Understanding the Brain
Higher Tier Only
- Our understanding of brain structure and function is limited for several reasons
- The brain is incredibly complex and very delicate
- Different regions can’t be studied in isolation
- Consequently, it is extremely difficult for neuroscientists to study it to find out how the brain works
- Specialised scanners can be used to study the brain without having to resort to surgical intervention
CT scanners (Computerised Tomography)
- CT scans produce 3D images of the brain using X-rays which are fired at the brain from multiple different directions
- A scan produced in this way shows physical structures of the brain and allows visualisation of any tissue damage
- The scans don't directly show the functions of the regions of the brain, however, symptoms caused by tissue damage can allow neurologists to work out which regions of the brain are responsible for which functions
- CT scans are not recommended for pregnant patients or children due to the risks of exposure to the X-ray radiation, which is given at a higher level than in a normal X-ray
PET scanners (Positron Emission Tomography)
- PET scans use radioactive tracers which collect in areas where there is an increased blood flow
- This includes the active regions within the brain as well as cancerous tissues which have a higher blood flow than healthy tissues
- The tracer is introduced to the blood in advance of the scan so that it can be detected by the scanner
- Neurologists can use the images to study the structure and function of the brain in real time
- This has been useful in building understanding of specific diseases such as Parkinson's
Treating damage and disease to the CNS
- Our limited understanding means that treating damage and disease in the CNS is very difficult for many reasons
- Cancerous tumours can be located deep into the brain or spinal cord and so cannot be surgically removed at all from some regions
- Tissues of the nervous system don't repair in the same way that other tissues do
- We do not know exactly which regions of the brain are responsible for which functions
- Due to the delicate nature of nerve tissue, any potential treatment carries risks of further damage occurring which can lead to increased problems
- Accidental damage could lead to speech or motor issues, or changes to personality which are permanent
