Sensory adaptation is when there is diminished sensitivity as a consequence of constant stimulation. What comes with sensory adaptation is attention and attention span. Attention is partially a mental effort some of it is effortless. We can not focus on too many things as an individual because we will miss key parts if we try to on more than one. I have first hand experience with this because when I study, I will be reading my notes or writing something down when someone in the room tries to talk to me. I try to continue to write as I listen to what they have to say and it just doesn’t work. I either have to stop writing or ask them to “give me a second”. This ties back with the idea that we can not really do more than 1 thing at a time effectively. If i tried to do both, I would subconsciously not really listen to the person, or I would forget completely what I was supposed to be writing down and have to restart.
Category: Uncategorized
The Parasympathetic Nervous System
The Parasympathetic Nervous System
The autonomic nervous system is the part of the nervous system that controls and regulates the internal organs without any conscious effort by the organism. The autonomic nervous system is comprised of two opposite sets of nerves, the sympathetic and parasympathetic nervous systems. Both of which are responsible for the involuntary functions of the human body. Although I will be discussing the parasympathetic nervous system.
The parasympathetic nervous system works in opposition to the sympathetic nervous system, alerting the rest and digest responses. These responses fix the energy that was reduced in the previous sympathetic activity. Some of these responses can include digesting food, crying, or salivating.
The parasympathetic nerves emerge in the middle of the spinal column extending to the central nervous system. The axons of this system are long and extend throughout the rest of the body. Since these nerves originate in the spinal column, it does not typically require conscious thought to create a reaction. Without the parasympathetic nervous system, the monitoring and regulation of everyday body processes would be impossible. It plays a vital role in maintaining both mental and physical health by helping the body to calm down from stress reactions, decreasing blood pressure, and altering energy from other body processes to indicate flight or flight response.
The parasympathetic nervous system is something we react to everyday. Sometimes our stress is caused by something psychological. It could even be from anxious feelings from an upcoming deadline or trying to get to work during a busy rush hour. Disregarding the cause of the stress, high levels of anxiety also cause the human body to release stress hormones. These hormones result in changes that range from a pounding heart, quickening of breathing, and sweating. All of the body’s combined reactions to stress are known as the fight or flight response. In my life, I suffer from stress daily. Whether it be something small like talking to new people or even something big like taking an exam, stress floods my entire world. However, knowing how to manage this stress is something I have been able to excel with.
I took my first ever college exam 2 days ago. I started studying a week before the exam and even stayed up late the night before to make sure I knew everything as perfect as I could. When I woke up the next morning, I was sweating and shaking. My hands were clammy and I felt the knot in my stomach grow tighter and tighter as each minute passed by. Once I arrived at my classroom I was shaking but I knew I had to calm myself down in order to do well on my exam. I stood outside, took a drink of water, a deep breathe, and stepped inside. By doing this, I was demonstrating the rest and digest, parasympathetic nervous system. This system teaches us to calm down from stress. I was able to relax myself as well as understand everything would go well. From being able to relax, I was able to excel better on my exam and this technique helps me grow as a person in everyday life.
How the Nervous System Operates
The nervous system is a complex structure within our bodies that allows us to sense and perceive the world around us. At its most basic level, the nervous system consists of a large array of neurons spread throughout the body which work to send messages to our ultimate control center, the brain. Neurons (known commonly as nerves, nerve cells) relay signals from a part of the body experiencing an internal or external sensation or stimuli to the brain for processing and response. So, imagine you do not know if a stove is hot or not, so you place your palm on it to test the temperature. Pain signals from the nerves in your hands travel toward the brain to register this pain and you reflexively pull your hand away. This is the work of the nervous system.
There are two major subdivisions of the nervous system: the central nervous system (CNS) and the peripheral nervous system (PNS). The peripheral nervous system consists of neurons known as sensory neurons and motor neurons that connect the body to the central nervous system. Motor neurons send signals from the brain to the muscles and typically help with general movement. Sensory neurons pick up stimuli from sensory receptors throughout the body to the central nervous system. The central nervous system consists of the brain and the spinal cord, two of the vital components of signal transfer in the nervous system. This is where our reflexes are controlled. The spinal cord receives a signal from a sensory neuron and the signal splits, one signal being sent back to the original sensed area and the other being sent to the brain. I can demonstrate this with a personal example. During my first semester of college, I had a chemistry lab where we had to use dry ice (which is incredibly cold). I wore gloves to pick up the clump of dry ice, but I felt it burning into my palm, so I instinctively dropped it. So, the sensory neurons in my palm felt the burning stimuli, which sent a signal to my spinal cord. My spinal cord split that signal, sending one message back to my palm, prompting me to drop the dry ice, and another message to my brain, telling me that what I just touched was way too cold to lay flat in my palm.
