Objective:Adverse childhood experiences (ACEs) is a broad construct that refers to negative events one may experience during childhood, including, but not limited to, childhood maltreatment, household dysfunction, and trauma. ACEs have consistently shown to be associated with negative physical and mental health outcomes. Although researchers have investigated the effects of trauma and abuse on personality measures, few studies have examined differences between those with high ACEs, low ACEs, and no ACEs on measures of personality in the context of neuropsychological evaluations.Participants and Methods:The current study included 128 consecutive adult patients referred for outpatient neuropsychological evaluation of attention-deficit/hyperactivity disorder. The sample was 39.8% non-Hispanic White, 21.9% non-Hispanic Black, 16.4% Hispanic, 10.9% Asian/Pacific Islander, and 10.9% other race/ethnicity, with a mean age of 27.9 years (SD=6.3) and mean education of 16.1 years (SD=2.2). Multivariate analyses of variance were performed to evaluate differences on the Minnesota Multiphasic Personality Inventory-2-Restructured Form (MMPI-2-RF) between individuals who experienced high levels of ACEs (>4/10 on the Adverse Childhood Experiences Questionnaire), low levels of ACEs (1-3/10), and no ACEs (0/10).Results:When analyzing Higher-Order (H-O) scales, there was a significant group difference in mean elevation on the Behavioral/Externalizing Dysfunction (BXD) scale, F(2,113)=3.124, p < .05, such that individuals in the high ACEs group evidenced higher scores than those in the low ACEs group (p < .05). Additionally, there were significant differences on several Restructured Clinical (RC) scales. Specifically, there were group differences on the Low Positive Emotions (RC2) scale, F(2,113)=3.427, p < .05, such that those in the low ACEs group evidenced higher scores than those in the no ACEs group (p < .05). The Antisocial Behavior (RC4) scale also had significant differences, F(2,113)=13.703, p < .001, such that those in the high ACEs group had higher scores than those in the low and no ACEs groups (p < .001). Finally, the Ideas of Persecution (RC6) scale yielded significant group differences, F(2,113)=4.793, p < .05, such that those in the high ACEs group evidenced higher scores than those in the low and no ACEs groups (p < .05).Conclusions:In sum, this study demonstrated that ACEs, particularly high levels of ACEs, are related to higher difficulties with problems with under-controlled and rule-breaking behaviors, low positive emotional responses, and beliefs that others pose a threat. As such, assessment of ACEs may serve an important role in characterizing patients’ psychological status as part of a comprehensive neuropsychological evaluation.