Introduction to Emotions

The basic definition of emotion says that an emotion is a feeling state involving thoughts, physiological changes, and an outward expression or behavior. Emotions are very important because they influence our everyday lives, affect the choices we make and shape our lives. There are many theories that attempt to examine why and how we experience emotions. One of them is James-Lange Theory which argues that an event causes a physiological arousal first and then an interpretation of this arousal. 

 Only after our interpretation of the arousal we can experience emotion. If the arousal is not noticed or is not given any thought, then we will not experience any emotion based on this event. EXAMPLE: You are walking down a dark alley late at night. You hear footsteps behind you and you begin to tremble, your heart beats faster, and your breathing deepens. You notice these physiological changes and interpret them as your body's preparation for a fearful situation. You then experience fear.

Another example is Cannon-Bard Theory which argues that we experience physiological arousal and emotion at the same time, but give no attention to the role of thoughts or outward behavior. EXAMPLE: You are walking down a dark alley late at night. You hear footsteps behind you and you begin to tremble, your heart beats faster, and your breathing deepens. At the same time as these physiological changes occur you also experience the emotion of fear.

One of the main roles of emotions is to allow humans to survive and be successful in the world. Nature developed our emotions over millions of years of evolution. By showing emotions we reveal our needs and wants. Our emotions also have the potential to serve us as a delicate and sophisticated internal guidance system. Our emotions alert us when natural human need is not being met. For example, when we feel lonely, our need for connection with other people is unmet. When we feel afraid, our need for safety is unmet. When we feel rejected, it is our need for acceptance which is unmet. Fear is an example of emotion which is important for our survival. Back then, being afraid was important for survival of our species because our distant ancestors could see when it was needed to run away - otherwise they might have been killed. Fear signals to your brain that your survival is under threat upon which chemicals and hormones are released to prepare your body for the needed action.

Alzheimer's Disease

   Alzheimer's disease is a physical disease of the brain. During the course of the disease plaques and tangles develop in the brain leading to the death of brain cells. Alzheimer's always starts in the median temporal lobe, so it affects the memory first. In its early stages memory loss is mild but in its late- stages it causes loss of ability to carry on a conversation and respond to the environment. Alzheimer's Disease is the most common form of dementia. Dementia is a general term for loss of memory and other abilities that may interfere with normal daily life. Alzheimer's Disease accounts for about 50 to 80 % of all dementia cases. Alzheimer's disease symptoms become worse over time. It is a lethal disease, meaning that there is no way out and it will eventually end your life. Alzheimer's was discovered in 1906 by German neurologist Alois Alzheimer, but it was only recently brought up how widespread this disease actually is. 

The video we watched in class, "The Forgetting", was about Alzheimer's Disease and its explanation in depth. They estimated the number of people with this disease to five million and that the number is still increasing. There were also mentioned experiments on animals and how are the scientists trying to develop drugs that will cure the disease. There were also introduced some stories of the people with this disease. In the video they said that Alzheimer's Disease affects the relatives more than the person with the disease because the person with the disease eventually forgets who are his or her relatives and it can be quite traumatic for their loved ones.
       There is so many new things I have learned about Alzheimer's Disease in the class. Personally, I don't know anybody who has this disease so I was never really interested in it and therefore I didn't know a lot about the disease. After we covered this topic in class, I finally became aware of how widespread it is and how awful are the consequences of it. From the video "The Forgetting" I learned that Alzheimer's Disease can "tear all the memories that form who you are." Some of the patients in the video say that they "lost themselves"  because memories form who we are. I also learned that relatives of the person suffering from this disease are affected really badly because the person that they knew and loved is slowly disappearing.

The Case Study of H.M.

The case study of Henry Molaison (H.M.) has been one of the biggest contributions to neuropsychology. Henry Gustav Molaison banged his head after being by a bicycle rider when he was nine and after that developed severe seizures. The scientists did not see into his head and were not even sure if the seizures had to do something with the accident. After 18 years, Molaison went to see Dr. William Beecher Scoville, a neurosurgeon at Hartford Hospital because he was blacking out frequently, had devastating convulsions and the quality of his life radically worsened. Dr. Scoville decided that the best option to help H.M. would be to surgically remove a portion of his temporal lobes, in particular hippocampus. After the surgery, seizures abated but there still were some other consequences, especially on his memory. A number of scientists were trying to figure out what were the consequences by giving H.M. memory tests and studying him thoroughly. After some tests, the scientist found out that H.M.'s short-term memory was completely fine; he could hold thoughts in his head for about 20 seconds. However, since it was impossible for him to hold onto these short-term memories, scientists concluded that hippocampus is responsible for forming and maintaining long-term memories. Yet H.M. was able to recall some of the earlier memories, he still had obstacles with placing them into the correct place in time. He was also unable to move memories from short-term to long-term stores so therefore he no longer had the ability to create new memories that could be later recalled. There were a lot of things learned on this case. He helped scientists understand the biology of learning, memory and physical dexterity, as well as the fragile nature of human identity. Before H.M. case, scientists believed that memory was widely distributed throughout the whole brain and that it was not dependent on any particular neural organ or region. However after this case they found out that there is a part in our brain that is responsible for forming long-term memories. This part is called hippocampus and it is located in the medial temporal lobes. Therefore, the case study of H.M. was really essential to development of neuroscience and to understanding the biological concept of memory.            “The study of H. M. by Brenda Milner stands as one of the great milestones in the history of modern neuroscience,” said Dr. Eric Kandel, a neuroscientist at Columbia University. “It opened the way for the study of the two memory systems in the brain, explicit and implicit, and provided the basis for everything that came later — the study of human memory and its disorders.”