Enhanced facial discrimination: effects of experience with American sign language

On-line comprehension of American Sign Language (ASL) requires rapid discrimination of linguistic facial expressions. We hypothesized that ASL signers' experience discriminating linguistic facial expressions might lead to enhanced performance for discriminating among different faces. Five experiments are reported that investigate signers' and non-signers' ability to discriminate human faces photographed under different conditions of orientation and lighting (the Benton Test of Facial Recognition). The results showed that deaf signers performed significantly better than hearing non-signers. Hearing native signers (born to deaf parents) also performed better than hearing nonsigners, suggesting that the enhanced performance of deaf signers is linked to experience with ASL rather than to auditory deprivation. Deaf signers who acquired ASL in early adulthood did not differ from native signers, which suggests that there is no 'critical period' during which signers must be exposed to ASL in order to exhibit enhanced face discrimination abilities. When the faces were inverted, signing and nonsigning groups did not differ in performance. This pattern of results suggests that experience with sign language affects mechanisms specific to face processing and does not produce a general enhancement of visual discrimination. Finally, a similar pattern of results was found with signing and nonsigning children, 6-9 years old. Overall, the results suggest that the brain mechanisms responsible for face processing are somewhat plastic and can be affected by experience. We discuss implications of these results for the relation between language and cognition.     

Modality of language shapes working memory: evidence from digit span and spatial span in ASL signers

Deaf children who are native users of American Sign Language (ASL) and hearing children who are native English speakers performed three working memory tasks. Results indicate that language modality shapes the architecture of working memory. Digit span with forward and backward report, performed by each group in their native language, suggests that the language rehearsal mechanisms for spoken language and for sign language differ in their processing constraints. Unlike hearing children, deaf children who are native signers of ASL were as good at backward recall of digits as at forward recall, suggesting that serial order information for ASL is stored in a form that does not have a preferred directionality. Data from a group of deaf children who were not native signers of ASL rule out explanations in terms of a floor effect or a nonlinguistic visual strategy. Further, deaf children who were native signers outperformed hearing children on a nonlinguistic spatial memory task, suggesting that language expertise in a particular modality exerts an influence on nonlinguistic working memory within that modality. Thus, language modality has consequences for the structure of working memory, both within and outside the linguistic domain.     

Differences in the use of American Sign Language morphology by deaf children: implications for parents and teachers

Newport (1988) has noted differences in how American Sign Language (ASL) is used by the following three groups of deaf adults: those with deaf parents (native signers); those, with hearing parents, who learned ASL upon entering school at age 5 years (early signers); and those who learned to sign after puberty (late signers). The present study extends this research to children by investigating the use of morphological inflections in ASL by native and early signers. Thirty deaf children between ages 3 and 9 years were asked to sign a story in ASL. The videotaped stories were analyzed for morphological and contextual complexity. Qualitative differences were found between native and early signers on measures relating to the aspectual complexity of signs but not on measures relating to the complexity of the utterance. Implications of these differences are discussed in terms of communication at home and ASL use in the classroom.     

A study of the relationship between American sign language and English literacy

This article presents the findings of a study of the relationship between American Sign Language (ASL) skills and English literacy among 160 deaf children. Using a specially designed test of ASL to determine three levels of ASL ability, we found that deaf children who attained the higher two levels significantly outperformed children in the lowest ASL ability level in English literacy, regardless of age and IQ. Furthermore, although deaf children with deaf mothers outperformed deaf children of hearing mothers in both ASL and English literacy, when ASL level was held constant, there was no difference between these two groups, except in the lowest level of ASL ability. The implication of this research is straightforward and powerful: Deaf children's learning of English appears to benefit from the acquisition of even a moderate fluency in ASL.     

How Do Profoundly Deaf Children Learn to Read?

