ASPD ASPD Neurobiological and Genetic Factors 1 — Questions and Answers
Question 1: Which brain region is most consistently implicated in the reduced emotional processing seen in individuals with ASPD?
- Amygdala (Correct answer)
- Hippocampus
- Cerebellum
- Thalamus
Correct answer: Amygdala
The amygdala shows reduced volume and activity in individuals with ASPD, contributing to deficits in fear conditioning and emotional empathy.
Question 2: Twin studies on antisocial behavior in ASPD suggest that heritability accounts for approximately what percentage of variance?
- 10-20%
- 40-60% (Correct answer)
- 80-90%
- Less than 5%
Correct answer: 40-60%
Twin studies consistently estimate that genetic factors account for roughly 40–60% of the variance in antisocial behavior associated with ASPD.
Question 3: Which neurotransmitter system is most strongly associated with impulsivity and aggression in ASPD?
- Dopamine
- Serotonin (Correct answer)
- GABA
- Acetylcholine
Correct answer: Serotonin
Low serotonin activity is strongly linked to impulsive aggression and poor behavioral inhibition characteristic of ASPD.
Question 4: What does neuroimaging research consistently show about prefrontal cortex volume in individuals diagnosed with ASPD?
- Increased gray matter volume
- Reduced gray matter volume (Correct answer)
- Normal volume with hyperactivity
- Enlarged white matter tracts
Correct answer: Reduced gray matter volume
Studies demonstrate significantly reduced prefrontal cortex gray matter in ASPD, which is associated with impaired decision-making and impulse control.
Question 5: The 'callous-unemotional' trait in youth that predicts adult ASPD is most closely linked to dysfunction in which biological system?
- Hypothalamic-pituitary-adrenal (HPA) axis
- Mirror neuron and empathy circuits (Correct answer)
- Digestive microbiome
- Visual cortex pathways
Correct answer: Mirror neuron and empathy circuits
Callous-unemotional traits are linked to reduced responsivity in the mirror neuron system and empathy-related circuits, particularly the amygdala–ventromedial prefrontal loop.
Question 6: Which gene variant has been most studied in relation to aggressive antisocial behavior in ASPD research?
- BRCA1
- MAOA (monoamine oxidase A) (Correct answer)
- ApoE4
- HTT (serotonin transporter)
Correct answer: MAOA (monoamine oxidase A)
The low-activity variant of the MAOA gene ('warrior gene') has been extensively studied as a genetic risk factor for aggression and antisocial behavior, especially when combined with childhood maltreatment.
ASPD ASPD Neurobiological and Genetic Factors 1
Which brain region is most consistently implicated in the reduced emotional processing seen in individuals with ASPD?