Transgenerational trauma, or intergenerational trauma is the psychological effects that the collective trauma experienced by a group of people has on subsequent generations in that group. Collective trauma is the effect of psychological trauma experienced by communities and identity groups and carried as part of the group's collective memory and shared sense of identity. For example, collective trauma was experienced by Jewish Holocaust survivors and other members of the Jewish community at the time, and by the First Peoples of Canada during the Canadian Indian residential school system. When this collective trauma affects subsequent generations, then it is called transgenerational trauma. For example, if Jewish people experience extreme stress or study survivalism out of fear of another Holocaust, despite being born after the end of the Holocaust, then they may be coping with transgenerational trauma.
Transgenerational trauma is a collective experience that affects groups of people because of their cultural identity (e.g., ethnicity, nationality, or religious identity). Because of its collective nature, the term is not usually applied to single families or individual parent–child dyads. However, like survivors of individual child abuse, individually, both direct survivors of the collective trauma and members of subsequent generations may develop complex post-traumatic stress disorder.
This field of research is relatively young, but has expanded in recent years. The mechanism for transmission of trauma may be socially transmitted (e.g., through learned behaviors), through the effects of stress before birth, or perhaps through stress-induced epigenetic modifications.
History
Intergenerational trauma was first recognized in the children of Holocaust survivors. In 1966, psychologists began to observe large numbers of children of Holocaust survivors seeking mental help in clinics in Canada. The grandchildren of Holocaust survivors were overrepresented by 300% among the referrals to a psychiatry clinic in comparison with their representation in the general population.
Since then, transgenerational trauma has been noted amongst descendants of African-Americans forced into slavery, Native American genocide survivors, war survivors, refugees, survivors of domestic violence, and many other groups that have experienced collective distress.
Aside from populations, the Human Genome Project helped determine that any individual who undergoes extreme stress is susceptible to pass on these epigenetics to genetic offspring.
Historical trauma
Historical trauma is considered a sub-type of transgenerational trauma.
Instances of transgenerational trauma where the trauma is a shared experience amongst a group of people and their role in society, are often referred to as historical trauma. In general, historical trauma consists of three factors: the widespread nature, traumatic events resulting in a collective suffering, and the malicious intent of those inflicting the trauma. This form of trauma is specific as it affects a large population and is typically more complex than individual trauma. Historical trauma can result in a greater loss of identity and meaning, which in turn may affect generations upon generations until the trauma is ingrained into society.
Building upon the clinical observations by Selma Fraiberg, child trauma researchers such as Byron Egeland, Inge Bretherton, and Daniel Schechter have empirically identified psychological mechanisms that favor intergenerational transmission, including dissociation in the context of attachment, and "communication" of prior traumatic experience as an effect of parental efforts to maintain self-regulation in the context of post-traumatic stress disorder and related alterations in social cognitive processes.
Symptoms
Symptoms of intergenerational trauma always begins with the survivor of a trauma, which tend to manifest as symptoms of PTSD. Oftentimes trauma in the second generation is deemed as a traumatic response to parental trauma. Transmission between the parent and child can be broken down into 5 measures: communication, conflict, family cohesion, parental warmth, and parental involvement. High levels of maternal stress were directly correlated with weak family functioning and indirectly correlated with deviant behavior among children. Common symptoms in children consisted of depression, antisocial behavior, delinquency, and disruptive behavior in school. Some children experienced direct transmission in which their trauma stemmed from the interactions and relationships with their parents, while others experienced indirect transmission in which their trauma was mainly rooted in guilt. Those who were affected through direct transmission were more likely to lash out through their actions, while those who were affected through indirect transmission were more likely to suffer from depression, anxiety, and guilt.