Reading requires two related, but separable, capabilities: (1) familiarity with a language, and (2) understanding the mapping between that language and the printed word (Chamberlain & Mayberry, 2000; Hoover & Gough, 1990). Children who are profoundly deaf are disadvantaged on both counts. Not surprisingly, then, reading is difficult for profoundly deaf children. But some deaf children do manage to read fluently. How? Are they simply the smartest of the crop, or do they have some strategy, or circumstance, that facilitates linking the written code with language? A priori one might guess that knowing American Sign Language (ASL) would interfere with learning to read English simply because ASL does not map in any systematic way onto English. However, recent research has suggested that individuals with good signing skills are not worse, and may even be better, readers than individuals with poor signing skills (Chamberlain & Mayberry, 2000). Thus, knowing a language (even if it is not the language captured in print) appears to facilitate learning to read. Nonetheless, skill in signing does not guarantee skill in reading—reading must be taught. The next frontier for reading research in deaf education is to understand how deaf readers map their knowledge of sign language onto print, and how instruction can best be used to turn signers into readers.     

Signposts to development: theory of mind in deaf children

Possession of a "theory of mind" (ToM)--as demonstrated by an understanding of the false beliefs of others--is fundamental in children's cognitive development. A key question for debate concerns the effect of language input on ToM. In this respect, comparisons of deaf native-signing children who are raised by deaf signing parents with deaf late-signing children who are raised by hearing parents provide a critical test. This article reports on two studies (N = 100 and N = 39) using "thought picture" measures of ToM that minimize verbal task-performance requirements. These studies demonstrated that even when factors such as syntax ability, mental age in spatial ability, and executive functioning were considered, deaf late signers still showed deficits in ToM understanding relative to deaf native signers or hearing controls. Even though the native signers were significantly younger than a sample of late signers matched for spatial mental age and scores on a test of receptive sign language ability, native signers outperformed late signers on pictorial ToM tasks. The results are discussed in terms of access to conversation and extralinguistic influences on development such as the presence of sibling relationships, and suggest that the expression of a ToM is the end result of social understanding mediated by early conversational experience.     

Comparing action gestures and classifier verbs of motion: evidence from Australian Sign Language, Taiwan Sign Language, and nonsigners' gestures without speech

Recent research into signed languages indicates that signs may share some properties with gesture, especially in the use of space in classifier constructions. A prediction of this proposal is that there will be similarities in the representation of motion events by sign-naive gesturers and by native signers of unrelated signed languages. This prediction is tested for deaf native signers of Australian Sign Language (Auslan), deaf signers of Taiwan Sign Language (TSL), and hearing nonsigners using the Verbs of Motion Production task from the Test Battery for American Sign Language (ASL) Morphology and Syntax. Results indicate that differences between the responses of nonsigners, Auslan signers, and TSL signers and the expected ASL responses are greatest with handshape units; movement and location units appear to be very similar. Although not definitive, these data are consistent with the claim that classifier constructions are blends of linguistic and gestural elements.     

Intermodal Perception of Adult and Child Faces and Voices by Infants

This research investigated the ability of 4- and 7-month-old infants to match unfamiliar, dynamic faces and voices on the basis of age or maturity. In Experiment 1, infants received videotaped trials of an adult and a child of the same gender, side by side, speaking a nursery rhyme in synchrony with one another. The voice to one and then the other face was played in synchrony with the movements of both faces in a random order across 12 trials. On one block of 6 trials a man and a boy were presented, and on the other block a woman and a girl. Results indicated significant matching of the faces and voices at both ages, and the infant's prior experience with children appeared to facilitate matching at 7 months. Further, a visual preference for the children's faces was found. Experiment 2 assessed matching to the same events by 7-month-olds, only with the faces inverted. Results indicated no evidence of matching; however, the visual preference for the children's faces was replicated. Together, the findings suggest that infants are able to detect invariant intermodal relations specifying the age or maturity of a person's face and voice. This matching was most likely based on information that was degraded by inverting the faces, including invariant relations between the sound of the voice and configurational aspects of the face, or between temporal aspects of the voice and the relative motion of facial features.     

Written language abilities in deaf Italians

Written texts produced by 10 Italian deaf native signers in four different writing tasks were analyzed. Data analysis focused on linguistic and orthographic nonstandard forms. The written production of deaf subjects with deaf parents (DD) was compared to the written production in two control groups: a group of 10 hearing subjects with deaf parents (HD) and a group of 10 subjects who have had no contact with deaf people or sign language (HH). The results duplicate findings from previous studies. Deaf subjects display a pattern of selective difficulty with Italian grammatical morphology, especially with free-standing function words. The four different writing tasks used in the present study yield results indicating that text type does influence our assessment of deaf writing abilities. A comparison of the texts written by deaf native signers with those of two hearing groups confirms the view that difficulties in the acquisition of written Italian are best explained by deafness itself, not by the influence of a previously acquired Sign Language, and that the specific difficulties with grammatical morphology displayed by our deaf subjects cannot be attributed solely to their limited experience with written Italian.     

