In a recent study published within the Journal of Sleep Research, researchers determined the predictors and effects of using intermittent morning alarms on sleep, cognition, cortisol awakening response (CAR), and mood.

Study: Is snoozing losing? Why intermittent morning alarms are used and the way they affect sleep, cognition, cortisol, and mood. Image Credit: Generated with DALL.E 3

Background

While ‘snoozing’ is a typical behavior amongst people throughout the globe, little is known about its causes and potential effects on a person’s physical, emotional, and cognitive health. Thus far, few studies have examined snoozing; nonetheless, evidence suggests that fragmented sleep as a consequence of snoozing may impact day by day life, similar to a weak CAR resulting in sleepiness and deficits in cognitive performance and mood.

Concerning the study

The present study was conducted in two parts.

The main target of Study 1 was to look at the characteristics of people who snooze and their reasons for snoozing. A complete of 1,732 individuals with a mean age of 34 years from Sweden, the USA, the UK, Finland, and Australia were included within the Study 1 cohort. About 66% of the participants were women, and 33% were men.

These individuals were surveyed on their sleeping and waking habits using an internet questionnaire. These data were analyzed to check snoozers with non-snoozers using t-tests and chi-square tests to evaluate the potential link between snoozing and the standard and duration of sleep.

Study 2 was a laboratory experiment conducted to know the consequences of snoozing on cortisol levels, mood, sleep architecture, and cognition post-waking up. This crossover study involved 31 habitual snoozers with a mean age of 27.5 years, 18 of whom were women.

Individuals with difficulty sleeping, insomnia symptoms, heavy snoring, or other physical or mental ailments were excluded from the study. All study participants slept within the laboratory for 3 nights wearing polysomnography gear.

Study participants were subjected to 2 waking conditions of snoozing or no snoozing. The experimental protocol was adjusted in response to their regular sleep and wake times.

Within the snoozing cycle, the participants were asked to set their alarms half-hour prior to their regular wake time, with three snooze events of 10 minutes each before waking. Within the no-snoozing condition, participants were asked to set their alarm at their regular waking time and weren’t permitted to snooze.

The participants’ saliva samples were collected after waking and after 40 minutes to measure their cortisol levels. Cognition was evaluated using Karolinska WakeApp (KWA) tests. The KWA test lasted a median of 13 minutes and tested the participants for arithmetic speed, Stroop, and episodic and dealing memory.

All study participants self-rated their sleepiness, performance, mood, and energy.

Study findings

In Study 1, 69% of participants reported snoozing their morning alarm sometimes, whereas about 60% fell asleep between the 2 alarms. A median of twenty-two minutes were spent snoozing, with each interval about eight minutes long.

Interestingly, the snoozers were about six years younger than the non-snoozers, and most were prone to be “evening types.” No significant difference was observed in sleep quality; nonetheless, those that snoozed were thrice more prone to feel drowsy upon waking up.

No gender-based differences were observed. Probably the most common reasons for snoozing were “feeling too drained to get up,” “wanting to get up slowly,” and “it feels good” amongst 25%, 17%, and 17% of the cohort, respectively.

In Study 2, no significant effect of snoozing was observed on self-rated mood, sleepiness, CAR, or sleep architecture. Nevertheless, a transient snoozing period may help reduce sleep inertia and barely improve cognition right after waking, because the participants within the no-snooze condition showed an inertia effect in all of the tests except the Stroop test in comparison with those within the snooze condition.

Snoozing was found to stop awakening from slow-wave sleep (SWS), as not one of the participants within the last half-hour of sleep within the snoozing condition had SWS as in comparison with 30% within the no-snooze condition.

Importantly, the Bayes aspects determined in the general study show various strengths of evidence.

Conclusions

The study findings provide novel insights into the usage of intermittent morning alarms and their effects on people’s overall well-being, with necessary implications for his or her work efficiency. Further research must include more representative samples, longer snooze times, and non-habitual snoozers.

It could even be interesting to analyze the effect of daylight, the long-term impact of snoozing, and the mechanisms underlying the observed effects to further improve our understanding of this behavior.