Origins of criminal behavior
Biopsychologists
study bio aspects of behavior, try to determimne which genetic variables play part in criminal behavior, how important they are, and how to modify them. They don’t believe that genetics are sole or prim cause of human behavior
Genetics and Antisocial Behavior
- two methods of genetic research
Behavior Genetics
Dizygotic twins vs. Monzygotic
Twin studies
Shared environments
- % of antisocial
AKA common enviros include prenatal and life exps affecting twins in same way (twins raised by same bio parents)
Non-shared environments
Concordance rate
- first research
with %’s
The Twin’s Early Development Study
is one of most watched longitudinal twin studies conducted in United Kingdom on sample of twins born in 94,94, 96. Explores behavior problems and problematic development in lang, cognition, and academic abilities from childhood to adolescense
E-risk study
- males vs. females
Study with MZ and DZ twins in E-Risk study. Assessed antisocial behavior thru interviews and enviro risk by amount of maltreatment. Found that maltreatment on risk of antisocial development was strongest among those at high gentic risk (those who are predisposed to be antisocial more likely if maltreated)
-Evidence shows enviro affects fade as move into adulthood but genetic influence remains. This effect stronger in males, female aggression more influence by family enviro
TCHAD
• Twin Study of Child and Adolescent Development
Adoption studies
-Helps identify enviros most conductive to criminality
-Schulsinger Denmark Study: explored incidence of psychopahty in bio relatives of adopted adults. Compared 57 adopted psychopathic adults to 57 nonpsychopathic.
Found that 3.9% of bio relatives of psycho adoptess could also be psychopathic whereas only 1.4% of contorl groups bio relatives could (not stat signf)
Molecular Genetics
MAOA
MAOA-L (how many have?)
Psychophysiology
is study of dynamic interactions between behavior and autonomic nervous system
Temperament
Thomas & Chess perspective on temperament
-temp is innate readiness to respond to events that is evolving and influenced by family, parenting styles, and social environment. Temparment: has a constitutional bio basis, appears in infancy and continues thru life, and is influenced by enviro.
-Asked parents to report 9 characteristics of their infants and found
1. Easy child has high rythmicity, positive moods, high approachability, high adaptablility, and low intestity of mood expression
2. Diffictult child shows opposite; irreg bio functioning, initial aversion, slow adaptibility, high intensity of emotions, neg mood
3. Slow-to-warm-up child is high active, withdrawl from new stimuli, low adaptibility, neg mood and low intesnstiy
− Difficult children have cluster of inborn temperamental attribs that make child rearing difficult
−Most research on temp focuses on infant bc connection between it and behavior is uncomplicated at this stage and becomes more complex as child matures and interacts with enviro
Temperament indicators (2)
−Most experts agree that Activity and Emotionality are two of the behaviors that are strong indicators of temp
1. Activity is gross motor movement across various settings (move of arms, legs)
2. Emotionality is irritability, sensitivity, soothabiity, and general intensity of emotional reactions
−Self-regulation (degree of impulsivity) also included in temp
−Impulsive children move at higher pace against envroments and aggressive
−Girls seem temperamentally better than boys at self-reg
−Temp of parents must be considered as possible component of antisocial behavior development. Parents and offspring often resemble temps and personality
Environmental risk factors
-In utero exps play role in predisoposition to criminal behavior. During preg, fetus exposed to influences that can adversly affect development (exposure to a toxic or diseased enviro)
Ex: fetus’s exposed to drugs at high risk for conduct probs 10-13 yrs later as are fetu’s exposed to pot, alcohol, and cigs
-Fetal alcohol spectrum disorder (FASD) is a serious med condiction resulting from alcohol exposure prenatally. Youth with FASD linked to high rate of self reg probs, antisocial behavior; have low level of serotonin
-Exposure to lead another example; leads to cog problems
Birth complications
Nicotine, Alcohol and Drug Exposure
Brain development
-Limbic system, a group of connected brain structures and circuits that is a component of impulsive violence
Brain plasticity