When we try to pick up a new subject, we usually read the material again and again. Even though memorisation and recall of information are less critical in the world today, it is still essential to have a modicum of information at our fingertips when we are disconnected from the online world.

Memorisation and recall remain a core requirement for current school assessments and examinations. Until that emphasis changes, developing study skills that can maximise learning and recall remain valuable. Repetition is indeed one of the main methods of learning — hence the saying “practice makes perfect” — but are there more effective ways to learn?

Some of us do not try to recall what we have read before reading the material again. But there is ample evidence from memory studies that attempting to recall improves our memory.

Let us look at some simple experiments in which participants learnt lists of words and then were tested on how much they could remember a week later. Among those who learnt by attempting to recall items during the learning sessions, the retention rate was more than 100 per cent better than those who simply studied the words.

Plain study sessions (just visual reviews) are much inferior to recall or retrieval practice when the desire is to improve performance on free-recall tests. It is far better for a student to write down all the key information — whether on paper or keyed into a computer — that he can recall from the material.

Another method of study commonly used is called concept mapping. The student has to map out all the main concepts he has read on paper or using a computer, tablet or smartphone. This requires elaborating and documenting conceptual understanding.

THE MOST EFFECTIVE WAY

Which way works best? In a study, Purdue University randomly assigned 80 undergraduate students to one of four groups — for single study, repeated study, retrieval practice and concept mapping.

The groups were assigned a science passage on sea otters to study. One week later, they were examined on both the facts and the conceptual elements of the passage. It took five minutes to read the passage.

The repeated study group read the passage four times. The single practice group did it once. The concept-mapping group spent 25 minutes mapping out the text’s main concepts. After spending 10 minutes doing an initial reading, the retrieval practice group listed any information they remembered from the text.

The study showed that students who used the retrieval practice technique scored significantly higher than students using the study-once, repeated-study and concept-mapping techniques. The mean percentage of correct answers was 67 per cent for retrieval practice, 27 per cent for single study, 49 per cent for repeated study and 45 per cent for concept-mapping.

What this means is that retrieval practice is the technique that should be taught whenever students need to know and recall the facts for examinations. Using flash cards is a simple method for teachers and students to employ: When a question is asked, the student has to recall the answer and check whether it is correct by flipping the card.

Today, mobile flash card software programs have made this process more convenient and accessible any time, anywhere, throughout the day.

SPACE OUT THE STUDYING

How often should one practise and at what intervals? The most effective way is well-spaced study, rather than studying at the last minute.

A review of more than 300 experiments found that 96 per cent of the studies showed a significant positive effect from spacing study over time, rather than studying all at once. What is also striking is that, within a meaningful timeframe, longer intervals between studying the same material can be beneficial. Longer intervals between study has stronger benefits for verbal information and motor-skills practice.

So how long should the study intervals be?

The best is to space the interval to just before the material is forgotten. Spacing study periods for the same material at increasingly longer intervals appears to be the optimal way of building long-term memory retention.

In practice, this means that, when the student is learning, focusing on new materials at higher frequency and older materials at lower frequency leads to the best long-term retention. This method is shown to be better than practising everything at one time just before an examination or spacing learning of material at a constant time period.

In other words, review first the information that you least know or remember, and that which you know or remember best at longer intervals. Repeated recall of material at progressively increasing intervals is better than cramming just before an examination.

However, the best way is to learn to value, use, apply and develop material that we learn. The focus for schools of the future should be on this — but even as they move towards tomorrow, teaching effective study skills should be a worthwhile exercise and understanding the science and incorporating the skills in today’s classroom are important.

ABOUT THE AUTHOR:

K Ranga Krishnan is Dean of the Duke-NUS Graduate Medical School Singapore. A clinician-scientist and psychiatrist, he chaired the Department of Psychiatry and Behavioural Sciences at Duke University Medical Centre from 1998 to 2009.

*This is part of a series on the way we learn. To read the other articles, visit http://tdy.sg/comkrishnan