Coming back home

After this long tedious journey, we've finally returned back to base and are able to examine the spoils of our endeavor under a more informed eye. We place the cerebrum and cerebellum under a microscope and are amazed by the clear differences.

The cerebellum is made up of grey matter, and looks more dense. Conversely, the cerebrum is made up of white matter which looks far less dense and appears to have more space shown through the bubbles present. 

Cut and conquer

Up until now, our journey has been predominantly passive and non-violent. Alas we must cut and conquer to truly understand the brain. Hopefully the inhabitants understand.. This is for the greater good.

After the carnage has been taken care of, we finally get what we came for. The understanding of the inside of the brain. The first gaping difference we notice is the obvious presence of ventricles; specifically the third, fourth and lateral. All of them contain cerebrospinal fluid while also protecting the brain from trauma, the third and fourth connected by the cerebral aqueduct. The close proximity of these ventricles to certain parts of the brain can't help but raise the question; does the proximity of a part of the brain to one of the ventricles measure the importance as they seem to have been given priority? It's definitely possible. The third ventricle is close to the brain stem gang we met last time, starting from the spinal cord and ending at the cerebellum and pons. That part of the brain having importance is really no surprise, as damage to these would stop basic functions such as breathing. It appears the thalamus and corpus callosum have also been betsowed with the honor of being near ventricles. The thalamus is responsible consciousness, sleep and sensory interpretation, all undeniably important. If the thalamus is damaged, sensory stimuli that should be interpreted as harmless, such as a gentle touch may be interpreted incorrectly as severe pain. So this particular location appears justified. Next we have the corpus callosum, responsible for allowing the two hemispheres to intercommunicate, snugly placed near the lateral ventricle. Once again, understandably protected as without it, the two hemispheres of the brain would function as entirely incapable of communicating which is a dangerous implication. The others left are not located near a ventricle although still interesting to study; the hypothalamus is responsible for controlling the pineal gland which explains its close proximity to it. The septum pellucidum does not perform any function itself but when it isn’t there, it can cause seizures, problems with coordination and dysfunction of the hypothalamus. After the first cut was made, three more parts were visible. The caudate nucleus plays an important role in storing memories and works as a feedback processor, important to development and use of language. The internal capsule is a massive layer of white matter separating caudate nucleus and thalamus from the lentiform nucleus while connecting grey matter and insulates nerve impulses. The putamen aids movements of limbs. All of these don't seem to have any relation with each other, despite close proximity.

Barely scraped the surface..

The first day we land on this unknown territory, we're wary of what to expect. It's wet and bumpy terrain, with obvious divisions separating the expanse. Let the exploration begin!

First thoughts

As far as the eye can see when we first touch down, there's an overwhelming amount of cerebrum. No wonder it's so big, it's responsible for sensing, thinking, learning, emotion, consciousness, and voluntary movement. Wow. As we look around, we notice some clear divisions. This land is quite obviously not all cerebrum. There have obviously been some divisions, but the separation seems to have been friendly. We see neurons from different regions all communicating with each other, there's even a postal service called Synapse Fast Inc. that has been established to keep relations friendly and prevent any hostility. They send neurotransmitters to let each other know what's happening. Even within these little regions, neurons still seem to respect each other's space, having sulci to keep them apart and inhabiting these bumps called gyri. 

Second thoughts

After trekking through the cerebrum, the next region we hit is the cerebellum, which controls fine muscle movement and balance. It's also a pretty big region although not nearly as massive as the cerebrum. They say opposites attract because they balance each other out. Ha, balance. Oh terrible wordplay. But that must be why they're so close to each other. Cerebrum is the one handling all conscious activity getting plenty of credit while the cerebellum is the unsung hero providing little things like balance so the cerebrum can handle voluntary movement at all. We almost hit the spinal cord after that but that isn't necessarily part of the brain so we stay away from it for the most part. It's main function is to connect the peripheral nervous system to the brain. It connects directly to both the cerebellum and the medulla. For the cerebellum, it must be how it gets all of the information on balance since the PNS contains all the nerves in the body. As for the medulla, that's responsible for involuntary actions such as circulation and breathing, both very important and entirely involuntary. The close proximity to the spinal cord which is essentially the messenger from the body must be so essential actions such as those are served first and the body doesn't risk death. From the medulla, we reach the pons, which is involved in sleep and arousal. Also something essential for survival and just plain functioning. Without sleep, we risk losing some incredibly important capabilities such as memory and in extreme cases, lack of sleep can result in death by falling asleep at the wheel of a car. So here we've found yet another important part of the brain with somewhat involuntary functions, all snug together to make sure they get the messages first to keep the essentials going. We then end up back in the cerebrum but in the bottom this time. In the near middle is the oculomotor nerve, which controls eye and eyeball movement which frankly makes plenty of sense. This nerve probably fits right in with the cerebrum, bonding over all their voluntary work no doubt. But then there's the pituary gland.. well it doesn't exactly come to mind as voluntary. It's in charge of the endocrine system, which keeps tabs on factors such as growth hormones. We feel like this little guy would it in better with the involuntary crew back near the spinal cord but it must be here to keep the cerebrum informed on base desires so it can make voluntary decisions based off of it. The optic chiasma and nerves are responsible for transferring the information from the retina into the brain while the olfactory bulb recieves neural input from the nasal cavity. Both of them are responsible for senses located on the face and makes sense being close together near the cerebrum as they are often necessary to make observations and thus elicit emotion and conscious thought.