On Idioms: Cornerstones for a Neurological Model of Language Processing

The examination of the cognitive and neural correlates of idiom comprehension is an excellent test ground for a neurological model of language processing. Idioms are hybrid linguistic elements: They carry similar to metaphors figurative meanings, but employ also alternative parsing strategies. Here new evidence will be discussed that predicts comprehension of figurative meanings by means of temporal and spatial parameters. Accordingly, an account of the human language system is suggested that divides between a left-sided Core Language System (CLS) and a bilateral Pragmatic Language Network (PLN). Online comprehension of literal and idiomatic phrases seems to take place exclusively in the core language system. Moreover, the computational costs associated with idiom processing seem to be compatible with those costs related to syntactic ambiguity resolution or to syntactic movements. In contrast, creative figurative meanings such as metaphors may be primarily a domain of the bilateral pragmatic language network. Several conclusions will be drawn about the cognitive and neural correlates of language processing.