May 9, 2014

An Introduction to the Science Behind Dementia

Dementia Science

As promised we have written this article in order to educate you a little on the science behind the disease that has brought you to this page, dementia.

Most of us know the symptoms and visual effects of dementia, but we believe it’s important to understand why these occur. We have done our best to make this an enjoyable and easy to understand read, and hope you get something out of it. So without further ado, let’s begin!

Forms of Memory

To start with, it’s important to understand the difference between short and long term memory.

Short-term memory is the capacity for holding a small amount of information in mind in an active, readily available state for a short period of time. It’s believed that the duration of short-term memory is in the order of seconds.

There are two types of Long-term memory:

  1. Declarative (knowing something, e.g. facts, images, etc…). This is consciously controlled.
  2. Procedural (knowing how to do something, e.g. ride a bike, tie shoelaces, etc…). This is unconsciously controlled.

Information can be stored in the long-term memory indefinitely.

So What Is Dementia? 

In basic terms, dementia is the general decline in all areas of mental ability.

There are many causes of dementia that affect the brain in different ways and determine the symptoms that a person experiences. These are the parts of the brain that are affected to cause each symptom:

Memory loss and impairment is associated with damage to the Hippocampus.

brain hippocampus

The Hippocampus belongs to the limbic system (complex set of brain structures primarily responsible for emotional life, and are greatly involved in the formation of memories) and plays important roles in the consolidation of information from short-term memory to long-term memory. There is one hippocampus on either side of the brain.

In Alzheimer’s disease, the Hippocampus is one of the first regions of the brain to suffer damage; memory loss and disorientation are included among the early symptoms.

The retention of visual memories, processing sensory input, comprehending language, storing new memories, and emotion are affected by damage to the Temporal lobes. There are two temporal lobes, one on each side of the brain.

Spatial awareness, navigation and other sensory information can be affected by damage to the Parietallobes. Again – on each side of the brain.

 brain lobes

How Do These Get Damaged?

All cells are like miniature factories, producing thousands of proteins with specific functions to keep the cell alive. A malfunction can occur if a protein is altered, or if too much or too little is made. Sometimes, the consequences are so severe that a cell dies.

Death of neurons (the cells of the brain that transmit information through electrical and chemical signals) is the main cause of dementia. This is often related to malfunctions in the communication system that a neuron needs to survive. However, if the immune system of the brain is too active and causes inflammation, this can also damage cells. Unlike most cells, when neurons die other cells do not divide and replace them. Therefore most forms of dementia are progressive and cannot be reversed.

Can Dementia Be Prevented?

Many believe that dementia, and in particular Alzheimer’s is hereditary. For the most part this is not true. The vast majority (99%) of cases are not passed down through the family. In general, only rare forms of dementia such as Huntington’s disease are shown to be hereditary.

Unfortunately there is no certain way to prevent all types of dementia. As always, a good healthy lifestyle is the best you can do. So in order to reduce your chances of developing the disease the NHS recommend that you:

  • Eat a healthy diet,
  • Maintain a healthy weight,
  • Exercise regularly,
  • Do not drink too much alcohol,
  • Stop smoking (if you smoke) &
  • Make sure you keep your blood pressure at a healthy level.

To Conclude

We hope you enjoyed reading this article and it helped you to understand a little more about the science behind dementia.

As always we value your feedback and invite you to comment, join us on social media, or even get in touch with us to find out about our products that can improve the lives of dementia patients and carers.

This article was written with the help of students of The University of Glasgow Medical Faculty and the following references:

The NHS Dementia Guide
Alzheimer’s Society –


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