The History of Alzheimer’s Disease: A Closer Look

Alzheimer’s disease has long been the primary ailment to cause dementia with its symptoms known for being associated with old age since the age of the ancient Greeks. However, it is not a normal part of aging to develop Alzheimer’s. Though it typically only affects people above the age of 65, early-onset Alzheimer’s can afflict people younger than 65.

One of the most unfortunate factors of this disease is that it is a progressive neurodegenerative disease and only worsens with time, usually over the course of years, first beginning with the loss of memory and progressing to the compromise of language and movement.

Though dementia and senility have been known by humanity probably since our evolutionary dawn, “Alzheimer’s disease” was only first described in 1906 by German psychiatrist Dr. Alois Alzheimer. A few years earlier in 1901, Dr. Alzheimer had been studying a mental patient named Auguste D. who was fifty years old at the time and exhibiting worsening signs of dementia, notably paranoia and memory loss. He studied her for years and only when she died in 1906 did he publish his findings¹. In the autopsy of Auguste D., Dr. Alzheimer also noticed that certain parts of her brain had shrunk and withered.

Alzheimer’s Disease

The neurological changes that Alzheimer’s disease could cause would not be found for several more years until 1931 when the electron microscope was invented with an ability to magnify to a greater extent than ever before. This new technology would allow neurons to be studied in much more detail.

Today, we are quite familiar with how Alzheimer’s microscopically afflicts the brain. The brain is a vast and impressive system of 100 billion neurons that connect with each other in a complex network, allowing for the communication of information from various parts of the brain, much like many busy highways. Some parts of the brain relay sense information, such as smell, touch, taste, sight, or hearing, while other parts allow for complex cognitive functions such as thinking, perception, and consciousness.

These many neurons, of course, need fuel in the form of oxygen to generate their electrical impulses. Alzheimer’s does something very unusual to this smooth-flowing highway of information: it creates plaques and tangles. Tangles are tangled fibers of a protein called tau that occur within neural cells, while plaques are buildups of another protein called beta-amyloid between nerve cells.

Interestingly, many people as they age develop some plaques and tangles, but often this development does not progress to Alzheimer’s disease. People with Alzheimer’s disease, on the other hand, develop plaques and tangles much more predictably and begin in parts of the brain responsible for memory.

The Details

It is not known exactly what tangles and plaques do to the brain, but it is believed that they block the ability of neurons to properly communicate with each other. However, the more serious symptoms of Alzheimer’s, and the death of the patient from the disease, are caused by the death of neurons in the brain. In 1968, special cognitive scales were invented to measure the volume of brain tissue that was damaged by the disease. In general, it is often found that the brains of Alzheimer’s patients have less mass compared to healthy brains and weigh less.

There are various symptoms of Alzheimer’s with the early symptoms being quite mild compared to the later, more severe symptoms. For example, early symptoms include difficulty remembering new information and confusion. As the disease progresses, people with Alzheimer’s may start to experience mood changes, worsening memory loss, and confusion about the time and the place they’re in. As the disease worsens and more neurons continue to die, it may be hard for the patient to speak, swallow, or walk².

As of today, there is no cure for Alzheimer’s disease. However, it continues to be intensely researched and scientists continue to try and enlighten the more unknown aspects of the disease. As more about the disease is uncovered, the closer science may get to finding a cure.

References:

1. Sauer, Alissa. (2013). “History of Alzheimer’s: Major Milestones.” Alzheimers.net. Retrieved from https://www.alzheimers.net/history-of-alzheimers.
2. “What is Alzheimer’s Disease?” Alzheimer’s Association. Retrieved from https://www.alz.org/alzheimers-dementia/what-is-alzheimers.