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The view that words are arbitrary is a foundational assumption about language, used to set human languages apart from nonhuman communication. We present here a study of the alignment between the semantic and phonological structure (systematicity) of American Sign Language (ASL), and for comparison, two spoken languages—English and Spanish. Across all three languages, words that are semantically related are more likely to be phonologically related, highlighting systematic alignment between word form and word meaning. Critically, there is a significant effect of iconicity (a perceived physical resemblance between word form and word meaning) on this alignment: words are most likely to be phonologically related when they are semantically related and iconic. This phenomenon is particularly widespread in ASL: half of the signs in the ASL lexicon areiconicallyrelated to other signs, i.e., there is a nonarbitrary relationship between form and meaning that is shared across signs. Taken together, the results reveal that iconicity can act as a driving force behind the alignment between the semantic and phonological structure of spoken and signed languages, but languages may differ in the extent that iconicity structures the lexicon. Theories of language must account for iconicity as a possible organizing principle of the lexicon.
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Evidence for a Spoken Word Lexicon in the Auditory Ventral Stream
Abstract The existence of a neural representation for whole words (i.e., a lexicon) is a common feature of many models of speech processing. Prior studies have provided evidence for a visual lexicon containing representations of whole written words in an area of the ventral visual stream known as the visual word form area. Similar experimental support for an auditory lexicon containing representations of spoken words has yet to be shown. Using functional magnetic resonance imaging rapid adaptation techniques, we provide evidence for an auditory lexicon in the auditory word form area in the human left anterior superior temporal gyrus that contains representations highly selective for individual spoken words. Furthermore, we show that familiarization with novel auditory words sharpens the selectivity of their representations in the auditory word form area. These findings reveal strong parallels in how the brain represents written and spoken words, showing convergent processing strategies across modalities in the visual and auditory ventral streams.
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- Award ID(s):
- 1756313
- PAR ID:
- 10413875
- Publisher / Repository:
- DOI PREFIX: 10.1162
- Date Published:
- Journal Name:
- Neurobiology of Language
- Volume:
- 4
- Issue:
- 3
- ISSN:
- 2641-4368
- Page Range / eLocation ID:
- p. 420-434
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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