Studying for Exams? Here’s a Suggestion to Improve Memory Retention
In a recent study by van Dongen et al. (2016) it is suggested that some vigorous exercise could be a way to improve memory retention after study. This fits in very nicely with the fact that study or memorizing of material is best done in the morning when the pre-frontal cortex of the brain is activated and more able to attend and integrate material.
We know, from previous animal studies, that noradrenaline and dopamine are brain chemicals which are released during exercise, and in those animal studies there were significant improvements in memory (for instance, mice in a maze were most likely to find the way out if they had previously exercised.). Van Dongen and associates decided to replicate these studies in humans to see if there would be similar memory improvement effects.
In the study 72 participants were given 90 pictures which they had to try and memorize in 40 minutes. They were split into three groups: Group 1 exercised vigorously for 35 minutes immediately after the memorization task; Group 2 sat in a quiet room for four hours immediately after the memorization task, and then did the same 35 minutes of vigorous exercise; Group 3 did no exercise at all.
After two days the participants were asked to recall the pictures. These results indicated that if one exercised immediately after committing something to memory, or did no exercise at all, there was no difference. However, there was a significantly higher score for the second group who exercised four hours after the task compared to the first and third group. These results demonstrated that doing aerobic exercise four hours after memorizing something improved how well that material was retained.
This begs the question, why does delayed exercise improve long-term memory, compared to immediate exercise, which does not? Neuroplasticity, as we know, makes new communication links between brain cells, and is modulated by brain chemicals such as dopamine and noradrenaline. The researchers suggest a) that possibly the high dopamine and noradrenaline levels, which may occur immediately after learning, drop after a few hours, or b) intense exercise helps to prolong the memory consolidation process. However, knowing just when to do that exercise is something that the researchers plan to investigate further, as it may be that four hours between committing something to memory and exercise may not be the only time that is optimal. It could be that one could commit material to memory optimally after one or two hours.
This could be a take-home message for many of you – actors who need to memorize lines, dancers who need to remember choreography, musicians who need to remember scores, doctors sitting their primary and fellowship exams, university students and HSC students preparing for exams. I am sure the list could go on.
As yet, it is not known what could be the optimal time to exercise after endeavouring to memorize material. But there is a window of opportunity here, to do an experiment on yourself. It could be that doing vigorous exercise half an hour, one hour, or two hours after study, could help you better remember material. It’s certainly worth a try. For best results, do your study up to 12 noon on your days off (when the pre-frontal cortex is working well), then, at a time of your choosing, up to four hours later, do some aerobic exercise (a run or fast walk). After two or three days, test yourself and see how much you remember from your study. If you’re really serious about this, try this over several different times, record your results, and see what works for you.\
The reference to the van Dongen study is below. It might be worthwhile reading.
Dr. Patsy Tremayne
- V. van Dongen, I.H.P. Kersten, I.C. Wagner, R.G.M. Morris, G. Fernandez. (2016). Physical exercise performed four hours after learning improves memory retention and increases hippocampal pattern similarity during retrieval. Current Biology, 26, 13, 1722-27.