The brain is an organ that holds countless mysteries. Of all of them, sleep is one of the processes that has aroused the greatest curiosity since ancient times, where it was understood as a bridge between the earthly and the divine. As a door open to the beyond.

We spend between a third and a quarter of our existence entangled in its fine threads, giving way mainly during the night to the slumber that guides us to its most inhospitable territories. We all sleep, because it is a universal need to survive (and a pleasure for most).

However, many people complain about poor quality sleep, because they either find it hard to get it or they wake up many times during the night. There are also those who wake up earlier than expected, and all of them usually feel very tired.

This article deals with the consequences of insomnia on mental health , since it is known that commitment in this area is one of the most important indicators for the inference of psychological suffering. Let’s see it, then, in detail.

What is insomnia?

Insomnia is understood to be any alteration in the process of sleeping, both in its beginning (difficulty in accessing sleep), and in its continuation (constant interruptions) and/or its end (waking up too early); which limits the quality of life and substantially interferes with daily activity.

Three basic dimensions could be distinguished in this regard: 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 long enough 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 performed by the central nervous system (CNS) is observed, while in the former (which extends over 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 way (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 areas. It is important to note that one third of people recognize occasional sleeping problems, and 10% meet the criteria for a diagnosis of insomnia. As we can see, this is not an uncommon situation, since a significant percentage of the general population identifies with it.

Let us now look at the concrete impact of insomnia on psychological health, by bringing together the seven most important consequences that can result from it. When one of them occurs, it can be interesting to visit a health specialist.

Main effects of insomnia on mental health

The relationship between insomnia and mental health is two-way: when one is affected the other is also affected, regardless of which is considered to be the cause and which is the effect. These complications are sometimes serious, and in some cases even involve an objective risk to life. That is why the treatment of this problem is important, and should never be considered as a minor or accessory matter. We go into detail about all of this.

1. Emotional changes

One of the common consequences of poor quality sleep is mood fluctuation, and there is evidence that insomnia and difficulties in regulating emotion have common physiological bases .

Thus, poor sleep can be associated with depressive and anxious symptoms, as well as with significant irritability. In fact, today we know that those who suffer from a condition of this nature see its intensity aggravated when, in addition, they have problems enjoying a good night’s sleep. Pain as a symptom deserves special mention: its presence alters sleep, while insomnia promotes a reduction in the algic threshold (becoming a much more intense and difficult to control experience).

On a process level, it is known that people with insomnia tend to interpret the adverse events they face more negatively, and also have difficulty extracting the positive aspects of daily experience. This problem is associated with the hyperfunction of the amygdala (limbic region responsible for processing different emotions) and the functional decrease in its connection with the prefrontal cortex , on which the cognitive mechanisms through which to deal with the inherent turbulence of life “depend”. All this facilitates a certain tendency to frustration, in cases where the vicissitudes of daily life cannot be resolved with the desired immediacy.

On the other hand, there are a few studies that suggest that the accumulation of sleepless nights substantially reduces the emotional intelligence assessed through self-reports. From this we could deduce a concrete erosion in the basic ability to identify, recognize and communicate what happens inside us ; as well as to infer the states of others when interacting with them. In any case, this would be a reversible effect over time, since a restorative rest would restore the previous level of “functioning” (given that intelligence is a relatively stable trait throughout life).

Finally, many studies indicate that people with insomnia may have altered cognitive decision-making and behavioral inhibition (both dependent on the prefrontal cortex); which would interact with depression, anxiety and/or irritability. The result implies the display of passive or impulsive patterns of action , which are associated with a greater probability of failure during the search for solutions to a problem. That is why it is never recommended to tackle issues of great importance under the influence of insomnia or adverse emotional states.

2. Memory problems

Interference in the memory domains is often a recurring complaint among those who have trouble sleeping. Most commonly, declarative memory, and especially the procedural subtype, is altered, which would limit the ability to recall events from the recent past.

In turn, a work memory erosion linked to insomnia (a function that allows the temporary storage of information for use during a particular task) has been described. In the latter case it is very frequent that difficulties arise in understanding a written/spoken text of a certain length , or in successfully carrying out activities that require storing information in the background.

REM sleep is a key physiological process for maintaining memory, as it optimizes the neural process by which we consolidate information in the long-term store and/or accessory and unusable data are removed. It is, therefore, basic to learning; from which it is understood that spending a night awake to study is often an inadequate and counterproductive strategy. Thus, a subject who has difficulty sleeping may report difficulties in acquiring new knowledge, as well as in applying it later (as in an exam, for example).

Memory problems and insomnia often occur together in older people , and may share some physiological basis (such as calcification of the pineal gland, which may also contribute to cortical dementias). Finally, the strong relationship between insomnia and mnesic decline may be due to the use of sedative/hypnotic psychodrugs (benzodiazepines, e.g.) prescribed for the treatment of sleep disorders, as we know that their prolonged or excessive administration precipitates harmful effects in such an area (anterograde amnesia or serious blockage by generating new memories).

