Everyone wants to be smarter. If I could make a pill that improved your intelligence, I would be the world's first trillionaire. Since that is really hard and I'm kind of lazy, I've done the next best thing and compiled a list of activities that make you smarter. Most of these are based on real scientific research, and I have linked to the research papers wherever possible. Take up a few of these hobbies and reap the benefits of improved mental performance.
What is intelligence?
Before diving into the list of activities that can make you smarter, it is important to discuss the meaning of intelligence. There are a lot of possible definitions for "intelligence", and some are more appropriate than others in different situations. Something like IQ might be used for research because it is easy to quantify, but there are a lot of other forms of intelligence that can have meaningful benefits in your life even if that form of intelligence is not easy to measure.
As such, the list of activities that make you smarter could be much, much longer than the one given here, because obviously there are some activities that make you smarter about some specific subject. For example, if you take up gardening, you will probably learn a lot about plants. In fact, any hobby that results in you learning something could be said to "make you smarter", but that's not what this list is focused on.
For this list, I've chosen activities that have shown benefits in the more abstract areas of intelligence, such as problem solving, memory retention, and creativity. Any activity that challenges your brain is a good way to spend your time, but if you wanted a shortlist of things to do that to boost your brain power and help you in many different areas of life, check out the list that follows.
1. Play an instrument
Music is a mentally challenging hobby. It involves a wide range of skills including muscle control, interpreting symbols, and improvisation, so it really isn't a surprise that it has benefits for your brain. The research backs this up.
According to research published in 2011 by Brenda Hanna-Pladdy and Alicia MacKay, elderly individuals who played an instrument for 10 years or more showed better performance on a range of different cognitive ability tests than people who played less than 10 years. This suggests that taking up music as a lifelong hobby could help reduce the risk of cognitive decline in old age.
But the benefits of music aren't reserved for the elderly. Other research published in The Journal of Neuroscience showed differences in brain structure between musicians and non-musicians. In that research, the brains of musicians were shown to have more gray matter. What's interesting is that there was a correlation between gray matter and the amount of time spent playing, with non-musicians having the least gray matter and professionals having the most. This means that the music could be responsible for the differences in brain structure.
Gray matter is a type of brain tissue that is involved with decision making, self control, muscle control, sensory perception, speech, and memory, so it is safe to conclude that practicing a musical instrument regularly could potentially help in most or all of those areas of mental performance.
2. Read both fiction and nonfiction
If there is one activity most closely associated with intelligence, it is reading. But apart from the obvious fact that reading nonfiction books can make you smarter, there is also research suggesting that fiction also has benefits, and they are different than the benefits you get from nonfiction.
According to research that looked at brain activity while people read, fictional literature increases blood flow to parts of the brain that are responsible for paying attention to a task.
Another aspect of intelligence that can be improved by reading fiction is what psychologists refer to as "theory of mind". Theory of mind is the ability to recognize beliefs, desires, emotions, and knowledge of yourself or others, and the ability to understand that the beliefs, desires, emotions, and knowledge of other people can be different than your own. People with weak theory of mind have trouble predicting and understanding the actions of others because they have trouble understanding that the thought processes of others can be different than their own.
A groundbreaking study published in Science (paywall) in 2013 found that reading literary fiction causes a temporary increase in people's theory of mind, which means that reading fiction can put you more in touch with the beliefs and knowledge of other people and understand different points of view. Importantly, the effect was only seen when people read literary fiction. There was no such effect from popular fiction or nonfiction. So in addition to the factual knowledge you can get from nonfiction, you might gain some other intellectual benefits from adding in some of the classic works of fiction.
Just about everybody knows that exercise has enormous benefits for strength, endurance, and heart health. But a growing body of research is showing that it also has benefits for the brain.
According to multiple research studies published in recent years, frequent exercise can dramatically increase the amount of a protein called brain-derived neurotrophic factor (BDNF). BDNF helps neurons live longer and promotes the growth of new neurons. BDNF is especially active in the parts of the brain that are responsible for learning, memory, and higher-level thinking. In addition, it is directly involved in the storage of long term memory in the brain. All of this suggests that exercise has powerful benefits if you want to remember more of what you learn.
Frequent exercise has also been shown to slow the rate of cognitive decline later in life. It also improves neuroplasticity, which is a really fancy way of saying that the brain is more able to adapt to different situations.
In most of the research, the most benefit was seen with aerobic exercise like jogging or biking.
4. Learn a language
If you are like me, you probably started learning a foreign language in high school, then gave up as soon as you finished the class. In my case, I realized that as a native English speaker, I didn't really need a foreign language. But the scientific research shows many benefits to foreign language study even if you never really need the language.
Multiple studies have shown that learning a second language creates structural changes in the brain. In particular, it increases volume in the hippocampus. Scientists don't fully understand what the hippocampus even does, but it is generally agreed that it plays a role in remembering events that have occurred throughout your life. It is also known that the hippocampus is one of the first areas of the brain to deteriorate due to Alzheimer's and other forms of dementia, which might explain why people who speak more than one language develop Alzheimer's 4-5 years later than people who only speak one language.
In addition to the structural changes to the brain, learning a foreign language can also affect your thinking process. An interesting study from The University of Chicago found that people solving a problem using a foreign language do so with fewer cognitive biases than people solving the same problem using their native language. In other words, using a foreign language made them rely more on logic and less on emotion in their problem solving efforts.
5. Take notes and review them
Of all of the activities listed here, few are as effective as simply taking notes. There is a reason your teachers always urged you to take notes: because it works. But you probably don't need to read research papers to know that. Where most people come up short with their note taking efforts is when it comes time to actually review the notes, either because of a lack of time or loss of motivation.
This is where a tool like Lernabit is useful. Not only does it provide a method of taking notes and accessing them from anywhere, but it combines it with algorithms that help you efficiently remember the information. It also reminds you to review your notes to help you keep up the motivation to review every day.
Whether you use Lernabit or just pen and paper, the most important step when taking notes is to review them regularly. With persistence, you will remember so much more of what you learn.
Becoming a more intelligent and open minded person is not a one time event. It is an ongoing process that can benefit from adding in some new activities that make you smarter.