5.8 Brain Flashcards
What is the brain made up of?
Billions of interconnected nerve cells
What is the cerebral cortex?
The outer wrinkly bit. Responsible for things like consciousness, intelligence, memory and language as well as the senses like vision and hearing.
What are the two sides of the cerebral cortex called?
Hemispheres
What side of the body does the left side of our cerebral cortex control?
Right
What side of the body does the right side of the cerebral cortex control?
Left
What is the cerebellum responsible for?
Conscious movement like balance and muscle coordination
What is the hypothalamus responsible for?
Regulating body temperature and sending signals to the pituitary gland
What does the medulla in the brain stem do?
Controls unconscious activities like breathing and your heartbeat
Explain the three different ways that scientists are able to study the brain
1) Studying patients with brain damage - If a small part of the brain has been damaged, the effect this has on the patient can tell you a lot about what the damaged part of the brain does. E.g. if an area at the back of the brain has been damaged by a stroke and the patient went blind, you know that that area has something to do with vision. However, if a person is severely brain damaged, it may be unethical to study them as they might not be able to give informed consent.
2) Electrically stimulating the brain - The brain can be stimulated electrically by pushing a tiny electrode into the tissue and giving it a small zap of electricity. By observing what stimulating different parts of the brain does, it’s possible to get an idea of what those parts do. E.g. when a certain part of the brain (known as the motor area) is stimulated, it causes muscle contraction and movement.
3) fMRI scans - Functional magnetic resonance imaging (fMRI) scanners are big tube-like machines that can be used to show which parts of the brain are activated when performing certain tasks inside the scanner (like listening to music or trying to recall a memory). Also, CT-scans that use X-rays can be used and PET scans that use radioactive chemicals can be used.
Describe why treating problems in the brain can be tricky (3)
Many things can go wrong with the brain or other parts of the nervous system, e.g. injuries to the brain or spinal cord, tumours, diseases etc. These can be difficult to treat successfully.
- If a problem occurs in a part of the nervous system that’s not easy to access it can be hard to treat, e.g. it’s not possible to surgically remove tumours growing in certain parts of the brain.
- Treatment for problems in the nervous system may lead to permanent damage, e.g. surgery to remove a brain tumour may leave surrounding parts of the brain permanently damaged.
- It’s hard to repair damage to the nervous system. Neurones don’t really repair themselves because, once they’ve differentiated, they don’t undergo mitosis. This means they can’t divide to replace lost neurones. Scientists are investigating the use of stem cells to replace damaged tissue in the nervous system - but there are ethical issues surrounding stem cell use.
What are CT scans mainly used for?
Seeing which areas of the brain are damaged
What are PET and MRI scans used for?
Measuring the underlying activity of the brain
When we view images of the brain we are generally looking at a cross section of the brain. What is a cross section?
A view into the inside of something made by cutting it.
Where in the brain is the medulla found?
In the brain stem
