Steven Crane Compiled Section Handouts. Human Behavioral Biology 2012

Rwandan genocide with intermixed Tutsis and Hutus.

Summer camps with Palestinian and Israeli kids: have the same prejudices but have complex rationalizations on how the kids they know are different from the rest. So it takes more contact than one summer.

What else about early life environment might bias an individual towards a life of crime/aggression?

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  Being born unwanted.
  
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    Leavitt and Donohue found that 50% of the variance in the drop in crime in the 1990's could be attributable to Roe v. Wade. Idea being that fewer "unwanted" children were born, and thus fewer crimes in adulthood.
    
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  Stress/poverty in childhood makes for a thinner frontal cortex with a lower resting metabolic rate leading to
  

worse performance on executive function tasks.

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  Witnessing violence in childhood
  

What important control-related brain region is developing during adolescence?

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  The frontal cortex is still myelinating up to age 25.
  
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  Supreme Court intelligently and stupidly made a cut-off that people under age 17 can't be executed for their crimes, but the morning of your 18th birthday you suddenly can be. Breaking a continuum into buckets!
  
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  Also dopamine rewards fluctuate a lot more wildly in adolescence than in adulthood.
  

How does perinatal hormone exposure influence aggression?

What is fetal androgenization? How does/did it happen?

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  When female fetuses are exposed to high levels of androgens (like testosterone) during perinatal life.
  
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  Happens in cases of congenital adrenal hyperplasia (CAH) where adrenal glands pump out a lot of androgens, and also in cases of exposure to diethylstilbesterol (DES).
  

What were the results in terms of aggression?

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  Overall, nothing very meaningful in the way it was initially interpreted. Originally interpreted as "more aggressive" but that turned out to mean "interested in careers" and "less interested in dolls" than "normal" girls.
  

What were the results for other traits?

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  Higher IQ, though not when controlled with siblings.
  
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  Better spatial skills, higher rates of left-handedness, lower empathy and intimacy, potentially more aggressive behavior. All of these are solid findings. But what's a big confound?
  
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    Huge confound: born with ambiguous genitalia which takes a lot of reconstructive surgery and distress, and also probably treated differently from non-androgenized girls.
    

What is the theory of autism as a hyper-male profile?

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  Autistic people have an exaggeration of traits that are male-typical patterns:
  
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    Better spatial skills
    
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    More systematic-based strategies for problem solving (as opposed to empathy-based approaches)
    
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    Worse verbal skills
    
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    Worse social cue reading
    
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    Worse theory of mind
    
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    Lower tendency to read facial expressions by looking in the eyes
    
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    Thinner corpus callosum
    
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  All of these with slight differences in the average and large overlap!! So autism might have something to do with prenatal androgenization.