Temperament and Child Psychiatric Disorders

Temperament: Risk and Protective Factors

Historical Antecedents

  • Galen's Four Temperament Types:
    • Sanguine: Extraverted and stable
    • Choleric: Extraverted and unstable
    • Melancholic: Introverted and stable
    • Phlegmatic: Introverted and unstable
  • Chess and Thomas:
    • Proposed nine basic dimensions of temperament.
    • Proposed three temperament types: easy, slow to warm up, and difficult.

Definition of Temperament

  • Mary Rothbart: "Constitutionally based individual differences in reactivity and self-regulation."
  • Key components of a temperamental trait:
    • Heritability: Genetic influence on the trait.
    • Stability: Trait is relatively stable across time.
    • Early appearance: Evident early in life, even in infancy.

Major Dimensions

  • Core dimensions are structured around incentive response systems (approach and withdrawal) often merged/crossed with emotional valence.
  • Common Dimensions:
    • Withdrawal and Propensity to Experience Negative Emotions: Threshold to experience negative emotions (sadness, fear, anger).
    • Approach and Positive Emotions: Degree to which a person actively engages the world and experiences positive emotions (joy, excitement).
    • Emotional Regulation and Constraint: Emotional and attentional regulation, especially when facing obstacles.
  • Other Dimensions:
    • Social Affiliation
    • Activity Level
    • Behavioral Inhibition and Disinhibition

Temperament Types

  • Emphasis on distinguishing groups with similar levels across traits.
  • The Difficult Child: (Chess and Thomas) Low rhythmicity, low response threshold and adaptability, and high-response intensity.
  • New Approaches to Temperament Types:
    • Moderate: Average levels across dimensions.
    • Steady: Low novelty seeking and high persistence.
    • Disengaged: High novelty seeking and harm avoidance, low reward dependence.

Features of Temperament

  • Observed in infancy and across cultures.
  • Sex Differences:
    • Women: Higher reward dependence and harm avoidance.
    • Men: Higher novelty seeking and persistence.
    • Girls: Higher effortful control, lower surgency, and equal negative affectivity.
  • Continuity:
    • Temperamental traits are moderately stable across time.
    • Physiologic "footprints" of traits may persist even without observable behavior.

Neurobiology and Etiology

  • Genetic Influences:
    • Twin and adoption studies suggest genetic factors explain 20-60% of variability in temperament.
    • Additive genetic influence is common; non-additive influence is less common.
  • Environmental Factors:
    • Shared environmental events: Have a similar effect on all members of a family.
    • Nonshared environmental factors: Environmental events that are not shared by members of the same family.
    • More support for unshared environmental effects.
  • Genetic–Environmental Interplay:
    • Bidirectional influences; environmental events can control gene expression.
    • Gene–environment correlations and interactions.
  • Neurotransmitters and Brain Circuitry:
    • Negative affectivity/harm avoidance: Amygdala and its pathways, HPA axis dysregulation.
    • Novelty seeking/extraversion: Dopamine pathways.
    • Social affiliation/reward dependence: Noradrenergic pathways, serotoninergic projections, oxytocin.
    • Persistence/effortful control: Anterior cortex, dopaminergic transmission.

Temperament and Psychopathology

  • Psychiatric symptoms exist on a continuum.
  • Impairment is a key consideration.
  • Models of Temperament/Psychopathology Associations:
    • Spectrum/continuum: Psychiatric disorders exist on a continuum with temperament traits.
    • Risk/vulnerability: Temperament increases the risk of psychopathology.
    • Common factor: Temperament and psychopathology share etiologic factors.
    • Pathoplastic: Temperament and psychopathology are distinct but have bidirectional influences.
    • Scar: Pathophysiology of psychiatric disorders alters temperament.

ADHD and Disruptive Behavior Disorders

  • Low effortful control and persistence, higher novelty seeking and extraversion.
  • Other disruptive disorders: Aggression, oppositionality.

Mood and Anxiety Disorders

  • Strongest association: Negative affectivity, neuroticism, or harm avoidance.

Autistic Spectrum Disorder

  • Low sociability/reward dependence, high negative affectivity, and low extraversion.

Other Disorders

  • Substance Use Disorders: Novelty/sensation seeking.
  • Eating Disorders: Low effortful control/persistence (bulimia), high neuroticism/harm avoidance.

Other Concepts in Temperament-Psychopathology Relations

  • Parenting Behavior: Transactional view with bidirectional influences.
  • Cognitive Factors: Moderating roles.
  • Trauma and Adverse Events: Can propel temperamentally at-risk children toward psychiatric symptoms.
  • Peer Groups and Activities: Can magnify maladaptive behaviors or channel tendencies productively.
  • Temperament and Resiliency: Protective factors in the face of adversity; can promote mental health and wellness.
  • Goodness of Fit: A cornerstone of child development theory.