I was eight years old, having chips and coke in a cafe in Glasgow, when my auntie Jackie announced she was pregnant and asked my little sister, Jen, and I if we liked the name Sarah. We looked at each other in disgust. “But Sarah tastes like greasy chips,” we roared. Jackie looked at us bewildered, but it was obvious to us: “Everything tastes,” we kept telling her. “Everything tastes!”

I didn’t have the language to tell her that my sister and I have a neurological quirk named ‘synaesthesia’, which means our minds attribute a flavour or sensation to every name and place. Synaesthesia is a blending of the senses, related to the way signals in  the brain are processed. Our mum has it too, but hers is more vague. It affects less than per cent of the population, although some experience it as a visual or hearing-related quirk, such as associating a word with a colour or musical note. Mine is 90 per cent taste, sometimes sensations or images.

As kids, my sister and I enjoyed our party trick. We’d sit at Gran’s kitchen table asking each other: “What’s Sally to you?” Or Michael. Or some other kid at school. My auntie never had a Sarah. She had two boys, Scott, who tastes like a McVitie’s Rich Teabiscuit snapped in two, and Jack, like chomping on a battered leather footstool.

It wasn’t until my late twenties that I realised how unusual it was to possess this extra sense. I was working as an employment adviser, and used my synaesthesia to entertain the others in the office. We’d scroll through the staff intranet and say, “He’s a big jam tart” or “She’s a sweaty shoelace.”

It’s a completely instant thing; getting to know someone’s personality can’t alter the way I taste their name. Sadly, Julie is a watery eyeball. David (my husband’s name) is the damp sand of Blackpool beach with a little coloured spade stuck in it. My niece, Sophia, is pink foam shrimps and her brother Leo is thick custard. Donald is a rubber duck dipped in vinegar. Dawn and Donna are similar, so there must be something in the letter combinations.

At thirty-eight, I’m getting to the age where friends are having babies and they often run names by me, although I’m not aware of it affecting anyone’s choice. I don’t think I want children but if I did, synaesthesia would play a part in choosing a name. Edward makes me feel like I’m ruffling a small man’s hair, but he has dandruff. Pamela is the sensation of squeezing a My Little Pony’s bottom.

It also works with place names. Glasgow is washed windows, with soapsuds dripping down the panes; London is the tinkle of the bell the altar boy rings in Catholic mass. By comparison, words such as ‘chocolate’ or ‘dog’ tend to provoke a predictable sensual response: I will taste chocolate or smell a dog’s coat. Other words have no automatic associations, but can sometimes provoke a taste too, as they allow my mind to wander. Brexit is a snapped KitKat; Remain is a Jammie Dodger.

With synaesthesia, each person experiences it differently. My sister has additional layers. She attributes personalities and genders to numbers and letters. For example, nine is a boy and numbers seven and eight fancy each other. My synaesthesia isn’t intrusive; I have to tune into it.

I’m glad I discovered my synaesthesia thirty years ago. If someone offered me a pill that took it away I’d say, “No, thank you.” It’s like having another sense; not a very important one, but it makes life more fun.