It was in my notes, but time ran short and I forgot to circle back to it. Then several friends who listened to the show asked me the same question. I had to get the answer. My guest Amar Latif of Traveleyes was so kind to help me out after the fact. Here was my question and Amar's thoughtful answer:
What is the difference in experience between sight-impaired travelers who have never had sight and those who have some memory of sight before losing it?
"With our blind travelers, we have a real mix of those that have never had sight and those that have lost their sight. Some travelers who have never had sight still like to be told about colours and shades, as they can equate colours with emotions or senses that they have. For example, they may associate the colour green with the smell of cut grass, or the colour red with feeling warm.
On the other hand, some travelers who have never had sight may prefer to just have things like shapes and more tangible descriptions, as colours don't hold as much significance. It really does depend on the individual.
Our travelers that have lost their sight in later life often prefer lots of description, as they still have strong visual memories that they can equate to the descriptions. Having lost my sight as a teenager, I love having things described to me so I can build a picture of something in my head. It's the same as reading a book - there are no images but you build a mental picture in your head."