Month: September 2019

The concept I am choosing to write about is Magnetic Resonance Imaging or MRI’s. I was never sure what an MRI was, but I knew it was similar to an x-ray. An MRI is different in from an x-ray in many ways. An MRI is a machine that allows doctors to look at soft-tissue with out opening the body. This allows doctors to see tumors, tears, or narrow slices. The MRI machine allows doctors to see very detailed and important parts of the body without making any incision. This machine was a huge advancement in the medical field because it can see almost every detail; this is due too the machines great spatial resolution. The spatial resolution on an MRI scan can go millimeters, so the doctors can see all the tissue and organs. My first experience with an MRI was this past school year. During the school baseball season, I dislocated my shoulder, an obvious injury the doctor can see from outside the body. However, the doctor told me it was necessary for me to receive an MRI in-order to tell if I tore any of the muscles in my shoulder. I had gotten x-rays in the past, but the MRI experience was much different. I laid down on a bed and was put into this big machine. After 15 minutes or so I was pulled out of the machine and was sent home. When my results arrived, they found further injury. The doctor told me I had torn my labrum and had chip out on my shoulder socket due to my shoulder being popped back in. The MRI allowed the doctors to see past just the dislocation and discover that I had torn a ligament. This related back to class because doctors always use MRI’s. They are often used to study the functions of the brain. Doctors can have patients perform task while they use an MRI’s to watch different functions of the brain. This was a huge advancement because previously they would have to open the body but now they can use this machine to study vital organs while patients complete tasks that make the brain work in different ways.

The nervous system is controlled by electrical and chemical signals between nerve cells called neurons. These neurons (shown below) communicate with each other through chemicals called neurotransmitters. When a neuron receives an electrical impulse of a certain magnitude, it travels from the dendrites to the axon and down to the axon terminals. This is called an action potential. The neurotransmitters are stored in the axon terminals, and are released into the synapse, which is the space between two neurons. These neurotransmitters fit into the dendrites of the receiving neuron like a lock and key and set off an action potential in that neuron, creating a chain reaction.

(from https://medicalxpress.com/news/2018-07-neuron-axons-spindly-theyre-optimizing.html)

Different neurotransmitters produce different psychological and physiological responses. For example, serotonin affects mood, hunger, sleep, and arousal. Low levels of serotonin lead to adverse effects. Chronically low levels of serotonin lead to clinical depression. Agonist drugs can mimic the effects of certain neurotransmitters, which is why Prozac has proven to be effective in treating depression by imitating serotonin in the body.

Even people who do not have a clinical mental illness are affected by different levels of neurotransmitters on a daily basis, and there are different ways that we can naturally increase serotonin levels. My favorite way to improve my mood by increasing neurotransmitter levels is exercise. Most runners describe a “runner’s high” after intense physical activity. Of course, this is different from getting high from drug use, but some components are similar. Like Prozac, many recreational drugs are agnostic drugs that mimic the effects of serotonin and other mood-enhancing neurotransmitters. Exercise causes the body to naturally produce more serotonin and endorphins, which improves the mood.

A little bit of exercise can make a big difference. Sometimes I jog for ten minutes if I don’t have time for a full workout, and even that is enough to improve my mood for the rest of the day. Understanding the biology of why we feel the way we do can help us to make choices that improve our overall mental health.

 

