【Paper Review】Intergenerational Impact of Parental Adverse Childhood Experiences (ACEs) on Offspring Psychopathology

Posted on In Views: Disqus: Word count in article: 2.7k Reading time ≈ 10 mins.

I. Article Information

Title: 親の小児期逆境体験が次世代の精神病理に与える影響に関する研究の現状と課題
(Intergenerational Effect of Parental Adverse Childhood Experiences on the Next Generation’s Psychopathology: A Literature Review)

Authors: Keita Ishikawa, Natsuko Azuma, Mai Ohka, Ryu Takizawa
Affiliation: Graduate School of Education, The University of Tokyo; Institute of Psychiatry, Psychology & Neuroscience, King’s College London
Publication Year: 2022
Journal: The Japanese Journal of Developmental Psychology, Vol.33, No.2

II. Key Terms

2.1 ACEs (Adverse Childhood Experiences)

ACEs refer to adverse experiences encountered during ages 0-18. This concept was first introduced by Felitti et al. in 1998, encompassing two major categories:

(1) Abuse Experiences

  • Psychological abuse
  • Sexual abuse
  • Physical abuse
  • Physical neglect
  • Emotional neglect

(2) Household Dysfunction

  • Mental illness in household members
  • Domestic violence (father to mother)
  • Substance abuse by household members
  • Incarceration of household members
  • Parental separation or divorce

It should be noted that the definition of ACEs remains debated in academia. Some researchers argue that adversities experienced outside the home (such as bullying victimization, community violence) should also be included in ACEs, though Felitti et al.’s original definition primarily focused on adversities within the household.

2.2 Internalizing Problems

Internalizing problems refer to psychological and behavioral issues where individuals direct their psychological distress inward, primarily manifesting as emotional and affective difficulties. Typical internalizing problems include:

  • Depression: Persistent low mood, loss of interest, diminished self-worth
  • Anxiety: Excessive worry, fear, avoidance behavior
  • Withdrawal behavior: Social withdrawal, avoidance of interpersonal interactions
  • Somatic complaints: Physical discomfort without clear medical cause

Internalizing problems are often difficult for others to observe; children may appear quiet and compliant, making these issues easy to overlook. If not addressed promptly, such problems may develop into clinical-level mood disorders.

2.3 Externalizing Problems

Externalizing problems refer to instances where individuals express psychological distress through overt behaviors, manifesting as destructive or impulsive actions toward the external environment. Typical externalizing problems include:

  • Aggression: Physical aggression, verbal aggression, property destruction
  • Rule-breaking behavior: Violating rules, lying, stealing
  • Hyperactivity-impulsivity: Inattention, restlessness, impulsive behavior
  • Oppositional defiant behavior: Deliberate defiance, irritability, vindictiveness

Externalizing problems are relatively easy to observe because these behaviors directly impact others and the environment, often attracting the attention of parents and teachers more readily.

2.4 Behavior Problems

Behavior problems is a broader concept that encompasses both internalizing and externalizing problems, or refers to overall behavioral difficulties without type distinction. In some studies, when researchers do not subdivide children’s behavioral problems into internalizing and externalizing categories, they use this umbrella term.

2.5 DOHaD Hypothesis (Developmental Origins of Health and Disease)

The DOHaD hypothesis, proposed by Lucas in 1991, posits that health and nutritional status during fetal and early life periods (including early postnatal period) have long-term effects on adult health.

Specifically, this hypothesis suggests that:

  • Adverse factors in the intrauterine environment affect fetal organ development and metabolic system “programming”
  • These early biological changes increase the risk of chronic diseases in adulthood
  • Maternal physiological and psychological states during pregnancy affect fetal development through the placenta

In ACEs intergenerational transmission research, the DOHaD hypothesis is used to explain how maternal childhood adversity influences the next generation’s neurodevelopment and mental health through biological pathways during pregnancy.

