explanation, most commonly from the classroom. Biochemical beliefs about depression were most strongly endorsed among participants with a family history of depression and who had had personal experience with treatment. The chemical imbalance belief was uniquely related to dysfunctional beliefs about depression. Etiological beliefs were largely unrelated to treatment preferences. Conclusion: College students are exposed to models of mental health that may not be ideal for treatment and recovery. [ABSTRACT FROM AUTHOR]

This study explored developmental and individual differences in intellectual humility (IH) among 127 children ages 6-8. IH was operationalized as children's assessment of their knowledge and willingness to delegate scientific questions to experts. Children completed measures of IH, theory of mind, motivational framework, and intelligence, and neurophysiological measures indexing early (error-related negativity [ERN]) and later (error positivity [Pe]) error-monitoring processes related to cognitive control. Children's knowledge self-assessment correlated with question delegation, and older children showed greater IH than younger children. Greater IH was associated with higher intelligence but not with social cognition or motivational framework. ERN related to self-assessment, whereas Pe related to question delegation. Thus, children show separable epistemic and social components of IH that may differentially contribute to metacognition and learning.