In our fourth lecture in Psychology, we learned that everything psychological is simultaneously biological through beginning to understand the complex function of the nervous system.  More specifically, we learned about the information system built from billions of interconnected cells called neurons. A neuron is the basic working unit of the brain; it is a cell that transmits information to other nerve cells, muscle, or gland cells. Neurotransmitters can often be referred to as “chemical-messengers”. They are molecules that transmit information between neurons, or from neurons to other parts of the body. You may have heard that depression is the result of a “chemical imbalance” in the brain. According to Harvard Health Publishing, “Research suggests that depression doesn’t spring from simply having too much or too little of certain brain chemicals. Rather, there are many possible causes of depression” (“What Causes Depression” 2019). My grandmother has suffered from depression for many years now. In 2018, she was hospitalized for her depression for several months in a rehabilitation center in Altoona. This was an extremely hard time for my family. My grandmother has been forever changed by her depression. She went from a being an energetic and loving individual, to becoming inverted and distant. She barely talks anymore. I hope and pray that with time and treatment she will be back to herself again. A reason for my grandmother’s severe depression could be attributed to how her nerve cells communicate with each other. According to Harvard Health Publishing, “Brain cells usually produce levels of neurotransmitters that keep senses, learning, movements, and moods perking along” (“What Causes Depression” 2019). To further explain, in some people who are severely depressed like my grandmother, the complex systems that accomplish this malfunction. Receptors can be both over and under-sensitive to a specific neurotransmitter. One of the big neurotransmitters believed to influence depression is serotonin. My grandmother takes medication that functions to help her low serotonin levels reuptake. I hope with more research, my grandmother can find a medication that works for her.  

MLA Citation

“What Causes Depression?” Harvard Health Publishing, Harvard Medical School , 24 June 2019, www.health.harvard.edu/mind-and-mood/what-causes-depression.

Top down processing is one of the ways the brain processes information. It is fundamentally different than bottom up processing.  Bottom up processing is when the brain takes in as many sensory details as it can and then forms an image, sound, or thought in our head. Top down processing is when the brain utilizes information that it already has, such as past images, experiences, or feelings to process information. Top down processing is the reason we don’t need all the letters of a word to be able to read it, and why some people see different images when shown the same picture.

In sports, especially baseball, top down processing is used all the time. The game simple moves too fast to be able to use bottom up processing.  If a player tried to take into account all the details of a pitch; like speed, spin, location, and movement, as it was coming towards them, the ball would be in the catchers mitt before they could even think about swinging. I remember my coach always telling me that all thinking should be done before you get in the box. Once you’re up to bat, your mind should be clear. This is why players need to rely on years of experience and pitcher’s tendencies during an at bat. For instance, if a pitcher throws a curveball, you are not telling yourself in your head that its a curveball coming towards you, your brain is just able to recognize it and tell your body how to react because it has seen so many curveballs before. This is why many hitters struggle with lefties or with pitchers who have unique deliveries or arm slots. These pitchers are less common, so the brain has less prior knowledge about what the ball looks like coming out of their hand and how it will move. This makes it more difficult for the brain to use top down processing and instead has to rely on bottom up processing, making it harder to stay relaxed and focused while up to bat.

Below is a video of multiple pitches overlapped into one video. As you can see, all the balls start in the some place, but wind up in totally different places at different times. If the batter was to use bottom up processing, they would never be able to recognize the pitch in time. Instead, the batters brain is using prior knowledge about what the pitcher is likely to throw in that count and how the pitch looks compared to other pitches he’s seen in a prior at bat or even a different game. Overall, top down processing is what allows baseball players, and other athletes, to make decisions so quickly without taking into account every sensory detail they are experiencing.

