And we’re back with The Brain series pt. 3!
Starting off, let’s talk about ventricles and cerebrospinal fluid. Deep inside our brain, there are cavities called ventricles that are filled with fluid. Inside these cavities is the choroid plexus that produces cerebrospinal fluid (CSF), which is in and around the brain and spinal cord to act as a safeguard, in case you injure your head or get in an accident. The fluid follows a cycle of absorption and replenishing by the plexus. Two main ventricles located in the left and right hemispheres are referred to as the lateral ventricle. These cavities connect to the third main ventricle at a location called the “foramen of Monro”. The third ventricle meets the fourth at the “aqueduct of Sylvius”. This system of CSF is delicate, and any interruption or obstacle in the system can cause the ventricles to swell up or the CSF to pool together in the spinal cord, neither of which is good news.
Now, let’s move onto the skull. Why do we have it? Well, the main reason is that it acts as a helmet for our brains. It’s made up of eight fused- together bones that create three main areas: anterior fossa, middle fossa, and posterior fossa. If we hit our head or get into an accident, the skull is able to cushion the blow and absorb some of the shock– helping to prevent injury.
And our final topic of the week: cranial nerves. These begin at the brainstem and leave the skull through the foramina, which are small holes in the skull. The brainstem itself leaves through a bigger hole called the foramen magnum. These foramina are the only exit path for all arteries, nerves, and veins that have to leave the skull. Going back to cranial nerves, what do they do? Their job is to send messages along to parts of the body from the brain. There are twelve pairs in total, and ten of them control hearing, eye movement, the sensation of touch on our faces, eating, and facial, neck, and shoulder muscles, while the other two are in charge of smell and vision.
Stay tuned for next week, pt. 4 of The Brain series! We’ll be discussing Meninges, how blood is supplied to the brain, and brain cells. This will be the last post of this series, so if you’ve stuck all the way through, you’re almost on your way to becoming an expert on the anatomy of the brain!
