Cholesterol nose-to-brain delivery as a possible therapeutic strategy in Huntington's disease.

Childhood trauma is widely regarded as one of the most psychologically damaging forms of adversity because it occurs during a developmentally vulnerable period and often involves neglect or abuse perpetrated by caregivers (). In the present study, childhood trauma is conceptualized as caregiver-related maltreatment occurring during developmentally sensitive periods, encompassing the five forms assessed by the Childhood Trauma Questionnaire: emotional, physical, and sexual abuse, as well as emotional and physical neglect (). This operational definition deliberately centers experiences perpetrated or permitted within the caregiving relationship, rather than the broader spectrum of adverse childhood experiences (ACEs). Accordingly, while related forms of early adversity such as witnessing domestic violence, parental abandonment, or poverty-related hardship may co-occur with and compound maltreatment, they fall within the scope of the present conceptualization only insofar as they are expressed through these maltreatment dimensions. This distinction matters because the terms and are often used interchangeably. However, they are not equivalent: not all adversity is traumatic, and not all trauma arises from identifiable adversity. The Adverse Childhood Experiences (ACEs) framework casts a deliberately wide net, encompassing household dysfunction alongside abuse and neglect (). In contrast, Developmental Trauma and Complex Trauma frameworks foreground the chronic, interpersonal, and caregiver-bound nature of harm and its cumulative impact on emotional regulation, attachment, and self-organization (; ; ). The present study is positioned primarily within this latter tradition; its focus is not the full breadth of childhood adversity but the relational maltreatment that the complex trauma literature identifies as particularly consequential for later interpersonal and caregiving functioning. Framing the phenomenon in these terms clarifies why the fathers in this study are understood not simply as having endured difficult childhoods but as carrying relationally embedded wounds that are likely to be reactivated within the caregiving relationships they later form. Experiences of childhood trauma are highly prevalent worldwide and can negatively affect individuals’ physical, emotional, and psychological development (). A growing body of research indicates that the consequences of childhood trauma are not limited to the period in which they occur but may also lead to significant psychological outcomes later in life (). Individuals who have experienced childhood trauma may develop a range of psychological reactions, including identity disturbances, diminished self-esteem, intense feelings of guilt and shame, and anger toward those responsible for the traumatic experiences (; ). Moreover, childhood trauma has been strongly associated with a variety of psychopathological outcomes in adulthood, including depression, anxiety disorders, substance use problems, physical health difficulties, and functional impairments (; ). In recent years, the literature has increasingly emphasized that the impact of childhood trauma extends beyond individuals’ mental health and may also influence parenting behaviors and the developmental trajectories of subsequent generations. In particular, research has shown that parents’ childhood trauma is associated with higher parenting stress, reduced parental sensitivity, and lower-quality parent–child interactions (; ). These findings suggest that trauma should not be viewed solely as an individual experience but rather as a process that may be transmitted across generations within family systems. At the same time, an exclusive focus on psychopathological outcomes risks producing a deficit-oriented account that obscures an equally robust body of evidence. A substantial literature documents that many individuals exposed to childhood trauma do not go on to replicate harm and instead demonstrate resilience, recovery, and in some cases, post-traumatic growth, with protective factors and supportive relationships moderating the long-term impact of early adversity (; ). Within the parenting domain specifically, a history of childhood trauma does not determine caregiving outcomes. A considerable proportion of trauma-exposed parents become sensitive, reflective, and nurturing caregivers, and some appear to draw on their own histories as a source of motivation to parent differently (; ). Recognizing this heterogeneity is not merely a matter of balance; it is analytically necessary, because the conditions under which trauma is reproduced rather than interrupted are precisely what a study of fatherhood after childhood trauma must illuminate. The present study therefore adopts a deliberately non-deterministic stance, treating fatherhood as a context in which both the reactivation and the renegotiation of early experiences become possible. Parenthood represents a major developmental transition in adult life and ent