“Your brain – every brain – is a work in progress. It is ‘plastic.’ From the day we’re born to the day we die, it continuously revises and remodels, improving or slowly declining, as a function of how we use it.” – Michael Merzenich, Ph.D., co-inventor of the cochlear implant and author of Soft-wired: How the New Science of Brain Plasticity Can Change Your Life

In life, taking care of both our mental and physical health is important. However, in the modern world, a lot of us don’t spend nearly enough time giving our brains and bodies a proper work out. Instead, we spend much of our time watching TV, scrolling through social media, and in general, glued to our screens. In fact, a first-quarter 2018 Nielsen Total Audience Report found that nearly half an adults’ day is spent consuming and interacting with media. Pretty scary stuff.

Obviously, we all could make some changes, like sacrificing an hour or two of entertainment in order to get our sweat on at the gym. According to a study conducted by researchers at the University of British Columbia in Canada, regular aerobic exercise increases the volume of the hippocampus, a part of the brain that helps with memory and learning. Exercise also helps reduce depression and anxiety symptoms, which allows your brain to function better.

So, you can see how exercise helps the brain perform better, but mental training is equally important. Brain activities and riddles (such as the quizzes below) have been proven to:

  • Increase cognitive abilities
  • Improve short-term (working) memory
  • Increase attention span
  • Reduce emotional reactivity
  • Increase processing speed (the transferring of sensory information into intelligence)

Riddles and brain teasers can help to keep your brain young and sharpen your cognitive skills. The following riddles will keep you guessing, so make sure you pay attention to the details! (You’ll find the answers at the end of the article).

Here are 5 short quizzes that will make you think twice:

  1. The bat and the ball riddle

A bat and a ball cost $1.10 altogether. The ball costs $1 less than the bat. How much does the ball cost?

  1. The 7 candles puzzle

You have a big round cake in front of you with 7 candles along the cake’s edges. You need to blow out all of the candles, placed around the cake in a circle. Keep in mind that once you blow out one candle, the candles near it will go out as well. However, if you blow out an extinguished candle, it will reignite. So if you blow on a candle, as well as the candles closest to it, they will extinguish or reignite. The question is: how can you blow out all the candles with the fewest blows?

Hint: Remember that blowing on the same candle twice will cause it to reignite.

  1. Apples and oranges brain buster

You have 3 boxes in front of you. One contains oranges, one has apples, and one has both oranges and apples. The first box has the label “apples,” the second one is labeled “oranges,” and the third one is named “apples and oranges.” Unfortunately, all the boxes are labeled incorrectly, and it’s up to you to fix them. You can’t look in any boxes, but you can ask for a sample from each box.

What is the fewest number of samples you need to ask for in order to accurately label the boxes?

  1. The hourglass brain teaser

You have two hourglasses in front of you. One hourglass measures 7 minutes and the other measures 4 minutes. How can you time 9 minutes by using only these two hourglasses?

  1. One light, three switches

You are in a room with three switches. One of these controls a lightbulb inside a closet attached to the room. You know the lightbulb is off. You can flip the switches however you want, but once you open the closet door, you can’t flick the switches any more.

So, which switch controls the lightbulb?

Answers to the Quizzes:

  1. 5 cents. The bat costs $1.05, so if you add the cost of the ball, you’ll get $1.10.
  2. Seven. If you blow on each candle one time, starting from the first and continuing around the circle, you’ll blow them all out. Of course, some candles will become relit, but they will eventually extinguish from an adjacent blow.
  3. One. You only need to ask for a sample from the box labeled “apples and oranges.” If you get an apple, the box could contain only apples, or both apples and oranges. However, since the label is wrong, you know that it only contains apples. Then, move to the box labeled “oranges.” Since the label is incorrect, you know the box contains apples and oranges. Finally, the box labeled “apples and oranges” contains just oranges.
  4. Start both hourglasses at the same time. As the 4 minute hourglass runs out, turn it over so it can start again. As the 7 minute one runs out, turn it over and let it start again. When the 4 minute hourglass runs out a second time, you know that 8 minutes have elapsed. Now, the 7 minute hourglass will have sand sitting at the bottom for one minute. Turn the seven minute one over again and wait for the minute to run out. Once this one runs out, 9 minutes will have elapsed.
  5. It could be any of the three. To find out, flip switch number one and wait for a few minutes. Then flip it back to its original position and immediately flip switch 2. Next, open the door and check the light. If it’s on, you know that switch 2 controls it. But if it’s off, then feel the lightbulb. If the bulb is hot, switch 1 controls it. But if it’s cold, then switch 3 (the one you didn’t touch) controls the light.

If you didn’t get the answers right, don’t worry. Practice makes perfect, so try doing a few brain quizzes per day to give your mind a workout!

Tips on Training your Brain

Going back to the quote at the beginning of the article, our brains have the ability to change and adapt throughout our lives based on the information we feed them. We can mold our brains just as we can shape our bodies. If you don’t feel particularly talented or smart in one field, you can always study and train your brain to absorb, retain, and utilize the information.

Within the last 20 years, scientists have made groundbreaking discoveries in regards to neuroplasticity, or the idea that our brains make new connections and pathways as we feed them new information. So, by stimulating and challenging the brain, we can become sharper, wiser, and mentally stronger!

If you’re wondering how exactly to train your brain, here are some tips straight from Harvard University:

Cover the basics: Eat a healthy, mostly unprocessed diet. Get quality sleep. Avoid smoking. Drink alcohol in moderation, and keep in touch with friends and family.

Get a physical exam once per year so you can stay on top of your health and rule out any major issues.

Challenge your brain. Do brain quizzes (like the ones above), learn a new skill, or take courses either online or in person.

Keep yourself happy: easier said than done, but it pays off immensely in the end. People who have a positive mindset have better health, in general.


Repeat what you have learned. If you took up a new hobby, practice it often so you learn to master it. If you do brain quizzes, make sure to engage in them at least several times per week. Finally, if you decided on taking a course, make sure you take tests regularly so that you can see what you’ve learned.

Stay organized. The key to becoming the master of your brain is to only use it when absolutely necessary. For example, if you find that you lose items around the house often, have a designated spot for them so you don’t have to waste valuable brain energy on locating them.

Final thoughts on These Quizzes that Will Make You Think Twice

The brain is the most complex organ in the entire body, and keeping it healthy requires a combination of tools and practices. In general, you’ll want to stay physically active, eat the right foods, drink plenty of water, practice positive thinking, have a good support network, and get enough sleep. That covers the basics.

Then, if you want to “level up,” you’ll want to utilize brain-training exercises such as brain quizzes, riddles, and games. You can look in your app store and find dozens of different brain games to play, as well as browse at your local bookstore if you prefer the old-school approach.

If you feel like your brain lives on autopilot most of the time, you can easily snap it out of this state by giving it a challenge. Allowing your brain to think differently will enable it to form new pathways and networks that encourage it to adapt and grow. So, pick up a puzzle in your spare time and have some fun!