Napping which is common among many people, regardless of health condition has generated some discussions regarding its value. Its complexity has attracted the interest of several doctors; psychologists and other scholars who have aimed to ascertain causes of napping as well as its impact on the cognition. Napping is prevalent especially among older individuals. Against this backdrop, this paper critically analyzes napping by assessing the benefits and drawbacks of napping and its possible impact on cognition.
Discussion
Causes of Napping
Although the exact reasons for napping have not been fully understood, Stickgold and Walker (2009) support the view held by other scholars that genetic, molecular and psychological processes take place during sleeping.
Since many studies have reported frequent incidence of napping among older than young adults, it is thought that the prevalence of napping among adults increases with age. Several factors have been linked to napping, such as recuperative need or prophylactic strategies that are manifested before or after loss of sleep, as well as appetitive need (Ficca et al, 2010).
Stickgold and Walker (2009) indentified three types of napping in work related environment: a) operational napping which is during working hours; b) prophylactic napping due to sleep deprivation anticipation; and c) compensatory napping due to sleep deprivation (Stickgold & Walker, 2009).
These factors can be attributed to napping in work places. Among the older, Ficca et al. (2010) hypothesized that daytime napping can be attributed to age related reasons, disturbed or inadequate night sleep, lifestyle factors or psychiatric and co-morbid illness. However, they did point out that evidence supporting the direct contribution of these factors is inconclusive, since napping and the aforementioned factors could have bi-directional causality effect.
Benefits of Napping
Napping is a prevalent phenomenon in all walks of life. Although the benefits of napping have not been conclusively documented, psychologists argue that frequent napping has many unprecedented benefits. Studies have revealed that people who nap frequently are likely to have more benefits than those who rarely nap.
According to Kerkholf et al. (2011), a nap of 7-10 minutes increases alertness because it permits rapid inhibition dissipation in weak active cells that cause sleep switch. This phenomenon is where the brain cells responsible for wakefullnes inhibit cells that cause sleep and vice versa. Napping therefore, has been known to cause rapid inhibition of sleeeping cells thus causing alertness.
Kerkholf et al.(2009) futher assert that napping are useful preventive and operational strategies which when used prophylactically, can incresd performance and alertness during prolonged wakefulness subsequent periods. Stickgold and Walker (2009) hold that prophylactic napping taken due to sleep deprivation anticipation can potentially lead to increase work performance besides reducing subjective sleepiness.
Stickgold and Walker (2009) concurred that by replenishing body energy, napping increases alertness levels thus increasing task performance and decision making capability. Kerkholf et al. further asserted that napping can be a perfect way to release stress and pent-up emotion; by taking a nap, individuals forget their worries and might wake up with fresh minds relieved of stress.
Napping can lead to improve health. By relaxing body functioning, it can help improve heart and hormonal functioning, as speed up cell repair, which is another way to rejuvenate the body (Stickgold & Walker, 2009).
As regarding napping impact on work performance, Stickgold and Walker (2009) argue that napping may reduce continuous wakefulness periods and the total hours a person is awake after a work period schedule. This, they argue, can be used effectively to maintain an optimal level of alertness and subsequent performance (Stickgold & Walker, 2009).
It is worth noting that the benefits of napping are diverse and depends among several factors which include the nap duration its frequency. However, there is no clear correlation that longer and frequent naps are beneficial while shorter ones are have negative effects.
Impact of Napping on Cognition
Researchers are continuously proving that napping improves memory. In a study carried out on children’s abstraction of general concepts, it was found out that infants who napped frequently were better able to generalize abstract rules in artificial languages (Lau et al 2011). However among preschoolers, increased napping has shown discrepancies with regard to cognition.
In a study conducted by Lam et al. (2011) that investigated the effects of napping on cognition function among preschoolers, it was found out that frequent napping led to a decrease in performance on neuro-cognitive tests.
Lam et al. (2011) concluded that, among preschoolers neuro-cognitive performance is facilitated by greater nighttime sleep, whereas daytime napping leads to alertness control problems. However, they noted that, these findings including the possibility that reduced napping may lead to improved cognitive development, cannot be generalized without conclusive evidence from controlled clinical trials.
In another study conducted by Lau et al. (2010) to determine the effects of napping on relational and direct associative memory, it was found out that people who nap have better direct associative and relational memory. Relational memory is the ability to associate between items learned separately.
These findings are supported by Lam et al.’s (2011) argument regarding the effects of napping on declarative and procedural memory which posited that, besides favoring procedural motor learning, procedural memory performance is dependent on nap duration (Lam et al. 2011).
Another study showed that a 60-90 midday nap is substantially beneficial to the consolidation of motor memory (Lau et al, 2010). However, the effect of napping on motor performance is dependent on napping frequency especially in terms of habitualness, since habitual napping consolidates motor learning (Milner et al. 2006). Several studies have been undertaken to study the effects of napping on declarative memory, and all seems to come to a conclusion that napping improves declarative memory performance (Lau et al. 2010).
To fully comprehend the impact of napping on cognition, several studies have investigated daytime sleeping patterns in children with developmental delays, autism and typical development.
For example, Schwichtenberg et al. (2011) revealed that children with developmental delays and those with typical development napped more often when compared to those with autism, who napped for shorter periods and less often. They argued that the paradigm change from biphasic to monobasic sleep often reflects neurodevelopment changes, daytime schedules, and physiological maturation.
Disadvantages of Napping
Although napping seems to have more benefits than disadvantages, studies have documented some drawbacks of napping that cannot be neglected. According to Ficca et al. (2010), napping is associated with high mortality risks, cognitive impairment, and high risks of cardiovascular heart diseases among the adults.
Napping has also been known to cause sleep inertia which is the disorientation or grogginess that comes as a result of awakening from sleep. Although sleep inertias are brief, lasting only for few minuts, it can have detrimental effects to people who work after napping spells. Stickgold and Walker (2009) assert that can negatively influence work performances for several minutes.
Although the probable impact that daytime napping would have on nighttime sleep have not been well documented, researchers have assumed that daytime sleeping may reduce homoeostatic sleep surge at night, which may in turn, result in reduced sleep efficiency and nighttime wakefulness. Stickgold and Walker point that this might lead to tiredness the following day (Stickgold & Walker, 2009). Individuals, who nap, therefore might have the quality and length of their night sleep affected.
Conclusion
Napping has been found to have many unprecedented benefits. Nonetheless other researchers have been of the view that napping has some drawbacks because it causes sleep disorders and instability in individual’s internal clock. Many researchers, however, concur that shorter naps are beneficial while longer and frequent ones have negative effects.
Others have shown that frequent napping potentially leads to cognitive impairment, high mortality risk and cardiovascular heart diseases (Ficca et al. 2010). Researchers have pointed out that, although napping can lead improve alertness, it can result to sleep deprivations at night. Regarding napping impact on cognition; study findings have been inconsistent and contradictory.
Although many studies seem to affirm that napping improves relational and associative memory, as well as abstraction of general concepts, other studies have shown that napping decreases neuro-cognitive tests especially among preschoolers. Many studies, however seem to concur that midday napping have more benefits and thus should be encouraged.
References
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