Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Sign Language”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 163 records · Page 9Linked to original sources
PubMed1981

Perception of American sign language in dynamic point-light displays.

Perception of dynamic events of American Sign Language (ASL) was studied by isolating information about motion in the language from information about form. Four experiments utilized Johansson's technique for presenting biological motion as moving points of light. In the first, deaf signers were highly accurate in matching movements of lexical signs presented in point-light displays to those normally presented. Both discrimination accuracy and the pattern of errors were similar in this matching task to that obtained in a control condition in which the same signs were always represented normally. The second experiment showed that these results held for discrimination of morphological operations presented in point-light displays as well. In the third experiment, signers were able to accurately identify signs of a constant handshape and morphological operations acting on signs presented in point-light displays. Finally, in Experiment 4, we evaluated what aspects of the motion patterns carried most of the information for sign identifiability. We presented signs in point-light displays with certain lights removed and found that the movement of the fingertips, but not of any other pair of points, is necessary for sign identification and that, in general, the more distal the joint, the more information its movement carries.

Adult↗
PubMed2004

W(h)ither the deaf community? Population, genetics, and the future of Australian sign language.

According to enrollments in schools for the deaf and data from the national census and neonatal hearing screening programs, the incidence of severe and profound childhood deafness in Australia is, and has been, less than commonly assumed. Factors implicated include improved medical care, mainstreaming, cochlear implants, and genetic science. Data for the United States, Britain, and other developed countries seem consistent with those for Australia. Declining prevalence and incidence rates have immediate implications for sign-based education, teacher-of-the-deaf training programs, and educational interpreting. There are also serious consequences for research, documentation, and teaching regarding Australian Sign Language (Auslan), and for the future viability of Auslan. Prompt action is essential if a credible corpus of Auslan is to be collected as the basis for a valid and verifiable description of one of the few native sign languages in the world with significant attested historical depth.

Australia↗
PubMed2001

Accessibility of spoken, written, and sign language in Landau-Kleffner syndrome: a linguistic and functional MRI study.

Landau-Kleffner syndrome (LKS) is an acquired aphasia which begins in childhood and is thought to arise from an epileptic disorder within the auditory speech cortex. Although the epilepsy usually subsides at puberty, a severe communication impairment often persists. Here we report on a detailed study of a 26-year old, left-handed male, with onset of LKS at age 5 years, who is aphasic for English but who learned British Sign Language (BSL) at age 13. We have investigated his skills in different language modalities, recorded EEGs during wakefulness, sleep, and under conditions of auditory stimulation, measured brain stem auditory-evoked potentials (BAEP), and performed functional MRI (fMRI) during a range of linguistic tasks. Our investigation demonstrated severe restrictions in comprehension and production of spoken English as well as lip-reading, while reading was comparatively less impaired. BSL was by far the most efficient mode of communication. All EEG recordings were normal, while BAEP showed minor abnormalities. fMRI revealed: 1) powerful and extensive bilateral (R > L) activation of auditory cortices in response to heard speech, much stronger than when listening to music; 2) very little response to silent lip-reading; 3) strong activation in the temporo-parieto-occipital association cortex, exclusively in the right hemisphere (RH), when viewing BSL signs. Analysis of these findings provides novel insights into the disturbance of the auditory speech cortex which underlies LKS and its diagnostic evaluation by fMRI, and underpins a strategy of restoring communication abilities in LKS through a natural sign language of the deaf (with Video)

Adult↗
PubMed1994

Cultural transmission of a sign language when deafness is caused by recessive alleles at two independent loci.

Two unlinked autosomal loci are assumed to affect the ability to hear in such a way that homozygosity for the recessive allele at either locus causes deafness. The five deaf genotypes are subject to the same negative selection due to a lower likelihood of marriage, but unmarried deaf persons remain socially active and participate in the cultural transmission of sign languages. Marriages are assortative for deafness or for hearing, and mutation occurs irreversibly from the dominant to recessive allele at each locus at the same rate. At mutation-selection balance, the fully polymorphic equilibrium is symmetrical. Based on this genetic model, we consider the relative importance of various forms of cultural transmission as they affect the persistence of sign languages. Horizontal transmission is shown to be effective when deaf children are able to interact with many peers. This observation is especially pertinent if assortative meeting of deaf children occurs, for example, at schools for the deaf. Oblique transmission can also be effective, but the literature suggests that this kind of transmission plays only a minor role. It is necessary, however, that some form of cultural transmission occur between generations. Thus, vertical transmission is a critical factor, despite the fact that parent-child transmission is often interrupted due to the recessive inheritance of deafness. In particular, the contribution of vertical transmission is enhanced by assortative mating for deafness.

