Idiom comprehension in aphasia: Literal interference and abstract representation.

We investigate three potential mechanisms underlying the deficit in idiom comprehension seen in aphasia: difficulty inhibiting literal meanings, inability to recognize that a figurative interpretation is required, and difficulty processing abstract words and concepts. Unimpaired adults and PWA read high and moderate familiarity idioms either preceded or followed by a figuratively biasing context sentence. They then completed a string-to-word probe selection task, choosing between a figurative target, a literal lure, and unrelated concrete and abstract lures. PWA chose the figurative target more often for more familiar idioms and after figuratively biasing contexts, suggesting that difficulty accessing figurative meanings may be a key contributor to idiom impairment in aphasia. Importantly, PWA chose abstract lures at the same rate as they chose literal lures, suggesting that abstract lures may be considered equally good matches for weak idiomatic representations in PWA, and therefore that idiomatic figurative meanings may be represented similarly to abstract concepts for PWA. These results have implications for models of idiom comprehension in aphasia, as well as the design of future studies of idiom comprehension in PWA.