Triple Science Only - The Brain

Higher Tier Only

Studying the Brain 

Neuroscientists are scientists who study the brain.

They can use several methods to map brain function:

1. Brain damage: Observing behavioural changes after injury to the brain. 

They can study people with brain damage to learn more about what different parts of the brain do.

A well-documented example of brain damage is of Phineas Gage, who in 1848 had a serious accident whilst laying railway tracks and an iron rod went through his skull.

Phineas survived the accident, but it was documented that his personality changed following it. 

It was noted that he lost his inhibitions socially and emotionally.

Doctors realised the changes in Phineas were due to the damage in the particular parts of the brain that the iron rod had passed through. 

This important case allowed scientists to examine the effect of the injuries on his brain activity.

2. Electrical stimulation: Stimulating parts of the brain and monitoring the effects.

The brain can be stimulated electrically by placing electrodes on the scalp or directly on the brain.

Scientists can stimulate different parts of the brain to see what the response is.

For example, if a region of the brain controlling movement is stimulated, a patient’s muscles will contract.

They can also use electrodes to monitor electrical activity in the brain, this can help to diagnose conditions like epilepsy.

3. MRI scans: Detailed imaging of brain structure and activity.

Neuroscientists can use MRI scans to monitor the electrical activity in the brain.

Scientists can use it to see which parts of the patient’s brain are active when they do different things, such as listen to music, recall a memory or look at images which provoke emotion.

MRI scans can also be used to look for abnormalities in the brain, such as swelling, tumours and any internal bleeding or blockages in blood flow

Patients must remain as still as possible during most MRI scans, as any movement can cause the images to become blurred and unreadable.

The brain is incredibly complex, and our limited knowledge means that treating brain damage and disease is very difficult!

Brain surgery has many risks- potentially damaging the brain tissue further and leading to lifelong impact on a person’s intelligence, memory, personality or movement.

Key Terms

• Cerebral cortex / Cerebrum - Outer layer of the brain that controls consciousness, memory, intelligence, and language.
• Medulla - Brain area that controls involuntary functions like breathing and heart rate.
• Cerebellum - Brain region that coordinates movement and balance.
• Hypothalamus - Part of the brain that regulates body temperature and helps maintain internal balance (homeostasis).
• Pituitary gland - The master endocrine gland – releases hormones that regulate many other glands in the body.
• MRI scan - A method used to produce detailed images of the brain to study structure and activity.

Exam Tip

Use labelled diagrams to revise so you are able to locate and label the key structures of the brain.

Describe how scientists have been able to map the functions of different areas of the brain. (3 marks)