What makes words special? Words as unmotivated cues

Verbal labels, such as the words "dog" and "guitar," activate conceptual knowledge more effectively than corresponding environmental sounds, such as a dog bark or a guitar strum, even though both are unambiguous cues to the categories of dogs and guitars (Lupyan & Thompson-Schill, 2012). We hypothesize that this advantage of labels emerges because word-forms, unlike other cues, do not vary in a motivated way with their referent. The sound of a guitar cannot help but inform a listener to the type of guitar making it (electric, acoustic, etc.). The word "guitar" on the other hand, can leave the type of guitar unspecified. We argue that as a result, labels gain the ability to cue a more abstract mental representation, promoting efficient processing of category members. In contrast, environmental sounds activate representations that are more tightly linked to the specific cause of the sound. Our results show that upon hearing environmental sounds such as a dog bark or guitar strum, people cannot help but activate a particular instance of a category, in a particular state, at a particular time, as measured by patterns of response times on cue-picture matching tasks (Exps. 1-2) and eye-movements in a task where the cues are task-irrelevant (Exp. 3). In comparison, labels activate concepts in a more abstract, decontextualized way-a difference that we argue can be explained by labels acting as "unmotivated cues".