From the peripheral nervous system, there are two more divisions. One is the autonomic nervous system and the other is the somatic nervous system. The somatic nervous system is the division that controls voluntary movements of skeletal muscles. This is what allows us to move when we sense that we must move, like if we are in danger. The autonomic nervous system is responsible for the movement of the body’s internal organs, such as the heart. Some examples of the autonomic nervous system in action is heart rate and the dilation of our pupils when exposed to bright light. Further dividing the autonomic nervous system is the sympathetic and parasympathetic nervous systems. The sympathetic nervous system has the task of arousing the body, inciting what we know as our “fight-or-flight” response. When we are threatened by something, our heart rate rises, and this is from the sympathetic nervous system. The parasympathetic nervous system does the exact opposite and calms our body. This will lower our heart rate or blood pressure after an incident in which the sympathetic nervous system has risen these attributes.
To illustrate these concepts, I will use another personal example. When I studied abroad in the Netherlands, I was walking with a friend when I could feel we were being followed. As I sensed him approaching us, my heart began to beat faster and I started sweating. This was the work of my peripheral nervous system; my autonomic and sympathetic nervous system activating my fight-or-flight response. Because of this, my legs started to move faster, due to a signal from my brain to my motor neurons to pick up the pace. This was my somatic system kicking in. Once my friend and I made it to our destination safely, I was able to calm down; I stopped sweating and my heart rate slowed. This was my parasympathetic nervous system at work, reversing the actions of the sympathetic nervous system. The nervous system controls just about every aspect of our body’s movements and actions in some way or another.
Nativism vs. Empiricism
The beginning of psychology goes all the way back to Ancient Greece, around 300 BC. The psychologists at that point believed in two concepts. These concepts caught my eye and reminded me of an experience I went through this past summer. The concepts were called Nativism and Empiricism, typically referred to today as nature and nurture. Nativism is described as “the idea that our thoughts, ideas, and characteristics are inborn”, otherwise not learned through any experience, and are just how our brains and bodies are wired. Empiricism, on the other hand, explains that knowledge is gained through experiences or senses.
Throughout my high school years and into college, I have babysat many kids and seen a lot of different behaviors and had different experiences with all of them. However, this summer was probably the most eye-opening experience of them all. I nannied nine-year-old twins, Jake and Adam, two or three days every week. As the summer progressed, I realized that nativism was more evident with the twins than empiricism was. Jake and Adam were both raised the same way and given equal treatment and attention, yet this summer I noticed extreme differences between the two. Jake was always ahead in his summer reading and summer workbooks, whereas Adam struggled daily to be focused on reading and wasn’t motivated to get ahead in his summer work. In addition to this, Jake was athletic and wanted to be outside all the time whether he was scootering, playing basketball, or swimming in his pool. Adam was more into arts and creativity. He also wanted to spend every day that I was there inside.
The concept of nativism vs. empiricism really stuck out to me this summer. Despite being exposed to the same experiences and being together their entire lives, Jake and Adam were completely different people. This showed me that experiences cannot shape people, and that characteristics of a person are inborn and cannot be changed.
Tubal, Michael Caesar. “History of Psychology.” LinkedIn SlideShare, 30 June 2015,
www.slideshare.net/michaeltubal/history-of-psychology-49985298.
Hemispheric Specialization
HEMISPHERIC SPECIALIZATION
Our brain is split into two hemispheres, the right and the left, divided by a longitudinal fissure. Each side of the brain specializes in function, hemispheric specialization. The right side of the brain specializes in things like art and music perception but controls the left side of the body. While the left side of the brain specializes in language and analytical classification but controls the right side of the body. We have learned that the two hemispheres process different information but work together by sending signals back and forth to make our body function as one. Our brain uses what’s called the Corpus Callosum to do this. When one side of the brain is affected, everything is affected.
