You can leave it to the know-it-all so many of us have encountered to prove that what you know doesn’t make you an intelligent person. In fact, what you know, which is based on the information you’ve accumulated through books, school, etc., is commonly referred to as crystallized intelligence. And it’s different from fluid intelligence, a less concrete form of intelligence, which is based less on memorization and more on abstract thinking, such as the ability to identify patterns, solve problems, and reason.

Intelligence is a complex thing, and it’s affected each day by what a person does. For example, a New York Times article from last year highlighted how more school districts in the U.S. are implementing programs that teach kids how to be emotionally intelligent. The idea is that children who are taught how to manage their emotions, such as learning how to calm down during a moment of anxiety, are better able to learn because their self-awareness allows them to focus on the task at hand.

All these little details make understanding intelligence much harder, and in the process, a lot of information gets misconstrued, especially during random conversations in which a person claims absolute knowledge. So, with that said, here are four things you may or may not have heard about intelligence.

Brain Games Won’t Make You More Intelligent

With increasing rates of Alzheimer’s disease and other forms of dementia, companies like Lumosity have branded themselves as the solution to an aging brain. The concept is simple: Play games that involve remembering words or putting shaped objects into place, and your memory and attention will benefit. Though this is true, there are misconceptions that the games will also improve overall intelligence. That’s just not true.

In two studies, one from last October and the other from January, researchers found that the games delivered on their promise of better memory, attention, and multitasking skills. But when it came to overall intelligence, both studies show the games failed to improve. In one of them, participants were given one of three tests, which ranged in difficulty; they were told to either remember a group of items while engaging in another task (a complex span task), to recall items in the order they were shown (a simple span task), or to search for specific items in a group (a visual search task). The researchers found that participants who completed the complex span tasks had improved their working memory; however, their fluid intelligence stayed the same.

More Smarts, More Mental Illness

If you’ve ever seen the 2001 biographical film A Beautiful Mind, starring Russell Crowe, and based on the life of Nobel Laureate in Economics John Nash, then you’ll remember the tragedy that was a famed mathematician who battled schizophrenia. David Foster Wallace, another intellectual famous for his writing, struggled with depression for over 20 years — he committed suicide in 2008. This trend of mental illness among intellectuals goes back to names such as Abraham Lincoln, Isaac Newton, and Ernest Hemingway.

Where does this connection come from? Studies on a gene responsible for encoding calcium-binding proteins, called neuronal calcium sensor-1 (NCS-1), have found that the gene is also responsible for synaptic plasticity, which is the strength of neural connections based on how active they are. Incidentally, studies have also shown that up-regulation of NCS-1 is associated with schizophrenia and bipolar disorder. This could suggest that stronger plasticity — more smarts — also means a higher chance of mental illness. In another study, from 2005, researchers found that people who performed better on math tests were also more likely to have bipolar disorder.

Those Who Sleep Late, Wake Up Late, Are More Intelligent

Study upon study upon study has spoken about the harms of being a night owl. Whether it’s the light from your computer or TV, or simply staying up late, being awake when your circadian rhythm says you should be sleeping interferes with a number of biological processes. In turn, a person’s risk of diabetes, cancer, and fertility problems increases.

But it’s not all bad for night owls; a study or two have shown that night owls may be more intelligent than their early-to-wake counterparts. One such study, from 2009, is based on the Savanna-IQ interaction hypothesis, which suggests that intelligent people are more likely to diverge from activities practiced throughout evolutionary history. To put it simply, the study suggested that, because so many societies are active during the day and sleep at night, people who became more active during the night may have been more intelligent. Meanwhile, a study from last year found that night owls scored higher on tests measuring inductive reasoning, which is considered a good indicator of general intelligence.

IQ Tests Are Pretty Bad At Measuring Intelligence

Bringing it back around to the complexity of intelligence, and the fact that there are so many areas of intelligence, it’s impractical to believe that an IQ test can accurately measure a person’s intelligence. A 2012 study from Canada supports this idea, saying that intelligence was actually determined by a person’s short-term memory, reasoning skills, and verbal ability, of which none are completely measured in an IQ test. According to the Daily Mail, study author Dr. Adrian Owen said that these factors were independent and “unrelated to one another, and you could be brilliant at one and awful at another.”

In an interview with Scientific American, psychologist W. Joel Schneider says that the effectiveness of an IQ test really depends on what’s being tested. If it’s learning ability, for example, he says the method “is poor because learning ability is confounded by learning opportunities, cultural differences, familial differences, and personality differences in conscientiousness and openness to learning.” When asked about global IQ, he said that although “a person who scores very low on a competently administered IQ test is likely to struggle in many domains,” An IQ test will likely “miss the mark in many individuals, in both directions.”

Though the relationship between all of these factors is close, and intertwined sometimes, these findings only highlight how complex the human brain is. Considering that IQ tests were created during a time when intelligence was a much different concept than we know it to be today, it might be time to do away with it, and to replace it with something better.