Skip to main content

The Curve of Forgetting

The Curve of Forgetting

                                                 The Curve of Forgetting

The Curve of Forgetting describes how we retain or get rid of information that we take in.

It's based on a one-hour lecture.

On Day 1, at the beginning of the lecture, you go in knowing nothing, or 0%, (where the

curve starts at the baseline). At the end of the lecture you know 100% of what you know,

however well you know it (where the curve rises to its highest point).

By Day 2, if you have done nothing with the information you learned in that lecture,

didn't think about it again, read it again, etc. you will have lost 50%-80% of what you

learned. Our brains are constantly recording information on a temporary basis: scraps of

conversation heard on the sidewalk, what the person in front of you is wearing. Because

the information isn't necessary, and it doesn't come up again, our brains dump it all off,

along with what was learned in the lecture that you actually do want to hold on to!

By Day 7, we remember even less, and by Day 30, we retain about 2%-3% of the original

hour! This nicely coincides with midterm exams, and may account for feeling as if you've

never seen this before in your life when you're studying for exams - you may need to

actually re-learn it from scratch.

You can change the shape of the curve! A big signal to your brain to hold onto a specific

chunk of information is if that information comes up again. When the same thing is

repeated, your brain says, "Oh-there it is again, I better keep that." When you are exposed

to the same information repeatedly, it takes less and less time to "activate" the

information in your long term memory and it becomes easier for you to retrieve the

information when you need it.

Here's the formula, and the case for making time to review material: Within 24 hours of

getting the information - spend 10 minutes reviewing and you will raise the curve almost

to 100% again. A week later (Day 7), it only takes 5 minutes to "reactivate" the same

material, and again raise the curve. By Day 30, your brain will only need 2-4 minutes to

give you the feedback, "Yup, I know that. Got it."

Often students feel they can't possibly make time for a review session every day in their

schedules - they have trouble keeping up as it is. However, this review is an excellent

investment of time. If you don't review, you will need to spend 40-50 minutes re-learning

each hour of material later - do you have that kind of time? Cramming rarely plants the

information in your long term memory where you want it and can access it to do

assignments during the term as well as be ready for exams.

Depending on the course load, the general recommendation is to spend half an hour or so

every weekday, and 11⁄2 to 2 hours every weekend in review activity. Perhaps you only

have time to review 4 or 5 days of the week, and the curve stays at about the mid range.

That's OK, it's a lot better than the 2%-3% you would have retained if you hadn't

reviewed at all.

Many students are amazed at the difference reviewing regularly makes in how much they

understand and how well they understand and retain material. It's worth experimenting

for a couple weeks, just to see what difference it makes to you!



Counseling Services, Study Skills Program

University of Waterloo



                                                                             © 2005 AVID Center. All rights reserved