Why cramming for exams never works: Brains ‘panic’ after last-minute revision and can’t take in new information



    • ‘Retrieval practice’, can protect the memory against the effects of stress
    • Study of students showed they remembered more in stressful situations
    • Students using this method have an advantage over those who simply re-read material in order to memorize it, claims the research

    November 25, 2016: Every student who has panicked while reading the same page of a textbook over and over again may suspect this.

    But stress cramming for an exam does not work, because the facts are likely to be lost from your memory.

    Instead it is best to learn through practice tests to protect your brain from the effects of stress, with a study showing that we remember more this way.

    In findings which will also help adults training at work, re-reading was found to work far less well under stress than active learning through practice.

    Under pressure, researchers examining 120 students found those learning off a page remembered only an average of seven out of 30 words and images. But those who learned the words and images, then sat a timed practice test, were able to retrieve 11 of the 30 on average from their memory.

    Senior study author Dr Ayanna Thomas, an associate psychology professor from Tufts University in Masachusetts, said: ‘Typically, people under stress are less effective at retrieving information from memory.

    ‘We now show for the first time that the right learning strategy, in this case retrieval practice or taking practice tests, results in such strong memory representations that even under high levels of stress, subjects are still able to access their memories.’

    Co-author Amy Smith, a graduate psychology student at Tufts, added: ‘Our results suggest that it is not necessarily a matter of how much or how long someone studies, but how they study.’

    ‘Retrieval’ practice, or using practice tests, had already been found to work better when revising. But the new study, published in the journal Science, looked at how the two strategies worked under added pressure from stress.

    The research team asked participants to learn a set of 30 words and 30 images which flashed up for a few seconds each on a computer screen. They took notes, typing sentences using the items they had seen, with some then taking practice tests and the rest studying conventionally.


    The stress came after a 24-hour break when half of each group were forced to give an unexpected, impromptu speech and solve math problems in front of two judges, three peers and a video camera.

    Their memory was tested during the stressful situation and then 20 minutes afterwards, to examine the brain under immediate and delayed stress responses.

    Those who learned using the practice tests showed little damage to their memory from the stress, remembering an average of 11 out of 30 items compared to 10 for their non-stressed counterparts.

    But those who learned by re-reading saw the items they remembered fall from just under nine items to seven on average.

    It has previously been suggested that learning through practice tests allows the brain to encode knowledge, making it more likely to be stored.


    Dr Thomas said: ‘Our one study is certainly not the final say on how retrieval practice influences memory under stress, but I can see this being applicable to any individual who has to retrieve complex information under high stakes.

    ‘Especially for educators, where big exams can put a great deal of pressure on students, I really encourage employing more frequent more low-stakes testing in context of their instruction.’