Turning to crime Biology

Turning To CrimeBiology Brain Dysfunction Raine Genes and Serotonin BrunnerGender Daly & Wilson

Biology A third influence that may affect an individual’s likelihood of turning to crime is biology. When considering this influence we would include genes, hormones, neurology and gender. So far, a complete biological explanation is not good enough, but the interaction of some biological predispositions with environmental influences can explain the individual differences we see where only some ‘at risk’ individuals take the step into criminal behaviour. For example: Genetic variation MAY be responsible for causing differences in an individual’s level of aggression which may lead to violent crime. However it is unlikely we can biologically explain crimes such as; fraud, theft, drug-dealing etc. Cases have been reported whereby a brain tumour has changed the personality of an individual from a well-behaved caring person to a violent and uncontrolled individual.

Biological: Brain Dysfunction Adrian Raine conducted research using PET scanning and found abnormalities in some parts of the brain in violent criminals. He has found that low physiological arousal, birth complications, fearlessness and increased body size are early markers for later aggressive behaviour. His explanation is considered to be a Bio psychosocial explanation.

Put your thinking caps on! Prefrontal cortex Amygdala Hippocampus Cerebellum Thalamus Learning & memory Mental disorders Emotions Memory & thinking Learning & memory

Earlier work by Raine and others had demonstrated the relationship between low levels of activity in the prefrontal cortex and violent behaviour (Raine 1994). This is an area of the brain behind the forehead and Raine describes the function of this part of the brain as like ‘the emergency break on behaviour’, which prevents us from acting on violent or aggressive impulses. It is thought that the prefrontal cortex sends messages to the limbic system to tell us to fear the consequences of acting on our impulses. The limbic system is part of the old brain which governs our emotional and aggressive impulses. The hippocampus (remember Maguire) and amygdale are key structures in the limbic system. Raine suggests that violent offenders have shown abnormalities in these areas in the function of the different hemispheres (remember Sperry) and developments of brain imaging techniques have allowed research to be carried out into the possible brain dysfunction in violent offenders.

Evaluating Raine’s evidence for explanations into criminal behaviour Raine’s more recent work has led him to believe that biological predispositions are ‘switched on’ by environmental conditions. If these environmental conditions do not exist, then the child is much less likely to turn towards crime. What does this suggest about crime prevention? A major concern about all biological explanations is the labelling effect. Why is this important in relation to ethics and what can this effect lead to within individuals? What types of crime can’t be explained by this theory?

Biology: Genes and Serotonin Genetic explanations of criminal behaviour have ranged from the “XYY Theory” of the 1960s to the twin studies of the 1970s. – it was proposed that males with an extra Y chromosome (males should have one X and one Y chromosome) were predisposed to be violent criminals (Price et al., 1966). This genetic abnormality became known as 'the supermale syndrome'; individuals who had it were above average height and below average intelligence. The XYY theory offered the prospect. The XYY theory offered the prospect of a genetic explanation, which carried with it the weight of scientific knowledge and potentially offered possibilities of screening people before they had committed a crime, cutting the risk to the population at a stroke. However, later research failed to find more than low correlational support for the original findings. The over-representation of XYY individuals in prison populations may have had more to do with their lower intelligence, making them more likely to get caught and to have suffered poor educational performance, which in itself is a risk factor for becoming criminal. Turning to crime

Biology: Genes and Serotonin Researchers have searched for genetic explanations for criminality by looking at how crime runs in families. The most common way to do this is to work with identical twins. Christiansen (1977) found a 52% concordance rate for criminality in MONOZYGOTIC twins and 22% in DIZYGOTIC - but this study was fraught with reliability issues. However, we must remember the effects of shared upbringing and if crime really was genetic we would expect a 100% concordance rate for monozygotic twins as they share 100% of their genes. A totally biological explanation would be seen as reductionist; an advantage of this being that it can give an understanding of the cause of behaviour, but is missing out on the complexity of human nature.

Biology: Genes and Serotonin Further research suggests that Monoamine oxidase (MAO) is an enzyme in the mytochondria (the powerhouses found in large numbers in every cell that provide the cell with energy). MAO is the enzyme responsible for breaking down several neurotransmitters (brain chemicals which relay, amplify, and modulate signals between a neuron and another cell) including monamines: serotonin, dopamine and norepinephrine.chemicalsneuroncell Therefore it also has an effect on the levels of these neurotransmitters in the body. There are actually two MAO enzymes, MAOA and MAOB, and they are produced by two different genes that have loci (or “addresses”) close to each other on the short end of the X chromosome. This means that these genes are sex-linked. It is well known medically that inhibiting the production of MAO, particularly MAOA, using drugs is a very effective way of treating depression. So, by inference, it would seem that altering MAO enzymic activity can affect the brain by altering its chemistry.

Biology: Gender The final study concerning biology (and turning to crime – woop!) is an evolutionary explanation for human behaviour. This assumes that behaviour has an adaptive quality which means it is more likely that it will be passed on biologically as it is a quality that will aid survival. Turning to crime

Introduction to the world of Evolutionary Psychology Read the section on Gender on page How do evolutionists explain risk-taking behaviour in males?