There are 5 sleep ‘types’, according to science – which one do you identify with?

How would you describe your sleep personality? Many people go straight to the sleep position they prefer – perhaps they’re a front sleeper or they can’t understand why anyone wouldn’t sleep curled over in a ball on their side. For others, it’s their chronotype: whether they’re a night owl or early riser. But according to new research, there may be another way of categorising our sleep behaviours, and each of which can be categorised by its effect on brain function and mental wellbeing.

Based on the results of a study published in the journal PLOS Biology, which analysed the brain scans, lifestyle and sleep quality data of more than 770 young adults, the five sleep types prove that sleeping well is about so much more than when you go to bed and how many times you wake up during the night.  

The study assessed the participants’ sleep using the Pittsburgh Sleep Quality Index, a way of measuring sleep quality that relies on factors such as satisfaction upon waking, the time it takes to fall asleep, sleep duration and the use of sleep aids. Other factors taken into consideration included the participants’ performance in cognitive tasks, personality traits and emotional states.

The five types of sleepers the researchers identified as a result were as follows:

1. Poor sleepers

People in this group were your classic ‘bad’ sleepers – they had plenty of sleep disturbances, a lower sleep satisfaction than their peers and they found it took them longer to fall asleep than average. These people also had worse mental health, with many showing symptoms of depression, anxiety and stress.

The researchers found that the brain scans of the people in this group also showed decreased connectivity between regions of the brain responsible for self-reflection and attention – indicating a possible inability to switch between inner and outer worlds, the scientists said. While you might think this could be driving the mental health issues (this could mean these types of people spend a lot of time ruminating on their thoughts and feelings, for example), the researchers found that resilient sleepers (more on them later) shared the mental health struggles but not the sleep problems, suggesting the brain patterns may be directly related to sleep.

2. Resilient sleepers

As mentioned above, resilient sleepers exhibited similar mental health symptoms to the first group – particularly related to inattention – but slept well despite their symptoms. Because their brains lacked the decreased connectivity of the first group, the researchers suggested this may explain the difference between those who can sleep well and those who can’t. 

However, the resilient sleepers still reported some kind of daytime impairment (eg feeling tired and sleepy during the day), suggesting their sleep still isn’t optimum. 

3. Sleep aid users

Sleep aid users, as you might expect, are those who rely on sleep aids, ranging from prescription medication to calming teas specifically marketed as being able to aid sleep. Interestingly, this group of sleepers were also found to have strong relationships with those around them – a finding the scientists suggested could be due to the impact of the sleep aids on mood or wellbeing, or simply because the sleep aids were helping their mental health by giving them good quality rest.

However, it’s worth noting that these types of sleepers performed worse on visual memory and emotional recognition tasks. Again, the researchers suggested this could be the impact of the sleep aids on daytime functioning.

4. Short sleepers

Short sleepers are those who get less than seven hours of sleep a night – the minimum amount experts recommend for overall wellbeing. Those in this group also had worse accuracy and longer reaction times on cognitive tests that measured social skills, language and emotional processing, as well as increased connectivity across brain networks. Interestingly, this is a phenomenon research has previously linked to sleep deprivation – suggesting it’s a direct result of the short sleep. 

5. Disturbed sleepers

The fifth and final sleep group the researchers identified were disturbed sleepers, whose sleep was often disrupted by frequent nighttime awakenings.

Both short sleepers and disturbed sleepers had increased aggression, while disturbed sleepers also had worse language processing and working memory, which could be a direct result of a lack of deep sleep caused by a fragmented sleep pattern. People in this group also tended to have symptoms of poor mental health.

What does all of this mean?

While not all of us will fit into these five categories – for example, if you sleep well on a regular basis and have generally good mental health – this study suggests that how well we sleep and the impact our sleep has on our wellbeing is fuelled by a variety of factors, including the way our brains work.

It’s a reminder that one-size-fits-all sleep advice doesn’t necessarily work; some people may be at greater risk of mental health issues after a night of poor sleep, while others may be able to get through without much bother.

More research is needed to identify exactly whether poor mental health is driving poor sleep or whether sleep is to blame for poor mental health (this study identifies associations between traits, not causational relationships), but either way, it’s a sign of just how interlinked these two parts of our health are. 

Images: Getty