2.6 HPA Axis (Hypothalamic-Pituitary-Adrenal Axis)

The HPA axis is the body’s primary stress response system, consisting of three endocrine glands: the hypothalamus, pituitary, and adrenal glands. Its mechanism works as follows:

  1. When an individual encounters stress, the hypothalamus releases corticotropin-releasing hormone (CRH)
  2. CRH stimulates the pituitary to release adrenocorticotropic hormone (ACTH)
  3. ACTH stimulates the adrenal cortex to secrete cortisol
  4. Cortisol helps the body cope with stress while regulating HPA axis activity through negative feedback

Chronic stress or childhood trauma may lead to HPA axis dysfunction, manifesting as:

  • Abnormal baseline cortisol levels (too high or too low)
  • Disrupted circadian rhythm of cortisol secretion
  • Excessive or blunted response to stress

In intergenerational transmission research, maternal ACEs may affect fetal neuroendocrine system development by altering HPA axis function during pregnancy.

2.7 Endophenotype

Endophenotype is an important concept in genetic epidemiology, referring to measurable biological or neuropsychological characteristics that lie between genotype and clinical phenotype. A valid endophenotype should meet the following criteria:

  1. Association with disorder: The characteristic is abnormal in patient populations
  2. Heritability: The characteristic is influenced by genetic factors
  3. State independence: The characteristic exists regardless of whether the disorder is active
  4. Cosegregation within families: The characteristic is co-inherited with the disorder in families
  5. Found in unaffected family members: The characteristic appears more frequently in healthy relatives of patients than in the general population

In psychiatric disorder research, endophenotypes help to:

  • Reduce heterogeneity of clinical diagnoses
  • Identify biological bases of disorders
  • Discover susceptibility genes for disorders
  • Provide objective indicators for early identification and intervention

2.8 Intergenerational Transmission

Intergenerational transmission refers to the phenomenon where certain characteristics, behavioral patterns, or disease risks are passed from one generation to the next. In ACEs research, intergenerational transmission specifically refers to how parental childhood adversity experiences affect their children’s physical and mental health and development.

Pathways of intergenerational transmission include:

  • Biological pathways: Through genetics, epigenetic modifications, prenatal maternal environment, etc.
  • Psychosocial pathways: Through parental mental health, parenting behaviors, family environment, etc.
  • Social structural pathways: Through transgenerational continuation of poverty, lack of social resources, etc.

Understanding intergenerational transmission mechanisms is crucial for breaking the vicious cycle of adversity and developing effective prevention and intervention measures.

2.9 Mediator (Mediating Variable)

A mediator is a variable that transmits the effect between an independent variable (such as maternal ACEs) and a dependent variable (such as offspring psychopathology). Mediators explain “why” or “through what mechanism” the independent variable affects the dependent variable.

In ACEs intergenerational transmission research, typical mediators include:

  • Maternal postpartum depression (maternal ACEs → postpartum depression → offspring behavior problems)
  • Parenting behaviors (maternal ACEs → inappropriate parenting → offspring psychopathology)
  • Prenatal physiological indicators (maternal ACEs → prenatal HPA axis abnormalities → offspring neurodevelopmental problems)

2.10 Moderator (Moderating Variable)

A moderator is a variable that affects the strength or direction of the relationship between independent and dependent variables. Moderators answer “under what conditions” or “for whom” the effect of the independent variable is stronger or weaker.

In ACEs intergenerational transmission research, typical moderators include:

  • Social support (high social support may attenuate the negative effects of ACEs)
  • Child gender (the effects of ACEs may differ by child gender)
  • Maternal education level (higher education may serve a protective role)

III. Research Background and Problem Statement

Core Concept: ACEs

Definition: Adverse experiences during ages 0-18, including:

  • Abuse experiences: Psychological abuse, sexual abuse, physical abuse, neglect, etc.
  • Household dysfunction: Family member mental illness, father-to-mother violence, parental divorce, etc.

