What Are Neurodegenerative Diseases?

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What Are Neurodegenerative Diseases?

Neurodegenerative Diseases

Neurodegenerative diseases (aka degenerative nerve diseases) are a number of conditions that affect how your body operates.

These conditions are typically brought on by age but not always. Some research shows that these diseases have become more prevalent in recent times, partly due to an increase in the elderly population across the globe.

Neurodegenerative diseases include conditions such as Alzheimer's disease and Parkinson's disease. Neurodegenerative disorders are progressive, which means that they get worse over time. Unfortunately, there's currently no cure, and this progression can't be stopped.

Symptoms of Neurodegenerative Diseases

Neurodegenerative diseases share a lot of common symptoms. Symptoms of these diseases progress in severity the longer you live with the condition. While medication can help manage and sometimes even slow progression, it can't stop it.

Some of them include:

  • Impaired mental functioning 
  • Loss of muscle control 
  • Taking a longer amount of time to learn new skills 
  • Memory loss 
  • Disorientation 
  • Emotional blunting 
  • Social withdrawal 
  • Hallucinations
  • Delusions
  • Depression 
  • Experiencing unwanted thoughts and feelings 

Identifying Neurodegenerative Diseases

When diagnosing you with a neurodegenerative disease, the first thing your doctor is likely to test is your cognitive function. 

A decline in cognitive functioning is a common symptom of all neurodegenerative diseases. However, each condition under this umbrella also has its own diagnostic criteria.

Your doctor might also order brain imaging tests like an MRI to confirm a diagnosis. There is ongoing research into the early detection of neurodegenerative diseases.

A test is done for the presence of microRNAs (miRNAs), which might contain potential biomarkers for neurodegenerative disease. A miRNA is a single-stranded molecule that plays a role in regulating gene expression. 

Causes of Neurodegenerative Diseases 

Below are some of the causes of neurodegenerative diseases.

Neuronal Damage

Neurodegenerative diseases are thought to be caused by damage to neurons in your brain. Neurons make up your nervous system which includes your brain and spinal cord.

Unlike some parts of your body, when a neuron gets damaged, it's unable to replace itself. And, as you age, these neurons die. In fact, as you get older, the brain shrinks.

Neurodegenerative diseases cause these neurons to die. When these neurons die, you experience symptoms that affect your mental functioning, movement, and ability to breathe or speak.

Environmental and Genetic Factors

It's not very clear what brings on most neurodegenerative diseases. Most of these conditions are thought to be caused by a combination of environmental and genetic factors like long-term exposure to toxins and certain chemicals.

In some cases, relatives can pass down mutated genes that can cause you to develop a neurodegenerative disease.

Abnormal Proteins

Abnormal proteins in the brain have also been linked to many neurodegenerative diseases. These abnormal proteins can cause nerve cells in your brain to die. With Alzheimer's disease, a protein known as beta-amyloid has been linked to the development of the condition.

Synuclein is another abnormal protein that has been observed in the brains of people with Lewy body dementia, Parkinson's disease, and multiple system atrophy.

Risk Factors for Developing Neurodegenerative Diseases 

Certain risk factors can increase your risk of developing a neurodegenerative disease. The most significant risk factor for developing a neurodegenerative disease is old age.

As you age, nerve cells in your brain are more likely to die. These factors include having conditions such as cardiovascular diseases or experiencing brain trauma. Other factors include: 

Types of Neurodegenerative Diseases 

There are many different forms of neurodegenerative diseases. Some of the most common are detailed below. 

Alzheimer's Disease 

Alzheimer's disease is one of the most common neurodegenerative diseases in the United States today. Research shows that around 6.2 million people may have the condition as of 2022.

Common symptoms include:

  • Getting lost
  • Memory loss
  • Personality changes

There are two forms of this disorder: late-onset Alzheimer's disease and early-onset Alzheimer's disease. The former is more common and affects people over the age of 60. The latter is rare and can develop in people who are between the ages of 30 and 60.

Amyotrophic Lateral Sclerosis

Amyotrophic lateral sclerosis (ALS), also known as Lou Gehrig's disease, is an uncommon type of neurodegenerative disease. It targets the nerve cells in your brain that control your voluntary muscle movement.

As with most neurodegenerative diseases, ALS is progressive, which means symptoms worsen over time.

Early signs of the condition include muscle stiffness and weakness. With time, this will progress into an inability for a person with the condition to walk, eat, speak or even breathe.

Huntington's Disease 

Huntington's disease is a condition that causes you to lose control over your body. It also causes cognitive decline.

Early symptoms of the disorder include:

As the condition progresses, more severe symptoms such as difficulty walking and swallowing, increased involuntary movements and personality changes develop.

Lewy Body Dementia 

Lewy body dementia is a condition that's caused by abnormal deposits of a protein in your brain. The alpha-synuclein protein causes chemical changes in the brain that lead to cognitive decline and mood and behavior changes.

This condition is often mistaken for Parkinson's disease because both conditions share several common symptoms. Common symptoms of Lewy body dementia include visual hallucinations and confusion. 

Parkinson's Disease 

Parkinson's disease is a condition that progressively causes difficulty in movement in people living with it. Early signs of the condition include tremors.

As the disease progresses, your muscles become stiffer, and movement becomes more difficult. While the condition is primarily marked by difficulty with movement, it also causes a loss of cognitive function. 

Treatment for Neurodegenerative Diseases 

Unfortunately, there's currently no cure for neurodegenerative diseases. They are typically treated with a combination of medication and psychotherapy.

The exact combination and form of drugs depend on the form of neurodegenerative disease one has been diagnosed with.

Treatment for each form of the neurodegenerative disease varies. However, treatment typically focuses on alleviating symptoms of the condition.

Research Is Ongoing

Over the last few decades, cutting-edge research has made leaps and strides in developing new innovative medications for treating neurodegenerative diseases. For example, there is ongoing research into using immunotherapy to treat Alzheimer's disease symptoms.

Medications help manage the physical and mental symptoms of neurodegenerative diseases. Unfortunately, these diseases are progressive, and there are currently no medications that can help to slow down the progression of their symptoms. 

18 Sources
Verywell Mind uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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By Toketemu Ohwovoriole
Toketemu has been multimedia storyteller for the last four years. Her expertise focuses primarily on mental wellness and women’s health topics.