Testing the effects of adolescent alcohol use on adult conflict-related theta dynamics

University of Minnesota M.A. thesis. February 2017. Major: Psychology. Advisor: William Iacono. 1 computer file (PDF); vii, 39 pages.While adolescent alcohol use (AAU) has been associated with poor neurocognitive outcomes, few studies have utilized prospective samples, leaving uncertain any potential long-term neurocognitive effects of AAU. In addition, despite theoretical models linking AAU to diminished cognitive control, empirical work testing the relationship between AAU and specific neural correlates of cognitive control remains scarce. Recent work indicates that demands of cognitive control (e.g., response conflict) involve EEG theta-band dynamics, including medial frontal cortex (MFC) power and MFC-dorsal prefrontal cortex (dPFC) functional connectivity, which may be related to AAU-related neurocognitive dysfunction. The present study tested the hypothesis that greater AAU is associated with diminished adult conflict-related EEG theta-band dynamics in a large (N = 718) population-based prospective twin sample assessed at the target ages of 11, 14, 17, and 29. Two complementary analytic methods (cotwin control design; bivariate biometric modeling) were used to disentangle the genetic/shared environmental premorbid risk towards AAU from the potentially causal nonshared environmental effects of alcohol exposure. AAU was negatively associated with adult (age 29) theta MFC power and MFC-dPFC connectivity during a flanker task, suggesting that early drinking is associated with diminished cognitive control-related theta dynamics in adulthood. Both the CTC and biometric modeling results indicated that genetic influences primarily accounted for the association between AAU and reduced theta-band dynamics. Taken together, these findings suggest that the link between AAU and diminished adult cognitive control-related theta dynamics is likely a consequence of heritable genetic factors, rather than causal nonshared environmental effects