The brainstem is comprised of the pons and medulla oblongata. It also contains the midbrain, which I’ll talk about in more detail on this page. This area of the brain contains many motor (movement) and sensory neurons which allow the transfer of information directly from the brain to the spinal cord. It controls the way the muscles move by sending information down the spinal cord to the appropriate muscle groups and it is also responsible for keeping you alive by coordinating the ANS.
The pons is located superiorly (above) the medulla and the brain stem and inferiorly (below) the midbrain and is connected to both the cerebral cortex (of the cerebrum) and the medulla oblongata (of the cerebellum). As a result of this, it serves two key roles: as a communications hub between the left and right hemispheres as well as the bridge between the brain and the spinal cord. It tends to serve several functions within the brain:
- It controls our sleeping patterns i.e. our diurnal rhythm
- It is responsible for making us feeling aroused whenever we see someone whom we consider attractive
- It takes care of our heartbeat and our breathing for us so we don’t have to worry about beating our hearts or taking a breath every few seconds
- It carries information between the cerebellum and cerebrum.
The medulla is located inferiorly (below) the pons and is anterior (in front of) the cerebellum. This is a red-hot zone for the control of autonomic movements, as it sends many messages down the brainstem. If you’ve eaten or drank something recently, your medulla would have been working. Also, by just standing or sitting wherever you are without even doing anything specific, your medulla would still be firing signals. How come? The medulla is responsible for these functions in your daily life:
- The digestion of your food is mainly coordinated by the medulla, as it works in two ways: it controls your sense of swallowing by controlling your epiglottis (the muscle between your oesophagus and trachea); it also sends signals to the smooth muscles in your GI tract to push food along
- It helps to contract your blood vessels and your heart (very important: especially if you’re doing exercise which requires more blood than if you’re just sitting down)
- It is also responsible for the sneezing reflex. If you’ve had a nasty cold, hay fever or the flu recently, you’ll probably be annoyed by this, but this reflex is a primary line of defence against germs and other contaminants entering the body: it shoots out particles at over 160km/h!
It is responsible for connecting the hindbrain and forebrain to one another and as the picture alongside shows, it consists of two structures, the tectum and the tegmentum. It performs several vital functions, such as:
- controlling our reaction to what we see
- the movement of our eyes as well as the dilation/contraction of their pupils based on the amount of light
- what we are able to hear
- how we move our bodies