Originally published 2016-08-17.
The Minds JournalAre people who sleep late smarter or more creative than early risers? The honest answer is: only a little, sometimes, and not because they sleep late. A few studies have found small links between an evening preference and higher scores on certain reasoning or creativity tests. None of them shows that staying in bed makes anyone brighter, and the same research finds that night owls often pay a price at school and work, where days start early.
If you are a natural night person, there is no need to feel lazy about it. Your body clock is largely built in. But the viral claim that "science says late sleepers are geniuses" stretches a handful of modest results much further than the data allow. Here is what the studies behind that claim actually found, and what is useful to take from them.
What a chronotype is and why it is not a choice
Sleep researchers use the word chronotype for a person's natural timing: when you tend to feel sleepy, when you wake without an alarm, and when you feel most alert. At one end are strong morning types, at the other strong evening types, and most people sit somewhere in the middle. A large 2007 survey of more than 55,000 people led by Till Roenneberg found that this trait is spread across the population in a bell-shaped curve rather than splitting people into two camps.
Chronotype is partly inherited. Genome-wide studies have linked dozens of gene variants to morning or evening preference, many of them near genes involved in sensing light and running the circadian clock. One study of 128,266 people in the UK Biobank (Jones and colleagues, 2016) identified several new regions tied to "morningness". Environment matters too: daylight, mealtimes, screens and school or work timetables can nudge the clock earlier or later.
Age has a strong effect. Young children tend to wake early, teenagers drift later, and many older adults shift back toward mornings. That is worth remembering when a study compares sleepy teenagers with alert ones, because a late schedule in adolescence is normal biology, not a personality flaw.
The Madrid study: higher reasoning scores, lower grades
The study most often quoted in "night owls are smarter" stories came from a research team in Madrid. As Smithsonian Magazine reported in 2013, the researchers sorted about 1,000 teenagers by their sleep habits and the time of day they felt sharpest. Roughly a quarter were morning types, about 32 percent were evening types, and the rest were in between.
The evening-type teens tended to do better on tests of inductive reasoning, the ability to spot a rule or pattern from examples. Inductive reasoning is often used as a stand-in for general intelligence. That is the part that went viral.
The part that rarely made it into the headlines is that the same night-oriented students had school grades that were, on average, about 8 percent lower than those of morning types. The likely explanation is simple: lessons and exams start early, when evening types are at their least alert. So the study does not show that late sleepers are better students. It shows a small edge on one kind of test, alongside a real disadvantage in the setting where most teenagers are judged.
The creativity research from Italy
The second study behind the claim is by Marina Giampietro and Guido Cavallera, published in 2007 in the journal Personality and Individual Differences under the title "Morning and evening types and creative thinking". It looked at 120 people aged 19 to 76.
The researchers reported that an evening disposition was associated with one particular skill: using divergent thinking on visual material, meaning coming up with many varied ideas from shapes or images. They described their work as exploratory and called for more research. It did not test whether sleeping late causes creativity, and it did not find that evening people beat morning people on every creative task.
A wider look at the evidence points the same way. A meta-analysis by Franzis Preckel and colleagues in 2011 found a small positive association between evening preference and intelligence scores, and a later analysis of UK Biobank data reported something similar. "Small" is the key word: knowing someone's bedtime tells you almost nothing about how clever or inventive that particular person is.
Myths that came with the headline
"Sleeping in makes you smarter"
No study found this. The research compares people with different natural rhythms. A morning person who forces themselves to stay up late gains nothing, and a night person who sleeps until noon after going to bed at 4 a.m. is simply getting their sleep at a different time.
"Early risers are boring and conventional"
Some of the older articles described morning people as merely productive and night people as the true inventors. That is a stereotype, not a finding. Morning types in these studies also produced creative work, and many famous writers and scientists kept strict early routines.
"The Huffington Post published research"
Earlier versions of this story said the findings were "published in the Huffington Post". A news site reports on research; it does not publish the peer-reviewed study. When you see a claim like this, look for the journal name and the authors. In this case they are the Madrid team and the Giampietro and Cavallera paper above.
"Night owls have an evolutionary advantage in intelligence"
One theory, associated with psychologist Satoshi Kanazawa, suggests that more intelligent people are drawn to "evolutionarily novel" habits such as staying up at night. It is an interesting idea but a speculative one, and Kanazawa's wider work has been heavily criticised by other researchers for its methods and interpretations. It is best treated as a hypothesis, not as settled science.
The downside of being out of sync
The real issue for many night owls is not intelligence but mismatch. When your body wants to sleep at 1 a.m. and your alarm goes off at 6:30, you build up a sleep debt during the week and try to repay it at weekends. Researchers have linked a strong evening chronotype with higher rates of low mood and depression, and evening types are over-represented among people with ADHD and delayed sleep phase disorder. These are associations, not proof that late sleep causes these conditions, but they are a reason to take chronic tiredness seriously.
The Madrid grades result is a good example of the same problem. The students were not less able. They were tested at the wrong time of day for their biology.
Practical takeaways for night owls
- Protect the total, not the timing. What matters most for mood, memory and health is getting enough regular sleep. Adults generally need around seven or more hours.
- Use your peak hours. If you can choose, put demanding or creative work in the late afternoon or evening, when you feel sharpest, and routine tasks in the morning.
- Get morning light. Daylight soon after waking is one of the strongest signals that moves the body clock earlier, which helps if your schedule is fixed.
- Keep weekends close to weekdays. A huge lie-in on Sunday can make Monday morning even harder.
- Talk to a doctor if you cannot fall asleep at a reasonable hour even when you try, or if daytime sleepiness is affecting your work, driving or mood.
The fair conclusion
Being a night owl is not a sign of laziness, and it is not a badge of genius either. The research describes small average differences between groups, mostly measured on specific tests, plus a clear cost when late sleepers are forced into early schedules. The most useful message is a modest one: know your rhythm, get enough sleep, and where you have the freedom, arrange your day around the hours when your mind works best.
The image above is credited to The Minds Journal. This story first circulated online through Complex, Elite Daily and Ideaspots.
Sources: Smithsonian Magazine: Night owl and early bird teens think differently (2013); Giampietro and Cavallera (2007), Personality and Individual Differences 42: 453-463 (summary); Università Cattolica record of the Giampietro study; Wikipedia: Chronotype; Wikipedia: Satoshi Kanazawa.
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