When I was younger, my grandmother, who we called “memom”, suffered a severe stroke. A stroke is when arteries, which carry oxygen to the brain, gets blocked or bursts. This is also known as an ischemic stroke. My memom survived the stroke but was kept in the hospital for several weeks in order to do rehab. I remember going to the hospital and visiting my memom. The first thing I noticed about her was that her speech sounded very different. She had a lot of trouble speaking and forming sentences. Her speech was very slow and slurred and hard to understand. I asked my parents why memom was talking funny and they told me it was because of the stroke. I never understood why until now.
After learning that the hemispheres of the brain have specific functions, I can finally understand why my memom had a lot of trouble speaking again after her stroke. When the oxygen was cut off from her brain, it was cut off from the left side which affected it severely. The left hemisphere controls language. Since her left hemisphere was affected due to the lack of oxygen, it caused her to barely be able to speak. My memom was put through speech therapy in order to learn how to speak somewhat normal again. It would take a while for her because she was older which meant her neuroplasticity had significantly decreased and she had to retrain her brain again. She never fully regained perfect speech, but she was able to talk without a slur anymore. I finally understand how each hemisphere plays a role in everything we do and that if one side is affected, something we do daily can also be affected.
Works Cited
Ramsey, Leona. “Slide Player.” Slide Player, https://slideplayer.com/slide/10844873/.
What is a Stroke? (n.d.). Retrieved from http://www.strokecenter.org/patients/about-stroke/what-is-a-stroke/
Neurosurgery
This past summer, I had an internship position at a local hospital. During this internship, I was able to observe in the operating room every morning. I got to see a variety of surgeries, but the neurosurgery I witnessed was a surgery I will never forget. My mentor for the summer is in the cardiothoracic department, so I did not know much about neurosurgery going into the operating room. The surgeon explained many concepts to me that I have found myself connecting to this class, such as the functions of the cortex and hemisphere specialization.
Before the surgery, the team “mapped” out the brain using advanced fMRI technology, like we have talked about in class. The fMRI allowed them to overlay previous MRI scans with the scans taken directly before the surgery, which was really interesting because the MRI scans were so precise. The surgeon then connected a metal probe to the machine with the scans. Using the mapping technology, he was able to stick the probe on the patient’s head and see everything going on before having to “open them up”. If you are interested in this technology, see the following link, just note that there are some graphic images(https://cen.acs.org/articles/93/web/2015/02/Raman-Technique-Helps-Surgeons-Excise.html).
Using the probe, the surgeon worked with a neurologist to assess the patient’s motor functions. The neurologist used electrodes that he had previously connected to the patients to test the patient’s reactions. Sending signals through the electrodes would cause the patient’s motor cortex to function. For example, when the surgeon asked for right side movement, the patient lifted their right arm up while completely unconscious. The unconscious mechanisms used were due to the parasympathetic division of the somatic nervous system. The patient was calm and able to function voluntarily due to the electrode signaling.
While observing the surgery, I was able to watch the surgeon resect a tumor bordering the occipital lobe of the patient. He used the probe as much as he could to determine the precise location of the tumor and the lobes of the brain so that he did not cause any damage to the patient. If he would have hit the occipital lobe and damaged it, the patient would have had problems with vision post-surgery. This was the biggest risk of the surgery, and the surgeon was able to completely remove the tumor without causing any damage. He assessed the patient after “closing” using the probe and another fMRI scan. It is really interesting to take this class and be able to connect it to experiences I had this past summer. Learning about the function of the brain and seeing it in person, in action, is something that I will cherish.
Citations:
Arnaud, Celia Henry. “Raman Technique Helps Surgeons Excise Brain Cancer.” Chemical and Engineering News, 11 Feb. 2015, https://cen.acs.org/articles/93/web/2015/02/Raman-Technique-Helps-Surgeons-Excise,html.
Serotonin and Prozac
Prozac, an antidepressant, is a selective serotonin reuptake inhibitor. SSRI’s are used to keep serotonin, a chemical nerve cell that contributes to the feelings of happiness and jubilance, bound to a receptor for longer than usual, thereby increasing its effect. Likewise, without proper serotonin pathways, some forms of depression arise and create mental health issues as serotonin is a type of neurotransmitter, a chemical substance that causes transmits impulses and messages to another neuron or fiber, which parallels with mood.
