Non-Local Conceptual Combination

Abstract

It is uncontroversial that the syntax of an expression largely determines its meaning. For example, there is no way to interpret a sentence like "the blue hat has a white bow" as telling you that there is a white hat that has blue bow. But to what extent are the brain's combinatory interpretive routines exclusively locked into the structures given by syntax? Consider another example: "The blue color of his hat is pretty." This sentence tells us that a color is pretty, that the color is blue and that the color belongs to a hat. What the syntax of this sentence does not give us is a combination of "blue" and "hat." But clearly, if we were to draw a picture of the meaning of this sentence, it would have a blue hat in it. We asked: upon encountering "hat" in this sentence, do our brains combine the features of "blue" with the features of "hat," despite the long distance between them and no direct syntactic relation? By using a known neural measure of conceptual combination in the left anterior temporal lobe, we obtained evidence using MEG that our brains appear to perform such a long-distance conceptual combination that does not track the syntax. Intriguingly, word (or rather concept) order affected the directionality of the effect. While the effect of concept order remains a topic for future work, our results overall suggest that the meaning composition system of language is likely richer than the combinatory steps predicted from syntactic structures.