Dementia vs Alzheimer’s? A Dementia Overview

Learn about the key distinctions between dementia and Alzheimer's disease, including causes, symptoms, and progression rates. Discover how brain imaging scans can aid in diagnosis and understand the role of plaques and tangles in Alzheimer's.

Dementia vs Alzheimer’s? A Dementia Overview
Dementia Versus Alzheimer's Disease

What is the difference?

Dementia is the umbrella term for conditions that cause memory and cognition problems.

It is important to determine the primary cause of the memory and cognition problems. Dementia and Alzheimer’s are often confused with each other. This is because they impair brain functioning. The origins of most dementias are, for the most part, recognized and understood. The origin of Alzheimer’s and reasons why some people develop the disease… are not yet understood.

What is Alzheimer’s Disease?

Several discernible clues that are detectable through brain imaging scans can tell doctors whether someone is suffering from AD:

  • Noticeable shrinkage of brain tissue
  • Noticeable enlargement of ventricles (spaces filled with cerebrospinal fluid that act as a cushion for the brain)
  • Atrophy of the hippocampus, the area responsible for memory
  • Cortical atrophy, the area responsible for higher reasoning, judgment and abstract thinking
  • Evidence of abnormal electrical activity provided by EEG scans
  • Plaques and tangles

Plaques and tangles are abnormal strands and cluster of protein fragments. They inhibit communications among nerve cells and choke the classic Alzheimer’s brain. Plaques form when beta amyloid pieces begin clumping together. This occurs because of their chemical stickiness.

When clumps grow large enough they impede cell-to-cell synaptic signaling. The individual suffering from these plaques will develop a variety of cognitive deficiencies. Especially with recognition, attention, and memory.

An electron microscope can easily detect tangles affecting neurons. This is due to their disorganized structure. Strands composed of tau protein are parallel and organized. This allows vital molecules and cell parts… to be transported along these track-like strands.

When something happens to tau proteins, the brain’s ability to keep the strands organized is lost. This results in tangles and knots that disintegrate. They fail to transport essential nutrients to all parts of the brain.

Dementia vs. Alzheimer’s  Progression

This involves determining the time between someone developing Alzheimer’s symptoms… to the time it takes before an accurate diagnosis is made.

Signs of AD can start 20 to 25 years prior to an official diagnosis.

Dementia patients receive a diagnosis within weeks of showing symptoms of brain impairment. Especially if they have suffered a stroke or a medical condition… that reduces blood flow to the brain.

Dementia vs Alzheimer’s–A Dementia Overview

So what is dementia when Alzheimer’s disease does not cause it?

Some of the features of dementia that are different from Alzheimer’s includes:

Dementia can be age-related–Alzheimer’s is not.

As we age, the ability of our organs, tissues and vessels to operate at optimal levels… begins to deteriorate. Theories of aging attempt to explain why healthy human bodies rapidly decline in functioning… after age 60 or 65 but none have been substantiated with conclusive evidence.

Dementia accelerated by:

Chronic high blood pressure

Parkinson’s disease

High cholesterol


Stroke (vascular dementia) is due to blood vessels experiencing irreversible damage. This with the vessels’ inability to provide the brain with enough blood-borne nutrients and oxygen.

People diagnosed with a certain dementia types do not have the standard plaques and tangles… that are always found in the brains of AD patients.

According to an article published in the International Journal of Geriatric Psychiatry (2009) titled…. “Apathy is a prominent neuropsychiatric feature of radiological white-matter changes in patients with dementia” by M. Jonsson et al,…  Brain imaging scans reveal acute changes in the white matter of the brain… occur in dementia and elderly patients.

White matter consists mostly of myelinated axons and glial cells. These cells are responsible for… transmitting electrical signals between lower brain areas and the cerebrum.

Healthy white matter appears whitish-pink on MRI and CT scans. White matter affected by dementia is blurred and darker than it should be. This is due to tiny vessels not supplying enough blood to keep the white matter functioning.

Dementia vs Alzheimer’s–Personality Changes

Alzheimer's Disease and Personality Changes

These two cognitive disorders exhibit different pathological disturbances. These affect different pathways in the brain. Certain cognitive and personality changes are attributed to one disorder… more than the other.

For example, apathy occurs in half those suffering from non-Alzheimer’s dementia. While aggression and irritability occurs more AD patients than dementia patients.

This suggests to researchers… when comparing dementia vs Alzheimer’s. …Patients with dementia suffer more “deep brain” or neocortical damage than AD patients.

Dementia Personality Changes

People with Alzheimer’s dementia experience more mood changes, paranoia and extreme anxiety. This is more than those with non-AD dementia , who have damaged blood vessels… due to strokes, high cholesterol and hypertension… Have a greater chance of having audio and visual hallucinations. This is higher than in patients with Alzheimer’s.

Dementia Caused by Brain Tumors or Head Injuries

Dementia symptoms… caused by brain tumors or head injuries, are temporary, if the condition is not severe. And it can be successfully treated.

Once a benign, operable brain tumor is removed…the brain swelling decreases. The person suffering dementia symptoms usually recovers full use of their cognitive abilities.

Subdural hematomas often cause dementia-like symptoms. These are also eliminated if surgical decompression of the area is successfully employed.

Understanding the difference between dementia vs Alzheimer’s comparison is often blurred. Helping family members recognize the early signs of Alzheimer’s… as well as dementia, can lead to early treatment.

A Dementia Overview

Have more questions? Check out the Frequently Asked Question section of the website. You will find a lot of different questions answered directly.
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