“You try to get good marks by studying just to deal with the tests ahead.” That’s a bad idea. The brain is not that easily fooled.

Let’s play Quora again! Here’s a question in the category Neuroscience: How can one improve their ability to learn?

There are a couple good answers there, most notably living healthy and be physically active. A little caffeine would probably not hurt either, for most people. But this is not really a question that should be confined to neuroscience. Learning is a process influenced by many factors. Let us look at a couple of them.

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To stick with neuroscience at first, how do we learn? We learn in three phases, four if you count the fleeting phase of sensory input. Next is the bottleneck of short-term memory. On average, an adult human has the ability to keep 7 items in short-term memory, but this ranges from 5 to 9 without a huge impact on daily life. You may be able to increase this number by 1 with systematic training, and it may give you an edge in a few situations. Like remembering Norwegian phone numbers, which are 8 digits. ^_^ (Seriously, for some years most of the calls I received were people dialing wrong number. The surge of smartphones has nearly put an end to that though.)

In practice, short-term memory does not have the huge impact one would expect. Most things we notice are either deemed unimportant and quickly forgotten, or passed straight on to working memory. While we hold things in short-term memory just for a few seconds, working memory may keep things floating around for several minutes at least. Memory loss after concussions and electroshock imply that memories may not be transferred to long-term memory until after half an hour or two, but some of this processing is surely subconscious.

If we had short-term memory but not working memory, we would not be able to make sense of things like novels, scientific texts or poems, where we have to remember much more than a handful of words, but don’t commit every detail (or even most of the details) to lasting memory. We automatically select the parts we think are important, and keep these around and put them together into meaningful structures, such as mental images or stories. It is unclear to what degree our furry friends have the same ability, since they can’t talk, but our use of working memory seems pretty special.

If the working memory runs full, which it easily does during focused study, you can not add more without losing some of what you already have. There is another bottleneck in the transfer of knowledge from working memory to long-term memory, which is encoded as actual physical changes in the neurons (nerve cells). At a minimum, the sensitivity of certain synapses (contact points between neurons) is changed. Over time the physical size of synapses may change, new synapses may grow, and the tendrils of the neurons may change in shape or size a little. In a few parts of the adult brain, new neurons are born. This applies mostly to the hippocampus, a small part that seems to serve as the brains “index” where links to memories are laid down. A lot of memories exist in the adult brain that cannot be recalled. Electric stimulation can cause such memories to appear, but there seems to be no system in them, except a rough categorization into smell, sight, sound etc. Without the hippocampus, memory as we know it cannot exist, although primitive conditioned reactions can bypass it.

Transfer from working memory to long-term memory is greatly aided by sleep, notably deep (delta) sleep which helps brain cells grow, and dream (REM) sleep which helps integrate memories. Also, during sleep we don’t cram more data into the working memory, so it gets a chance to unload.

Recent studies show that moderate physical activity also helps the brain encode information from working memory to long-term memory. This could be because our species did not originate in chairs, but our ancestors spent much of their non-sleep time on their feet. Or it might be as simple as the increased blood flow caused by a more vigorous heartbeat.

This explains why strategic use of sleep and exercise can improve learning, all other things being equal. It also explains why cramming for long hours is wasted time, and it is better to study in intervals.

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But neuroscience is not the only aspect of learning, and not the one that makes the most difference in practice, except for the few where it does not work as it should. There is much that can be done to improve learning through the “software”, the data structures, rather than the “hardware” of the brain. I want to say a bit about this.

Adults learn mainly by association. Babies have nothing but basic instincts to associate with, but have a higher ability to just pack random data into their brains and retain them. Then again they spend more than half their time in REM or delta brainwave states, with delta even appearing while awake for a while. As the infants become children, this ability begins to fade, and in teenagers it goes downhill fast. For the rest of our lives, we depend heavily on association.

If you were introduced to many different experiences as a child, you will have the hooks to associate similar things. For instance, if you spent a year of your childhood in a foreign country, you probably have a rudimentary knowledge of the language. This makes it a lot easier to pick up that language later and learn to speak it fluently.

What if we simply don’t have the relevant experiences? Well, we can still learn through repetition. I have occasionally mentioned Spaced Repetition, a system where you recall a fact repeatedly but with exponentially increasing intervals, so as to recall it as close to possible before it is forgotten. It is possible to learn utterly alien things this way, but it takes some time. You cannot do this just before an exam, to put it that way, or just before you go on a vacation to a foreign country and need to understand a bit of the language.

Another strategy is “bridge building”, where you learn something unnecessary but related to what you already know, and then use this knowledge again to learn what you really need. Arguably much of school is spent doing this, learning useless stuff so that we can bridge the gap from counting on our fingers to making a Mars rover. Of course, different things are useful for different people. But learning by association is so powerful that it can be used as a conscious strategy to learn otherwise meaningless information.

The impressive memory feats of memory artists are usually done this way: By associating new data with existing structures in a form that is not necessarily entirely sane if you were to describe it to an outsider. For instance, English is my third language and I may want to remember the word “gaffe”, a social blunder or embarrassing mistake. Being already familiar with the giraffe, which has a similar name in my native language, I may imagine a giraffe tripping over its own legs. There is no actual connection between gaffe and giraffe (I looked it up), but it causes my brain to build a “bridge” from a word I already know to one I don’t. Your giraffes may vary.

The more associations we build to a new fact, and the more vivid they are, the better we learn. Part of the “more” is location. You may have seen people who walk into a room, can’t remember why they came, and have to go back to the room they came from. Then they remember. So that shows that even a small change in location can influence memory. We can turn the tables on this by learning something, then going to another room and recall it. This can be enough for the brain to not archive it as location-specific, but general knowledge. (Of course, if we only need to remember it in one specific place, it is best to learn it there if possible. Or at least somewhere similar.)

Neuroscientifically, it may not be strictly necessary to go through all these tricks to learn things. There are a few scattered persons who seem able to remember pretty much everything in reasonable detail – whether they want to or not. This is a mixed blessing at best, as an endless torrent of memories runs through their head all the time. Remembering just the things that fit into our world and that we meet repeatedly makes life rather easier. So that’s why, if we expect to need something we learn, we should focus on just these two things: Integrate it in our world by linking it to things we know, and repeat recalling it, preferably in different places. Good luck!