Joshua T. Williams

Interlanguage dynamics and lexical networks in nonnative L2 signers of ASL: cross-modal rhyme priming

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.

Impacts of Visual Sonority and Handshape Markedness on Second Language Learning of American Sign Language.

The roles of visual sonority and handshape markedness in sign language acquisition and production were investigated. In Experiment 1, learners were taught sign-nonobject correspondences that varied in sign movement sonority and handshape markedness. Results from a sign-picture matching task revealed that high sonority signs were more accurately matched, especially when the sign contained a marked handshape. In Experiment 2, learners produced these familiar signs in addition to novel signs, which differed based on sonority and markedness. Results from a key-release reaction time reproduction task showed that learners tended to produce high sonority signs much more quickly than low sonority signs, especially when the sign contained an unmarked handshape. This effect was only present in familiar signs. Sign production accuracy rates revealed that high sonority signs were more accurate than low sonority signs. Similarly, signs with unmarked handshapes were produced more accurately than those with marked handshapes. Together, results from Experiments 1 and 2 suggested that signs that contain high sonority movements are more easily processed, both perceptually and productively, and handshape markedness plays a differential role in perception and production.

Modality-independent neural mechanisms for novel phonetic processing.

The present study investigates whether the inferior frontal gyrus is activated for phonetic segmentation of both speech and sign. Early adult second language learners of Spanish and American Sign Language at the very beginning of instruction were tested on their ability to classify lexical items in each language based on their phonetic categories (i.e., initial segments or location parameter, respectively). Conjunction analyses indicated that left-lateralized inferior frontal gyrus (IFG), superior parietal lobule (SPL), and precuneus were activated for both languages. Common activation in the left IFG suggests a modality-independent mechanism for phonetic segmentation. Additionally, common activation in parietal regions suggests spatial preprocessing of audiovisual and manuovisual information for subsequent frontal recoding and mapping. Taken together, we propose that this frontoparietal network is involved in domain-general segmentation of either acoustic or visual signal that is important to novel phonetic segmentation.

Modality-Independent Effects of Phonological Neighborhood Structure on Initial L2 Sign Language Learning

Abstract The goal of the present study was to characterize how neighborhood structure in sign language influences lexical sign acquisition in order to extend our understanding of how the lexicon influences lexical acquisition in both sign and spoken languages. A referent-matching lexical sign learning paradigm was administered to a group of 29 hearing sign language learners in order to create a sign lexicon. The lexicon was constructed based on exposures to signs that resided in either sparse or dense handshape and location neighborhoods. The results of the current study indicated that during the creation of the lexicon signs that resided in sparse neighborhoods were learned better than signs that resided in dense neighborhoods. This pattern of results is similar to what is seen in child first language acquisition of spoken language. Therefore, despite differences in child first language and adult second language acquisition, these results contribute to a growing body of literature that implicates the phonological features that structure of the lexicon is influential in initial stages of lexical acquisition for both spoken and sign languages. This is the first study that uses an innovated lexicon-construction methodology to explore interactions between phonology and the lexicon in L2 acquisition of sign language.

Spoken Language Activation Alters Subsequent Sign Language Activation in L2 Learners of American Sign Language

A large body of literature has characterized unimodal monolingual and bilingual lexicons and how neighborhood density affects lexical access; however there have been relatively fewer studies that generalize these findings to bimodal (M2) second language (L2) learners of sign languages. The goal of the current study was to investigate parallel language activation in M2L2 learners of sign language and to characterize the influence of spoken language and sign language neighborhood density on the activation of ASL signs. A priming paradigm was used in which the neighbors of the sign target were activated with a spoken English word and compared the activation of the targets in sparse and dense neighborhoods. Neighborhood density effects in auditory primed lexical decision task were then compared to previous reports of native deaf signers who were only processing sign language. Results indicated reversed neighborhood density effects in M2L2 learners relative to those in deaf signers such that there were inhibitory effects of handshape density and facilitatory effects of location density. Additionally, increased inhibition for signs in dense handshape neighborhoods was greater for high proficiency L2 learners. These findings support recent models of the hearing bimodal bilingual lexicon, which posit lateral links between spoken language and sign language lexical representations.

