Why do I See Words and Numbers in my Mind...
Whenever I look at an object I see a word that tells me what that object is and, in more cases than not, a word that describes the color of the object. I have been diagnosed with ADHD by medical professionals. Anyway, when I look at, for example, a jacket, I see the word in my mind: "Jacket." When I see a uniquely colored object, such as a red jacket, I see in my mind: "Red jacket." I don't do this intentionally. When I'm familiar with what an object is or what the name of it is, I'll automatically recall it when I see it.
As for numbers, when I see a group of objects that are the same, I see them as numbered. Of course, this is assuming that there is a reasonable amount of them and that they are not miniscule. Each of them has its own number and I sort them into groups that way. What may be the cause of this?
Source: Mental Help Net Questions and Answers