You may have been brought up to avoid thinking rude thoughts.
But they could actually keep your mind sharp and help you remember facts, one expert claims.
The Grand Master of Memory, Ed Cooke, says that rude and violent thoughts are more memorable and can be linked with other information to help you recall it.
‘Vivid, meaningful experiences are obviously more memorable than boring,’ he told MailOnline.
Mr Cooke explained that sexual thoughts evoke emotion, and guarantee interest.
‘A great rule of thumb for what’s memorable is “whatever would grab your attention as you’re wandering down the street will grab your attention when you’re looking for a memory".
‘Nakedness, things that are taboo, extremely attractive people, things we intrigued by: these will grab your attention in the world, and memories that have these elements will also stick out.’
For example, school boys have long dreamt up dirty rhymes to remember facts for exams, but such a strategy was originally used by the ancient Greeks and Romans.
HOW TO MEMORISE A DECK OR CARDS
You may think that you’re not capable of memorising a pack of cards in order or a series of 1,000 numbers, but Mr Cooke claims it’s all about practice.
‘Learning a number sequence (3.14159265358979, for instance) is intimidating for two reasons. One, the digits themselves are meaningless and tricky to remember and two, the sequence, unlike a good story, for instance, is random and also therefore unmemorable.’
To give it a go, he suggests breaking the numbers up into small groups that are more manageable, for example, 3.14 / 15 / 92 / 653 / 5 / 89 79.
He then said people should find links to the small groups of numbers that are full of meaning.
‘We all know 3.14 is how pi begins,’ Mr Cooke said. ‘Next you might think of 15/92 as a 15 year old girl with her 92 year-old grandpa. 653 5 could be England scoring 653 for 5 declared against the Aussies (if you’re into cricket).
‘Then you might link 89 / 79 to the idea of an 89 year old man with his 79 year old wife. Ages work well. Pay attention to the jumps: it’s a ten year difference in that case.’
He says that we can overcome the problem of numbers seeming unmemorable and random, by stringing the images into a story.
For example, ‘after eating some pie (3.14) 15 year old Jennie runs out of her home to find 92 year-old grandpa mowing the lawn. They turn on the radio to hear that England just declared on 653 for 5. Hoorah! Meanwhile, grandpa’s neighbours - a couple aged 89 and 79 - are wandering down the street and say hello, etc’.
A poet called Simonides who lived between 556 and 468 BC, first worked out that transforming information into a sequence of memorable images is an effective way of recalling them.
Techniques were used to remember poetry as well as political and legal debates. Cicero, for example, used surprising violent or sexual imagery to make this process even easier.
‘The Rhetorica ad Herennium - a text on rhetoric by an unknown author that was once attributed to Cicero - carries the example of a lawyer forming an image to remind himself to mention the testimony of a witness,’ Mr Cooke explained.
‘To imprint this memory, he imagines a ram’s testicles - in Latin, testiculi suggests testes or witnesses - on the fourth finger of a hand.
‘This revolting, easily imagined image is, as one can imagine, a hundred times more memorable than the word “witness.”’
He said that it’s not just dirty thoughts that help people remember details more easily.
Colour, movement, violence, humour, absurdity, and things which we are personally interested in can all be used as memory prompts.
Mr Cooke first became interested in memory when he was hospitalised for three months and learned memory recall techniques.
He went on to study psychology at the University of Oxford and became a grand master of memory at the age of 23, having recalled 1,000 numbers in an hour and memorised a shuffled deck of cards within two minutes.
‘Memory isn’t mysterious. We’ve evolved to be good at remembering what we’re interested in,’ he said.
Mr Cooke developed a website called Memrise to help people more easily remember facts for exams and language vocabulary. It has two-and-a-half million users and aims to turn learning into a game of the imagination.
He believes that people’s memory can get better with age – not worse.
‘There’s a general tendency for people to think that their memory is in decline but it’s exaggerated, he said.’
'There’s a string cultural narrative to suggest that memory gets worse as you get older. People interpret memory errors due to a failing brain, so distraction is interpreted as forgetting.
‘In fact, vocabulary grows with age and you have a larger set of experiences to connect to new knowledge.’
He explains that older people are more inclined to pronounce unusual surnames correctly, for example, because they are more likely to encounter them before, just as they can link more experiences to new information, enabling them to learn more easily.
A study by researchers at New York University, conducted in 1996, claimed that old age is all in the mind.
Participants were asked to remember a list of words including age-related terms such as ‘grey’ and ‘bingo’ and after the exercise, they left the room more slowly than people who thought about non-age related words.
The findings suggest that the expectation of moving slowly when people become old, is enough to make people sluggish.
Mr Cooke, who was not involved with the study, said: ‘You can see how this relates to memory. ‘If you and others expect your memory to get worse, you’ll interpret your failures as signs of mental decay.
‘The same experience in a young person would be interpreted differently, and lead to different long-term performance. So the idea of age-related decline can be a self-fulfilling prophecy.’
The master of memory said people can do simple mental exercises such as Suduko or crosswords, learn language or something new, to stop the narrative taking over.
Many of the grand masters of memory are middle aged. Dominic O’Brien is one of the most accomplished.
He can remember incredibly long lists of numbers, such as 4,140 binary digits in 30 minutes,132 historical dates in 5 minutes and 1,456 shuffled playing cards (28 packs) in one hour.
Mr Cooke says anyone can achieve such amazing feats of memory with practice.
‘Everyone is capable of this…Memorising facts is like riding a bicycle of the brain it’s using simple strategies to amplify efficiencies.
Mr O’Brien proved that memory doesn’t naturally deteriorate with age – except from a neurological disorder – by putting his reputation on the line.
In 1991 at the age of 34, he became the very first World Memory Champion in a gruelling competition comprised of tasks to test the memory to its extremes.
Then, after a nine year break, he entered the warm up competition to the World Championships at the age of 55 to test if he still had what it takes to remember vast reams of information.
Surprising himself, Mr O’Brien recorded personal bests in almost all disciples. He believes that everyone has a better memory than they think they have, no matter what age they are.
All we lack is a grasp of simple techniques and a bit of practice. He said: ‘With every physical or mental skill, if we don’t use it, we lose it.’
‘In the World Memory Championships none of the competitors taking part were born with particularly good memories. For all of them, this is a skill they have developed by learning the techniques and doing lots of practice – just like any other sport.’
In collaboration with University College London (UCL), Memrise has launched a prize to discover the most effective way to learn information in an hour, which could transform the way people learn.
‘Lots of research has been done but the perfect combination has yet to be found.’ Mr Cooke said, adding that anyone can enter the competition, which has a prize of $10,000 (£6,380).
The closing date for entries is February 28, 2015 and the winner will be announced on May 31.