Is the sleep of sleepless subjects really of “bad quality”?
Clinical research has shown the existence of two main factors capable of influencing the perception of “bad sleep” in subjects suffering from insomnia. On the one hand, the difficulty of being able to recognize the signs that precede sleep and that push us to prepare for sleep, and on the other, the presence of erroneous beliefs on the idea of ”good sleep”.
Advertising message “Perception of sleep” means the ability of the individual to know how to identify his sleep, distinguishing it from a waking state and to be able to subjectively assess its quality. This perception appears to be altered in sleepless subjects and this is what makes these factors play an important role in the maintenance and genesis of insomnia (Giganti et al., 2016). Let’s take a closer look.
A first factor that influences the perception that an individual has of their quality of sleep is the ability to know how to recognize the onset of sleep on the basis of some physical signals such as reduced motor activity, closing the eyelids, burning eyes, drowsiness, the difficulty of maintaining concentration and the gradual modification of brain activity which gradually takes on the characteristics of REM sleep (Salzarulo, 2003).
In sleepless subjects, however, these signals are not taken into account when going to bed while external signals are privileged, such as the time (Giganti et al., 2014). The consequence of relying exclusively on the time to understand if it is time to go to bed, without taking into account one’s circadian typology (i.e. the natural propensity to sleep that differs from person to person), is that the individual could go to bed at an early schedule without being able to sleep. The non-occurrence of sleep in a short time, could then lead the individual to ruminate on the daily worries and the possible negative consequences produced by the “bad sleep” (Van Egeren et al., 1983) creating a vicious circle that keeps you awake. Rumination,
Another factor that influences the perception of the quality of one’s sleep is the psychological one linked to ideas and beliefs, which in turn are modulated by cultural, social and personal experiences (Giganti et al., 2016).
A first belief believes that the optimal duration of sleep, necessary to sustain good functioning during the day, is eight hours per night (Morini et al., 2002). However, this view does not take into account numerous factors including inter-individual differences relating to the type of dormitory and physiological changes due to age. With aging, for example, sleep and awakening times tend to be brought forward and the number of people sleeping for shorter periods increases.
Another false belief is that one night of disturbed sleep is enough to produce negative diurnal consequences. In fact, research shows that physiological mechanisms normally allow to cope with episodic sleep loss without objective consequences (Harvey and Greenall, 2003).
Advertising message Another common idea is that good sleep quality should not present nocturnal awakenings (Bruck et al., 2015). In reality, nocturnal awakenings may be present but while in normal-dormitory individuals, taking 2-4 minutes of actual sleep to have the perception of having slept, the presence of nocturnal awakenings does not entail a perception of “poor sleep quality”, the situation is different for sleepless subjects, who need about 15 minutes of sleep to have the perception of having slept. The consequence, for the latter, is therefore to have a greater chance of experiencing the feeling of not having rested at all if there will be more consecutive awakenings separated by brief episodes of sleep (Knab and Engel, 1988).
Finally, it is useful to remember that these dysfunctional thoughts tend to be associated with counterproductive attitudes such as staying in bed forcing themselves to sleep which, if favored over time, induce the association between being in bed and a state of hyperactivation that makes it even more difficult falling asleep (Perlis et al, 1997).
In conclusion, these evidences demonstrate how insomniac subjects are less able, compared to normal-sleeping individuals, to discriminate sleep from wakefulness; they also show how insomniacs tend to perceive the duration of sleep shorter than the real one and how they overestimate the time of sleep by evaluating their “bad quality” sleep (Ohayon and Reynolds, 2009). Psychological and cognitive factors such as personality characteristics (Edinger et al., 2000), mood (Edinger et al., 2000) and memory (Perlis et al., 1997) also influence these perceptions.
Based on what has been analyzed, the treatment of insomnia should not focus on increasing total sleep time or reducing sleep latency but rather on the objective of modifying erroneous beliefs about sleep and the dysfunctional behaviors associated with it (Harvey, 2002).
In this regard, behavioral interventions that use techniques such as “sleep restriction” and “stimulus control” have proved useful both in order to make the sleepless person more aware of having slept, reducing the worries associated with sleep, both by improving the ability to detect body signals that indicate the onset of sleep (Giganti et al., 2014).