Biology

Brain Dysfunction

It could be that some people have more understanding and empathy qualities than others due to the physical nature of their brain.

Look at the curious story of Phineas Gage (Harlow, 1848)

• He was a railroad worker
• Well adjusted individual
• Efficient worker
• An iron bar was driven through his skull during an accident
• The bar went straight through his head 
• His brain was damaged
• His intellect was not affected by the accident
• Personality was transformed
• Became aggressive
• Lacked patience
• Gage’s skull was examined after his death
• Sustained damage to the pre-frontal cortex
• Pre-frontal cortex plays an important role in moral decision making

Professor Adrian Raine carries out research on the brain at the University of Southern California. He employs a PET scanner to find out which areas of the brain are being used.

Raine et al (1997) carried out a study on brain dysfunction in criminals using a PET scanner. Using a group who had been charged with murder but had used the defence of insanity. Some had mental illnesses such as schizophrenia, some had brain injuries and others personality disorders. There was also a control group that did consist of schizophrenics but they hadn’t been in trouble with the law. Raine wanted to examine what was going on in their brains when they completed a task and what differences there were between these two groups.

The brain below, indicate Raine’s results of the experimental group

Image

Raine also discovered that the experimental group had more activity on the right side of the amygdale (controls emotion, regulates sleep) and also the hippocampus (plays an important role in memory and spatial navigation)than on the left. This could demonstrate individuals involved in violent crime to experience a lack of fear.

Unsurprisingly, Raine concludes there is a link between the structure of the brain and criminal/violent behaviour. However, Raine emphasises that this evidence may only suggest a predisposition to violent behaviour. After all, we cannot know for sure if the brains are like this as a result of committing a crime and the trauma of being placed in prison. Additionally, to place too much emphasis on such results would be quite deterministic, suggesting that an individual has no control over their actions.

What could be a major implication from such a study as this?

Violent criminals could use as a defence that they couldn’t help what they did because they have abnormal brains! This would suggest that violence is determined by biology alone

A further study of Raine’s (2002) was to comprehend the development of antisocial behaviour in children.

GOAL; To create a multi factor approach to comprehending aggressive behaviour in children

METHOD; A meta analysis of many articles on neurological and neuropsychological studies

RESULTS;  Activity in the pre-frontal lobes of reckless children who are likely to be antisocial later is lower

Young people who may have an intrepid disposition also tend to have a low resting heart rate and may seek excitement

The young brain doesn’t finish developing until early twenties

Risks of a young person becoming antisocial and aggressive are poor parenting, physical abuse, and smoking during pregnancy and birth complications

CONCLUSION; To reverse biological shortfalls that may predispose antisocial and aggressive behaviour is to encourage early intervention and prevention

Genes and Serotonin

Genes instruct the body how to grow and develop. Genes can affect your height, weight, your eye and hair colour and maybe your personality too.

The sixty four million dollar question...Do you think there is a gene for criminality?

There can’t be a gene for criminality as criminality depends on the culture in which you live. Different cultures have different ideas as to what constitutes right from wrong and your genes would be unable to recognise this. However, genes may give a person a predisposition to break the law and behave in a criminal way; this is a tendency that is innate and means the person may develop in a certain way. Therefore, some people may have a predisposition to be angry and aggressive and take certain risks. Though this doesn’t necessarily mean they will become criminals. It also depends upon the environment in which they live.

Studies with twins can inform us about about genetics and crime. If twins have been brought up apart and still turn out the same, biology can be the only cause for their behaviour (though many would say the environmental still plays a role).

• Monozygotic Twins (MZ) are physically identical and have exactly the same genes
• Dizygotic Twins (DZ) may look similar but are just like brothers and sisters and aren’t genetically alike like MZ

Christiansen (1977) investigated 3586 twin pairs in Denmark and a 52% concordance rate for criminality was found for monozygotic twins compared to just 22% for dizygotic twins.  It is, however, necessary to take into considered the influence of a shared upbringing. This study is particularly reductionist. If crime really was wholly genetic then a 100% concordance rate for monozygotic twins as they share 100% of their genes would the expected result.

Serotonin is a hormone and is a neurotransmitter. It assists with nerve impulses travelling from one region of the brain to the other. Serotonin orders our moods and fights off depression. You may have heard of SSRI (Selective Serotonin Reuptake Inhibitors) antidepressant drugs which help increase the level of serotonin to ward off low mood.

Higley’s (2000) work with rhesus monkeys and serotonin canbe seen below.

Gender

According to National Statistics men commit crime four times more often than women.

It could be due to upbringing and boys being encouraged to be more aggressive or due to social bonds whereby women care for families more.

Evolutionary biologists say men have risk taking and impulsive traits in order to survive. History says that risk taking men get the girl and survive.

Wilson and Daly (2001) conducted a correlational study into homicide rates and life expectancy in Chicago and life expectancy was found to be a good predictor of homicidal rates. Young men require immediate fulfilment and they don’t look to the future. Therefore they take risks to gain instant reward. Truancy from school was additionally negatively correlated with life expectancy.

The conclusions from this study were that young men from poor backgrounds tend to involve themselves in risky behaviour and expect to live shorter lives.

Below are 5 other reasons that could account for these findings other than life expectancy

• Poverty
• Upbringing
• Personality predisposition
• Inequality
• Life events