The Neurobiology of Learning
With residencies becoming increasingly competitive, medical students today find themselves often juggling far more than simply staying on top of their course load. Students are getting involved in more research, mentorship, volunteering and outreach, leaving them with little time to study and master material outside of class. Furthermore, schools are placing a greater emphasis on small-group learning, podcasts and flipped classroom paradigms that put an even greater onus on students to learn quickly and efficiently. At the same time, with the ubiquity of mobile technology, students now have the ability to access and engage their learning material in more ways than ever before; from physical books and digital PDFs, to flashcards, to videos and interactive games, it is important for students to realize what methods and learning systems will best maximize their time and give them the best chance to succeed. In order to optimize how you learn, you must work with biology, not against it.
Developmental psychologists have explored the mechanisms that underlie how children are able to amass an exorbitant amount of information in a relatively quick time period. Two recurrent themes help elucidate this phenomenon: repetition and bottom-up learning. I will explore these themes and how they can be utilized to maximize your learning efficiency, but first, lets have a quick look at the neurobiology of learning by working through a simple example. I was born in El Paso, Texas. You have (probably) never seen this statement before — in other words, it’s a novel piece of information that you must now integrate into the 100 million gigabytes of knowledge your brain can store.
First, your eyes viewed the text on the screen, allowing your retina to transduce the physical electromagnetic stimulus (light), through a series of biochemical steps, into the electrochemical neural impulse (signal) that your brain can interpret. Next, your brain automatically associated the various ideas, or mental representations, contained within the statement (such as the geographic location of Texas, the idea of birth and reproduction, the images of children and hospitals, etc.) in order to comprehend the statement. This led to the creation of new connections between neurons in your brain. These connections are strengthened by a process known as long term potentiation, or LTP. LTP is a biochemical mechanism that essentially explains how neurons within your brain sustain new synaptic connections. In short, when neurons fire simultaneously, they are able to connect to one another, and the more they fire, the stronger the connection is. This is the neural basis of learning — connecting several pieces of previously unrelated information together to form a new neural network.
Applying Your Knowledge of the Neurobiology Behind Learning
So how does this relate to learning? Well, since neural connections are strengthened the more they fire, biology is telling us that in order to make a strong connection (essentially learn something really well), you must repeatedly revisit and expose yourself to the information you are trying to learn. In addition, a solid understanding of the basics must be established, before details and more complicated material can be mastered. For example, in order to learn calculus, you must first learn how to add and subtract extremely well, and then you can add the complexities of calculus. This same principle applies to most subjects. In trying to take advantage of the neurobiological principles underlying learning to help you be a more efficient learner, I have created a simple and pragmatic schedule:
If you follow a study plan similar to the one laid above, by the time you are tested on the material, you have gone over everything seven or more times — now that’s repetition! In addition, you are employing bottom-up learning, which is learning the basics, and then adding layers of detail and complexity as you solidify the concepts crucial for understanding the material. Here is another diagram that might help you create your own maximally effective study plan:
So does this mean you have to sit in a room and repeat concepts from class for hours on end to maximize your study efficiency? Of course not! In fact, research suggests that taking effective breaks, “changing up” your tactics as you study, and even taking naps can do wonders for memory retention and your study performance! Let’s take a look at sleep in more detail.
The Importance of Sleep
One extremely important thing to keep in mind is that LTP is most efficient when you sleep. You need to sleep in order to consolidate what you have learned — power naps and a full night’s rest are essential in order to provide your brain with an adequate amount of time to cement what you are learning, and be able to recall and retrieve it on test day and beyond. According to a study at UC Berkeley, an hour’s nap was able to dramatically boost and restore students’ brainpower! The longer we stay awake, our minds become more and more sluggish, making it more difficult to engage new tasks and learn new information. In the study, subjects who took a 90-minute nap in the middle of the day were compared to a second group who did not take a nap. Both groups were presented learning tasks at the end of the day, and the group that took a nap had superior performance and an increased capacity to learn compared to the group who did not. Researchers traced this back to a hypothesis that the brain needs sleep to clear our short-term memories and make room for new information. In fact, think back to when you were in preschool or kindergarten. Back then, we always had mid-day naps and a biphasic sleep cycle. Research with preschoolers has shown that, even at such a young age, naps are able to enhance learning in preschool children. In fact, the kids who had the biggest improvement in learning associated with naps were those kids who were habitual “nappers.” So if you’re trying to study for that big exam, the solution is NOT to lock yourself in a room and repeat the material to yourself over and over for hours on end. Take breaks! And take a nap! A 60 to 90 minute nap in the middle of your study session will allow you to refresh your mind, and your brain will be able to clear its short-term memory, making you an even more effective learner after you wake up.
Useful vs. Not-So-Useful Study Strategies
Similarly, when you are studying, it is important to use different learning tools and study techniques to help solidify the information in your head. Studying can take a variety of different forms. Everything from reading and highlighting, utilizing diagrams and summary images, to summarizing, self-teaching and practice questions. A study in 2013 in the Journal of Psychological Science took a look at common study methods, and determined the most effective study techniques for students. The study found that active practice was the most effective; this can include practice problems, and mini-study sessions with actively applied practice. The least effective techniques included most passive methods like reading and highlighting, summarizing, mnemonics and diagrams. What does this mean for you? When considering different study methods and tools to employ when you sit down at your desk, remember that active practice and simulating testing and evaluative conditions will yield the most effective learning. You are training and engaging your brain in such a way that it is used to interacting and thinking about the material you are trying to learn. Repetition is great for your brain and neurons, but you have to make sure that you’re repeating the right stuff! Prioritize repeating the critical thinking aspects of the material you’re trying to learn over dry, static facts will go a long way in promoting more effective learning and retention. Seek out practice questions, create and answer flashcards, even teaching a fellow classmate and having them ask you questions. By using both effective learning modalities and repetition, you will be working with biology, and not against it.
Contributing Writer
University of California, Irvine School of Medicine
Wei (call him Derek) is currently a Class of 2017 medical student at UC Irvine School of Medicine. He graduated from UC Berkeley in 2009 with a major in biochemistry and psychology. He took a few years off school teaching MCAT prep and working in clinical imaging research in Alzheimer disease and osteoporosis. He is interested in the topics of medical education and technology, and he is interested in specializing in anesthesiology or interventional radiology.
Contributing Writer
University of California, Irvine School of Medicine
Ron is a medical student at the UC Irvine School of Medicine. He is interested in regenerative medicine, and in particular, the treatment of neurodegenerative diseases with stem cells. He graduated from UC Berkeley with a double major in neurobiology and psychology, and has been interested in exploring how the brain can regenerate itself, and how new therapeutic techniques, such as intraventricular stem cell transplantations can enhance the brain's ability to heal itself.