The human body has so many functions that control us on a daily basis but the body makes up an excessive amount of signals that we cannot always come to terms with or understand why our bodies send these signals to us when certain situations happen. The sympathetic nervous system is one of those signals that our body sends us when we experience a stressful, overwhelming or high intensity situation or activity. The sympathetic nervous system makes up a part of the autonomic nervous system which contains two divisions; the sympathetic and parasympathetic nervous system. Both of these divisions are controlled by our body and we simply do not have control over them because our bodies naturally send these signals to us when we experience an overwhelming, stressful situation and then the aftermath of our bodies returning to regular heart race and blood flow. In other words, when our bodies prepare to experience something intense, our sympathetic nervous system activates which causes our blood flow to increase, excessive sweating, dilated pupils, heavy breathing and speedy heart rate and then as we work through the experience the parasympathetic nervous system helps our body get through it and return to that “safe” feeling. The sympathetic nervous system is a feeling that no person can escape entirely because at some point in life everyone faces a situation that scares them, makes them angry, sad, stressed or excited. All of these emotions will result in the body activating the sympathetic nervous system to prepare you for this sensational feeling. A time where my sympathetic nervous system came into play was last semester in my Geary Hall dorm where my two friends decided to wake me up from a dead sleep and pretend they were an intruder. There was no rhyme or reason for my friends to play this joke on me other than pure boredom and the fact that they lived 2 floors above me. It was probably around 12am when I fell into a deep peaceful sleep until I was woken up from an alarming, aggressive loud knock on my door. I sprung up out of bed and stared at the door for about 2 seconds until the loud banging picked up again. My stomach fell into my toes practically, I was dripping sweat, my body felt like it was throbbing, my heart was pounding so hard that I felt like I could literally hear my heart beating and I could hardly think straight. In this moment I had no place to run and only so many places to hide so I squatted on my bed frozen not knowing where to go or what to do. The banging continued and within a few more seconds I heard, “OPEN THE DOOR.” With all of my emotions coming into play I began to come to terms with the fact that I was going to die. I could not even control the way I felt and I could not control my heart rate or excessive sweating, in fact all I remember was feeling like I was going to pass out and die. All of a sudden I heard my phone ring and saw a text saying, “ITS ME DON’T CALL THE POLICE.” In that moment my whole body felt relieved and I felt absolutely exhausted but safe and happy at the same time. There was no better feeling in the world then that moment walking over to my door and being able to open it knowing I was not going to die and it was just my friends. This situation that I went through of anxiety and fear related to the sympathetic nervous system because my body responded the exact way it was supposed to. My blood flow increased, my heart was racing, I was sweating and I experienced that feeling of my muscles being so tense. My situation is also related to the repercussions of the parasympathetic nervous system. My body then came back to all of its normal levels after that feeling of anxiety and fear left my body and I was able to relax by feeling safe and comforted. The bodily functions are all very interesting but these divisions of how our nervous systems react and prepare us for certain situations really prove how much our bodies can really do and produce for us.

 

Work Cited

“Nervous System: To Lift or to Rest?” CrossFit Holland Michigan – Try a Free CrossFit Class, www.crossfitlakeeffect.com/nervous-system-to-lift-or-to-rest.

“Fight or Flight: The Sympathetic Nervous System.” LiveScience, Purch, www.livescience.com/65446-sympathetic-nervous-system.html.

Recently in class, we have discussed the visual system. Upon going over this system, we were able to discuss how this system works and the different areas of the eye. One thing that I thought was very interesting was phototransduction. This is the conversion of light energy into neural impulses. I find it very interesting that no two people can see the exact same in terms of colors and perceptions. From what I understand, the stimulus input of light energy varies for everybody. On the electromagnetic spectrum, humans are only able to see “visible light”. This “visible light” is seen through the wavelengths and intensity. The wavelength is the distance from the peak of one wave to the peak of the next. This is related to how humans perceive hue, or color. In addition, the intensity (brightness/lightness) refers to the amount of energy in a wave. This is how humans are able to perceive brightness. However, the different perceptions vary from person to person. I believe that this goes along with the saying of, “My color red is not the same as your color red.”

However, something that is held in common is that all humans are able to see with their eyes. This may seem like an obvious statement, but it actually is very complex when thinking about how the different parts of the eye work together to perceive and interpret colors and visuals in their own unique way. The first part of the eye that we learned about is the cornea. The cornea is the transparent tissue where light enters. Next is the iris, which is a muscle that changes the opening in the eye by expanding and contracting. This opening is known as the pupil, which also lets light in. The lens in the eye focuses rays of light on the retina, and the retina holds sensory receptors which process visuals and send the message to the brain.

