Neurodegenerative Disorders And Sleep Disorders

Neurodegenerative disorders are conditions in which the neurons of the central nervous system stop working or slowly die, causing various neurological signs and symptoms.

These conditions get progressively worse over time and are incurable. They can be manifested by a genetic component, a tumor or a stroke. Also, these diseases are more common in people who drink a lot of alcohol or who are exposed to certain viruses and toxins.

Sleep disturbances can also affect the manifestation of neurodegenerative diseases. A study from the University of Toronto has shown that REM sleep disorders can be an early sign of neurological disorders.

To dream

Since the 1960s, scientists have argued that dreams occur in the REM phase and that the brainstem is an important area to control them. This part of the brain communicates with the hypothalamus to make the transition from waking up to sleeping and vice versa.

Thus, the glutamatergic SubC cells (which regulate the transition between REM sleep and non-REM sleep) start a chain reaction. These cells owe their name to the brain region to which they belong: the subcoeruleus nucleus or SubC.

The response triggers the release of the GABA neurotransmitter, which simultaneously reduces activity in the hypothalamus and brainstem. GABA neurons are responsible for controlling REM sleep and especially muscle paralysis during deep sleep.

When these cells begin to activate, there is a rapid transition to REM sleep. The brainstem sends signals so that the muscles relax and the limbs do not move. With this in mind, researchers have attempted to analyze REM sleep disorders such as cataplexy, narcolepsy, and REM sleep behavior disorder.

REM sleep behavior disorder

People who suffer from REM sleep behavior disorder move their limbs or even get out of bed while still dreaming. Some patients may even talk or yell.

Doctors believe that this pathology makes patients a danger to themselves or others. Sometimes the negative consequences, such as self-mutilation or the person they sleep with, are warning signs for a diagnosis. The good news is that REM sleep behavior disorder is usually treatable.

Sleep Phases and REM Sleep Behavior Disorder

Sleep includes several stages:

• waking
• REM sleep
• non-REM sleep

Many characteristics define each stage. To understand REM sleep behavior disorder, it is important to know what is happening during this stage. During this stage, the brain’s electrical activity is similar to that of your brain when you’re awake.

Although neurons in the brain function in the same way during REM as they do when awake, REM sleep involves temporary muscle paralysis.

In some sleep disorders, such as narcolepsy, parasomnia or the REM sleep behavior disorder, there is almost no difference between the different stages. Experts believe that the “neurological barriers” separating the different stages of sleep do not function properly, although the cause of these phenomena is not yet clear.

Therefore, most people are unable to move their bodies even when they have vivid dreams. However, people with REM sleep disorder lack muscle paralysis, so they can move their bodies while having violent dreams.

REM sleep disorders and their influence on neurodegenerative disorders

Researchers have made a very interesting discovery: REM sleep disorders are related to several neurodegenerative disorders that manifest in the elderly. These findings suggest that the neurodegenerative processes initially affect the REM sleep circuits and, more specifically, the SubC neurons.

They also noted that more than 80% of people who suffer from REM sleep behavior disorders eventually develop synucleinopathies, such as Parkinson’s disease and Lewy body dementia (LBD). This research suggests that sleep disturbances may be an early sign of neurodegenerative diseases that can manifest 15 years later.

It is also worth noting that both Parkinson’s disease and LBD are related to an abnormal intraneuronal accumulation of alpha-synuclein proteins. Therefore, researchers expect that the study of these proteins will shed light on which neuroprotective therapies can prevent the development of neurodegenerative diseases.

Also, experts argue that as with cancer patients, diagnosis for REM sleep disorders can lead to preventive measures to maintain neuronal health before more serious neurological disorders begin to develop.