Neil: I'm Neil.
Sam: And I'm Sam.
Many people have favourites - a favourite colour,
a favourite flavour, a favourite word.
What's yours, Neil?
Neil: Hmm, my favourite colour is green,
my favourite flavour is sweet-and-sour,
and, well, I don't know if it's my favourite,
but there is a word I really like saying out loud - 'nincompoop'.
It means a silly person.
Sam: For me, it's the taste of coffee,
and the smell of lavender, or freshly baked bread.
Neil: Our favourite tastes, smells and colours are controlled by our five senses -
sight, sound, smell, taste, and touch.
For most of us they don't mix.
We see colours and taste flavours,
but we can't taste sounds.
Sam: But that's not how everyone's brain works.
Imagine being able to 'taste' every word that you hear.
In this programme, we'll meet two sisters from Glasgow in Scotland who can do just that.