  • You may be interested in: “Memory problems: their 3 types and the possible causes”

3. Attention problems

Along with memory, attention is the process that is most often compromised when a restful sleep becomes difficult. The orientation response to stimuli that abruptly interrupt the perceptive field is often fundamentally impaired, increasing response times (the person seems self-absorbed and slowed down). It has also been possible to observe a deterioration in alternating attention, that is, in the capacity to “change” focus when two tasks occur (one after the other) in short periods of time.

Finally, this decline can be generalized to the sustained and selective subtype . In this case, problems would be made explicit in order to maintain attentional resources during the development of a task whose long extension requires it, as well as to discriminate in a complex environment which of the stimuli are relevant to the objective being pursued and which are not. In this way, on seeing the person immersed in an environment saturated by various elements that compete for his or her attention, a sensation of overflow would arise (appreciable when managing the volume of information).

Attention deficits also imply that there is a greater risk of accidents , as there would be an increase in distractibility and a loss of reflexes. For this reason, those who are regular drivers of any vehicle have to take special care when suffering from insomnia.

4. Sexual problems

Insomnia can be related to deficits in the sexual sphere, especially in males. Most commonly, it is expressed at an erectile level, with problems in achieving a firm swelling of the penis to enable penetration. The most noticeable difficulty is found when the person lives with other additional clinical symptoms; such as sleep apnea, “delayed” circadian rhythm (falling asleep and waking up too late) or restless leg syndrome (pressing and distressing need to move the legs to relieve an apparent tension that builds up in them).

Certain hypotheses suggest as a possible cause for erectile dysfunction a notorious reduction of testosterone in the blood circulation , which has been evidenced among men who have difficulty falling asleep properly or who wake up many times throughout the night (especially in the second half).

There is evidence that this hormone’s production is increased during the beginning of sleep (reaching a peak in the first REM phase), and that its levels are higher while you are asleep than when you are awake. Insomnia would hinder its synthesis, which would affect the erection (since it is essential for this process), and would also contribute to the increase of cardiopathologies in this population (a risk that is accentuated in the case of insomniacs when drawing comparisons with those who rest well).

5. Hallucinations

Hallucinations are abnormal perceptions involving stimuli that are not in the perceptual field, in any sensory mode. There are many studies which point out that insomnia in extreme cases can occur with very diverse hallucinations, even in people without any kind of pathology.

Some of the most common are hypnagogic (in the process of wakefulness to sleep) and hypnopompic (in the transition from sleep to wakefulness), as well as those that occur in the context of sleep paralysis. All of them are much more frequent when one has not slept properly in the previous days .

In people with a psychotic disorder, such as schizophrenia, insomnia is considered a risk factor for the recurrence of an acute episode or for its occurrence. In fact, it is one of the main symptoms of the prodromal stage, which precedes the articulation of the “definitive” picture (and which extends over months or even years). Such insomnia would anticipate the onset of paranoid delusions in some patients, which could be explained by a rise in dopamine levels after the first sleepless night (a compensation mechanism to cushion the deficit in cognitive functions that usually occurs at this time).

  • You may be interested in: “Hallucinations: definition, causes, and symptoms”

6. Reduced vitality

The loss of vitality, at the end of which is fatigue, has as its basic cause (in the general population) poor quality sleep. It is a common circumstance, which coincides with the total percentage of people with punctual difficulty to sleep fully (between 20% and 40%, especially in women). The problem translates into high daytime sleepiness and loss of productivity, and is even associated with depressive feelings and impaired memory or attention (referred to above).

The fatigue associated with insomnia is associated with a perception of intense loss of energy, general weakness, a feeling of unease and erosion of performance in everyday tasks . Of all the problems that disturb the integrity of sleep or its structure, perhaps apnea is the one that most consistently triggers it (respiratory blockage that causes a series of brief micro-wakenings, which interrupt the active sleep cycle before reaching the reparative phases of REM).

7. Increased risk of Alzheimer’s

The relationship between insomnia and Alzheimer’s has been known since the 1990s, although it has been possible in the last decade to increase knowledge about this issue. Thanks to studies in neurophysiology, and with the invaluable help of neuroimaging techniques or the analysis of post-mortem brain tissue, we have come to the conclusion that a function of sleep consists of “cleaning” the residues of neuronal activity . Throughout the day, the fact of being awake implies a production of proteins in the central nervous system whose persistence is toxic, but which is “emptied” each time we sleep to avoid an excess or accumulation.

Of all these, it has been shown that the beta amyloid protein is undoubtedly the one with the greatest explanatory importance, given that it is one of the elementary anatomopathological bases of so frequent cortical dementia. Well, it has been corroborated that insomnia promotes its accumulation in the medium/long term, enhancing one of its most important physiological risk factors (according to the available evidence).

Bibliographic references:

  • Cunnington, D., Junge, M. and Fernando, A. (2013). Insomnia: Prevalence, consequences and effective treatment. The Medical journal of Australia, 199(8), 36-40.
  • Fernandez-Mendoza, J. and Vgontzas, A. (2013). Insomnia and Its Impact on Physical and Mental Health. Current psychiatry reports, 15(12), 418.
  • Marin, A., Franco, A., Vinaccia, S., Tobon, S. and Sandin, B. (2008). Sleep disorders, health and quality of life: A behavioural sleep medicine perspective. Suma Psicologica, 15(1), 57-64.