Symptoms also differed based on ethnicity and type of original trauma. Enslavement, genocide, domestic violence, sexual abuse, and extreme poverty are all common sources of trauma that lead to intergenerational trauma. A lack of therapy also worsens symptoms and can lead to transmission. For instance, survivors of child sexual abuse may negatively influence future generations due to their past unresolved trauma. This can lead to increased feelings of mistrust, isolation, and loneliness. Descendants of slaves when faced with racism-motivated violence, microaggressions, or outward racism, react as if they were faced with the original trauma that was generationally transmitted to them. There are a variety of stressors in one's life that led to this PTSD-like reaction such as varying racist experiences, daily stressors, major race-related life events, or collective racism or traumas. This also presents itself in parenting styles. Goodman and West-Olatunji proposed potential transgenerational trauma in the aftermath of natural disasters. In a post-Hurricane Katrina New Orleans, residents have seen a dramatic increase in interpersonal violence with higher mortality rates. This phenomenon has been also been reported in the descendants of Indigenous students at residential schools, who were removed from their parents and extended family and lacked models for parenting as a result. Being punished for speaking their native language and forbidden from practicing traditional rituals had a traumatic effect on many students, and child abuse was rampant in the schools as well.
Symptoms of transgenerational trauma have in recent years been identified among Black Americans, in relation to the effects of slavery and racial discrimination. This passing of trauma can be rooted from the family unit itself, or found in society via current discrimination and oppression. The traumatic event does not need to be individually experienced by all members of a family; the lasting effects can still remain and impact descendants from external factors. For example, Black children's internalization of others' reactions to their skin color manifests as a form of lasting trauma originally experienced by their ancestors. This reaction to Black skin stems from similar attitudes that led to the traumatizing conditions and enslavement of slaves. Black children and youth are more susceptible to racial trauma because they have not yet acquired the knowledge to have a full understanding of racism and its effects. However, these traumatizing behaviors experienced at such a young age are a reflection of a child's parenting. A White child may learn racist behaviors from their environment, but on the same token a Black child can learn to assert their blackness and how to respond to racist remarks and actions from their parents. Traces of trauma have an impact on Black and other minority children's success in an educational context. Transgenerational trauma has also been heavily recorded in refugees and their children, which can last through several generations. Such traumas can stem from violence, political persecution, familial instability, as well as the hardships of migration.
Affected groups
Descendants of Enslaved People
In recent years, symptoms of transgenerational trauma has been identified among Black Americans, in relation to the effects of slavery and racial discrimination. This passing of trauma can be rooted from the family unit itself, or found in society via current discrimination and oppression. The traumatic event does not need to be individually experienced by all members of a family; the lasting effects can still remain and impact descendants from external factors. For example, Black children's internalization of others' reactions to their skin color manifests as a form of lasting trauma originally experienced by their ancestors. This reaction to Black skin stems from similar attitudes that led to the traumatizing conditions and enslavement of slaves. Black children and youth are more susceptible to racial trauma because they have not yet acquired the knowledge to have a full understanding of racism and its effects. Traces of trauma have an impact on Black and other minority children's success in an educational context. Trangenerational trauma has also been heavily recorded in refugees and their children, which can last through several generations. Such traumas can stem from violence, political persecution, familial instability, as well as the hardships of migration.
In general, Black Americans who suffer from any mental illness are resistant to receiving treatment due to stigma, negative conceptions, and fear of discrimination. This reduces the number of those affected to seek help. Lack of treatment causes the symptoms to compound leading to further internalization of distress and a worsening of mental health in the individual. Those affected by race-based trauma oftentimes do not seek treatment not only because of stigma but because of fear that the medical professional will not understand their perspective of a disenfranchised minority. Furthermore, the existing stigma of mental health has led to a lack of research and consequently treatment. However, lack of treatment can also be attributed to the misdiagnosis of symptoms. Signs of trauma exhibited in Black children are often labeled as behavioral or educational disabilities, allowing the trauma to go untreated. While trauma symptoms often manifest as other mental illnesses such as depression and anxiety, the larger diagnosis often goes untreated.
This form of trauma, however, must be understood not as a personal plight, but as a form of cultural trauma as it affects one’s "sense of group identity, values, meaning and purpose".
Koreans
Han is a concept of an emotion, variously described as some form of grief or resentment, among others, that is said to be an essential element of Korean identity by some, and a modern post-colonial identity by others.
