Last week we took a look at the different organ systems. This week we will be looking at the nervous system in greater detail. Let’s begin!
The nervous system allows the body to react to changes in our internal and external environments. It controls the functions of our body such as circulation and respiration.
We can divide the nervous system into different parts. There are the central nervous, peripheral, autonomic, and somatic nervous systems. This week we will look at the central nervous system, commonly termed the CNS.
The central nervous system consists of our brain and spinal cord. But what kind of cells are present here?
We have neurons! More specifically multipolar motor neurons and psuedounipolar sensory neurons. Neurons are the functional unit of the CNS. They allow for fast communication within the central nervous system. What makes these cells unique to the central nervous system is that a myelin sheath surrounds them. This increases the velocity of nervous impulses. Neurons are covered by a different substance in the peripheral nervous system (more about that next week).
The central nervous system integrates and coordinates incoming and outgoing neural signals and carries out higher mental functions such as learning and thinking.
The brain and spinal cord are composed of grey and white matter and three layers of meninges surround them. The cranial and spinal meninges are continues with each other. Let’s take a look at the different meninges:
Dura mater - This in Latin means ‘tough mother’, it is the strongest meninges and outermost layer and attaches to the inner skull.
Arachnoid mater - This web-like layer is where you can find cerebrospinal fluid(CSF). This fluid acts as a shock absorber.
Pia mater - This weak, thin membranous layer is the innermost meninges and can be found on the brain's surface. It is home to the blood vessels supplying the CNS.
Now let's take a closer look at the brain:
The brain has two cerebral hemispheres, with the same lobes on each side. Each lobe is responsible for different functions.
The frontal lobe is what makes you, you!
The parietal lobe is involved in language processing.
The temporal lobe is for processing auditory information(hearing).
The occipital lobe is for vision.
The cerebellum helps coordinate movement and regulate temperature.
The brain stem is the most important structure in our body. It is in charge of breathing, blood pressure, heart rate, and sleep. You can understand why it is so important!
The spinal cord carries nerve signals from your brain to your body and back again! The central nervous system is essential for life.
Next week we will take a look at the peripheral nervous system.
Get your tickets to the UK's only live post mortem experience, click here!