Child Development↗
PubMed1978

Acquisition of sign language by autistic children. I: Expressive labelling.

There has been growing interest in teaching sign language to autistic children who have failed to develop speech. However, controlled experimentation in this area is nonexistent. In the present study, four nonverbal autistic children were taught expressive sign labels for common objects, using a training procedure that consisted of prompting, fading, and stimulus rotation. The efficacy of the procedure was demonstrated in a multiple-baseline design across objects. The results were reliable, replicable across children, and generalizable across therapists. A stimulus control analysis demonstrated that, for three of the children, correct signing was controlled solely by the visual cues associated with the presentation of a given object and was independent of respect to the known perceptual and linguistic deficits of autistic children.

Adolescent↗
PubMed1993

[Paired-associate learning in deaf patients with and without sign language assist].

In previous experiments our group has shown that test subjects with normal hearing are able to draw pertinent information from visual signals generated from the analysis and transformation of speech. However, the results of these tests could be applied indiscriminately to the deaf. More recently we have studied the speed with which deaf subjects could learn to identify visual patterns generated from speech, the stability of learning, and the strategies developed by our subjects for learning sonogram-like patterns. The subjects tested were taught under two different conditions: pedagogy based on sign language and pedagogy based on speech. Deaf subjects and subjects with normal hearing dealt with associating visual patterns with meanings in a similar fashion. Deaf subjects required more repetitions to associate patterns with meanings than those with normal hearing, but they needed less time. The deaf developed strategies that increased their ability to learn new lists of patterns. In general, the deaf learned lists of patterns in the framework of feedback training well. Interestingly, the deaf taught on the basis of sign language did better than those taught on the basis of speech.

Adolescent↗
PubMed1976

Sign language acquisition in a mute autistic boy.

A mute autistic boy learned to communicate extensively through American Sign Language. Over a six-month period he produced many spontaneous signs and sign combinations, and analyses of child's sign combinations indicated the presence of a full range of semantic relations. Further evidence of conceptual progress was provided by the child's increased score on the Peabody Picture Vocabulary Test. In addition, parents' and teacher's reports indicated that the child's social behavior improved. The extent of the boy's linguistic progress and associated improvement in social behavior markedly exceeds that usually reported for mute autistic children.

Autistic Disorder↗
PubMed1987

Limits of visual communication: the effect of signal-to-noise ratio on the intelligibility of American Sign Language.

To determine the limits of human observers' ability to identify visually presented American Sign Language (ASL), the contrast s and the amount of additive noise n in dynamic ASL images were varied independently. Contrast was tested over a 4:1 range; the rms signal-to-noise ratios (s/n) investigated were s/n = 1/4, 1/2, 1, and infinity (which is used to designate the original, uncontaminated images). Fourteen deaf subjects were tested with an intelligibility test composed of 85 isolated ASL signs, each 2-3 sec in length. For these ASL signs (64 x 96 pixels, 30 frames/sec), subjects' performance asymptotes between s/n = 0.5 and 1.0; further increases in s/n do not improve intelligibility. Intelligibility was found to depend only on s/n and not on contrast. A formulation in terms of logistic functions was proposed to derive intelligibility of ASL signs from s/n, sign familiarity, and sign difficulty. Familiarity (ignorance) is represented by additive signal-correlated noise; it represents the likelihood of a subject's knowing a particular ASL sign, and it adds to s/n. Difficulty is represented by a multiplicative difficulty coefficient; it represents the perceptual vulnerability of an ASL sign to noise and it adds to log(s/n).

Adult↗
PubMed1979

Teaching autistic children to use sign language: some research issues.

Three questions are raised with respect to the use of sign language as an alternative system of communication for nonverbal autistic children. First, does teaching a child to sign facilitate speech development? The data suggest that following simultaneous communication training, mute children are not likely to learn to talk; however, a combination of simultaneous communication training and separate vocal training may have a synergetic effect on speech development. In contrast, children who initially have good verbal imitation skills apparently show gains in speech following simultaneous communication training alone. Second, what is the upper limit of sign acquisition? Data suggest that abstract concepts, syntax, and generative skills can be taught. Procedures used in the operant conditioning of speech may prove useful in training complex signing skills. Third, does sign acquisition result in a general improvement in adaptive functioning? It appears that following sign training, some children do show increases in spontaneous communication, decreases in self-stimulatory behavior, and improvement in social skills. However, these outcomes are often difficult to interpret. Some data are described that help clarify the relationship between sign training and general behavioral improvement.

Adaptation, Psychological↗
PubMed2004

Neural systems for sign language production: mechanisms supporting lexical selection, phonological encoding, and articulation.

