Biological Explanations Of Offending Flashcards
Atavistic form theory
The earliest theory to explain offending behaviour came from Lombroso in 1870. He believed that criminals had distinguishing physical features, which originated from a more primitive stage of development and these features were said to be atavistic.
Lombroso Study - atavistic form
Measured the physical features of Italian criminals. The sample contained almost 4000 living criminals and the skulls of 400 dead criminals who were all male
Examples found included heavy brow, large, strong jaw, high cheekbones, extra nipples, extra fingers/toes
He also suggested that different types of criminal have different features such as sex offenders having thicker lips
43% had at least 5 atavistic traits
EVALUATION- Lombroso atavistic form theory
Strength - support his theory with research - explain research - objective and factua - however no control group and physical features may be coincidental
Goring attempted to replicate findings by comparing a large group of offenders with a control of non criminals but found no significant differences between the two - therefore atavism may not be linked to offending - may be interaction of physical features and environment eg due to treatment
Kaplan self derogation theory argues if others experience persistently poor interactions they will develop low self esteem and increased frustration making them more likely to commit criminal behaviour - environmental factors predominant cause - however implications of it being socially sensitive
Genetic explanations to offending - chromosomes
People who are born with an extra Y chromosome have a predisposition to offending due to increased testosterone. Increased testosterone levels have been found it be correlated with increased aggressive behaviour in males with 47 XYY syndrome
Genetic explanations - what can the XYY chromosome cause
Emotional immaturity
Poor socialisation
Instability
Extreme aggressiveness
Low IQ
EVALUATION of the genetic explanation to offending
STRENGTH - research support - Lange investigated 13 MZ twins and 17 DZ twins. 10 of MZ twins and only 2 of DZ twins had a co twin in prison - supports as higher concordance rate between MZ twins who share 100% of same genes - however confounding variables as grew up in the same environment
STRENGTH - further research support - Mednick et al conducted study of 13,000 danish adoptees. no criminal record for adopted or biological parents, adoptees that did = 13.5%, 20% when either biological or adopted parent and 24.5% when both had convictions - supports as percentage increased when biologically related suggesting inherited criminal trait - however increases even further for both parents suggesting mix of biology and environment
WEAKNESS - research to show the impact of the environment- Farrington longitudinal study 411 boys from ages 8-48. by 48 161 had convictions and found common characteristics among ‘persisters’ who offended before and after 21st bday such as poverty,poor child rearing, poor school performance showing impact of the environment - however there was history of family criminality also showing role of genetics with a positive correlation between convicted parent and persisters
Neural explanations of offending - neurophysiological - Raines study
Quasi experiment using PET scans to analyse the brains of convicted criminals. Matched pairs on age, gender schizophrenia.
41 murderers who pleaded NGRI (not
guilty by reason of insanity). Control group of 41 non-murders - Only 2 females. PET scan to study the brain areas.
Results – asymmetrical activity in the amygdala (lower in one hemisphere than the other), lack of activity in the
thalamus and other areas of the limbic system. Lack of activity in the PFC
Outline and Describe three key brain areas for criminal behaviour summary- neurophysiological explanation
• Limbic System: emotional regulation and regulation of hormones. Reinforcing the use of aggression, dopamine kick or high.
• Amygdala (in limbic system) – fear response, recognising fear in others – high levels of dopamine (confuses fear for aggression).
• Pre Frontal cortex – involved in consequential thinking, more activity within this area. – involved in high impulsivity
NEUROPHYSIOLOGICAL - evaluation
STRENGTH - further evidence to support - Raine examined 71 brain imaging studies and found murderers, psychopaths, and violent individuals have reduced functioning in the prefrontal cortex - supports as pre frontal cortex is responsible for impulse control and decision making so if underactive they may struggle with controlling aggressive impulses - however can not explain the motivation behind non aggressive crimes like fraud
WEAKNESS - the link between brain abnormalities and later criminality is spurious - research only highlights a correlation between brain abnormality and offending - this does not imply causation and it can not be studies in an experimental way as it is unethical - raises ethical concerns of how people with brain abnormalities should be treated
Neurochemical explanations of offending behaviour - SEROTONIN
Low levels of serotonin are linked to a lack of decision making and being more impulsive
Neurochemical explanations of offending behaviour - DOPAMINE
High levels of dopamine in the limbic system reinforces aggression and rewards feeling and desire to repeat certain behaviours
Neurochemical explanations of offending behaviour- NORADRENALINE
High levels = increased use of sympathetic pathway of fight and flight - overactive SAM system
Low levels = reduces ability to perceive threats - perceiving things in the environment as threats which are not increasing criminality due to fearfulness
NEUROCHEMICAL evaluation
STRENGTH - research support - Scerbo and Raine conducted meta analysis of 29 pieces of research into anti social adults and children and found in all cases low serotonin - supports as it leads to impulsivity and problems with decision making hence criminality implying offending behaviour is biological eg mutation in MAOA - L producing low serotonin- however research is correlational and reductionist as low levels of serotonin may be caused by environment ed poverty lack of job stressors
CRITICISM - Impossibkr to delegate neuro chemistry from environmental factors - eg reason for an offenders change in neuro chemistry could be she to abuse or trauma in childhood resulting in disorganised attachment therefore changing how the genes express themselves (epigenetics) - if believed offending was biologically caused then implies criminals have no free will and problems with responsibility, eugenics of identifying if babies will be criminals
