Unit 6 Reflection

This unit was about the nervous system in its entirety, and some key themes and understandings were that the brain, although specialized to some extent, can be adapted to new environments and situations in order to better serve the body, and communicates within itself to divide up the work that needs to be done; dysfunctions of the brain are able in many ways to teach us how the brain normally works; and lastly, that the brain needs to be able to work with many other parts of our nervous system in order to truly function at its best.

The Clay Brain

We first started off by learning about the main parts and functions of the brain, the center of our nervous system. The brain is structured from bottom to top by the spinal cord, hindbrain, midbrain, and forebrain, and the closer parts are to the spinal cord, the more basic its movements and functions are. Then there are the parts of the brain, which include the brainstem(comprised of the medulla oblongata, pos, and midbrain); the cerebellum, which controls the body; the thalamus, which sorts data and sends it where it needs to go; the hypothalamus, which maintains homeostasis; the posterior pituitary, which sends out hormones; the cerebrum, which is in charge of integration; and the cerebral cortex, divided into 4 lobes and controls higher function thought and action. Those four lobes are the frontal lobe, which is involved in speaking  and is the "executive; the parietal lobe, in charge of sensation; the occipital lobe, in charge of vision; and the temporal lobes, which include auditory areas. As seen from the article "A Woman With a Hole in her Brain", loss of a certain part of the brain can result in a lack of ability to perform functions that that part of the brain does. The Sheep Brain Dissection also documents our journey in learning about the anatomy of the brain, as well as the Clay Brain.

We next learned how the brain works together to communicate and divide up the work amongst its various different parts. the whole idea of brain lateralization is that the brain "divides and conquers" when it conducts neural functions and cognitive processes between the right and left hemispheres of "A Woman Perpetually Falling". Other important characteristics of the brain are sensory areas, which contain the homunculus(the perception that your brain has of your body in accordance to the sensitivity of various parts of the body), and motor areas, which control muscle movement(where the right and left hemispheres come into play again).
the brain to make processes more efficient. The two sides(which control opposite halves of the body under a contralateral division of labor)communicate through the corpus callosum that connects the two. Contrary to this school of thought is the idea of brain plasticity, where parts the brain are able to take on functions of their missing or dysfunctional neighbors because the brain adapts and evolves in different environments constantly; this can be evidenced by the examples found in the reading

My Senses graphic organizer

Th mechanics of senses were discussed next, and we learned about special(or organ-specific) and somatic(or body) senses, which are received by receptors of all types. Sensory adaptation is the occurrence where our receptors are exposed to stimulus for so long that you no longer receive the message. The main specific senses were discussed, such as sight/vision, hearing, smell, and taste, and the corresponding organs, receptors, and sensory cells were identified as well. dissected a sheep eye in order to learn more about how light travels through the eye, and the functions of the different parts of the eye. Dysfunctions of sight include myopia(near-sightedness), hyperopia(far-sightedness), glaucoma, and cataracts; for hearing a choclear impact may be required allow sound waves to stimulate the auditory nerve. Taste and smell are lesser known for their dysfunctions, but we discussed how they(and sight and hearing) work as well. For this part of our learning, we

Neurons, probably the most important part of the nervous system, followed senses, and we learned that the 3 functions of the nervous system are sensation, integration(processing of sensory input), and motor function. The nervous system is divided into the central and peripheral nervous systems, the latter of which is divided into the sensory and motor divisions. The central nervous systems comprised of the brain and spinal cord, while the peripheral nervous system is made up of the surrounding nerves. The sensory division carries nerve impulses from the body to the brain, and the motor division carries nerve impulses from the brain to the muscles and glands. Subdivisions of the motor division are the somatic nervous system which consciously controls skeletal muscles, and the autonomic nervous system, which regulates involuntary or autonomic events. The automatic nervous system is at last divided into sympathetic and parasympathetic, which wither produces a change or the opposite that change. Neurons themselves have 5 main parts: dendrites, axons, axon terminals, the synaptic cleft, and the synapse. They are classified according to function or structure, but all of them conduct electrical signals much the same way. The nerve impulse starts off in the resting state, until something sets it off for depolarization(a switch between positive and negative charges). Depolarization occurs and propagation sends the signal across the neuron until it reaches to axon terminals to release neurotransmitter, and then the neuron is again repolarized to do its job once more.

Lastly, we covered the disorders of the CNS and PNS. Some diseases of the CNS are meningitis, an inflammation of the meninges, and epilepsy, a condition of the brain causing seizures. PNS disorders include the shingles, a reemergence of the chicken pox virus, and neuralgia, the sharp shock of pain that follow the path of a nerve. Addiction, believe it or not, is a disease as well, as it meddle with the brain's structure, pathways, and chemicals to create craving, compassion, loss of control, and continued use despite consequences in addicts.

Readings that we did this unit were "A Woman With a Hole in her Brain", "A Woman Perpetually Falling", both articles that discussed the topic in their title and relate to brain dysfunction, anatomy, and plasticity. Others included "How to Become a Superager" that explained how some elderly people could retain their younger minds through challenging themselves mentally all of the time(again, related to plasticity and evolution of the brain), "Fit Body Fit Brain" that discussed(like the previous one) how exercise can improve one's brain capacity, and "How We Get Addicted" that addressed the numerous ways that addiction can be considered a disease(relating to our nervous system disorders notes).

Definite strengths this unit included keeping up with readings and participating in class, but some weaknesses were seen in putting things off till the last minute and having a lot of work to make up. Studying for the test, too, was definitely not the best I could have done, which relates to my New Years Goals of trying to come up with better studying techniques. I did try to try new things this unit with drawing diagrams to help me study(mostly of the nervous system), but the main problem that occurred was the lack of time I had to prepare. Next time, I'll endeavor to invest more time into properly studying for the test. To end on an inquisitive note, some things that I am curious about are what parts of the brain/how much of the brain can be lost until brain plasticity is no longer able to occur, and how headaches occur.