Prof. Karen Emmorey | Neural effects (and non-effects) of iconicity in sign language

Language is fundamental to our species, and yet almost everything we know is based on the study of spoken languages. In comparison to spoken languages, sign languages are much more strongly grounded in the body, as evidenced by the pervasive iconicity observed for these languages (e.g., the form of verbs often depicts an aspect of the denoted action). To investigate the neural response to iconic signs, our research team utilized event-related potentials (ERPs) in conjunction with our database of 1000 American Sign Language (ASL) signs rated for iconicity. We examined whether iconic signs exhibit distinct neural signatures for deaf signers, as well as for hearing ASL learners. Results from a series of experiments reveal that there is no “neural signature” that tracks with the strength of iconicity during sign recognition for deaf signers; however, iconicity impacts the neural response during lexical access for novice ASL learners (but not deaf signers) in a translation priming paradigm. For deaf signers, neural effects of iconicity are found in picture-naming and picture-matching tasks, particularly when there is a structural alignment between the ASL sign and the picture (e.g., the ASL sign BIRD depicts a bird’s beak and aligns with a picture of a bird with a prominent beak, but not with a picture of a bird in flight). Overall, the results reveal neural consequences for grounding language in the body that may only occur under certain circumstances (i.e., when visual features of a picture map to iconic features of a sign).

Poster