Research on the language acquisition of deaf individuals who are exposed to accessible linguistic input at a variety of ages has provided evidence for a sensitive period of first language acquisition. Recent studies have shown that deaf individuals who first learn language after early childhood, late first-language learners (LL1), do not comprehend reversible Subject-Verb-Object (SVO) sentences. The present study analyzed 478 signed productions elicited with pictures depicting simple events with one or two arguments by 28 signers. The argument order patterns of native signers converged with one another and the word order patterns of American Sign Language (ASL). By contrast, the ordering patterns of the LL1 signers did not converge with one another or with the patterns of the native signers. This indicates that early childhood is a period of heightened sensitivity to basic word order and may help explain why complex structures are difficult for LL1 signers to learn.

Bilinguals activate both of their languages as they process written words, regardless of modality (spoken or signed); these effects have primarily been documented in single word reading paradigms. We used eye-tracking to determine whether deaf bilingual readers (n = 23) activate American Sign Language (ASL) translations as they read English sentences. Sentences contained a target word and one of the two possible prime words: a related prime which shared phonological parameters (location, handshape or movement) with the target when translated into ASL or an unrelated prime. The results revealed that first fixation durations and gaze durations (early processing measures) were shorter when target words were preceded by ASL-related primes, but prime condition did not impact later processing measures (e.g., regressions). Further, less-skilled readers showed a larger ASL co-activation effect. Together, the results indicate that ASL co-activation impacts early lexical access and can facilitate reading, particularly for less-skilled deaf readers.

Little is known about the neural changes that accompany sign language learning by hearing adults. We used ERPs and a word-sign matching task to assess how learning impacted the N400 priming effect (reduced negativity for translations compared to unrelated trials). English monolinguals (N = 32) learned 100 ASL signs – half highly iconic (meaning was guessable), half non-iconic. In contrast to non-iconic signs, little learning was needed for the highly iconic signs as translation accuracy was similar pre- and post-learning. Prior to learning, an N400 priming effect was observed only for iconic signs. After learning, the size of the priming effect increased for non-iconic signs (replicating word learning studies) but decreased for iconic signs. For deaf ASL signers (N = 20), iconicity did not modulate the size of the N400 priming effect. We conclude that the impact of iconicity on lexico-semantic processing is reduced following learning, as signs are integrated into an emerging visual-manual lexicon.

Across sign languages, nouns can be derived from verbs through morphophonological changes in movement by (1) movement reduplication and size reduction or (2) size reduction alone. We asked whether these cross-linguistic similarities arise from cognitive biases in how humans construe objects and actions. We tested nonsigners’ sensitivity to differences in noun–verb pairs in American Sign Language (ASL) by asking MTurk workers to match images of actions and objects to videos of ASL noun–verb pairs. Experiment 1a’s match-to-sample paradigm revealed that nonsigners interpreted all signs, regardless of lexical class, as actions. The remaining experiments used a forced-matching procedure to avoid this bias. Counter our predictions, nonsigners associated reduplicated movement with actions not objects (inversing the sign language pattern) and exhibited a minimal bias to associate large movements with actions (as found in sign languages). Whether signs had pantomimic iconicity did not alter nonsigners’ judgments. We speculate that the morphophonological distinctions in noun–verb pairs observed in sign languages did not emerge as a result of cognitive biases, but rather as a result of the linguistic pressures of a growing lexicon and the use of space for verbal morphology. Such pressures may override an initial bias to map reduplicated movement to actions, but nevertheless reflect new iconic mappings shaped by linguistic and cognitive experiences.

A growing body of research shows that both signed and spoken languages display regular patterns of iconicity in their vocabularies. We compared iconicity in the lexicons of American Sign Language (ASL) and English by combining previously collected ratings of ASL signs (Caselli, Sevcikova Sehyr, Cohen-Goldberg, & Emmorey, 2017) and English words (Winter, Perlman, Perry, & Lupyan, 2017) with the use of data-driven semantic vectors derived from English. Our analyses show that models of spoken language lexical semantics drawn from large text corpora can be useful for predicting the iconicity of signs as well as words. Compared to English, ASL has a greater number of regions of semantic space with concentrations of highly iconic vocabulary. There was an overall negative relationship between semantic density and the iconicity of both English words and ASL signs. This negative relationship disappeared for highly iconic signs, suggesting that iconic forms may be more easily discriminable in ASL than in English. Our findings contribute to an increasingly detailed picture of how iconicity is distributed across different languages.

Iconicity is often defined as the resemblance between a form and a given meaning, while transparency is defined as the ability to infer a given meaning based on the form. This study examined the influence of knowledge of American Sign Language (ASL) on the perceived iconicity of signs and the relationship between iconicity, transparency (correctly guessed signs), ‘perceived transparency’ (transparency ratings of the guesses), and ‘semantic potential’ (the diversity (H index) of guesses). Experiment 1 compared iconicity ratings by deaf ASL signers and hearing non-signers for 991 signs from the ASL-LEX database. Signers and non-signers’ ratings were highly correlated; however, the groups provided different iconicity ratings for subclasses of signs: nouns vs. verbs, handling vs. entity, and one- vs. two-handed signs. In Experiment 2, non-signers guessed the meaning of 430 signs and rated them for how transparent their guessed meaning would be for others. Only 10% of guesses were correct. Iconicity ratings correlated with transparency (correct guesses), perceived transparency ratings, and semantic potential (H index). Further, some iconic signs were perceived as non-transparent and vice versa. The study demonstrates that linguistic knowledge mediates perceived iconicity distinctly from gesture and highlights critical distinctions between iconicity, transparency (perceived and objective), and semantic potential.

