52 Aces

Learning, competition and capitalism

Memory

Photographic Memory

Want to know when new content shows up? Sign up for my newsletter here.

Transcript:

Let’s talk about photographic memory, a topic that I’ve been asked about more times than I can count.

First, we need to get one thing out of the way: photographic memory is a myth. That’s right, nobody has ever been able to prove that they have a photographic memory.

The reasons for this are related to what I talked about in Why Your Brain is Lazy, namely that your brain is forced into making trade-offs because it uses so much energy all the time.

When your brain encounters a stimulus in the world, it makes a decision to either keep it (what’s called “encoding”) or get rid of it. This is based on whether your brain sees the stimulus in question as salient.

If it is salient, then the encoding process will probably kick off, and if it’s just an everyday, run-of-the-mill stimulus, then it won’t.

Your brain will always make this trade-off, and no amount of training can circumvent such a fundamental biological principle. It’s an evolved survival strategy designed to reduce the amount of energy that gets wasted during the memory formation process, and there’s no way to escape it.

The question, then, is: why do so many people believe that photographic memory is real?

A simplified answer is that popular media loves to use it as a short-hand for high levels of intelligence and most people don’t question that stereotype.

Elon Musk is often used as an example of the hyper-genius who possesses a photographic memory, but as far as I know that claim about his memory has never been tested.

The more complete answer is that there are people who do exhibit extraordinary memory abilities, and those abilities get mis-classified as photographic memory.

There are some people who could be called savants who have exhibited world-class memory abilities. Kim Peek, the inspiration for Dustin Hoffman’s character in Rainman, could absorb incredible amounts of information in one sitting. Stephen Wiltshire is a savant who can recreate skylines in incredible detail after seeing them once.

These savants do have great memories, but there are two important qualifiers to consider: 1) their memories are never good enough to qualify as “photographic” (Stephen Wiltshire’s pictures contain many mistakes, for example), and 2) the memory abilities they possess appear to come at a huge cost, as they’re not able to take care of basic everyday tasks.

So their increased capacity for memory is a trade-off that doesn’t appear to be beneficial to their survival, which says a lot about how evolved the standard memory algorithm is.

Some people also exhibit what’s called hyperthymesia, or superior autobiographical memory. This group of people have an uncanny ability to remember the minute details of their day-to-day lives.

These individuals appear to have some kind of focused memory algorithm that doesn’t envelop their overall memory abilities. In other words, their brain prioritizes a specific type of information for encoding, but that benefit doesn’t overlap with any other facet of their memory. 

One last example is the group of people who compete at memory competitions. Memory competitors do things like memorize entire decks of cards within a few minutes.

This is all accomplished with the use of what are called mnemonics, which are memory tricks that can be used to memorize (for short periods of time and with lots of practice) specific bits of information.

Nobody with a claimed photographic memory has ever won a world memory championship, which is hilarious since you’d think that’s where they’d show up. If you had a photographic memory, why not cash in on it?

Anyway, the general idea to take out of all this is that photographic memory doesn’t exist. You can improve your memory in specific ways with specific techniques, but overall you can’t get away from the fact that your memory automatically tosses most of what it encounters.

Why Your Brain is Lazy

Want to know when new content shows up? Sign up for my newsletter here.

Transcript:

Let’s talk about why your brain is lazy.

The short explanation is it’s lazy because it has to conserve energy as much as possible.

Energy in turn needs to be conserved because, even though your brain only represents about 2% of your total body mass, it burns through about 20% of your daily calories.

In other words, your brain’s an energy hog.

The reason it’s a hog is because it runs everything in your body, and keeping the human body running is, to put it lightly, a complex task.

Why is it so complex? Well, most of what you do is unconscious. Conscious thought only represents a small portion of the work your brain is doing.

For example, you don’t run your nervous system or maintain your internal organs with conscious thought. That’s all happening in the background, and all of it takes energy.

Your brain is never really turned “off” as a result, even when you think it is — it’s always busy managing something in your body.

This is why the whole “you only use 10% of your brain” myth is such a joke. Your brain is a constant hive of neuronal activity at all times, and it’s because the brain is busy running the whole system. This is true even when you’re asleep — so even if you think you’re idle and nothing is happening, your brain is busy running everything.

Anyway, because it’s so busy allocating resources all over your body, your brain has developed a long list of cognitive shortcuts as a means of saving energy.

Forgetting is the best example of a cognitive shortcut: your brain forgets most of what it encounters because it would be too energy-intensive to remember tons of useless data.

The brain is thus optimized to be, to borrow someone else’s terminology, a “change detector.”

Your brain’s lazy memory algorithm focuses on encoding new memories that are salient, and dropping everything that isn’t memorable.

For example, you’ll remember if, during your daily drive to work, a zebra steps in front of your car even though you live in a major metropolitan area. That’s such an unusual event that it’s guaranteed you’ll remember it — it’s so salient that your brain will encode it as a memory.

This is why repetition is important in learning: you need to tell your brain (through repeated exposures) that a given stimulus is worth the energy expenditures involved in remembering it.

Your brain does this in order to take note of environmental cues that could potentially influence your survival. 

We suck up anything that’s unusual because big changes in our environment can be dangerous. A zebra running around in the street could be indicative of a problem at the local zoo, which in turn could mean there are dangerous animals running around that could eat you.

With all of these lazy shortcuts, your brain is making a trade-off of some kind. The brain is asking itself: “Is it worth pouring resources into this?” And if the answer is “no” then the brain doesn’t prioritize itself around that stimulus.

People get frustrated with these shortcuts, but they’re an indicator of a healthy brain. There are exceptions, like Alzheimer’s or CTE, but in general shortcuts like forgetting mean your brain is acting in accordance with its lazy nature.

The key idea to pull from all of this is that your brain does what it does for a good reason, and you won’t be able to learn or use your memory well if you don’t understand these internal dynamics. 

Much of learning revolves around finding ways to use your brain’s built-in mechanisms for your benefit, but there will always be limitations. Don’t get frustrated, just accept that your brain will never be perfect.

To put this all in perspective: supercomputers that take up entire floors of industrial buildings can’t touch the capabilities of the human brain. 

How is it that such vast amounts of electrical and computing power come up short when trying to handle tasks, like language, that we find trivial? This is one of the enduring mysteries of the brain. But it should clue you in to the fact that your brain, despite its laziness, is not as flawed as you might think.