Overt production of ASL signs was evaluated using H(2)(15)O PET to differentiate brain systems that support sign language production at the lexical-selection and phonological-articulatory levels. Subjects were 16 right-handed, congenitally deaf native ASL signers (10 women, six men; age 20 to 29 years). Scans were performed while subjects (1) passively viewed ASL nouns, (2) repeated nouns, (3) generated verbs in response to these nouns, (4) passively viewed videotaped segments depicting transitive actions, and (5) generated a verb to describe these actions. Conjunctions between the two verb-generation tasks revealed left-lateralized activation of perisylvian, frontal, and subcortical regions commonly observed in spoken language generation tasks and implicated in processes of semantic feature binding and lexical selection. Analysis of noun repetition minus viewing condition revealed activation of distinct systems supporting phonological encoding and articulation, including bilateral activation of sensorimotor areas and association cortices in the temporal, parietal, and occipital lobes. In addition, lexical-selection and articulatory processes were associated with activation of different corticostriatal-thalamocortical circuits: articulation with activation of the motor, and lexical-selection with activation of the prefrontal circuits, respectively. The results collectively provide insight into dissociable neural systems underlying these psycholinguistic functions. In addition, activation of regions that are typically associated with the auditory system during sign production suggests that these regions may support modality-independent linguistic processes, or may indicate cross-modal plasticity within the deaf brain.

Adult↗
PubMed1996

Motivational and attitudinal orientations in learning American Sign Language.

Integrative motivation was found to correlate significantly with sign language proficiency of adult learners at a post-secondary program for deaf students. Instrumental motives, however, were perceived as less important. Higher achievement in ASL was also associated with a positive cultural attitude toward deaf people. Learning of ASL as a second language may be enhanced if instructors design strategies that build upon these cultural and integrative motives and provide rewarding experiences to adult learners.

Journal Article↗
PubMed1991

Repetition priming with aspect and agreement morphology in American Sign Language.

Two experiments are reported which investigate the organization and recognition of morphologically complex forms in American Sign Language (ASL) using a repetition priming technique. Three major questions were addressed: (1) Is morphological priming a modality-independent process? (2) Do the different properties of agreement and aspect morphology in ASL affect priming strength? (3) Does early language experience influence the pattern of morphological priming? Prime-target pairs (separated by 26-32 items) were presented to deaf subjects for lexical decision. Primes were inflected for either agreement (dual, reciprocal, multiple) or aspect (habitual, continual); targets were always the base form of the verb. Results of Experiment 1 indicated that subjects exposed to ASL in late childhood were not as sensitive to morphological complexity as native signers, but this result was not replicated in Experiment 2. Both experiments showed stronger facilitation with aspect morphology compared to agreement morphology. Repetition priming was not observed for nonsigns. The scope and structure of the morphological rules for ASL aspect and agreement are argued to explain the different patterns of morphological priming.

Adult↗
PubMed2004

Conceptual locations and pronominal reference in American Sign Language.

We report the results of an experiment investigating the ramifications of using space to express coreference in American Sign Language (ASL). Nominals in ASL can be associated with locations in signing space, and pronouns are directed toward those locations to convey coreference. A probe recognition technique was used to investigate the case of "locus doubling" in which a single referent is associated with two distinct spatial locations. The experiment explored whether an ASL pronoun activates both its antecedent referent and the location associated with that referent. An introductory discourse associated a referent (e.g, MOTHER) with two distinct locations (eg., STOREleft, KITCHENright), and a continuation sentence followed that either contained a pronoun referring to the referent in one location or contained no anaphora (the control sentence). Twenty-four deaf participants made lexical decisions to probe signs presented during the continuation sentences. The probe signs were either the referent of the pronoun, the referent-location determined by the pronoun, or the most recently mentioned location (not referenced by the pronoun). The results indicated that response times to referent nouns were faster in the pronoun than in the no-pronoun control condition and that response times to the location signs did not differ across conditions. Thus, the spatial nature of coreference in ASL does not alter the processing mechanism underlying the on-line interpretation of pronouns. Pronouns activate only referent nouns, not spatial location nouns associated with the referent.

Adult↗
PubMed2004

Text generation from Taiwanese Sign Language using a PST-based language model for augmentative communication.

This paper proposes a novel approach to the generation of Chinese sentences from ill-formed Taiwanese Sign Language (TSL) for people with hearing impairments. First, a sign icon-based virtual keyboard is constructed to provide a visualized interface to retrieve sign icons from a sign database. A proposed language model (LM), based on a predictive sentence template (PST) tree, integrates a statistical variable n-gram LM and linguistic constraints to deal with the translation problem from ill-formed sign sequences to grammatical written sentences. The PST tree trained by a corpus collected from the deaf schools was used to model the correspondence between signed and written Chinese. In addition, a set of phrase formation rules, based on trigger pair category, was derived for sentence pattern expansion. These approaches improved the efficiency of text generation and the accuracy of word prediction and, therefore, improved the input rate. For the assessment of practical communication aids, a reading-comprehension training program with ten profoundly deaf students was undertaken in a deaf school in Tainan, Taiwan. Evaluation results show that the literacy aptitude test and subjective satisfactory level are significantly improved.