Studies of neural processing in deaf signers: toward a neurocognitive model of language processing in the deaf

The ability to comprehend and produce language stands as a defining characteristic of human cognition and enables the transfer of knowledge and culture within human society. A proper characterization of the human capacity for language is required for the development of interventions that may be used to assist those individuals who have failed to achieve, or who have lost competence in, language behaviors. For signed languages, models of competent language use are lacking. This lack of knowledge hampers the development of effective assessment measures for deaf children who may be experiencing learning problems beyond those confronting the normal deaf child. I discuss two research avenues that have begun to provide a window into the neural systems involved in sign language processing: studies of language disruptions in adult deaf signers who have suffered brain injury, and studies of functional brain imaging in normal deaf signers. This research provides a basis for the development of a comprehensive neurocognitive model of sign language processing.     

Using online glossing lessons for accelerated instruction in ASL for preservice deaf education majors

Teachers of deaf and hard of hearing students must serve as language models for their students. However, preservice deaf education teachers typically have at most only four semesters of American Sign Language (ASL) training. How can their limited ASL instructional time be used to increase their proficiency? Studies involving deaf and hard of hearing students have revealed that glosses (written equivalents of ASL sentences) can serve as "bridges" between ASL and English. The study investigated whether glossing instruction can facilitate hearing students' learning of ASL. A Web site was developed in which ASL glossing rules were explained and glossing exercises provided. Posttest scores showed the experimental group improving from 39% to 71% on ASL grammar knowledge. These findings indicate that online glossing lessons may provide the means to obtain ASL skills more readily, thus preparing deaf education teachers to serve as ASL language models.     

Visual constructive and visual-motor skills in deaf native signers

Visual constructive and visual-motor skills in the deaf population were investigated by comparing performance of deaf native signers (n=20) to that of hearing nonsigners (n=20) on the Beery-Buktenica Developmental Test of Visual-Motor Integration, Rey-Osterrieth Complex Figure Test, Wechsler Memory Scale Visual Reproduction subtest, and Stanford-Binet Intelligence Scale Paper Folding and Cutting subtest. Deaf signers were found to perform similarly to hearing controls, suggesting that these tests are valid assessment instruments to use with deaf individuals.     

The relation between phonological memory skills and reading ability in greek-speaking children: Can training of phonological memory contribute to reading development?

This study was designed to examine whether there is a relationship between phonological memory and reading ability in Greek-speaking children aged between 6 and 9 years. An additional aim of the study was to investigate whether training of phonological memory during preschool years enhances reading achievement during early school years. In Experiment I, the phonological memory ability of 136 first graders, 134 second graders and 132 from each of the third and fourth grades was assessed with a nonword repetition test. A reading test was also used to evaluate the reading skills of the above subjects. The results revealed strong links between reading performance and nonword repetition scores. 120 kindergarten children randomly assigned to a control and an experimental group participated in Experiment 2. Training that involved practice in the repetition of nonwords was used as a means of promoting the phonological memory of the children in the experimental group over the course of one year in school. Subjects’ reading ability was tested during the last month of their first year in the primary school. The findings showed that the performance of the trained subjects in the reading test was superior to that of the control subjects. Such evidence underlines the importance of teaching children of preschool years phonological strategies in order to boost their reading skills during early school years.     

The hands have it: number representations in adult deaf signers

This study examines a wide range of numerical representations (i.e., quantity, knowledge of multiplication facts, and use of parity information) in adult deaf signers. We introduce a modified version of the number bisection task, with sequential stimulus presentation, which allows for a systematic examination of mathematical skills in deaf individuals in different modalities (number signs in streaming video vs. Arabic digit displays). Reaction times and accuracy measures indicated that deaf signers make use of several representations simultaneously when bisecting number triplets, paralleling earlier findings in hearing individuals. Furthermore, some differences were obtained between the 2 display modalities, with effects being less prominent in the Arabic digit mode, suggesting that mathematical abilities in deaf signers should be assessed in their native sign language.     

