Why this study?
Despite its importance for success in exams, many students simply don’t know how to revise. This often culminates in them cramming as much as they can in the days (and even hours) before the exam. But is this cramming style effective? What if spacing out your revision sessions was more effective? This would mean students could do the same amount of work but yield much greater results from it.
Researcher Nicholas Cepeda and colleagues from The University of California, the Massachusetts Institute of Technology, and the University of South Florida devised an experiment to explore the optimum amount of time to leave between revision sessions. Their study, published in 2009 in Psychological Science, offers valuable insight into this.
They had 1,354 participants learn 32 obscure but true trivia facts. These included questions such as ‘who invented snow golf?’ and ‘which European nation consumes the most spicy Mexican food?’. They then divided the participants into 26 groups, each with a different gap before their next revision session and a different amount of time after that before their final test. They then compared how many successful answers the participants recorded in their final exam to see what the optimum amount of time to leave between study sessions was.
The main findings
They found that after learning the material, the optimum gap to leave before revisiting the same material depends on how far after that second revision session the test is. The researchers found the following timings offer a good guideline:
|How Far Away The Test Is
|Gap Between Revision Sessions
The ‘Spacing Effect’ is one of the longest and most enduring findings in cognitive psychology. It was first detailed in 1885 by German psychologist Hermann Ebbinghaus who found that humans tend to forget large amounts of information if they only learn something once. Since then, research has consistently shown the power of spacing out your learning. This is an effective technique, as it allows time for the material to be forgotten and re-learnt. This process allows someone to cement it into their long-term memory.
In some studies, using spacing instead of cramming has resulted in a 10% to 30% difference in final test results. This finding has been found in a range of tasks, including remembering key words, random facts, or solving maths problems.
The gap between study sessions listed in the study above is not set in stone and other research may recommend slightly different gaps. The researchers of this study state that “to put it simply, if you want to know the optimal distribution of your study time, you need to decide how long you wish to remember something”. The recommended gaps are intended more as guidelines. As a rough rule of thumb, the closer you are to forgetting a piece of information (before it completely drops out of your brain), the more likely it is that you will benefit from revisiting it.
Spacing in the classroom
With students no longer doing modular exams, the ability to retain and recall large pieces of information has become even more important. It is now a premium skill. Teachers can help students improve their long-term memory by spacing out the material and revisiting it regularly.
Just as actors don’t leave all their rehearsals until the day before the opening night of a play, and athletes don’t only train the day before the match, so students should regularly return to previously learnt material.
As the authors of the study note, this is “at odds with many conventional educational practices—for example, study of a single topic being confined within a given week of a course”. To commit something to memory, it takes time and repetition.
Likewise, students need to be made aware of the importance of spacing. Essentially, when they are revising, it is far more effective to do 1 hour a day for 7 days than it is to do 7 hours in one day. The nearer it gets to an exam, the more often they will need to return to the material. This is something for students to carefully consider when doing revision timetables, as it is not just the ‘what’ that matters, but the ‘when’ as well.