Analysis of memory pathology in the case of Clive Wearing
Extract
It is a small explanation of the pathology caused by HSV-1 in the case of Clive Wearing and how it affects his memory. At the end of the article, you can find the link to the documentary that is the subject of this analysis.
Long-term memory (LTM)
Short-term memory (STM)
The problem with Clive is a case of herpes simplex encephalitis (HSV-1), which caused necrotizing inflammation of the brain. The areas typically affected are the orbital portions of the frontal lobes and the lower and medial parts of the temporal lobe. It all started with the viral infection. The doctors were unaware of what was happening. Clive’s symptoms included fever, headache, disorientation, memory loss, and flaccidity. This resulted in him suffering from both anterograde and retrograde memory loss; he is unable to remember anything beyond a period of 7 to 30 seconds, nor can he recall past memories. This is due to significant damage to his long-term memory (LTM). In fact, he always says he doesn’t remember anything when asked if he recalls something. For example, if he has spoken with someone, he replies: “I have never heard a word. I have never seen a human being since I got sick. You are the first 4 people I have seen in 30 years.” He lives in a temporal disconnection with the world. He describes it as: “It’s the same as death. There is no difference between night and day. No thought.” He also suffers from auditory hallucinations, believing he hears background music. He is unable to live alone because he cannot remember anything or orient himself. He says it’s like death, it’s simple. No thoughts of any kind. There are no dreams. Despite all this, he can recognize his handwriting, his wife, some of his children, and even play the piano. It’s one of the most challenging cases, also because it happened at a time when there wasn’t complete knowledge of the disease. Had he contracted it two years later, it wouldn’t have affected him in the same way. But it’s also not the most extreme case because encephalitis can cause death, which would have been certain if he had contracted it two years earlier. There is no hope for improvement, likely because it is a necrotizing disease. The damaged parts will not recover.
Clive’s condition is utterly incapacitating. It has almost entirely changed his usual behavior. The first idea that comes to mind regarding behavior is personality. It seems not much is left of what Clive used to be, at least, that’s what his children say. Thankfully, there is one aspect of his personality that his son mentions has remained: when Clive becomes aware, he analyzes what is happening. At one point, he comments that it will be a very curious case for the doctors. The fact of being curious has not been lost from his personality. As for the motivations in his life, they have been cut short. He cannot be a director as he was before the illness because he cannot remember how this task was done. Nor can he have new goals because he is incapable of remembering new things. At the very least, he also cannot remember events that he would like to motivate him. He cannot remember what Rugby is and, therefore, despite liking it, he cannot have the goal of playing it.
Regarding cognitive processes, among others, his perception, attention, and learning are affected. A very clear example is when his wife explains that they are in front of their house, and Clive is unable to identify it. Firstly, his perception is altered because he cannot remember that it is his house and, perhaps, does not know what a house is. He also cannot learn because perception is altered, and memory makes it impossible. There can be no learning if memory cannot store new concepts. Continuing with the same example, he cannot solve problems because many cognitive processes are altered due to memory loss. He cannot choose which is his house; the yellow or the white one; he cannot know what his wife does for a living. Understanding language will also be affected. He must have access to the meaning of words, even if it is unconsciously. He also needs to be able to access the syntactic understanding of language. Otherwise, it would be like listening to an unknown language. It’s impossible to understand.
In summary, what we can understand is that memory is a system that works in connection with other processes. But more significantly, memory can be placed at the center of the axis of many other systems.
Clive’s hippocampus is primarily affected. The hippocampus is part of a neural system that fits in connection with the entorhinal, perirhinal, and parahippocampal cortex. This is part of the medial temporal lobe. It’s an important system because it will be in charge of processing information to be encoded and stored in the LTM. It will largely be responsible for accessing new information. When this area has been affected, we face an impossibility of processing information in the LTM. In fact, the hippocampus is responsible for transferring information from STM to LTM. We subdivide LTM into two systems: the declarative memory consisting of a) episodic memory, responsible for evoking past memories or experiences, and semantic memory, more related to “general culture or general knowledge.” I personally call it this because it can answer specific facts, like knowing who discovered gravity, for example. But it’s also knowledgeable about language, the meaning of words, etc.; b) And non-declarative memory, intertwined with semantic and therefore declarative memory; it’s harder to define, especially because the concepts it stores are often difficult to translate into a linguistic code. However, it is related to skill acquisition. Recapping, Clive has a damaged hippocampus, part of the LTM. But it seems not all areas are completely damaged. The general fact of learning new concepts or fixing experiences due to the hippocampal system’s impairment causes him anterograde amnesia. If we go to declarative memory, which must be accessed to transfer information to the central executive, we find that his episodic memory is almost completely affected. This results in retrograde amnesia. He can remember his wife, likely due to the emotional component. As he loved his wife very much, there was a high emotional component. This is probably why he remembers his wife. Semantic memory seems to be better preserved than the former, and he can access linguistic matters, probably because the Broca area, located in the left frontal lobe, is not affected. However, his semantic memory is very much affected. This would explain why he doesn’t properly understand some words but does others. On the other hand, there’s non-declarative memory, which seems to be better preserved than the rest. As I said before, the hippocampus is in the medial temporal lobe. The functions of non-declarative memory are largely located in areas independent of the medial temporal lobe. This fact enables him to play the piano, even though he cannot remember how he does it because he doesn’t have access to part of the declarative memory.
As for STM, it seems not to be too affected except for the connection with the central executive. It prevents him from sending new information to the LTM (anterograde amnesia) and retrieving old information (retrograde amnesia). As for sensory memory, it remains intact.
In the link below, you will find the reference video: In the link below, you will find the reference video: https://www.youtube.com/watch?v=8suclojMp0k&feature=youtu.be
