Author: sqj5470

There are many ways that we learn. Some of these ways include reinforcement and punishment, but some learning happens without us even trying. Classical conditioning is a type of learning where an organism learns to associate stimuli. This isn’t something you actively learn, you just end up learning to associate two things from recurrences. Classical conditioning can be broken into pieces to explain how and why it works. It begins with an unconditioned stimulus, and an unconditioned response. The unconditioned stimulus is a certain stimulus that elicits an unconditioned response from a subject. This unconditioned response is not learned, it is just a natural response to the stimulus. In Pavlov’s experiment, both stimulus and response are seen with a dog salivating when it is presented food. The presentation of food is the unconditioned stimulus, and the dog salivating is the unconditioned response. After this is determined, you can decide on a conditioned stimulus that will elicit a conditioned response. The conditioned response is a learned response to the conditioned stimulus. This response wouldn’t just happen naturally due to the stimulus, but the subject learns to respond to the stimulus in a certain way. Once again referring to Pavlov’s dogs, the dogs were presented food at the sound of a bell, and eventually the bell caused the dogs to salivate even without food being presented. Here, the bell is the conditioned stimulus, while the salivation is the conditioned response.

I’ve actually had direct experience with classical conditioning, involving my sister’s bird. My family got a bird when I was little, and that was fine. Although, he became very attached to my sister, and in return absolutely despised me. I didn’t go near him ever because he would bite me. In general, I just avoided him as much as I could. In this case, the bird biting me was the unconditioned stimulus, and me staying away from him to avoid pain was the unconditioned response. Keeping away from him worked just fine, until he started to fly over and bite me. This happened quite a few times, as one of the routes out of the house goes past his cage. His room is also close to our kitchen, so I could sit at a barstool and he would just fly over. After he attacked me enough times, just the sound of his wings flapping would immediately cause me to be alarmed, and run in order to avoid him. Even today if I hear a sound too similar to his wings flapping it alarms me. The actual sound did not cause me any pain, but I learned to associate the sound with him biting me. Here, the conditioned stimulus was the sound of his wings flapping, and the conditioned response was for me to start running to get away. This doesn’t affect me as much as it used to because I don’t live in my parents’ house anymore, but when I go back I’m still very wary to stay as far away from his cage as possible.

Depth Perception is the ability to judge distances.  Our eyes have certain ways of focusing that allow us to decide when things are closer or farther away from us. Within the overarching concept of depth perception there are two types of cues: monocular and binocular cues. Monocular cues require one eye, and can determine a variety of things, such as relative size, Interposition, aerial perspective, linear perspective, texture gradient, and motion parallax. Relative size is where the object that casts a smaller retinal image is further away. Interposition is where one object blocks another, and the one blocking the other is closer. Aerial perspective shows that the hazier the part of the image is, the further it is away. Linear perspective is where parallel lines converge with distance. Texture gradient is where the further away an object is, the less detailed it is. Lastly, motion parallax is where closer objects appear to go faster than further objects. All of these cues only employ the use of one eye, as opposed to binocular cues, which use both eyes. Binocular cues include retinal disparity and convergence. Retinal disparity is how we combine the two images from separate eyes and make a 3D picture. This is why it seems that we view a cohesive plane rather than two different perspectives. Convergence is how our eyes move together to view close objects, and further apart to view distant objects. The experience I am going to tell has to do with convergence.

As I said above, convergence is our ability to focus on something close or far away from us. This has been a bit of a struggle for me, as my right eye is slightly lazy. When I focus on an object, such as a pen, close to me and move it closer, eventually my right eye gives up and goes back to a neutral forward position. Because of this, I was given an exercise of sorts from my doctor in order to work on my focusing. I was given a string, with 3 large colored beads. Each were a different color: red, yellow, and green. The point was to hold the string up in front of my eyes, so the colored beads were going away from me. Each was a different distance apart, and I would switch from color to color to practice focusing on each. This exercise showed the ability of convergence, as my eyes had to move closer together to focus on the closest bead, and further away to focus on the further bead. Both of my eyes had to work together to focus on each bead, and it helped to strengthen the abilities of my right eye so I keep this ability.

We all know the feeling you get when you find yourself in a sticky situation. Our hearts beat faster, our hands get sweaty, and you feel like you are ready to make a run for it. Whether this particular experience actually presents danger to us or not, our body has ways of preparing itself to fight or flee from anything harmful. This feeling is thanks to our nervous system. The nervous system in the human body is split into two parts, the central nervous system and the peripheral nervous system. The central nervous system is our spinal cord and brain, while the peripheral nervous system is split into the autonomic and somatic nervous system. The somatic nervous system deals with things we can control, such as voluntary movements of skeletal muscles. What we know as the fight or flight response is thanks to the autonomic nervous system, which controls the self-regulated actions done by our body. More specifically, the autonomic nervous system can be split into the sympathetic and parasympathetic nervous system. These two are opposites in a way, as the parasympathetic nervous system is for calming, while the sympathetic nervous system is for arousing. The sympathetic nervous system is what wakes our body up and prepares us in a time of potential danger. In a situation that might be potentially harmful, our body makes us very alert so we have the best chance at survival. Our pupils dilate, our heart rate increases, we stop digesting food, and our adrenal glands secrete epinephrine and norepinephrine. All of these effects serve as a way to prepare us for any dangerous situation. 

Experiencing the fight or flight response is very common and happens to everyone from time to time, even if no real danger is present. For example, when I was much younger, I had to stay at home alone while my parents went away for a weekend. This was fine, as I was comfortable with being alone, but being a bit younger and less used to an empty house, I was easily startled by the occasional noise I would hear. At one point I was in the living room watching tv when I heard the front door begin to open. I knew this should not have been happening, as my parents were out of town. I remember running to the bathroom and locking the door to hide from whoever had entered my house. At this point, my heart was beating so fast and my hands were sweaty. My body was preparing me to either fight the unknown person or run for my life. A bit of time passed, and I went back out into the kitchen to investigate. There was a loaf of Easter bread on the counter that our family friend had stopped by to drop off, and everything was totally fine. Obviously this was not a dangerous situation for me, but I didn’t know it wasn’t a threat, and neither did my body. Though, in a time of not knowing, my sympathetic nervous system was making sure I was prepared in case it was a truly dangerous situation. As far as our bodies are concerned, you’re probably better off safe than sorry.