Previous studies suggest that age of acquisition affects the outcomes of learning, especially at the morphosyntactic level. Unknown is how syntactic development is affected by increased cognitive maturity and delayed language onset. The current paper studied the early syntactic development of adolescent first language learners by examining word order patterns in American Sign Language (ASL). ASL uses a basic Subject–Verb–Object order, but also employs multiple word order variations. Child learners produce variable word order at the initial stage of acquisition, but later primarily produce canonical word order. We asked whether adolescent first language learners acquire ASL word order in a fashion parallel to child learners. We analyzed word order preference in spontaneous language samples from four adolescent L1 learners collected longitudinally from 12 months to six years of ASL exposure. Our results suggest that adolescent L1 learners go through stages similar to child native learners, although this process also appears to be prolonged.

No previous research has investigated the neural correlates of vocabulary acquisition in second language learners of sign language. The present study investigated whether poor vocabulary knowledge engaged similar prefrontal lexico-semantic regions as seen in unimodal L2 learners. Behavioral improvements in vocabulary knowledge in a cohort of M2L2 learners were quantified. Results indicated that there is significant increase in vocabulary knowledge after one semester, but stabilized in the second semester. A longitudinal fMRI analysis was implemented for a subset of learners who were followed for the entire 10 months during initial sign language acquisition. The results indicated that learners who had poor sign vocabulary knowledge consistently showed greater activation in regions involved in motor simulation, salience, biological motion and spatial processing, and lexico-semantic retrieval. In conclusion, poor vocabulary knowledge requires greater engagement of modality-independent and modality-dependent regions, which could account for behavioral evidence of difficulty in visual phonology processing.

This study investigated the structure of the bimodal bilingual lexicon. In the cross-modal priming task nonnative sign language learners heard an English word (e.g., keys) and responded to the lexicality of a signed target: an underlying rhyme (e.g., cheese) or a sign neighbor of that word (e.g., paper). The results indicated that rhyme words were retrieved more quickly and the L2 neighbors were faster for beginner learners. An item analysis also indicated that semantics did not facilitate neighbor retrieval and high frequency signs were retrieved more quickly. The AX discrimination task showed that learners focus on handshape and movement parameters and discriminate equally. The interlanguage dynamics play an important role in which phonological parameters are used and the spread of activation over time. A nonselective, integrated model of the bimodal bilingual lexicon is proposed such that lateral connections are weakened over time and handshape parameter feeds most of the activation to neighboring signs as a function of system dynamics.

Spoken language (unimodal) interpreters often prefer to interpret from their non-dominant language (L2) into their native language (L1). Anecdotally, signed language (bimodal) interpreters express the opposite bias, preferring to interpret from L1 (spoken language) into L2 (signed language). We conducted a large survey study (N = 1,359) of both unimodal and bimodal interpreters that confirmed these preferences. The L1 to L2 direction preference was stronger for novice than expert bimodal interpreters, while novice and expert unimodal interpreters did not differ from each other. The results indicated that the different direction preferences for bimodal and unimodal interpreters cannot be explained by language production–comprehension asymmetries or by work or training experiences. We suggest that modality and language-specific features of signed languages drive the directionality preferences of bimodal interpreters. Specifically, we propose that fingerspelling, transcoding (literal word-for-word translation), self-monitoring, and consumers’ linguistic variation influence the preference of bimodal interpreters for working into their L2.

Given that the linguistic articulators for sign language are also used to produce co-speech gesture, we examined whether one year of academic instruction in American Sign Language (ASL) impacts the rate and nature of gestures produced when speaking English. A survey study revealed that 75% of ASL learners (N = 95), but only 14% of Romance language learners (N = 203), felt that they gestured more after one year of language instruction. A longitudinal study confirmed this perception. Twenty-one ASL learners and 20 Romance language learners (French, Italian, Spanish) were filmed re-telling a cartoon story before and after one academic year of language instruction. Only the ASL learners exhibited an increase in gesture rate, an increase in the production of iconic gestures, and an increase in the number of handshape types exploited in co-speech gesture. Five ASL students also produced at least one ASL sign when re-telling the cartoon. We suggest that learning ASL may (i) lower the neural threshold for co-speech gesture production, (ii) pose a unique challenge for language control, and (iii) have the potential to improve cognitive processes that are linked to gesture.

According to some discussions concerning new information technologies and technologically enhanced communication, we are now in a revolution as profound as the printing press. The Internet is creating new kinds of meetingplaces and work areas and the possibilities of new types of relationships across time and space. This article reports on some ways that the Internet is shaping language practices in the Deaf community, with an interest in how new tools mediate and influence human behavior, including language and the organization of interaction. This includes the development and manipulation of a computer-mediated image of self and other, creativity and problem-solving in new communicative spaces, creating reciprocal perspectives, new participation frameworks, and specifics of language change. For the first time, deaf people can communicate using manual visual language, in many cases their native language, across space and time zones. This groundbreaking situation makes the Deaf community a particularly productive site for research into relationships between technological innovations and new communicative practices.