Adolescent↗
PubMed1981

Nonauditory suffix effects in congenitally deaf signers of American Sign Language.

A series of unordered recall tasks was administered to groups of congenitally deaf subjects for whom American Sign Language (ASL) is the principal means of communication. A suffix effect was observed when an ASL sign was suffixed to a list of ASL signs (Experiment 1), and when a line drawing of an ASL sign was suffixed to a list of line drawings of ASL signs (Experiment 3). The suffix effect was a diminished magnitude when a printed English word was suffixed to a list of printed words (Experiment 2). The findings of Experiment 1 and 3 argue conclusively against the suffix effect resulting solely from sensory store differences. Additionally, the results of Experiment 3 argue conclusively against explanation of the effect as arising solely from differences in the processing of "static" versus "changing-state" input.

Deafness↗
PubMed2002

Neural systems underlying British Sign Language and audio-visual English processing in native users.

In order to understand the evolution of human language, it is necessary to explore the neural systems that support language processing in its many forms. In particular, it is informative to separate those mechanisms that may have evolved for sensory processing (hearing) from those that have evolved to represent events and actions symbolically (language). To what extent are the brain systems that support language processing shaped by auditory experience and to what extent by exposure to language, which may not necessarily be acoustically structured? In this first neuroimaging study of the perception of British Sign Language (BSL), we explored these questions by measuring brain activation using functional MRI in nine hearing and nine congenitally deaf native users of BSL while they performed a BSL sentence-acceptability task. Eight hearing, non-signing subjects performed an analogous task that involved audio-visual English sentences. The data support the argument that there are both modality-independent and modality-dependent language localization patterns in native users. In relation to modality-independent patterns, regions activated by both BSL in deaf signers and by spoken English in hearing non-signers included inferior prefrontal regions bilaterally (including Broca's area) and superior temporal regions bilaterally (including Wernicke's area). Lateralization patterns were similar for the two languages. There was no evidence of enhanced right-hemisphere recruitment for BSL processing in comparison with audio-visual English. In relation to modality-specific patterns, audio-visual speech in hearing subjects generated greater activation in the primary and secondary auditory cortices than BSL in deaf signers, whereas BSL generated enhanced activation in the posterior occipito-temporal regions (V5), reflecting the greater movement component of BSL. The influence of hearing status on the recruitment of sign language processing systems was explored by comparing deaf and hearing adults who had BSL as their first language (native signers). Deaf native signers demonstrated greater activation in the left superior temporal gyrus in response to BSL than hearing native signers. This important finding suggests that left- temporal auditory regions may be privileged for processing heard speech even in hearing native signers. However, in the absence of auditory input this region can be recruited for visual processing.

Adolescent↗
PubMed2001

Electrocorticographic gamma activity during word production in spoken and sign language.

OBJECTIVE: To investigate the functional-neuroanatomic substrates of word production using signed versus spoken language. METHODS: The authors studied single-word processing with varying input and output modalities in a 38-year-old woman with normal hearing and speech who had become proficient in sign language 8 years before developing intractable epilepsy. Subdural electrocorticography (ECoG) was performed during picture naming and word reading (visual inputs) and word repetition (auditory inputs); these tasks were repeated with speech and with sign language responses. Cortical activation was indexed by event-related power augmentation in the 80- to 100-Hz gamma band, and was compared with general principles of functional anatomy and with subject-specific maps of the same or similar tasks using electrical cortical stimulation (ECS). RESULTS: Speech outputs activated tongue regions of the sensorimotor cortex, and sign outputs activated hand regions. In addition, signed word production activated parietal regions that were not activated by spoken word production. Posterior superior temporal gyrus was activated earliest and to the greatest extent during auditory word repetition, and the basal temporal-occipital cortex was activated similarly during naming and reading, reflecting the different modalities of input processing. With few exceptions, topographic patterns of ECoG gamma were consistent with ECS maps of the same or similar language tasks. CONCLUSIONS: Spoken and signed word production activated many of the same cortical regions, particularly those processing auditory and visual inputs; however, they activated different regions of sensorimotor cortex, and signing activated parietal cortex more than did speech. This study illustrates the utility of electrocorticographic gamma for studying the neuroanatomy and processing dynamics of human language.

Brain Mapping↗