Many people see words as colours, smells or sounds, and they swear it boosts their creativity. So could we all tweak our senses to see the world in this way?

Olympia Colizoli doesn’t see the world like you. “To me, all time and numbers are arranged in physical space. Days, weeks, months, years, centuries all have shapes, and I use those shapes to organise my mental plan,” she says. “It took me a long time to realise other people didn't think in this way.”

Colizoli, a cognitive neuroscientist, experiences synaesthesia. Some people with this condition see colours, smells or sounds when they read words. In Colizoli’s case, numbers have a certain size, shape or other physical property. For example, people’s ages are expressed as a curved line. She also happens to study synaesthesia at the University of Amsterdam, curious to know whether she was born with her condition, or whether it was partly learned.

If you could teach yourself to see the world this way, it could potentially boost your creativity. Famous synaesthetes reportedly include Pharrell Williams who sees music in colour (and who told Oprah’s O Magazinehe couldn’t make music without it), and physicist Richard Feynman, who saw letters in equations as colours, and whose visualisation of quantum interactions won him the Nobel Prize.

But could it be possible to train yourself to see the world from a new, multisensory perspective? And if so, would it have the same effect as those to whom it comes naturally?

Musician Pharrell Williams claims his synaesthesia aids his creativity (Getty Images)

Musician Pharrell Williams claims his synaesthesia aids his creativity (Getty Images)

Synaesthesia was first recorded medically by Gustav Fechner in 1812, and since then estimates have put the number of people experiencing the effect at anywhere between 1 in 2,000 and 1 in 23. The difficulty in knowing how many people experience synaesthesia is that like Colizoli, many people do not realise they experience the world any differently to other people. Even defining synaesthesia can be tricky because of the different ways in how people experience it.

To qualify as a synaesthete, the effect needs to be conscious, consistent and automatic. This distinguishes them from hallucinations, says Colizoli, because synaesthetes know that their world of colour or smell is not “real”.

No one is sure what causes synaesthesia, although it does seem to run in families. Colizoli notes that when you find one person who experiences the effect, it’s likely that another family member will report similar symptoms. This is known as developmental synaesthesia, and it differs to injury-related synaesthesia which results from brain damage – such as the man whose stroke left him uncontrollably excited by the James Bond theme tune. Synaesthesia is more common in those on the autistic spectrum, but as a group, synaesthetes do not show a higher prevalence of autism than the general population.

(Purvi Joshi/Getty Images)

(Purvi Joshi/Getty Images)

There’s some tantalising evidence that some aspects of synaesthesia can be learned. In a study carried out by Colizoli and her colleagues at the University of Amsterdam, non-synaesthetic people were given books to read in which the letters e, t, a and s were coloured while the rest of the text was left black. Despite reading the text as normal (and making no concerted effort to remember the colours), the participants began associating those letters with their colour.

Colizoli tested participants by flashing letters of the alphabet and asking them to name the colour the letter was written in. When a letter was written with a different colour to the one it had in the book, it took the participants longer to identify it – a cognitive delay known as the Stroop Effect. So while they weren’t ‘seeing’ colours, they did seem to be beginning to form the basic mental associations of natural synaesthetes.

However, the effect was short-lived. “They forgot the letter-colour pairs after several months,” says Colizoli. “And they did not report experiencing colour upon viewing black letters when reading.”

Memory stick

Natural synaesthesia does seem have an element of learning though – or at least, can sometimes be shaped by memorable experiences. Colizoli recalls a woman who identified each letter as having a distinct colour. One day she visited her elementary school classroom and discovered the brightly-coloured alphabet hanging on the wall matched how she saw letters – in learning to read and write, she may have subconsciously absorbed the colour as well as the shape of the letters. And last year, a study of 11 synaesthetes discovered that the particular colours they associated with letters were “startlingly similar” to those of a very famous Fisher Price fridge magnet alphabet set sold between 1972 and 1989. Ten of the test subjects recalled owning the set, and the 11th beat odds of a billion to one in matching 14 of their colour associations with the fridge magnets. So while these people may have been predisposed to synaesthesia via their genetics, how it manifested may well have been learned in childhood.

(Credit: Thinkstock)

(Credit: Thinkstock)

There’s certainly more to synaesthesia than early childhood memories – otherwise most people in the Western world would likely associate ‘M’ with the colour yellow thanks to McDonald’s ubiquitous golden arches. Why these colour associations take root in some people and not others is still a mystery.

And in any case, those that covet synaesthesia abilities should remember that a colourful, multi-sensory world can sometimes be a problem. Colizoli describes how one child she encountered found it difficult to read, because the black text had a bright associated colour, making it difficult to read against the white paper. Likewise, coloured numbers can prove confounding as well. Two numbers that have associated colours might combine in ways that don't make chromatic sense, so the result of adding a red number to a yellow number might not be an orange number. “My overall impression is that children are more likely to find it distracting compared to adults,” says Colizoli. “I believe adults usually have developed strategies to cope with it.”

I ask Colizoli if she thinks her habit of placing numbers in physical space has helped or hindered her career as a scientist. “I studied maths as an undergraduate and always visualised numbers,” she admits. “But it's a chicken-and-egg situation. Did the maths degree help me visualise numbers, or was it the other way around? It’s hard to say.”

Scientists like Colizoli are still unpicking how much of synaesthesia is genetic and how much is learned. While it appears that a typical person would struggle to train their brain to see a multi-sensory world like natural synaesthetes, there’s some tantalising evidence that elements of the condition can be acquired, at least temporarily. So if you believe your lack of synaesthesia is holding you back creatively, maybe you should try writing your ideas out in colourful pens, or even children’s fridge magnets.

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