Classroom Interpreting and Visual Information Processing in Mainstream Education for Deaf Students: Live or Memorex?

This study examined visual information processing and learning in classrooms including both deaf and hearing students. Of particular interest were the effects on deaf students' learning of live (three-dimensional) versus video-recorded (two-dimensional) sign language interpreting and the visual attention strategies of more and less experienced deaf signers exposed to simultaneous, multiple sources of visual information. Results from three experiments consistently indicated no differences in learning between three-dimensional and two-dimensional presentations among hearing or deaf students. Analyses of students' allocation of visual attention and the influence of various demographic and experimental variables suggested considerable flexibility in deaf students' receptive communication skills. Nevertheless, the findings also revealed a robust advantage in learning in favor of hearing students.     

The use of visual feedback during signing: evidence from signers with impaired vision

The role of visual feedback during the production of American Sign Language was investigated by comparing the size of signing space during conversations and narrative monologues for normally sighted signers, signers with tunnel vision due to Usher syndrome, and functionally blind signers. The interlocutor for all groups was a normally sighted deaf person. Signers with tunnel vision produced a greater proportion of signs near the face than blind and normally sighted signers, who did not differ from each other. Both groups of visually impaired signers produced signs within a smaller signing space for conversations than for monologues, but we hypothesize that they did so for different reasons. Signers with tunnel vision may align their signing space with that of their interlocutor. In contrast, blind signers may enhance proprioceptive feedback by producing signs within an enlarged signing space for monologues, which do not require switching between tactile and visual signing. Overall, we hypothesize that signers use visual feedback to phonetically calibrate the dimensions of signing space, rather than to monitor language output.     

Recognition of Moving and Static Faces by Young Infants

This study compared 3- to 4-month-olds' recognition of previously unfamiliar faces learned in a moving or a static condition. Infants in the moving condition showed successful recognition with only 30 s familiarization, even when different images of a face were used in the familiarization and test phase (Experiment 1). In contrast, infants in the static condition showed successful recognition only when the familiarization duration was lengthened to 90 s and when the same image was used between the familiarization and test phase (Experiments 2 and 3). Furthermore, presentation of multiple static images of a face did not yield the same level of performance as the moving condition (Experiment 4). These results suggest that facial motion promotes young infants' recognition of unfamiliar faces.     

Interpersonal communication skills of deaf adolescents and their relationship to communication history

As part of a longitudinal study, the conversational skills of 67 deaf adolescents were assessed in spoken English, simultaneous communication (SimCom) and American Sign Language (ASL). Two groups of students were identified on the basis of the communication used in their current educational program: a small group of 16 students in programs using spoken English (oral) and a larger group of 51 students in programs using sign communication (bimodal). Students in spoken English programs had good spoken English skills and limited ASL skills, whereas the reverse was true for students in bimodal programs. Most students demonstrated sufficient skill in one or more systems to meet basic interpersonal communications needs, but not those required for advanced academic discourse. In neither group was spoken English related to ASL skill. SimCom skills were strongly related to spoken English in the oral program group and to ASL in the bimodal program group. Spoken English in adolescence was highly predictable from spoken English in early childhood. Within the bimodal program group, students with deaf parents had better SimCom and ASL skills than those with hearing parents. Among bimodal program students with hearing parents, better SimCom skills (but not ASL skills) were associated with earlier introduction to sign communication in school and to mothers' use of sign communication.     

Reading Difficulties in Adult Deaf Readers of French: Phonological Codes,Not Guilty!

Deaf people often achieve low levels of reading skills. The hypothesis that the use of phonological codes is associated with good reading skills in deaf readers is not yet fully supported in the literature. We investigated skilled and less skilled adult deaf readers' use of orthographic and phonological codes in reading. Experiment 1 used a masked priming paradigm to investigate automatic use of these codes during visual word processing. Experiment 2 used a serial recall task to determine whether orthographic and phonological codes are used to maintain words in memory. Skilled hearing, skilled deaf, and less skilled deaf readers used orthographic codes during word recognition and recall, but only skilled hearing readers relied on phonological codes during these tasks. It is important to note that skilled and less skilled deaf readers performed similarly in both tasks, indicating that reading difficulties in deaf adults may not be linked to the activation of phonological codes during reading.