<p>Childhood maltreatment is a well-established transdiagnostic risk factor for psychopathology. Effective intervention requires a precise understanding of how distinct dimensions of adversity—neglect (deprivation) and abuse (threat)—uniquely shape emotion regulation. In a large, matched sample constructed using cardinality and optimal pair matching methods, we examined the differential associations between neglect, abuse, and their combination and a broad spectrum of emotion regulation difficulties and mental health outcomes including depression, anxiety, and suicide risk. Neglect was linked to a decreased use of regulatory strategies, reflecting a lack of essential developmental inputs. Abuse was associated with disrupted application of existing strategies, indicating interference with functional regulation. Critically, combined exposure to both neglect and abuse resulted in the most pervasive impairments across basic, cognitive, and interpersonal regulation. These findings support dimensional models of adversity and underscore the need for future research on trauma-specific interventions tailored to early-life experiences of threat and deprivation.</p>