Problems in Current Research

  1. Sufficient research on ACEs’ impact on individuals: Extensive research confirms ACEs increase physical and mental health risks in adulthood
  2. Insufficient research on intergenerational transmission: Mechanisms by which parental ACEs affect the next generation remain unclear
  3. Imbalanced research focus:
    • More research on intergenerational transmission of abuse alone
    • Less research on ACEs as a whole including household dysfunction

IV. Research Objectives

This study explores two core questions through literature review:

  1. Association between parental ACEs and offspring psychopathology
  2. Role of mediating and moderating variables during pregnancy and postpartum

The findings are compared with research on abuse experiences alone.

V. Research Methods

Literature Search Strategy

Search Period: 1998 (when the first ACEs study was published) to 2021

English Databases (3):

  • PubMed
  • PsycInfo
  • Web of Science

Search Terms: (“adverse childhood experience” OR ACE* OR “child adversity”) AND (intergeneration* OR “transgenerational cycle”)

Japanese Databases (3):

  • CiNii
  • Ichushi Web
  • J-Stage

Search Terms: “逆境体験” (adversity experiences)

Inclusion Criteria

  1. English or Japanese articles
  2. Research on intergenerational impact of parental ACEs
  3. Peer-reviewed original articles
  4. Child outcomes related to psychopathology variables

Final Results

  • English articles: 16 (selected from 230)
  • Japanese articles: 0 (from 178 screened)

VI. Overview of Study Characteristics

Study Distribution

  • Countries: United States (6), Canada (6), South Korea (2), Japan (1), Kenya (1)
  • Study Design: Cross-sectional studies (9), longitudinal studies (7, all birth cohort studies)
  • High-risk population studies: 8 studies focused on high-risk groups such as those in poverty, young age, social welfare recipients

ACEs Measurement Tools

Most commonly used scale: Felitti et al. (1998) ACEs scale (6 studies)

  • Abuse items (5): Physical abuse, sexual abuse, psychological abuse, physical neglect, emotional neglect
  • Household dysfunction (5): Cohabitant mental illness, substance use, incarceration, parental divorce, DV witnessing

Second most common: BRFSS ACEs scale (5 studies)

  • Removed physical and emotional neglect
  • Expanded sexual abuse perpetrators beyond parents

Special scale: Yale-Vermont Adversity in Childhood Scale (Rieder et al., 2019)

  • Only scale including adversities outside the home (e.g., war, disasters)

VII. Key Research Findings

I. Association Between Parental ACEs and Offspring Psychopathology

1. Externalizing Problems

Results: 9 of 11 studies (81.8%) found significant associations
Correlation coefficient range: r = 0.08 ~ 0.31 (most <0.30, small effect size)
Conclusion: Consistent and stable associations

2. Behavior Problems

Results: 3 of 3 studies (100%) found significant associations
Typical findings:

  • Maternal ACEs ≥2: Significantly increased risk of offspring behavior problems (Doi et al., 2021)
  • Parental ACEs ≥4: Offspring behavior problem risk OR=2.30 (Schickedanz et al., 2018)

3. Internalizing Problems

Results: 8 of 13 studies (61.5%) found significant associations
Correlation coefficient range: r = 0.04 ~ 0.33 (most <0.30, small effect size)
Conclusion: Inconsistent results

Important findings:

  • 3 studies found associations only with externalizing problems
  • 1 study found associations only with internalizing problems
  • Effect sizes generally small

4. Mental Disorders

Target disorders: ADHD (2 studies), PTSD (1 study)
Results: All found significant associations
Typical findings:

  • Maternal ACEs ≥3: Offspring PTSD prevalence OR=10.61 (Na et al., 2021)
  • Maternal ACEs ≥4: Offspring ADHD prevalence OR=2.07 (Schickedanz et al., 2018)

5. Temperament

Study: McDonald et al. (2019)
Findings:

  • Increased surgency/extraversion (OR=1.31)
  • Increased negative emotionality (OR=1.68)
  • No effect on effortful control (OR=1.27, not significant)