Connections between Fingerspelling and Print: The Impact of Working Memory and Temporal Dynamics on Lexical Activation

Recently there has been a renewed interest in characterizing the role of fingerspelling for deaf readers. The present study takes a step back and creates a theoretical foundation for investigating similarities between fingerspelling and print decoding in hearing signers. In this way, we can probe the constraints of temporal processing and memory on L1 orthography and the processing of L2 fingerspelling. Using a cross-modal priming paradigm, the role of orthography and phonology in print and fingerspelling word recognition was investigated. Results indicate significant inhibition in target retrieval when the prime was fingerspelled but not when it was presented in print. It was hypothesized that inhibition was due to either recoding or prime temporal dynamics. Hearing nonsigners were tested with serially or simultaneously presented print to determine the role of recoding and temporal dynamics. The results suggest that: (1) difficulties in processing fingerspelling for L2 learners might arise from recoding back into an L1 orthographic representation; (2) working memory abilities may reduce inhibition caused by recoding in L2 learners; (3) serial presentation of an orthographic code, either manual or visual, reduces priming effects; and (4) letter position differences provide evidence of depletion of activation over time.

Phonological substitution errors in L2 ASL sentence processing by hearing M2L2 learners

In the present study we aimed to investigate phonological substitution errors made by hearing second language (M2L2) learners of American Sign Language (ASL) during a sentence translation task. Learners saw sentences in ASL that were signed by either a native signer or a M2L2 learner. Learners were to simply translate the sentence from ASL to English. Learners’ responses were analysed for lexical translation errors that were caused by phonological parameter substitutions. Unlike previous related studies, tracking phonological substitution errors during sentence translation allows for the characterization of uncontrolled and naturalistic perception errors. Results indicated that learners made mostly movement errors followed by handshape and location errors. Learners made more movement errors for sentences signed by the M2L2 learner relative to those by the native signer. Additionally, high proficiency learners made more handshape errors than low proficiency learners. Taken together, this pattern of results suggests that late M2L2 learners are poor at perceiving the movement parameter and M2L2 production variability of the movement parameter negatively contributes to perception.

The Beneficial Role of L1 Spoken Language Skills on Initial L2 Sign Language Learning: Cognitive and Linguistic Predictors of M2L2 Acquisition.

Understanding how language modality (i.e., signed vs. spoken) affects second language outcomes in hearing adults is important both theoretically and pedagogically, as it can determine the specificity of second language (L2) theory and inform how best to teach a language that uses a new modality. The present study investigated which cognitive-linguistic skills predict successful L2 sign language acquisition. A group ( n = 25) of adult hearing L2 learners of American Sign Language underwent a cognitive-linguistic test battery before and after one semester of sign language instruction. A number of cognitive-linguistic measures of verbal memory, phonetic categorization skills, and vocabulary knowledge were examined to determine whether they predicted proficiency in a multiple linear regression analysis. Results indicated that English vocabulary knowledge and phonetic categorization skills predicted both vocabulary growth and self-rated proficiency at the end of one semester of instruction. Memory skills did not significantly predict either proficiency measures. These results highlight how linguistic skills in the first language (L1) directly predict L2 learning outcomes regardless of differences in L1 and L2 language modalities.

Operationalization of Sign Language Phonological Similarity and Its Effects on Lexical Access.

Cognitive mechanisms for sign language lexical access are fairly unknown. This study investigated whether phonological similarity facilitates lexical retrieval in sign languages using measures from a new lexical database for American Sign Language. Additionally, it aimed to determine which similarity metric best fits the present data in order to inform theories of how phonological similarity is constructed within the lexicon and to aid in the operationalization of phonological similarity in sign language. Sign repetition latencies and accuracy were obtained when native signers were asked to reproduce a sign displayed on a computer screen. Results indicated that, as predicted, phonological similarity facilitated repetition latencies and accuracy as long as there were no strict constraints on the type of sublexical features that overlapped. The data converged to suggest that one similarity measure, MaxD, defined as the overlap of any 4 sublexical features, likely best represents mechanisms of phonological similarity in the mental lexicon. Together, these data suggest that lexical access in sign language is facilitated by phonologically similar lexical representations in memory and the optimal operationalization is defined as liberal constraints on overlap of 4 out of 5 sublexical features-similar to the majority of extant definitions in the literature.