Russian–born abstract painter Kandinsky is the artist most commonly thought of as having had synaesthesia – despite the lack of medical proof.

Many other artists have the harmless neurological condition and will see sounds in their mind as colours or shapes. They might not, of course, know it is recognised by medical practitioners.

David Hockney said his ballet and opera set–designs were based on colours he saw while listening to the music of the piece he was working on.

And talking to an interviewer about music, rapper and producer Pharrell Williams said, “It just always stuck out in my mind, and I could always see it. I don't know if that makes sense, but I could always visualize what I was hearing... Yeah, it was always like weird colours.”

Brighton artist Philippa Stanton sees sound, taste and smell in shape, colour and texture. She says it allows her to make portraits of people’s voices, food and drink.

Lewes–based artist and contemporary abstract painter Alex Grey calls her synaesthesia “a crossover between sound and vision”. She hears soundas colours or shapes or as a visual sensation.

Speaking to The Guide before her debut solo show opens at Lewes’ Hop Gallery, she explains, “It is not intrusive. It is not that a song comes on the radio and suddenly I can’t see anything but blue. It is an emotional thing. It’s that crossover area between neurology and psychology.”

Before she turned to art full–time (only a year and a half ago to fulfil a New Year’s resolution), Grey worked in theatre. After training at London’s Goldsmiths College, she worked as a lighting and special effects designer for Walt Disney in Paris, the San Francisco Opera and London’s Imperial War Museum.

There is not much crossover from those days to her current work – though she compares Maiden Voyage, opening tomorrow, to a son et lumière show, thanks to “its blending of sound and colour and creating a spectacle”.

Grey is not a complete novice in front of a canvas. She’s been making abstract works in oil pastel for more than 20 years which is why she’s been granted a solo show so early in her professional artistic life.

It follows her work being included in Surface at The Ark in Basingstoke, the Summer Salon at Islington Arts Factory and Enfield’s Dugdale Gallery Summer Exhibition.

For Lewes’ Hop Gallery, Grey has made 20 works responding to music by musicians including Herbie Hancock, Nick Drake, Leonard Bernstein, Suzanne Vega and Joanna Newsom as well as film soundtracks and field recordings.

To create a multisensory experience an MP3 player and a pair of headphones will be next to each painting so visitors can listen while they look.

“I’m really interested to know how many people will say, ‘oh yeah, of course, it’s blue’ or if people will say, ‘I don’t get it. I don’t see what you’re seeing’.”

Since starting to show her work regularly she’s met others who have the same experiences, similar experiences with different senses, people who see colour in relation to tastes and colour in relation to words.

“Even different days of the week have a colour,” she says. “There is quite a lot of consensus Monday is yellow.”

Many people are affected by it, she says, and Maiden Voyage might spark a light.

“I didn’t realise that everybody didn’t have this for a long time, so one of things I am quite interested in doing with my pictures is seeing how much consensus there is.”

Maiden Voyage: Hop Gallery, Star Brewery, Fisher Street, Lewes, until August 17