What I Learned: A Mind for Numbers by Barbra Oakley

I learned a lot from this book. Mostly how to learn. It’s not super math intensive but it’s not supposed to be. If you’re having trouble learning this book is definitely for you. I’ll be breaking this up into the main topics of the book including modes of the brain, memory, chunking, procrastination, and other information.

Modes of the brain

When doing problems or learning new concepts. Your brain has two modes: focused mode and diffused mode. The focused mode is when we are focused intently on a problem or concept absorbing lots of information. Diffused mode is when our brain is relaxed and not focused on certain concepts or problems while it works them out in the background. This is important because most people just decide to learn and do problems in the focused mode only without ever taking into account the diffused mode of the brain which is equally important. You should switch modes of the brain after long, FOCUSED bouts of work or if you feel you’re getting stuck and frustrated with a problem. When you get stuck and frustrated with a problem it’s a sign you’re stuck in Einstellung. Einstellung is when you only look at a problem a certain way which could be the wrong way. Switching to diffused mode allows your brain to work on the problem in the background and finds new creative ways to attack the problem. Simple ways to switch to diffuse mode are:

  • Sleeping
  • Meditating
  • Listening to music
  • Exercising
  • Dancing
  • Brief amount of time playing of video games
  • Brief amounts of time surfing the web, texting friends, or checking emails

Try this next time you’re stuck on a problem or learning a new idea, conept, or topic.


When trying to memorize certain concepts or content you learned there are many ways to do so. Studies show that just rereading notes from the lecture is not affective in memorizing. Instead you want to focus on what you want to memorize, close your notes, and try to recall the information on your own without rereading. If there’s a couple things you can’t recall that’s okay. Just read your notes and try recalling it again. Using images and visuals is the best way for you to memorize content. Coming up with your own visuals or using the memory palace are good methods. The memory palace is visualizing items in a certain area of your home that’s relevant to what you want to remember. For example, if you need to remember items for your shopping list you can picture bread in the bread basket or eggs where you usually put them in the fridge. Coming with visuals like this will boost your memory and make you a more creative person. Something to remember when memorizing things is the difference between the working memory and the memory storage. Your working memory is when you’re storing items you are focused on learning. Your working memory can usually hold 4 items at a time. When you switch to diffuse mode the items are stored in your memory storage and in order to retain the information long term, your memory storage has to be visited a couple times every several days. Repetition is best over the course of several days rather than trying to repeat everything in one night or completely forget about it all together.


Chunking is important for your memory and to keep you from choking on a test. Chunking is when you take key concepts of the content and put them into context. There are steps to creating chunks:

  1. FOCUS on what you want to chunk
  2. UNDERSTAND what you want to chunk
  3. Put everything into context. Know when and where you need to use a concept

Chunking items and rehearsing those items can help you clear up space for your working memory and make it easier to just use the content without even thinking about it. Kinda like a baseball player when he learns to swing at a ball. There’s a lot of concepts and fundamentals to it but as he practices over and over the concepts become second nature and he doesn’t ever have to think about them. It’s the same thing with mathematics, science, or anything. Chunking is important for your performance.


Most people suffer from procrastination and it’s bad for your learning. Procrastination destroys the neurons in your brain making harder for you to learn deeply. This can be dangerous especially when learning new content. Most people procrastinate because the idea of temporary pleasure such as surfing the web, checking emails, or texting friends is better than the idea of doing math problems or other homework assignments. To overcome this you can use the pomodoro effect which is setting a 25 minute timer and you do focused hard work for 25 minutes and reward yourself with 5 minutes of surfing the web or doing whatever else. It’s also important to make a list of everything you need to do and then number them in order from the hardest task to the easiest task. You also want to put an end time of when you want to be done. This will help you stay focused and motivated because you can see the finish line. Using mental contrast is another way to motivate yourself to get your work done. Think of your future career and future vacations and the money(positive) and then think of your life now: student debt, ramen noodles, and a lot of work and learning(negative). Understand that everything you’re doing right now will be worth it. Other things that will help are understanding the cues that cause you to procrastinate and changing those cues. For example a cur for me is looking at my bed and cues me to sleep instead of do my work. When I wake up from my nap I’m less motivated and never get my work done. To overcome this I decided to never go in my room to do work. Changing your environment can help you out a lot in overcoming procrastination. Being able to end your procrastination habit will improve your learning, performance, and reduce stress.

Other information

To prep for tests you should find mentors such as your teachers to ask questions. Make sure that you use their time wisely because they are busy people. Ask questions about things you truly don’t understand. It’s also important to find a study group where you can bounce ideas off each other and criticize each other without feelings getting hurt. This will help be more productive and find more mistakes in your work where your brain originally thought it was right. Another key thing in studying for tests is to interleave which is doing different problems instead of doing the same type of problem over and over. This will help you understand the content better and not wast time on problems you’ve already mastered

Thanks for reading

I hope you enjoyed this review and learned something from it. I highly recommend you go pick up this book and read the whole thing there’s a lot of interesting and valuable tips to learn more effectively.