Learning about the eye caused me to recall an experience of my own where my eye was injured. In the middle of a soccer game, the ball was kicked into my face at exactly the right angle to hit my eye directly on. This hit actually caused a bruise on my cornea. Upon the initial hit, the vision in my affected eye partly went black. When one part of my eye was injured, I can assume that this messed up my visual system, causing the impaired visual. At the eye doctor, I was able to see a type of x-ray that showed my eye. I remember the doctor showing me the different parts of my eye, all of which we discussed in class. I was also able to actually see the bruise that was on my cornea through this “x-ray” process as well. I thought that it was really cool to be able to discuss the parts of the eye and how these parts of the eye work together to create the visual system in which we are able to perceive things. I was then able to relate the class discussion to actual images of my own eye that I could recall seeing in the picture.

Psych blog post 1

Click on the picture of the youtube video!

The Automatic Nervous System is divided into two parts, the sympathetic nervous system and the parasympathetic nervous system. The sympathetic part allows you to use up the energy you have saved within, whereas the parasympathetic is just relaxed and stores your energy to regulate it. I am going to be talking about the sympathetic nervous system and am about to share with you a story of a good example of this “flight or fight” situation. I woke up in the middle of the night because I heard something downstairs. At first I thought it was my dog so I let it go. I heard the noise again and decided to go downstairs to take a look. I started to get scared because most of the lights were off and I couldn’t see much, but I kept on hearing footsteps. I do not know why I didn’t think it would be anyone in my family. I guess I was too tired to even think at that point, but I kept walking down the stairs and I finally got to the bottom. I heard another noise and at this point I was very scared. My heart was racing, my palms were sweating, and I could feel the nervousness all the way up to my head, and I wasn’t thinking straight. Then I don’t know what happened to me but I sprinted into the kitchen, screaming, to find the “stranger” in my house. When I got in there me and my sister were standing face to face both screaming and began yelling at each other. We scared each other for no reason. In that moment, I do not know what happened to me and how my adrenaline popped into my body so quick, but after hearing about the sympathetic nervous system, I knew exactly that that’s what kicked in. The sympathetic nervous system arouses the body and that is when your flight or fight response comes into play. When you’re in a scary or rough situation and you don’t know what is going to happen next and your heart starts to race and you start to sweat, that’s how you know you are going through the sympathetic nervous system. And if it wasn’t for that, I would have never caught my sister!

The nervous system is the body system concerned with transmitting signals to and from the brain through cells called neurons. This system can be divided into two main subsystems called the central nervous system and the peripheral nervous system. Within the peripheral nervous system, another division can be made into the autonomic and somatic systems. The somatic system is the system responsible for voluntary skeletal movements. This allows us to be able to control how we move our skeletal muscles whenever we decide to move them. The sensory neurons within this system are responsible for carrying information from sensory receptors located mainly in the tissues of the body back to the central nervous system. The motor neurons are the cells that take information from the central nervous system back to the skeletal muscles, which is what enables us to voluntarily move in one way or another.

 

The somatic nervous system differs from the autonomic nervous system in the way that it is voluntary, versus the autonomic system which functions involuntarily and controls the internal organs and glands in the body as opposed to the skeletal muscles. These differences are further shown in the following illustration:

A time where I definitely feel the somatic system in action is during dance rehearsal. While we are rehearsing, we are expected to be able to quickly learn and repeat steps and movements that are taught to us at a fast pace. Our muscles have to move quickly, precisely, and at the right timing. While many different parts of the brain and nervous system are all working together at the same time to make this happen, the somatic system is the system responsible for sending signals from the brain to the skeletal muscles through motor neurons, creating these desired quick and precise movements. There are many times where some of the movements involve something as small as a head tilt or hand placement that have to be identical between a team of 20 individuals. Without the somatic system, we would not only lack the ability to make these fine tuned movements, but we would not have the ability to move at all whether that includes dancing, walking, or even opening your mouth to speak. This is why the somatic system is extremely necessary for human survival.

Staff, E. (2017, December 3). Difference between the Somatic and the Autonomic Nervous System. Retrieved from https://difference.guru/difference-between-the-somatic-and-the-autonomic-nervous-system/