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I always forget everything within 10 minutes of lecture, but somehow it paid off on my midterm…


It’s a frustrating feeling.

You know you had it, but now it’s gone.

At one point you remember busting out entire problem sets in Physics 2 with no problem: Ohm’s Law, Kirchoff’s Current and Voltage Laws, equivalent resistances….

But for the life of you, here comes the first Electronics quiz, and all you can do is sit there and stare at that monstrous circuit staring you in the face.


In an ideal world, we’d all like to learn the basics, get them down really well, and then maintain them at the forefront of our memories – like an instant-access library immediately within our grasp.

And for a lot of engineering students, it’s one of their biggest frustrations:

You learn how to solve for relative velocities in Physics 1, but then have completely forgotten by the time Dynamics rolls around.

It seems like a waste of time – always having to go back and re-learn what you once knew, just so that you can stack something more complex on top of it.

You feel like you should remember this stuff.

And your professors tend to look at you with a raised eyebrow if you don’t.

(Photo: giphy.com)


Now for the hilarious part…

The fact that you forgot all that stuff?

It will make that memory STRONGER than it ever would have been, had you never forgot it in the first place.

Let’s take a look at a hypothetical.


The Frontrunner vs. The Underdog


We’ve got two students, Johnny and Sally, who are both enrolled in Thermo this semester (god bless ’em).

Johnny is obsessed with remembering everything from his classes. He takes annoyingly neat and detailed notes, studies intensely for exams. He even continues to periodically review his study sheets after the course is over. If you ask him about conservation of energy, or the Ideal Gas Law, the information is at the tip of his tongue.

So come the start of Thermo class, he feels prepared.

Much more so than Sally….

Sally loves engineering, but tends to be a little more lax in her study habits. In the end, she learns everything she needs to for the exams, but tends to push things to the absolute last-minute, despite her best intentions. Within 24-hours of her mad-dash to learn enough basic thermo for her physics final, she also can whip out a pretty good explanation of those same concepts Johnny knows so well. But 2 weeks afterwards, it’s mostly gone, and she’d have a hard time telling you what a “Joule” is without Wikipedia on hand.

Needless to say, when classes start up again, and the Thermo professor starts busting out PV=nRT, and talking about constant volume vs. constant pressure systems, Sally is lost, while Johnny is feeling pretty comfortable.

The kicker?

Sally will outperform Johnny on the first exam.


The Power of Forgetting


Memory researchers have come across an interesting phenomenon.

It was once well established that memory followed a simple relationship. You learn something. The more you repeat and reinforce that information, the longer it stays in your memory.

“If you don’t use it, you lose it,” they say.

This is what we all “know” today, and it all stems from what’s known as Ebbinghaus’s Forgetting Curve, established waaayy back in 1880.

(Photo: How We Learn)


However the picture is actually much less clear. Turns out, a dude named Phillip Ballard, an English researcher from the early 1900s, found that after attempting to learn a few verses of poetry, students spontaneously remembered MORE material 2 days later that they had immediately after learning it the first time.

How is this possible?

Well it turns out, the “if you don’t use it, you lose it” platitude isn’t actually true.

Once you learn something, it is permanently stored in your memory… FOREVER.

So every stupid little fact you’ve intentionally attempted to memorize is actually in there somewhere.

But what you do lose with time is your ability to RETRIEVE that information.

Old, unused memories essentially “get lost” somewhere deep in the folds of your neocortex, like an ancient useless book in the basement of a disorganized library.

Interestingly enough though, the more effort you have to put in to try to retrieve a piece of information stored in your dome, the stronger your ability to retrieve that memory becomes. Researchers call this “retrieval strength,” and it explains why Ballard’s students were able to improve their memory performance through subsequent testing without any additional exposure to the material.

Your brain is basically saying:

“Oh shit, this thing didn’t seem important at the time, but turns out I actually need it. Let’s keep this up front-and-center because looks like I’ll probably need it again.”

The “librarian” doesn’t want to have to make the long journey into the basement and sift through hundreds of old books again, if you’re gonna need that book again in a week. Better to just put it up by the front desk for when you inevitably come back and ask for it again.

So back to Thermo…


Sally’s Revenge


Sally is utterly confused after the first class, and heads back to her dorm to see if she can work through the first problem set.

Struggling to remember what PV=nRT means, and what she might have used it for, she spends an hour slowly working through the new material. Though painful, she feels better and even starts to remember some of the problems from her physics final.

Johnny on the other hand, is livin’ on easy street.

(Photo: knowyourmeme.com)


After class he takes a stroll down to the lounge, whips out his book and cooly and calmly knocks out 9 problems in ~20 minutes. He refreshes his memory on the notes from the day’s class, and is very happy with himself.

Flash forward 3 weeks.

The quiz sheets are passed out. Lo and behold, an ideal gas mixture problem shows up.


Johnny is calm and feels confident. He’s seen the material over and over again for the last 3 weeks and so starts working through it quickly, and blasts through the quiz in about 5 minutes, not realizing he left his temperature in Celcius.

Sally is stressing a little bit, but thinks she knows how to do it. She starts to break down the problem, but then remembers that she screwed up one of her practice problems because she forgot to convert to Kelvin before plugging in. It takes her the whole 20 minutes allotted to finish the quiz, but she gets through it.

A week later, Sally is elated with her 25/25, while Johnny is surprised to see a 15/25 on his sheet.

The moral of the story?

If you really want to learn something, sometimes forgetting is the best thing you can do.


How to forget properly


So what should you do?

1. Don’t continue to review your notes!

You need to give your brain a period of time to digest and re-organize new information after you’ve learned it for the first time.

(Photo: memecenter.com)


This will also give you the opportunity to “forget” a little, so that what you do next has much more impact…

2. Test yourself later that night.

Without looking at any notes or cracking your textbook, test yourself on material covered in lecture that day. Start with a couple different problems from the lecture or from your homework and try to solve them from scratch.

This will significantly increase your “retrieval strength” of the memories you need to solve the problems you need to – but only if you’ve started to forget those things a little first.

It should be DIFFICULT to pull these things back out of your memory. That’s what will solidify them in your brain.

3. Test yourself again over the weekend.

Continue to avoid review at all costs. Do what you need to finish your problem sets for the week, but beyond that, stay away from your notes until you have the chance to test yourself on the material from the week one more time.

Test yourself in the same way as you did the night after your first class. This will further increase the retrieval strength of those critical steps, concepts, and equations you’ll need for your exams, while keeping the rest of your brain clear of unnecessary information.

Then, and only then, allow yourself to go back through your notes and example problems to work on areas you missed during your testing.

Apply this methodology and you’ll start to MASSIVELY outpace your classmates as the semester rolls on.


All you have to do is be willing to forget a ‘lil bit.

(Feature Photo Credit: simpleinsomnia)


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