LEFT hemisphere dominance for language (in right-handers) is the most wellestablished instance of division of labour between the cerebral hemispheres (cf. Geschwind, 1970; Luria, 1970; Milner, Branch and Rasmussen, 1964). However, this characterization rests almost entirely on studies probing the appreciation of language in its literal, denotative aspects (Jakobson, 1960). Whether the left hemisphere dominance for language extends as well to other, more figurative, uses has not been established.

The ability to transcend literal meanings proves essential in normal language use. For instance, in all languages, terms used to refer to psychological aspects of experience are drawn from the physical world (for example, a hard heart; adry wit)(Asch, 1955). In a similar fashion, percepts drawn fronra particular sensory modality are described by terms drawn, synaesthetically, from another sensory domain (for example, a loud colour; a bright smell)(Williams, 1976). Where linguistic performance relies on only the primary denotative senses of words, communication is not only severely impoverished but, in many cases, actually prohibited.