temperament Flashcards
What is the rationale behind using twin studies in behavioral genetics?
Twin studies allow researchers to estimate the relative contributions of genetic (A), shared environmental (C), and non-shared environmental (E) factors to individual differences in traits by comparing resemblance between monozygotic (MZ) and dizygotic (DZ) twins.
What is the difference between MZ and DZ twins in terms of genetic similarity?
- MZ (Monozygotic) twins share ~100% of their genes.
- DZ (Dizygotic) twins share ~50% of their genes, like regular siblings.
Define the ACE model in twin studies.
- A (Additive genetic factors / Heritability)
- C (Common/shared environmental influences)
-
E (Non-shared/unique environmental influences)
The phenotype (P) = A + C + E
How are the ACE components calculated?
Heritability (A) = 2(rMZ – rDZ)
Shared Environment (C) = rMZ – A
Non-shared Environment (E) = 1 – rMZ
What do rMZ and rDZ represent in twin studies?
- rMZ: Resemblance between MZ twins = 100% A + C
- rDZ: Resemblance between DZ twins = 50% A + C
According to Buss & Plomin (1984), what were the heritability findings for temperament traits?
- Emotionality: rMZ = 0.63, rDZ = 0.12, A ≈ 1.0
- Activity: rMZ = 0.62, rDZ = -0.13, A ≈ 0.98
- Sociability: rMZ = 0.53, rDZ = -0.03, A ≈ 1.0
What are the two main subtypes of antisocial behaviour (AB) in children?
- AB/CU+: Antisocial behaviour with Callous–Unemotional traits
- AB/CU−: Antisocial behaviour without CU traits
What characterizes Callous–Unemotional (CU) traits?
- Limited empathy
- Lack of guilt or remorse
- Shallow or deficient affect
- CU traits are used as a subtyping index in DSM-5 for conduct disorder.
Why is it important to differentiate AB/CU+ and AB/CU−?
The two subtypes likely have different genetic and environmental influences and respond to different treatment strategies, emphasizing the need for tailored interventions.
What is the definition of temperament according to Thomas & Chess (1977)?
“Temperament refers to the how of behavior, differing from ability (what/how well) and motivation (why). It describes the individual’s typical style of responding.”
What are the nine temperament traits in the Thomas & Chess Paediatric Approach?
- Activity level
- Regularity
- Approach–Withdrawal
- Adaptability
- Threshold of responsiveness
- Intensity of reaction
- Quality of mood
- Distractibility
- Attention span and persistence
What are Thomas & Chess’s three temperament types in their NY Longitudinal Study?
- Easy
- Difficult
- Slow-to-warm-up
How does the Personality Tradition define temperament? (Buss & Plomin, 1987)
Temperament is a set of inherited personality traits that appear during infancy. It is genetic in origin and observable early in life, distinguishing it from broader personality traits.
What are the three core EAS traits in Buss & Plomin’s model of temperament?
- Emotionality
- Activity
- Sociability
How do Rothbart & Bates (1998) define temperament in their Individual Differences approach?
Temperament consists of constitutionally based individual differences in emotional, motor, and attentional reactivity and self-regulation. These characteristics are stable and consistent across situations.
What are the main temperament traits in Rothbart & Bates’ model?
- Fearful distress/inhibition
- Irritable distress
- Attention span and persistence
- Activity level
- Positive affect/approach
- Rhythmicity
- Agreeableness/adaptability
What are the commonalities across different temperament theories?
- Temperament reflects individual differences, not norms.
- It comprises a set of traits, not a single one.
- Traits are biologically based and emerge early.
- Tendencies are consistent across contexts and relatively stable over time.
What are the key disagreements across temperament theories?
- Boundaries of temperament: What traits qualify
- Constituent traits: Which traits are central (e.g., emotionality vs. sociability)
- Relation to personality: When and how temperament transitions into personality
What is the evidence for heritability of temperament?
- The EAS traits (Emotionality, Activity, Sociability) show the strongest heritability.
- MZ twins consistently show higher resemblance than DZ twins.
- Overall, temperament is moderately heritable, with stability primarily genetic and change influenced by environment (Plomin et al., 1993).
How strongly is temperament influenced by genetic factors across the lifespan?
Temperament is moderately heritable, and this level of genetic influence is consistent across age groups.
What accounts for the stability and change in temperament over time?
- Stability is primarily due to genetic factors.
- Change from age to age is largely influenced by the environment (Plomin et al., 1993).
Is infant temperament more or less heritable than adult personality?
More heritable – Infant temperament shows stronger genetic influence compared to adult personality traits.
What is the historical significance of Thomas & Chess’s work on temperament?
- Challenged the “tabula rasa” (blank slate) view of child development.
- Emphasized temperament as an inborn trait.
- Introduced the concept of “goodness of fit.”
- Advocated for an interactionist and idiographic (individual-focused) clinical approach.
What is the “goodness of fit” concept in temperament theory?
A good fit occurs when a child’s temperament matches the demands and expectations of their environment, leading to adaptive functioning.
A poor fit occurs when there is a mismatch, leading to maladaptive behavior and developmental difficulties.
