Transcript
SPEAKER
This is a human brain. It looks rather like a walnut, with ridges and grooves. The outer layer, containing these ridges and grooves, is known as the cortex.
The pattern of ridges and grooves is not haphazard. It’s broadly similar from one person to another, forming a kind of map of the outer part of the brain. The outer part of the brain is divided into a series of lobes.
This is the frontal lobe, the part of the brain which is largely responsible for reasoning, movement and language. A subdivision of the frontal lobe, known as the prefrontal cortex, is important for executive function. This includes planning complex behaviour, decision-making and moderating behaviour. The orbitofrontal cortex is a subregion of the prefrontal cortex and is situated at the very front of the brain. It is involved in reward and emotions. This is the parietal lobe. It is involved in processing touch information and spatial awareness. This is the occipital lobe. It is involved in the processing of visual information. The temporal lobe, or as it is sometimes called, the temporal cortex, is important for memory, hearing, and understanding speech.
From the front, you can see that much of the brain is divided down the middle. It appears symmetrical about its midline. The two halves of the brain are known as hemispheres. There is a right and left hemisphere, defined not from your perspective, but from the perspective of the person whose brain it is. So the right hemisphere of this brain is to your left.
The lower part of the brain is known as the brain stem. It is responsible for basic bodily functions, such as breathing, control of heart rate, control of blood pressure and consciousness. From this angle, you can also see the pituitary gland. This releases certain types of hormones into the blood and responds to signals from the brain. Part of the brain has a distinctly different external appearance. This is the cerebellum, and it is important for the control of movement.
There is a rich supply of blood vessels that carry blood to and from the brain, bringing nutrients and oxygen to cells of the brain and carrying away waste products for disposal. A constant blood supply is vital for the cells of the brain to perform their function.
This is a slice through the brain. It is called a coronal cut and slices the brain into a front and back portion. The different colours arise from differences in the cells present. The cortex, the outer region, has a darker appearance than the inner region. The darker region is called grey matter, although it is pinkish in reality. The lighter region is called white matter.