This article aims to focus on the impacts of Alzheimer’s disease, dementia, and similar neurodegenerative diseases from the standpoint of the accumulation of personal experiences. In taking this position, it’s assumed that humans are born tabula rasa, which means that they are born as a blank slate. However, physiological arguments can be made against this position, such as the existence of instincts. But as this article aims to explore the impacts of experiences, specifically memory, on rational agency and such, those arguments tend to fall out of the scope of this discussion.

One hallmark of many neurodegenerative diseases, such as Parkinsons and Alzheimer’s disease, is the presence of the aggregation of abnormal proteins. With these proteins being explored in previous articles, these proteins have been scrutinized in the ongoing research to cure these diseases. However, even though they may not end up as the underlying cause of the diseases, these abnormal clusters do indeed cause harm to neighboring brain tissue.

Many abnormalities have been found in the brains of patients who had neurodegenerative diseases such as Alzheimer’s disease. One of the most notable abnormalities has been found on the cellular level, namely clusters of toxic proteins called beta-amyloid plaques (Aß). These plaques, as well as neurofibrillary tangles and tau tangles, have been the focus of research for an extremely long time with multiple treatments targeting those plaques. Although none of these treatments have really worked, and the underlying cause of Alzheimer’s disease is still unknown, it is still good to know about these proteins and how they play into the disease.

The fascination surrounding the brain has only sped up as scientists decode one of the most complicated and powerful organs to exist. With the brain making up a tiny fraction of the body weight but hogging up around 20% of the body’s blood supply, the brain has greater processing power than current supercomputers. However, one of the most special features of the brain is to recall and to reimagine the past. This is what is called memory. Memories are a mysterious thing. While not fully understood, memories constantly shape identities and are central to the human experience. However, Alzheimer’s disease, a disease marked by memory loss, is becoming more and more common as people age.

Ever since two scientists noticed dark blots in the brain matter of patients with dementia and similar illnesses in 1892, something known as the amyloid cascade hypothesis has made itself known throughout the scientific community. Although bearing an intimidating name, the hypothesis is relatively straightforward. Before the 1900s, those dark blots were already correctly identified as plaques of unwanted material that tangled around neurons. Later, Alois Alzheimer, the namesake of the neurodegenerative  disease, made the hypothesis that these plaques were a possible cause of dementia.  Soon, in the latter half of the 1900s, those proteins were identified. The main protein that composed of the tangle was discovered to be Amyloid-ß (Aß). Aß was found to cluster up in the brain quickly and mess with brain functions (Lowe, 2022).