Overview
A client came to me a few years ago with what looked, from the outside, like ordinary high- functioning anxiety. She was thirty-two, second-generation Iranian-Canadian, born in Vancouver. She had a successful career, a healthy marriage, no obvious trauma history. She had been doing CBT for two years and had not gotten meaningfully better. She came to me because someone had told her my work was different.
In our fourth session, while she was talking about something unrelated, her body went still. She told me she had a sudden, vivid sensory memory of an apartment in Tehran she had never lived in. The smell of it. The feel of the tile under bare feet. The light coming through a particular window.
Her grandmother sitting somewhere just out of view. She had never been to that apartment. Her mother had described it once, twenty years ago. But her body had it. This is intergenerational trauma. It is real, increasingly understood scientifically, and one of the most under-recognized clinical realities in our work with the children and grandchildren of trauma survivors.
What we mean by intergenerational trauma Intergenerational trauma — also called generational trauma, transgenerational trauma, or inherited trauma — refers to the transmission of trauma effects from one generation to the next, even when the second or third generation did not directly experience the originating events.
The transmission happens through several mechanisms
Attachment patterns. Children of traumatized parents are raised by adults whose nervous systems were shaped by trauma. The traumatized parent, however loving, may be hypervigilant, emotionally avoidant, prone to flooding, or numbed. The child's nervous system is shaped, in early development, by the parent's regulated and dysregulated states. This is not parental failure; it is biology.
Family environment and unspoken rules. Households shaped by trauma have particular features — what can be talked about, what cannot, where the silences live, what triggers protective reactions. Children absorb these rules without being taught them.
They become the air the family breathes. Specific behavioural and emotional patterns transmitted through modeling — anxiety responses, hyper-vigilance, the relationship to risk, the relationship to authority, the relationship to safety. Cultural and historical narrative carried in the family's stories, silences, and reactions to current events. Increasingly recognized: epigenetic transmission.
Research over the past two decades has shown that severe trauma can produce epigenetic changes — modifications to how genes are expressed, without changing the genetic code itself — that can be passed to offspring.
Studies of Holocaust survivors' descendants, descendants of the Dutch Hunger Winter, descendants of trauma survivors more broadly, have shown measurable changes in stress response systems in people who never experienced the original trauma. This is not metaphor. It is biology. What Iranian families often carry For Iranian families specifically, the historical material that may have shaped the family system is significant.
The decades around the 1979 revolution and the Iran-Iraq war (1980–1988) produced extensive trauma — for those who lived through them, for the families displaced, for those who lost loved ones, for those who fled, for those who stayed.
Many of my clients' parents and grandparents lived through these years. Many do not talk about them. Many cannot. The specific material commonly transmitted through Iranian families includes: War trauma. Bombings, mobilization, missing or martyred relatives, the lived experience of a country at war during formative years. Many of my clients' fathers were boys during the Iran-Iraq war and have never fully spoken of what they saw. Displacement trauma.
The trauma of leaving — sometimes urgently, sometimes incrementally — homes, professions, family networks, identities. Even for families who immigrated under relatively stable conditions, the displacement carries cost. Political trauma.