Michael D. Shin argues that the central aspect of han is loss of identity, and defines han as "the complex of emotions that result from the traumatic loss of collective identity". Han is most commonly associated with divided families: families who were separated during the Korean War. According to Shin, all Koreans may experience han, or a "constant feeling of being less than whole", because of not having a collective identity as a result of the continued division of Korea. Furthermore, new generations of Koreans seemingly inherit it because of growing up in a divided country.
Refugees
One group of people that is often at risk of experiencing transgenerational trauma is refugees. While all refugees experience some sort of loss and trauma, war-related trauma has been documented to have longer lasting effects mental health and span through more generations. Children are especially prone to the trauma of resettling, as their childhood has been disrupted by a migration to a new country. They also often face the difficulty of learning a new language, adapting to a new environment, and navigating the social system of school in their host country. Normal caregiving is disrupted by the process of fleeing from their original home, and it may continue to be disrupted by their parents' PTSD symptoms and challenges faced in their new home. Furthermore, most host countries, do not provide an adequate mental healthcare systems to refugees which can worsen symptoms and lead to transmission of trauma. In general, children of refugees overall had higher levels of depression, PTSD, anxiety, attention deficiency, stress, and other psychological issues.
Cambodian
Since 1975, the US has accepted many refugees from Vietnam, Cambodia, Thailand, and Laos. While majority of these groups were fleeing war and poverty, Cambodian refugees were also fleeing a genocide from the Khmer Rouge. The atrocities of violence, starvation and torture were common themes experienced by these refugees. Many Cambodian refugee families refused to talk about their trauma creating an isolating environment for the child. This led to a transmission of trauma and through the continuing pattern of silence and refusal to acknowledge an issue or seek treatment. There has also been data showing that the children of survivors from regions with higher rates of violence and mortality displayed stronger overall symptoms. Parenting style of caregivers may also contribute to the rate of impact among children of Khmer Rouge survivors. A 2013 study found that among Khmer Rouge survivors with PTSD who engage in role-reversal parenting, a form of parenting where the parent looks to the child for emotional support, there may be higher rates of anxiety and depression in the children.
Transmission
Transmission during pregnancy
Another major way that stress can be transmitted across generations biologically is through the uterine environment. The gestational stage is a developmentally sensitive stage in an individual's lifespan. Exposure to harmful stimuli during this stage can have long-lasting, detrimental effects. The uterine environment with its unique blend of the mother's cellular secretions and proteins is a major source of stimuli. Empirical evidence has shown that trauma experienced by a mother during pregnancy can affect offspring's physiology and psychology. One possible method of transmission is through transport vesicles transferring amino acids and microRNA from the uterine fluid to the fetus. These molecules may then alter gene expression in a way that affects the developmental trajectory of the fetus. Most biological research on transgenerational trauma has focused on the hypothalamic-pituitary-adrenal (HPA) axis, which is the center of the body's stress response system. One way the HPA axis responds to stress is by triggering the production of glucocorticoids, primarily cortisol. Cortisol triggers “fight-or-flight” physiological symptoms like increased blood pressure and heart rate. In animal models, maternal stress and trauma during pregnancy has been shown to reduce the expression of placental enzyme 11B-hydroxysteroid dehydrogenase type 2 (11 β-HSD2), which converts the mother's cortisol to inactive cortisone. This leads to increased fetal exposure to the mother's glucocorticoids, which affects the development of glucocorticoid-sensitive systems like the HPA axis. In some studies, abnormal cortisol levels compared to controls and alterations in DNA methylation were observed in infants of mothers who endured trauma while pregnant, particularly in the NR3C1 glucocorticoid receptor gene.
