Impact of Trauma on the Longitudinal Development of Cognitive Control Networks in Healthy Youth - Project Summary/Abstract Psychiatric disorders are the most prevalent debilitating illnesses across the lifespan. Importantly, epidemiologic studies indicate that 75% of all diagnosable psychiatric disorders begin prior to age 24, highlighting the need for investigations of the developing brain. Exposure to traumatic events during childhood and adolescence can induce maladaptive functioning of the hypothalamic-pituitary-adrenal (HPA) axis, leading to long-term structural and functional alterations in stress-sensitive brain regions that are known to be critical for cognitive control. Similar neural aberrations have been identified across a range of mental health disorders, including anxiety, ADHD, and depression. However, the extant literature focusing specifically on the impact of trauma and HPA axis activation on the development of cognitive control networks is extremely sparse. Given the high incidence of trauma in youth and ties with psychopathology, it is imperative that we develop a more detailed understanding of the neurophysiological changes underlying brain development in the context of trauma exposure. The proposed fellowship aims to partially remedy these knowledge gaps by utilizing the excellent spatial and temporal precision (i.e., millisecond) of magnetoencephalography (MEG) to investigate the developmental trajectory of brain networks critical to cognitive control and the impact of trauma and HPA axis activation on such networks. Briefly, participants between the ages of 6 to 15 years-old will annually complete a cognitive control task during MEG, complete cognitive and emotional assessments, and provide hair samples. The resulting MEG data will be transformed into the time-frequency domain and imaged using a beamforming approach, while the hair samples will be used to compute mean cortisol concentrations over 3 months. The output dynamic functional maps will be used to examine spectrally specific brain responses that are developmentally-sensitive in regions critical to cognitive control. Aim 1 will map the longitudinal development of neural dynamics and network connectivity that underlie response selection in typically-developing youth from age 6 to 15 years-old. Aim 2 will determine the impact of trauma exposure and HPA axis activation on the longitudinal development of cognitive control networks, neuropsychological performance, and emotional health. To this end, we will leverage the latest MEG and source reconstruction techniques, neural oscillatory dynamics and connectivity analysis methods, hair cortisol concentrations, and cognitive assessments to map variability in the neurophysiological bases of cognitive control development in healthy youth. In addition to the sponsor, who is a developmental cognitive neuroscientist with extensive mentoring and NIH funding experience, we will leverage an expert mentoring team comprised of leaders in cortisol analysis (Dr. Megan Gunnar), trauma assessment (Dr. Patrick Tyler), and the neuronal impact of childhood adversity (Dr. Christopher Monk). In summary, this research will aid in providing a more complete foundational understanding of the key neurological processes underlying cognitive control perturbations in youth with trauma and identify potential windows for intervention.