How to enhance your memory capacity

We are living in a midst of a revision hell at the moment, spending our days desperately trying to learn lecture content and do the required reading that we never did back in terms 1 and 2 – the good old days. Revision is primarily a task of memorising, whether it is of facts, quotations, case studies or equations. Whilst most of us struggle to remember complex facts and worry about having ‘mind blanks’ in exams, others possess exceptional memory abilities. Take World Memory Championship winner Wang Feng, who memorised 2,280 numerals within an hour and a shuffled pack of 52 cards in 24.22 seconds. Or Russian journalist Solomon Shereshevsky who could memorise and recall poems in foreign languages in just minutes. How is it possible to have such astonishing memories? Are these people evolutionary super-humans with different brains to everyone else? Or have they just learnt memory enhancing skills that anyone could acquire with enough practice?

Could it be that people with superior memories have structural differences in their brains that allow them to remember things more easily?

Through studying brain-damaged patients who have lost parts of their memory, scientists have found that certain areas of the brain are involved in storing memory. For example, the hippocampus seems to be involved in spatial and declarative learning (acquiring factual knowledge) whilst the amygdala is involved in emotional memories. Encoding and storing memories is believed to occur in a process called long-term potentiation, in which greater amounts of neurotransmitter is released at synapses between neurons, strengthening the connections. Could it be that people with superior memories have structural differences in their brains (i.e. bigger hippocampi and amygdala) that allow them to remember things more easily?

Actually, scientists at University College London have found, the answer is no. Ten candidates from the World Memory Championships (an annual event held in London, if you’re interested in competing) with superior memories and ten normal subjects were tested in a series of memory tasks whilst having their brains scanned. As expected, the superior memorisers showed improved performance in working and long-term memory tests, as these tasks were similar to those commonly featured in memory competitions. However, no differences in gray matter volume were found between the participants. Also, although superior memorisers showed increased activity in areas such as the medial parietal cortex, retrosplenial cortex and right posterior hippocampus during information processing tasks, this activation was not as a function of better performance.

On debriefing, the scientists found out that the superior memorisers had made great use of mnemonics, which are strategies for encoding information with the sole purpose of making it more memorable

So what was responsible for the superior memory participants’ enhanced remembering abilities? On debriefing, the scientists found out that the superior memorisers had made great use of mnemonics, which are strategies for encoding information with the sole purpose of making it more memorable. In particular, they had used the ‘method of loci’ technique, an ancient Greek mnemonic commonly called the ‘mental walk’. The technique involves thinking of a familiar route and visualising to-be-remembered items at points along the way; before retracing the routes at recall. The scientists concluded that the different brain areas activated in the superior memory participants reflected the use of this mnemonic strategy.

So how can we learn from these memorising extraordinaires to improve our own performance in exams and life in general? It may be old advice, but it seems that mnemonics really do help, particularly for complex facts that don’t seem to make logical sense. As well as the method of loci, acronyms can also help. How many of us learnt the seven functions of living things back in year 6 by learning ‘MRS NERG’ for example? Rhymes often facilitate learning, too: in Psychology we are taught over and over again that ‘Cells that fire together, wire together’ which explains a principle known as Hebbian learning . Alternatively, visualising an image that corresponds with a concept is often useful, if on retrieval, the image will trigger the factual memory.

Furthermore, a strategy called ‘chunking’ increases the information we can store in our memory and is regularly used by superior memorisers in the World Memory Championships. Chunking involves taking individual units of information (chunks) and grouping them into larger units. For example, rather than learning a phone number as 4-7-1-1-3-2-4, we would chunk it as 471-1324 and remember it more easily. Repetition, though dull and monotonous, also facilitates transforming short-term memories into long term memories.

Over-secretion of cortisol (a stress hormone) has been found to damage the hippocampus, which can result in memory loss

Finally, in order to enhance your memorising ability, it is vital to keep calm and relaxed. Over-secretion of cortisol (a stress hormone) has been found to damage the hippocampus, which can result in memory loss. This is demonstrated in individuals suffering from Post Traumatic Stress Disorder who often cannot remember the traumatic event as a result of the severe stress experienced. Correspondingly, their brain scans reveal a shrunken hippocampus, due to cortisol damage. Of course, the exam period is a stressful time and some anxiety is to be expected, but too much stress is counterproductive, so take time to relax and chill-out.

It seems unlikely that many of us are aspiring to enter the World Memory Championships; rather, we just want to revise efficiently and do well in our exams. However, if mnemonics work so well for ‘superior memorisers’ such as Chao Lu, the world record holder for memorising 67,890 digits of Pi, they’re surely worth giving a try.