II. Mediators and Moderators of Intergenerational Transmission

Pregnancy Factors

1. Biological Factors (1 study)

  • HPA axis function (cortisol awakening response)
  • Mediation effect: Maternal ACEs → HPA axis function → offspring internalizing problems
  • Moderation effect: When cortisol secretion curve is flattened, ACEs’ impact on offspring increases

2. Psychosocial Factors (2 studies)

  • Prenatal anxiety: Mediates ACEs and offspring internalizing problems (Letourneau et al., 2019)
  • Prenatal psychosocial risk: Mediates ACEs and offspring emotional problems (Madigan et al., 2017)
  • Prenatal health risk: Mediates ACEs and offspring ADHD (Moon et al., 2021)

Postpartum Factors

1. Maternal Psychological Problems (7 studies, 100% found mediation effects)

  • Most frequently studied variable
  • Mediates for internalizing, externalizing, and behavior problems
  • Pathway: Maternal ACEs → postpartum depression/anxiety → offspring psychopathology

2. Parenting Behaviors (3 studies, 100% found mediation effects)

  • Physical punishment parenting style
  • Maternal irritability
  • Reduced positive parenting behaviors (making breakfast, eating vegetables)
  • Pathway: Maternal ACEs → inappropriate parenting → offspring behavior problems

3. Social Support (2 studies, 1 found effects)

  • Buffering effect: Family social support attenuates ACEs’ impact on offspring externalizing problems (Hatch et al., 2020)
  • No effect: Grandparental criticism showed no mediation (Yoon et al., 2019)

4. Attachment Type (1 study)

  • Insecure attachment mediates ACEs and offspring internalizing/externalizing problems

5. Other Factors

  • Child abuse experiences
  • Parental loss
  • Socioeconomic status (SES)

III. Gender Differences

Number of studies: 10 reported, 4 found gender differences

Difference patterns:

  1. Girls: Physical punishment → externalizing problems pathway significant (Yoon et al., 2019)
  2. Boys: More susceptible to ACEs effects producing internalizing/externalizing problems (Letourneau et al., 2019)
  3. Through HPA axis function:
    • Boys → externalizing problems
    • Girls → internalizing problems (Thomas-Argyriou et al., 2021)

VIII. Comparison with Abuse Experience Research

Similarities

| Dimension | ACEs Research | Abuse Experience Research (Plant et al., 2018) |
|–||-|
| Behavior Problems | 3/3 (100%) | 4/4 (100%) |
| Externalizing Problems | 9/11 (81.8%) | 4/5 (80%) |
| Internalizing Problems | 8/13 (61.5%) | 2/4 (50%) |
| Maternal Psychological Mediation | 9/9 (100%) | 7/8 (87.5%) |
| Parenting Mediation | 3/3 (100%) | 4/4 (100%) |

Core Findings

Both types of research show the same trends:

  • Consistent associations with externalizing problems/behavior problems
  • Inconsistent associations with internalizing problems
  • Psychosocial variables have robust mediation effects

Possible reasons:
The predictive power of household dysfunction for psychopathology is relatively weaker than abuse experiences (Atzl et al., 2019)

IX. Research Significance and Implications

Theoretical Significance

  1. Validates DOHaD hypothesis: Maternal ACEs affect fetal development through biological pathways during pregnancy
  2. Supports intergenerational transmission model: Psychosocial factors play a core role in ACEs intergenerational transmission
  3. Endophenotype potential: Prefrontal function may serve as an intermediate indicator connecting genetics and phenotype

Clinical Significance

  1. Early identification: Maternal ACEs can serve as risk indicators for offspring psychopathology
  2. Intervention windows:
    • Pregnancy: Focus on biological and psychosocial risks
    • Postpartum: Improve maternal mental health and parenting behaviors
  3. Multi-level intervention:
    • Individual level: Maternal psychotherapy
    • Relational level: Parenting skills training
    • Social level: Enhance social support