Psychological and social aspects
There are many current transgenerational studies that have been done on adults that have experienced natural disasters or adversities. One study found that the children of torture victims showed more symptoms of anxiety, depression, post‐traumatic stress, attention deficits and behavioral disorders compared with the comparison group of those who had not experienced the specific trauma. A qualitative study was done on the Brazilian children of Holocaust survivors. This study was able to propose not only a supported model of the transgenerational transmission of traumatic experiences, but one also of resilience patterns that can be transmitted in between generations and developed within generations. According to Walsh, Resilience Theory suggests that individuals' and families' responses to traumatic experiences is an ever-changing process that involves both exposure to challenges and the development of coping mechanisms that aide in one's ability to overcome such challenges. Regardless of risk, there also exists opportunities for the development of resilience via exposure to meaningful resources that support one's ability to overcome adversity. Researchers Cowan, Callaghan, & Richardson studied the impact of early-life adversities on individuals and their descendants. Their research was also consistent with the transmission theory, in which their findings revealed that the stress phenotype that was expressed in individuals who experienced the adversity was also observed in children and even grandchildren.
The famous study of Harlow's monkeys also revealed that the adversity of a maternal variable which would create stress in the individual was also witnessed in their offspring although not having experienced the adversity. One last study displayed that if children were exposed to high postnatal maternal licking/grooming and arched-back nursing then they were likely to do the same to their offspring. Vice versa, if children experienced low LG-ABN mothers, then they were likely to provide the same to their offspring. Consequently, this causes a decrease in serotonin and expression, and an increase in methylation. Ultimately, a more stressed pup is created, causing this phenotype to be passed on through experience and genes.
Theses studies allude to the fact that oftentimes adversity, especially early on and for longer periods of time, can impact development in individuals and their offspring.
The oppression that black people experienced through slavery and racism has a psychological impact on how they view achievement. In terms of the social aspects of this, seem to make it difficult for black people to surpass a certain SES threshold, to escape a certain neighborhood, to move beyond a certain lifestyle or status.
For Native Americans, past government policy and internal displacements are theorized to have an effect generations later. The social enforcement of their ostracization causes them to be generally removed from society, to be powerless and uninvited in government, and to be left to fend for themselves. The transgenerational transmission of colonial trauma is also considered a contributing factor in the high rates of mental health difficulties Canadian Indigenous communities experience. Displacement and maltreatment during colonization had led to negative effects in the children of Indigenous peoples who survived such experiences. This is passed down generationally via ongoing social marginalization and lateral violence. The loss of Indigenous cultures and resulting lack of community cohesion poses a further challenge for Indigenous groups in resolving transgenerational trauma.
Treatment
Like all other mental disorders, the key to preventing transgenerational trauma is to recognize the issue and to intervene before transmission occurs. Because intergenerational trauma often stems from other issues, it is often unrecognized or misdiagnosed by clinicians. Moreover, there is a lack of trauma therapy specialists in the US which further affects treatment. A lack of treatment has many consequences such as health, behavioral, and social issues that can persist throughout the child's life.
In more complex intergenerational trauma diagnoses, the Transgenerational Trauma and Resilience Genogram (TTRG) can be helpful to clinicians to fully grasp the situation. The TTRG maps out the family unit, marking those who have experienced trauma and their experience, as well as relationships between individuals, and patterns of functioning.
Criticism
Professor of genetics and neuroscience Kevin Mitchell argues that a mechanism for transgenerational trauma is implausible, and that many have looked at it as a “get out of genetics free card”, adding "I think people don't like the idea, some people anyway, that we are born with certain predispositions that are hard to change". Mitchell says that experiences are expressed through changes in human neuroanatomy, not patterns of gene expression. He says that scientists in this area have contributed to the misleading research in this area: "There is a hype industry around science, which I think is corrosive. And I think scientists are willing participants in it in a way that I find more and more distasteful the older I get, because it does a massive disservice cumulatively to how science is understood by the general public because we have this constant hype".
Biologist Ewan Birney criticised a paper entitled 'Holocaust Exposure Induced Intergenerational Effects on FKBP5 Methylation' which used a sample size of 32 people to back its claim that children of Holocaust survivors showed evidence of inherited stress. He argues that 'It is particularly difficult to show true trans-generational inheritance in humans' and thus it is hard to prove that Trans-generational epigenetic inheritance can apply to mammals commonly due to the numerous factors including 'complex societal forces that persist over time'.