When delving into the biology of transmission of Prozac, serotonin will flee from one neuron through channels and adhere to the receptors of another neuron. This fires signals that eventually regulate mood. Serotonin can disengage from receptors and go back to the neuron it previously came from. It is able to do this because serotonin channels are reversible. Prozac goes to the gap between the presynaptic neuron and postsynaptic neuron and blocks the serotonin channel, inhibiting the reversible reuptake of serotonin. This forces serotonin to sit on the receptor site of the second neuron that helps transmit the signal that helps mood, which eventually increases serotonin levels in the body.
Two years ago, I went to the University of California, Los Angeles for a month in the summer with my friend to take classes and get an understanding of college living. For the first two weeks, my friend was never in a good mood, always wanted to sleep, and did not have much of an appetite. I did not think anything of it at the time as I just assumed she was homesick or did not like UCLA and the program we were enrolled in. With her being in a constant negative mood, I started to dislike the program and also started to become worried about her.
We were both enrolled in the same classes, one coincidentally being abnormal psychology. This abnormal psychology class was not what I expected it to be; however, it was a very thought-provoking class because numerous people in the class had mental illnesses that they were very open about.
One day during the class discussion, my friend started talking about her mental illnesses: anxiety, attention deficit hyperactivity disorder, and a small amount of depression. She said that her depression was sparked by a chemical imbalance from her prescribed medications for her anxiety and ADHD. She then continued by saying she was recently prescribed Prozac and a different combination of medications; and the reason she was never in a good mood was because her body and mind was still regulating to the medication. It all began to make sense. She was lacking serotonin and needed the Prozac to increase her serotonin levels so she could enjoy the wonders of life and at the time, the experiences UCLA had to offer.
MRI’s to diagnose brain injuries
Almost our entire body is made up of water molecules which house an even smaller particle known as a proton. These protons serve as tiny magnets which are highly sensitive to magnetic fields. During a Magnetic Resonance Imaging scan (MRI), the protons in our body line up in the same direction. Short bursts of radio waves are then sent to certain areas of the body, which will cause the protons to knock out of their orignial alignment. This sends out radio signals, which are picked up by receivers. These signals provide information about the precise location of the protons in our body and also help to distinguish between the various types of tissue in the body. This is because the protons in different types of tissue realign at different speeds and produce their own distinct signals. The signals from the millions of protons in our body are all combined to create a very detailed image of the inside of our body.
MRI scans are effective at helping to diagnose many internal medical conditions. For example, when I was 12 years old I went skiing with my family up in the Poconos. I decided to try one of the steepest hills at the mountain and ended up taking a massive fall which cause me to hit my head on the snowy ice. In additon, I was not wearing a helmet, which I now realize was a major mistake on my part. The moments following the fall were hazy and patchy and I experienced alot of headaches and neck pain in the days following the fall. When we returned home, my mother and I decided that it was best to take me to the hospital to see if I had suffered from any brain injuires, which is what we were both questioning.
After talking with the doctor and relaying my symptons to him, he took me for an MRI scan, among multiple tests to check for any internal brain damage. I was then taken into a special room which held the large machine I would be laying in. The scan lasted about an hour and took multiple images of my brain, which it was able to do by sending radio waves to the priotons in my body which, in return, send out signals across the body. Luckily, after thouroughly reviewing the scans, the doctors were able to confirm that I did not have a brain bleed or any interanl damage, which I was relieved about. I had only suffered from a minor brain contussion.
Without the technology and high spatial resolution of magnetic resonance imaging scans, I may not have been able to recieve accurate results about my serious but luckily not life threatening injury. We are extremely lucky to have access to this type of advanced technology right at our fingertips, and I am grateful that it granted me relief over potenially a potenially damaging outcome.
“MRI, Magnetic Resonance Imaging Mayfield Brain & Spine Cincinnati, Ohio.” Mayfieldclinic.com, 2018, mayfieldclinic.com/pe-mri.htm.
Lam, Peter. “MRI Scans: Definition, Uses, and Procedure.” Medical News Today, MediLexicon International, 24 July 2018, www.medicalnewstoday.com/articles/146309.php.
Hello world!
Welcome to Sites At Penn State. This is your first post. Edit or delete it, then start blogging!