‘The Trauma Is Coming From Inside the House': Unpacking the HITT Model

Featured Article

Traumatology | 2025, No. 2, pp. 243–251.

Article Title

Historical Intergenerational Trauma Transmission Model: A Comprehensive Framework of Family and Offspring Processes of Transgenerational Trauma

Authors

Claire J. Starrs - Department of Psychology, Université du Québec à Montréal

Vera Békés - Ferkauf Graduate School of Psychology, Yeshiva University

Abstract

The transgenerational impact of trauma is an emergent focus in the field of trauma research. A growing body of evidence suggests important consequences for the descendants of trauma survivors, at the individual, as well as the collective, and systemic levels. After a brief introduction to the main concepts and a summary of the key findings by population, the current article proposes a novel comprehensive model: the historical intergenerational trauma transmission model (HITT model). The HITT model comprises five higher order dimensions, including family vulnerability, offspring vulnerability, family resiliency, offspring resiliency, and historical moral injury. In addition, we propose insidious trauma as an important contextual variable that affects the impact of historical trauma (HT) on mental health and functioning. This is the first conceptual HT model designed to be applicable across populations, and that can be utilized by both researchers and clinicians. The components of the theoretical model, the research and clinical implications of this approach, as well as future directions are discussed.

Keywords

historical trauma, intergenerational trauma, trauma transmission, historical moral injury, insidious trauma

Summary of Research

“An increasing body of work focuses on the impact of traumatic events experienced by one generation on subsequent generations called intergenerational trauma (IT). This broad umbrella concept includes individual traumas, as well as collective or mass traumatic events that affect multiple generations of a group of people. Collective and systemic processes associated with historical, political, social, and cultural traumas, such as exploitation, oppression, and processes of colonization, also play an important role in transgenerational trauma. This type of collective multigenerational trauma is typically called historical trauma (HT)… Studies identifying mechanisms of transgenerational trauma transmission are scarce. The few that exist postulate individual processes such as anxious, angry, emotion-depleted parenting patterns, and collective mechanisms through discrimination and oppression…

The current article presents a comprehensive theoretical model for IT transmission stemming from historical, political, and social events, with the aim of integrating vulnerability and resiliency, as well as contextual factors…

The first aim of the current work is to summarize the key HT mechanisms of transmission by population suggested in the literature.
Secondly, we propose a comprehensive framework, capable of unifying these various processes, the historical intergenerational trauma transmission model (HITT model), which integrates family, descendant, social, and HT transmission processes” (p. 243- 244).

“Findings suggest that some factors may moderate the impact on future generations, such as the intensity of parental reaction to past trauma(s), number of traumatized parents, and parent gender…, existing studies have been restricted to examinations of clinical symptoms across generations or systemic mechanisms of discrimination and oppression, rather than comprehensive models… Although the majority of the population literature has focused on identifying vulnerability transmission processes, there are a few studies that discuss processes of resiliency across generations… Those studies point to several protective factors including in-group belonging and connectedness to cultural identity, the development of strong moral values, intrafamilial communication that is modulated in content and timing, as well as open communication about events and feelings.....Our proposed unifying model offers a complementary perspective to existing population-specific models and is not intended to replace them” (p. 244).

“...Existing studies have tended to focus on the intergenerational transmission of vulnerability; however, it is especially important from a prevention and intervention perspective, to also consider potential mechanisms of resiliency. Thus, we propose a comprehensive model, the HITT model that seeks to capture HT processes of risk and resilience, at the family, offspring, and societal levels. The HITT model comprises five higher-order dimensions,

(a) family vulnerability,
(b) offspring vulnerability,
(c) family resiliency,
(d) offspring resiliency,
and (e) historical moral injury (HMI)” (p. 245).

“When trauma is experienced by a large group of people, in contrast to feelings of distrust toward out-group others, there can also be a sense of in-group connection… This can be protective, as it reframes solitary experiences and histories into a larger, interconnected context… Solitary experiences can be contextualized within a group, and group experiences can come to be understood in connection with other groups…

HMI effects have been linked to higher anxiety and distress in survivors and their offspring, supporting our proposal that these processes exert direct and indirect effects on transgenerational trauma transmission…

We believe that the HITT model can fill this important role, as it provides a comprehensive empirically grounded framework for the understanding of HT factors that contribute to mental distress across generations” (p. 247- 248).

Translating Research into Practice

“We hope this model will allow researchers, educators, and clinicians to develop interventions and conduct investigations on broader questions about HT transmission without being constrained to a single population, and the related methodological limitations that have characterized previous research” (p. 244).

“Dalgaard et al. (2019) found that when survivors communicated the facts, reasons, and meanings behind their trauma, children were significantly less likely to show posttraumatic stress symptoms. Thus, parental sensitivity to the developmental level of the child, including the timing of disclosure, is modeled as a protective factor against transgenerational traumatization.…

Although trauma survivor families may use some less adaptive coping strategies, extrafamilial supportive relationships can foster adaptive coping and self-efficacy, helping to mitigate posttraumatic helplessness” (p. 245- 247).

“...It is important to recognize that the majority of clinicians working with persons who have experienced HT are not themselves members of the communities that they treat (e.g., refugees, Indigenous People)” (p. 248).

Other Interesting Tidbits for Researchers and Clinicians

“Overall, findings suggest that survivor parents communicate about their traumatic experiences, either too often, with too many details, or too little, with infrequent, and incomplete accounts leaving too much room for offspring imagination to fill in the gaps. Both extremes have been shown to have long-term negative impacts on descendants…

When the psychological boundaries between parent and child are blurred, children may identify with parental experiences and inner world, increasing their own distress… Dalgaard and Montgomery suggest a more optimal modulated disclosure style of intrafamily communication, where the timing and manner of disclosure, as well as parental sensitivity to developmentally appropriate cognitive and emotional needs of the child, are considered” (p. 245).

“...Given the existent evidence across different populations, it is not farfetched to hypothesize that other groups for whom history shows a pattern of collective traumatic experiences might also experience HT processes. Some possible groups include gender and sexual minority communities, neurodivergent, and/or disabled people” (p. 248).