How We Learn: The Surprising Truth About When, Where, and Why It Happens

by Benedict Carey

Cramming works fine as a last resort, a way to ramp up fast for an exam if you’re behind and have no choice. It’s a time-tested solution, after all. The downside is that, after the test, you won’t remember a whole lot of what you “learned”—if you remember any at all. The reason is that the brain can sharpen a memory only after some forgetting has occurred. In this way, memory is like a muscle: A little “breakdown” allows it to subsequently build greater strength. Cramming, by definition, prevents this from happening. Spaced rehearsal or study (see previous question) or self-examination (see next question) are far more effective ways to prepare. You’ll remember the material longer and be able to carry it into the next course or semester easily. Studies find that people remember up to twice as much of material that they rehearsed in spaced or tested sessions than during cramming. If you must cram, do so in courses that are not central to your main area of focus.