MRI image of a brain showing an astrocytoma

Brains to blame

New techniques and developments in brain imaging can raise tricky ethical questions

Brain injuries often affect a person’s behaviour and personality, causing them to do things that they may not otherwise do. One example is the US schoolteacher who began visiting prostitutes and collecting child pornography, then molested his 12-year-old stepdaughter. The man was eventually charged and remanded in custody.

He then started complaining of severe headaches, which got so bad that he was taken to hospital. A brain scan showed that he had a large tumour in his frontal lobe. Doctors removed the tumour and his inappropriate sexual behaviour stopped. But about a year later, the tumour grew back, and the behaviour returned.

Drug treatments can also cause profound changes in behaviour. The drug L-dopa, for instance, which is given to patients with Parkinson’s disease, can sometimes lead to compulsive gambling or impulsive sexual behaviour.

Questions for discussion

  • Are people responsible for their actions in cases like this?
  • Should they be punished in the same way as others, or should their brain damage or drug treatment be taken into account?
  • And is there an ethical problem with prescribing a drug when it is known to have side-effects, like L-dopa?
  • According to research published last year, judges are more lenient towards violent criminals who are known to be genetically predisposed towards violence. Do you think this is right? ​

Lead image:

MRI image of an astrocytoma in a young child. Astrocytomas are tumours that grow from a type of brain cell called an astrocyte, which is the most abundant cell in the brain. Around one-third of all brain tumours in the UK are astrocytomas. MRI scans are often used to diagnose brain tumours and help locate tumours so they can be accurately removed in surgery. 

Wellcome Collection CC BY


Further reading

About this resource

This resource was first published in ‘Inside the Brain’ in January 2013 and reviewed and updated in November 2017.

Neuroscience, Psychology
Inside the Brain
Education levels:
16–19, Continuing professional development