At night, trouble sleeping or falling asleep doesn't always come the same way. Sleep problems always produce discomfort and lack of energy and mood, but that doesn't mean that the causes of these symptoms are the same. In fact, there are different types of insomnia that affect us in a certain way depending on the nature of what generates this disturbance.
What is insomnia?
Insomnia is understood as any alteration in the process of sleeping at any stage. It includes difficulty to fall asleep, waking up often, and/or waking up too early. Sleep disorders limits the quality of life and substantially interferes with daily activity.
In this sense, three basic dimensions can be distinguished: duration (total time spent asleep, for which there is great variability in terms of inter-individual differences), continuity (which is equivalent to the persistence of the process over a sufficient time to obtain benefits) and depth (associated with physiology and neural activation). Either of these can be acutely compromised at some point in the life cycle.
Roughly speaking, sleep tends to be divided into two distinct stages: REM and non-REM (nREM). The latter involves a series of phases (from 1 to 4) in which a progressive slowing down of the activity of the central nervous system (CNS) is observed, while in the former (which lasts 25% of the time) an increase or electrical hyperactivation similar to wakefulness (with eye movements) would be observed. Both are alternated in cycles of 90 minutes throughout the night, in which the REM phase is extended, and are necessary for the relevant neural rest to take place.
The three forms of insomnia that have been cited represent, in their most intimate nature, a difficulty in accessing REM sleep in a relevant manner (especially when it becomes difficult to stay asleep for the time required to complete the successive cycles). As the situation is prolonged, a myriad of complications arise in the physical, cognitive and emotional spheres.
It is important to note that one third of people report specific sleeping disorders, and 10% meet the criteria for the diagnosis of insomnia. As we can see, this is not an uncommon situation, since a significant percentage of the general population identifies with it.
In this article we will see what the types of insomnia exist, what are their effects and how they develop.
Types of Insomnia
There is no single criterion for classifying types of insomnia, but different parameters are used to classify them. This means that these sleep disorders have different dimensions and that each of them does not describe all the characteristics of the insomnia a person suffers from. For example, intrinsic type insomnia may be long term in some people, but it is short term in others.
Insomnia can be classified on the basis of its causes:
1. Intrinsic sleep disorders
Cases in which the cause of the problem of adequate sleep can be explained by a specific alteration in the functioning of the brain belong to this category. For example, if there has been a brain injury, there may be problems in getting or maintaining sleep. The same is true for certain disorders, such as restless leg syndrome.
2. Extrinsic sleep disorders
Extrinsic insomnia occurs when the problem can be explained by the dynamics of interaction with the environment. For example, work burnout and disruption of work schedules can generate insomnia, and the same is generally true of lack of sleep hygiene or consumption of stimulants.
Sleep problems can also be differentiated according to their severity:
3. Mild insomnia
When insomnia only affects the daily routine and the degree of health in a very superficial and transitory way, it can be considered mild. For example, it takes half an hour longer than normal to fall asleep for about three days.
4. Moderate insomnia
In moderate insomnia there are routines and habits that are being affected by this problem, and in the same way health is compromised by tiredness, discomfort and concentration problems.
5. Severe insomnia
In this type of insomnia, health is greatly affected, and so is the ability to adapt to an appropriate schedule. In addition to the symptoms of the previous type, there are also memory and vision problems (sometimes it is difficult to focus for a while), bad mood and a clear lack of energy that prevents individuals from carrying out important tasks.
Types of insomnia can also be classified by their duration:
Acute or transient
6. Chronic insomnia
When problems with falling asleep or staying asleep last longer than about 5 or 6 months, it is considered chronic insomnia. This type of problem is difficult to correct, as it takes a long time to become "entrenched" in a person's routine and the circadian rhythm has changed and is difficult to alter.
7. Acute, or transient, insomnia
Some events or extreme stress can cause a person to experience insomnia for a few days. The problem is considered temporary if the symptoms do not last more than 4 weeks.
8. Short-term insomnia
This category includes cases where the duration of the problem exceeds one month but disappears before it can be considered chronic.
Considering the qualitative differences between the symptoms of insomnia types, this sleep disorder can be also classified according to 3 main categories:
9. Sleep onset insomnia
In this type of insomnia, the problems appear at the time of falling asleep, so it takes a long time between going to bed and starting to sleep. However, once you have started to get real rest, there are no frequent awakenings.
10. Sleep-maintenance insomnia
In this kind of insomnia the problem is maintaining sleep, so the person will wake up many times throughout the night and therefore will not rest well, since it will not go through all phases of sleep or will do so rarely throughout the days.
11. Middle-of-the-night insomnia (early awakening)
People who suffer from this insomnia wake up much earlier than they should (for example, 3 hours after going to bed) and can no longer fall asleep, as they feel too active to go back to bed from the beginning.
12. Mixed insomnia
This category is a "catch-all" category that includes cases where characteristics of two or more types of insomnia occur consistently.
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