X. Study Limitations

Methodological Limitations

  1. Not a systematic review: Only a literature review, not meeting systematic review standards
  2. Limited databases: Only 6 databases, potentially missing relevant research
  3. Language restrictions: Only English and Japanese articles
  4. No effect size synthesis: Cannot conduct meta-analysis

Content Limitations

  1. Single outcome variable: Only focused on psychopathology, not covering physical health, developmental delays
  2. Insufficient research on adversities outside the home: Most studies focused only on home adversities (only 1 included bullying, etc.)
  3. Insufficient pregnancy research: Only 4 of 16 studies explored pregnancy factors
  4. Incomplete mechanism understanding: Did not fully explore gene-environment-epigenetic interactions

XI. Future Research Directions

1. Measure More Comprehensive Adversities

Polyvictimization Perspective

  • Integrate adversities inside and outside the home (e.g., bullying, war, disasters)
  • Examine cumulative effects of different context adversities
  • Explore specific associations between adversity types and offspring outcomes

Theoretical basis:

  • Individuals experiencing one type of harm are more susceptible to other harms
  • Multi-context victimization leaves individuals with no escape from threat

2. Strengthen Pregnancy Factor Research

Suggested research content:

  • Expand biological markers (not just HPA axis, but also immune system, epigenetic markers)
  • Pregnancy behavioral factors (smoking, substance use, nutritional status)
  • Placental function indicators (e.g., corticotropin-releasing hormone)

Study design:

  • Increase prospective birth cohort studies
  • Multi-timepoint tracking measurements
  • Integrate bio-psycho-social multi-dimensional data

3. Refined Mechanism Research

Multi-level model construction:

1
2
3
4
5
6
7
8
9
10
11
Genetic factors
    ↓
Epigenetic modifications ← Maternal ACEs
    ↓
Pregnancy biological changes
    ↓
Fetal neurodevelopment
    ↓
Postpartum environmental factors ← Parenting, social support
    ↓
Offspring psychopathology

Key questions:

  • Relative contributions of each level of factors
  • Sensitive periods at different developmental stages
  • Buffering mechanisms of protective factors

4. Develop Precision Intervention Strategies

Stratified intervention model:

  • High-risk identification: Risk stratification based on maternal ACEs scores
  • Personalized intervention: Customize intervention plans according to mediation mechanisms
  • Effect evaluation: Track intervention effects using biomarkers

XII. Key References

Foundational Studies

  1. Felitti et al. (1998) - First introduction of ACEs concept
  2. Hughes et al. (2017) - Meta-analysis of ACEs impact

Intergenerational Transmission Reviews

  1. Plant et al. (2018) - Systematic review of abuse experience intergenerational transmission
  2. Su et al. (2020) - Meta-analysis of intergenerational transmission

Mechanism Exploration

  1. Buss et al. (2017) - Intergenerational transmission model from DOHaD perspective
  2. Branje et al. (2020) - Gene-environment interaction theoretical framework

XIII. Summary and Reflection

Core Conclusions

  1. Parental ACEs do affect the next generation: Especially externalizing problems and behavior problems
  2. Intergenerational transmission has multiple pathways: Biological pathways (pregnancy) and psychosocial pathways (postpartum)
  3. Consistent trends with abuse research: Household dysfunction did not significantly change effect patterns
  4. Intervention opportunity windows exist: Both pregnancy and postpartum allow for intervention

Future Outlook

ACEs intergenerational transmission research is shifting from “whether it exists” to “how it occurs” and “how to prevent it”. By integrating multidisciplinary approaches (genetics, neuroscience, developmental psychology, epidemiology), we can potentially:

  • Establish more precise risk prediction models
  • Develop mechanism-based intervention plans
  • Break the intergenerational cycle of adversity

This is not only a scientific question but also an important public health issue.

Notes Compiled: 2025
Reference: Ishikawa et al. (2022). The Japanese Journal of Developmental Psychology, 33(2), 89-103.