This study is one of the first to examine associations between childhood trauma, Alzheimer’s genetic risk and APOEε4 dose with frontal EEG coherence (EEGc) in adolescence, as well as their joint association with PTSD and AUD in young adulthood. Results of the association between childhood trauma and EEGc were largely consistent with what was found in a related analysis (Neale et al., 2024), wherein childhood sexual assaultive trauma in females and childhood physical assaultive trauma in males were linked to differences in frontal alpha EEGc. Importantly, the present analyses also accounted for one of the largest genetic risk factors for Alzheimer’s disease, APOEε4, which is rarely examined in adolescent neurodevelopment despite evidence that cognitive differences related to APOEε4 (Chang et al., 2016; Iacono & Feltis, 2019) as well as trauma and alcohol use during adolescence (Carrion & Wong, 2012; Herringa, 2017; Lees, Meredith, Kirkland, Bryant, & Squeglia, 2020). We found that in both sexes, APOEε4 was associated with lower baseline EEGc and increased slope of EEGc, though these effects varied by brain region in males and females. Moreover, there were
