Low-Frequency Entrainment to Visual Motion Underlies Sign Language Comprehension.

When people listen to speech, neural activity tracks the entropy fluctuation in the acoustic envelope of the signal. This signal-based entrainment has been shown to be the basis of speech parsing and comprehension. In this electroencephalography (EEG) study, we compute sign language users' cortical tracking of changes in visual dynamics of the communicative signal in the time-direct videos of sign language, and their time-reversed counterparts, and assess the relative contribution of response frequencies between.2 and 12.4 Hz to comprehension using a machine learning approach to brain state classification. Lower frequencies of EEG response (.2-4 Hz) yield 100% classification accuracy, while information about cortical tracking of the visual envelope in higher frequencies is less informative. This suggests that signers rely on lower visual frequency data, such as envelope of visual signal, for sign language comprehension. In the context of real-time language processing, given the speed of comprehension responses, this suggests that fluent signers employ a predictive processing heuristic based on sign language knowledge.

The Use of ASL to Support the Development of English and Literacy.

The purpose of this article is to review research dealing with the use of ASL in teaching English and literacy. I review some of the literature (and direct readers to additional sources) that indicates that early learning of ASL need not create concerns for future development of English structure, speech, or other cognitive skills. I also suggest ways in which ASL can contribute directly to developing more of the highlevel skills needed for fluent reading and writing. The global benefit of learning ASL as a first language is that it creates a standard bilingual situation in which teachers and learners can take advantage of one language to assist in acquiring the other and in the transfer of general knowledge. As part of this discussion, I compare English and ASL as natural languages for similarities and differences.

Stress in ASL: empirical evidence and linguistic issues.

The study of signed languages provides an opportunity to identify those characteristics of language that are universal and to investigate the effect of production modality (signed vs. spoken) on the grammar. Over time, American Sign Language (ASL) has accommodated itself to the production and perception requirements of the manual/visual modality, resulting in a prosodic system that is comparable in function to spoken languages but different in means of expression. The present focus is on phrasal prominence in ASL. I review the marking of stress and phrase boundaries in ASL, and discuss prominence assignment at the phrasal level, with brief mention of lexical stress. At the kinematic level, there is a modality effect in marking of linguistic prominence but no modality effect with respect to marking phrase position. Of significance is the fact that ASL lacks phrasal prominence plasticity, that is the ability to move prominence to mark focus in a sentence location other than phrase final. I review the typological implications of how ASL handles prominence as compared to other languages.

Modality interactions of speech and signing in simultaneous communication.

This study addresses speech and signing interaction during simultaneous communication (SC). Productions of sentence stimuli by ASL-English bilinguals (CODAs) and signed English (SE) users who know no ASL (SIMCOMs) were compared in two conditions (speech-alone or signing-alone, speech and signing combined). Speech took longer combined than alone, whereas SE took longer alone than combined. The increased duration of speech-combined resulted from increased syllable duration, number of gaps, and gap duration. Rate of signing had a significant effect on speech duration. The decreased duration of signed sentences combined resulted from decreased sign duration, decreased gap duration, and increased sign omissions. Knowledge of ASL was reflected in qualitative differences between the two groups. Sign omissions were analyzed by grammatical category; these are discussed in terms of context-supported permissible deletions and the compensatory use of ASL nonmanual marking devices.

Backwards signing and ASL syllable structure.

A recurrent question raised by the study of signed languages concerns the linguistic effect of the modality in which the language is produced. Is the modality difference between speech and sign reflected merely in the nature of the phonetic features that map into production and perception, or is it the case that there might be higher level organizational differences between the two linguistic modalities? The present study addresses the nature of the modality effect inside the syllable, namely whether syllables in ASL display evidence of segmental composition. Data from backwards signing are presented to demonstrate that the phonological representations that must be available to signers when they perform backwards signing tasks cannot be adequately represented with the current models that posit segmental composition of ASL syllables. Instead, it is argued that it is sufficient to make reference to distinctive features, in syllable initial and syllable final positions, and that there is no support for any further internal segmental divisions.

Perceptual evidence against internal structure in American Sign Language syllables.

Syllables in spoken languages have been argued to have an internal structure which may cluster the consonants and vowels into subgroups. The most commonly used subgroups are the Onset (initial consonants) and Rhyme (vowel and remaining consonants), with the further possibility of dividing the Rhyme into Nucleus (the vowel and any on- or off-glides) and the Coda (the final consonants). Although linguistic debate continues about the exact formulation of such syllable models, the evidence is clear that listeners identify rhythmic beats at a particular point inside the syllable, namely at the release of the initial consonants into the following linguistically stressed vowels (referred to as the syllable peak, assumed to be part of the Nucleus). To determine whether such loci would be identified for syllables in American Sign Language, deaf native signers, hearing native signers, and hearing subjects unfamiliar with sign language were asked to tap to videotaped signed stimuli. Analysis of the tap locations in signed syllables revealed a relatively flat distribution across the syllable for all three groups and for individual subjects. The absence of syllable peak perception is discussed in relation to the motoric characteristics of sign production.

Acute necrotizing ulcerative gingivitis in children with cancer.

We reviewed the findings for 15 immunosuppressed children with cancer who had 18 episodes of acute necrotizing ulcerative gingivitis. Predisposing factors were then assessed for their influence on the course of infection. The nutritional status and oral hygiene of most patients were poor. Eleven of the 18 episodes involved the spontaneous exfoliation of primary or permanent teeth, and 16 of the 18 episodes were complicated by other infections. The infection completely cleared in only two of ten patients who were not in remission and persisted for more than 15 weeks or until death in all of the remaining patients with active disease. By contrast, all six episodes of infection during remission cleared within an average of 4 1/2 weeks. Among the many contributing factors, decreased host resistance, relapse, and neutropenia seemed to have the most negative influence on recovery from this severe form of gingivitis.

Complement structures in the language of deaf students.

Four hundred and twenty-seven deaf students (age 10 to 19 years) and 60 hearing children (age eight to 10 years) judged the grammaticality of sample sentences which contained infinitival or gerundive complements. Results indicated improvement with increasing age for deaf students. Even the youngest hearing students consistently obtained higher scores than most of the deaf students. Although the function of the complement (as subject or object) did not make a difference in performance, the type of complement did. POSS-ing complements were easier than for-to complements. Verb type also influenced performance.

Some aspects of the verb system in the language of deaf students.

Approximately 480 deaf students (age 10 to 19 years) and 60 hearing students (age eight to 10 years) were asked to judge the grammaticality of sentences containing auxiliary verbs, of sentences where the verb had been deleted, and of sentences in which the verb tense was not marked. The results indicated that deaf students have considerable difficulty with the verb system of English. This difficulty was most pronounced in the formation of tense and voice and in agreement in number and tense. A possible ordering for the acquisition of tense did emerge; from earliest to latest it is: simple past, future, present progressive, perfective, and passive. Improvement in grammaticality judgments appeared to come from an increase in recognition that incorrect sentences were ungrammatical.

Pronominalization in the language of deaf students.

Four hundred and eighty deaf students (age 10 to 18 years) and 60 hearing children (age eight to 10 years) were required to complete a stimulus sentence by selecting the appropriate pronoun from a list provided. The results indicated that subject and object case pronouns were easier than possessive adjectives, which were in turn easier than possessive pronouns and reflexives. Correct use of relative pronouns was the most difficult for both deaf and hearing subjects. Generalizations about the acquisition of the pronoun system must be limited, as it appeared that pronouns are mastered on a pronoun-by-pronoun basis rather than by categories (person, number, case) for both the deaf and hearing subjects.