Here's a semiotics text that speaks of the gap or interval between images and words in the media:


Word and Image:
the Interval, Precession and Reciprocal Transgression
Pietro Montani
University of Rome "La Sapienza"
The hypothesis that I would like to discuss is as follows: whether the relationship between image and language, in all of its forms, should be considered the result of relations between two systems or if it would not be more advantageous and appropriate - for the very reason of better understanding the effects of discourse - to concentrate one's attention on the relationship itself, on its origins and its conditions.
Let me clarify my point, to avoid seeming to have opened with some sort of tautology. I would like to suggest that in order to adequately understand the phenomenon of interference between image and language (for example, audio-visual media) it might be useful and even advantageous to consider the relationship itself as something more original than its component parts.
This is what I mean when I speak of "interval". There is an intermediate space, leftover between word and image, a gap that belongs neither to the verbal nor the iconic although of necessity having a bit of each
http://www.hum.au.dk/semiotics/docs/epub/urb97/Montani.htm