I am grey in colour and made up of six layers. I cover the cerebrum and cerebellum as the outermost layer, but I am divided into two hemispheres. I am the place where all thoughts start and I am what makes Clare clever. I am Clare’s cerebral cortex and these are my thoughts.
When you look at a typical picture of a brain you’ll see me, I am the folded grey covering of that brain. I may look all wrinkled, but the reason I am like that is to increase my surface area. The bigger I am the more I can do! You’ll be amazed at just how much I can do, I play a very important role in Clare’s thoughts, memory, attention, language, perceptual awareness (being aware of surroundings), and consciousness.
Motor areas are important for voluntary movement, and found in both hemispheres of the brain. They are shaped like a pair of headphones, stretching from ear to ear. My primary motor cortex is responsible for making Clare make a movement i.e. taking a step forward, whilst the supplementary motor and premotor cortex play a role in selecting voluntary movements. The posterior parietal cortex guides voluntary movements in space, this is very important otherwise Clare would be throwing her arms and legs around all over the place. When Clare is learning to dance the dorsolateral prefrontal cortex decides which steps to take according to what Clare is thinking.
I am often referred to as grey matter. This is because I contain many cell bodies of the neurones (cells that make up the brain) that make up the brain, and capillaries. My six layers are very important, they comprise of different numbers and types of neurones. Together these layers interact to provide my basic functions.
It is common to hear me being described as comprising of three parts: sensory, motor and association areas. Sensory areas are very important as they receive and process information from the senses i.e. touch, pain, sounds, vision etc. Inputs from parts of the body travel along nerves to a little part of the brain called the thalamus which then sends the information on to me. If the input is a visual one then the message will go to my primary visual cortex to get processed. If it is an aural (sound) message it will go to my primary auditory cortex, and if it is a message regarding touch it will go to my primary somatosensory cortex to be processed. In general, my two hemispheres receive information from the opposite side of the body i.e. when Clare stands on a pin with her left foot, my right hemisphere will process the information.
The reason that Clare has learnt to speak English and can draw a cat on a piece of paper (not very well I might add!) is due to my association areas. These are important to make sense of the world and create meaningful perceptual experiences. They allow all humans to learn language and think abstractly by organising the sensory information that the brain receives. The lobes (parts of me) that are responsible for the organising of information are the parietal, temporal and occipital lobes. They take the information from Clare’s environment and centre it on her body image giving her a coherent perceptual model of herself and her world. The frontal lobe plays a role in abstract thought, but more importantly, it is involved in the planning of action and movement. My association areas are important to integrate the information coming into Clare’s brain from her senses, relate those to past experiences, then make a decision about what should be done, and then send a message to the motor areas of her brain so she can act.
It’s okay, you don’t have to say it....I’m pretty neat aren’t I! I bet you never knew that I even did half of that cool stuff. As you sit there reading this, just imagine what must be going on in your brain. I bet your cerebral cortex is having a busy time taking in all this information you have read, processing it and all whilst deciding what to have for lunch. So look after your brain, after all it’s what makes you, you.