Our brain is our control centre - all our actions, thoughts, emotions, and personality are controlled by it. That's a pretty amazing feat for something roughly the size of a small cauliflower! The brain is part of our central nervous system (CNS); the rest of the nervous system includes the brain stem, spinal cord and all of our nerves.
It is a bit complicated, but understanding more about the brain can help with understanding about brain tumours.
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different parts of the brain
The brain is contained within the skull. It is surrounded by three thin membranes or layers called the meninges, between two of these layers there is fluid called cerebrospinal fluid (CSF). These layers surround the brain, the brain stem and the spinal cord. They protect them, acting as a cushion. The brain is made up of three main areas:
- Cerebrum - This is the biggest part of the brain and is made up of two halves – the left and right hemispheres. The right hemisphere controls the left side of the body and the left hemisphere controls the right side of the body. Although they are two halves they are connected and messages are sent between the two hemispheres.
- Cerebellum - This is at the back tucked underneath the cerebrum.
- The brain stem - This is the bottom part of the brain and connects the cerebral hemispheres to the spinal cord.
what does each part do?
Each cerebrum has four lobes:
- The frontal lobe - This is at the front of the brain. It contains areas that control your personality, thought, memory and behaviour. Towards the back of the frontal lobe are areas that control movement and feeling. Our sense of smell is also controlled here.
- Parietal lobe - This is just behind the frontal lobe and deals with sensations like touch, pain and temperature.
- Temporal lobe - This is underneath the frontal lobe just above your ear. It helps us recognise sounds, speech and memory.
- Occipital lobe - This is at the back of the cerebrum and deals with how we work out what we are seeing.
Between the two hemispheres just above the cerebellum are the thalamus and the hypothalamus. The thalamus controls where in the brain information goes to be interpreted and the hyopothalamus deals with things like body temperature, hunger and thirst, and the hormones associated with fertility and maturity.
cerebellum
This is responsible for our balance and co-ordination. These activities are carried out automatically (we don’t have to think about them) by this area of the brain.
the brain stem
This is our life support control and responsible for body functions, including blood pressure, breathing, heart beat, eye movements and swallowing.
The brain is a very complicated organ and quite amazing. Like the rest of the body it is made up of cells. There are different types of cells in the brain including nerve cells called neurons. There are around 40 billion neurons - these cells conduct the nerve impulses which are behind every brain function. We are all born with these cells. One of the differences between nerve cells and other cells in the body is that they can’t reproduce and when they are worn out they can’t produce more so the number of cells in the brain gradually decreases as we get older! There are a trillion connections, called dendrites, linking the brain's neurons, which adds up to more connections around the brain than there are stars in the entire universe.
To keep all of these nerve cells in place there are different types of cells called supportive cells or glial cells. The different types of glial cells are: astrocytes, oligodendrocytes and ependymal cells. These all have the ability to replace or reproduce themselves if they need to.
