Semantics
Semantic studies of the relationship between words and images investigate the contribution of the pictorial and the verbal elements in the combination of both to a complex message. Most studies of word-image relationships have been concerned with such questions, and therefore I can restrict myself to a typology of word-image relationships from the semantic point of view. Five kinds of relationships between pictures and words in texts can be distinguished: complementarity, dominance, redundancy, discrepancy and contradiction.
Complementary is the ideal mode of combining words and pictures. Word and image are complementary when both are equally necessary to the understanding of the message.
Dominance can mean dominance of the picture, as in books on paintings, or dominance of text, as in illustrations of a novel.
Redundancy is the extreme counterpart of dominance. In the context of a picture, a verbal message is redundant when it only repeats what you see anyhow.
Discrepancy and contradiction are forms of mistaken or poetically deviant word-image combination. Word and image do not fit together. The text and the picture are juxtaposed by editorial negligence, a mistake of the reader, who does not see that both do not belong together, or because of a poetic device with the aim of creating a surprising contradiction between the verbal and the pictorial messages in order to make the reader think further about a possible solution of this enigmatic contradiction.

Pragmatics
While syntactic and semantic aspects of text-picture relationships have been investigated in many studies, less attention has been given to the pragmatic aspects of this relationship. When words are used to direct the readers' attention to the picture, especially to certain parts of it, or when pictures are used to direct the readers' attention to a specific verbal message, the word-image relationship is predominantly a pragmatic one. Prototypical of a pragmatic word-image relationship is a verbal message that says "Look at the upper right hand corner of this picture", or a picture that draws the readers' attention to, and arouses their interest in, an otherwise rather dull verbal message, as in advertising. The relationship between word and picture is in both cases an indexical one.
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