Do you think you’re smarter than the majority of the population? Have a sharper intellect than most? Check out these indicators to gauge whether you’re on the smarter side of the spectrum or if it might be time to hit the books again.

1. You’re a Lefty

Southpaws rejoice! Left-handedness used to be considered a sign you were destined to be a criminal, but a new study links it to “divergent thinking,” which is a creative way to come up with new ideas from a challenge.

A study from 1995 found that left-handed men were better at thinking in different ways. That means they were better at things like joining two common items in creative ways to make a third and putting lists of words into as many different groups as possible.

2. You’re a Night Owl

Satoshi Kanazawa, an evolutionary scientist, did a study in 2009 that was released in the journal Personality and Individual Differences. He looked at the link between a person’s IQ when they were young and how they slept. The results showed that teens with higher IQs said they stayed up later and got up later during the week and on weekends.

In a 2006 study, researchers from Catholic University in Milan found that people who stay up late may be more likely to come up with unique and creative answers to problems than people who get up early. 

3. You’re Messy

University of Minnesota professor Kathleen Vohs says that the more chaotic you are, the smarter you are. In a study by Vohs that was released in Psychological Science, two groups were asked to come up with different ways to use Ping-Pong balls. One group worked in a crowded, messy place, while the other worked in a clean place. The messy group came up with a lot more interesting and creative ideas.

4. You’re the Oldest Kid in Your Family

A study of 250,000 Norwegians that was released in Science magazine found that the average IQ of the eldest child was 2.3 points better than that of the youngest child. Environment and how the family works are to blame, not genes. The first child gets the full attention of his or her parents. When No. 2 comes along, the bigger brother becomes a teacher for the younger sibling. This requires a lot of thinking and can make some firstborns smarter.

5. You’re Naturally Curious

Learning is enjoyable; the more you do it, the brighter you will become. According to research conducted at London’s Goldsmiths College, one of the most important factors in developing one’s mind is “how people invest their time and effort in their intellect” (i.e., by satisfying their natural inquisitiveness).

However, the desire to learn more is much more important than the actual amount of knowledge acquired. According to research published in the Journal of Individual Differences, people who scored higher on IQ tests as children tended to be more intellectually inquisitive and receptive to new ideas as adults.

In addition, a study conducted by psychologists at Georgia Tech found that people with a high level of curiosity are more open to uncertainty.

6. You Use Drugs (But Not How You Think)

A 2012 investigation of almost 6,000 British citizens born in 1958 discovered an association between high IQ in early life and drug abuse in later years.

However, their results show that a high IQ in infancy may lead to the adoption of behaviors that are potentially hazardous to health (i.e., excessive alcohol consumption and drug use) in adulthood, which contradicts the majority of research on the link between childhood IQ and later health.

7. You Drink Alcohol

A different study found that British and American people with higher childhood IQ scores consumed more alcohol as adults.

A 2021 Scandinavian Journal of Public Health Research of Norwegian males in their 20s indicated a favorable link between drinking and IQ in their late 20s but not early 20s.  

8. You’re Funny

Four hundred psychology students participated in intelligence research published in 2011 in the journal Intelligence. The exams assessed participants’ verbal and abstract thinking skills.

They were then asked to provide captions for various New Yorker cartoons evaluated by a separate panel of judges.

Students with higher IQs were seen as more humorous.

9. You Talk to Yourself

It’s the exact opposite of an indication that you’re going insane. According to research by Paloma Mari-Beffa and Alexander Kirkham of Bangor University, talking aloud to oneself has been shown to increase self-control. Participants in the research were given a list of instructions and asked to read them quietly or aloud. The reading comprehension and performance of those who read aloud improved significantly.

Of course, there’s always the flipside and maybe you’re not quite as smart as you thought you were. Here are three signs that may mean you’re on the other end of the scale.

1. You’re Not Curious

A lack of interest is characteristic of those with poor intellect since it prevents them from learning anything new. They have the bare minimum of knowledge necessary to survive. They don’t appear intellectually curious or discontent with where they are.

2. You’re Closed-Minded

People with low intellect tend to be trapped in their ways because they resist learning and growing from new experiences. People with narrow worldviews prefer to look for evidence that supports their current worldviews. For this reason, they are totally incapable of acquiring any new knowledge.

3. You Think in Black-And-White Terms

People with low IQs are experts at seeing things in stark black and white. They cannot identify any middle ground in their thinking, focusing instead on extremes. Too frequently, reality defies easy interpretation into binary categories.