Relationships between spoken word and sign processing in children with cochlear implants

Development of visual sustained selective attention and response inhibition in deaf children

Studies of deaf and hard-of-hearing (henceforth, deaf) children tend to make comparisons with typically hearing children for the purpose of either identifying deficits to be remediated or understanding the impact of auditory deprivation on visual or domain general processing. Here, we eschew these clinical and theoretical aims, seeking instead to understand factors that explain variability in cognitive function within deaf children. A total of 108 bilingual deaf children ages 7-13 years who use both English and American Sign Language (ASL) participated in a longitudinal study of executive function (EF) development. We report longitudinal data from a visual continuous performance task that measured sustained selective attention and response inhibition. Results show that the impact of deafness on these processes is negligible, but that language skills have a positive relationship with both: better English abilities were associated with better selective sustained attention, and better ASL abilities with better response inhibition. The relationship between sustained selective attention and English abilities may reflect the cognitive demands of spoken language acquisition for deaf children, whereas better ASL abilities may promote an "inner voice," associated with improved response inhibition. The current study cannot conclusively demonstrate causality or directionality of effects. However, these data highlight the importance of studies that focus on atypical individuals, for whom the relationships between language and cognition may be different from those observed in typically developing populations.

Predictors of Word and Text Reading Fluency of Deaf Children in Bilingual Deaf Education Programmes

Reading continues to be a challenging task for most deaf children. Bimodal bilingual education creates a supportive environment that stimulates deaf children’s learning through the use of sign language. However, it is still unclear how exposure to sign language might contribute to improving reading ability. Here, we investigate the relative contribution of several cognitive and linguistic variables to the development of word and text reading fluency in deaf children in bimodal bilingual education programmes. The participants of this study were 62 school-aged (8 to 10 years old at the start of the 3-year study) deaf children who took part in bilingual education (using Dutch and Sign Language of The Netherlands) and 40 age-matched hearing children. We assessed vocabulary knowledge in speech and sign, phonological awareness in speech and sign, receptive fingerspelling ability, and short-term memory at time 1 (T1). At times 2 (T2) and 3 (T3), we assessed word and text reading fluency. We found that (1) speech-based vocabulary strongly predicted word and text reading at T2 and T3, (2) fingerspelling ability was a strong predictor of word and text reading fluency at T2 and T3, (3) speech-based phonological awareness predicted word reading accuracy at T2 and T3 but did not predict text reading fluency, and (4) fingerspelling and STM predicted word reading latency at T2 while sign-based phonological awareness predicted this outcome measure at T3. These results suggest that fingerspelling may have an important function in facilitating the construction of orthographical/phonological representations of printed words for deaf children and strengthening word decoding and recognition abilities.

The Role of Multiple Articulatory Channels of Sign-Supported Speech Revealed by Visual Processing

Purpose The use of sign-supported speech (SSS) in the education of deaf students has been recently discussed in relation to its usefulness with deaf children using cochlear implants. To clarify the benefits of SSS for comprehension, 2 eye-tracking experiments aimed to detect the extent to which signs are actively processed in this mode of communication. Method Participants were 36 deaf adolescents, including cochlear implant users and native deaf signers. Experiment 1 attempted to shift observers' foveal attention to the linguistic source in SSS from which most information is extracted, lip movements or signs, by magnifying the face area, thus modifying lip movements perceptual accessibility (magnified condition), and by constraining the visual field to either the face or the sign through a moving window paradigm (gaze contingent condition). Experiment 2 aimed to explore the reliance on signs in SSS by occasionally producing a mismatch between sign and speech. Participants were required to concentrate upon the orally transmitted message. Results In Experiment 1, analyses revealed a greater number of fixations toward the signs and a reduction in accuracy in the gaze contingent condition across all participants. Fixations toward signs were also increased in the magnified condition. In Experiment 2, results indicated less accuracy in the mismatching condition across all participants. Participants looked more at the sign when it was inconsistent with speech. Conclusions All participants, even those with residual hearing, rely on signs when attending SSS, either peripherally or through overt attention, depending on the perceptual conditions. Supplemental Material https://doi.org/10.23641/asha.8121191.

Early Communication Development of Children with Auditory Brainstem Implants

The auditory brainstem implant (ABI) is an auditory sensory device that is surgically placed on the cochlear nucleus of the brainstem for individuals who are deaf but unable to benefit from a cochlear implant (CI) due to anatomical abnormalities of the cochlea and/or eighth nerve, specific disease processes, or temporal bone fractures. In the United States, the Food and Drug Administration has authorized a Phase I clinical trial to determine safety and feasibility of the ABI in up to 10 eligible young children who are deaf and either derived no benefit from the CI or were anatomically unable to receive a CI. In this paper, we describe the study protocol and the children who have enrolled in the study thus far. In addition, we report the scores on speech perception, speech production, and language (spoken and signed) for five children with 1-3 years of assessment post-ABI activation. To date, the results indicate that spoken communication skills are slow to develop and that visual communication remains essential for post-ABI intervention.

An Eye Tracking Study on the Perception and Comprehension of Unimodal and Bimodal Linguistic Inputs by Deaf Adolescents

An eye tracking experiment explored the gaze behavior of deaf individuals when perceiving language in spoken and sign language only, and in sign-supported speech (SSS). Participants were deaf (n = 25) and hearing (n = 25) Spanish adolescents. Deaf students were prelingually profoundly deaf individuals with cochlear implants (CIs) used by age 5 or earlier, or prelingually profoundly deaf native signers with deaf parents. The effectiveness of SSS has rarely been tested within the same group of children for discourse-level comprehension. Here, video-recorded texts, including spatial descriptions, were alternately transmitted in spoken language, sign language and SSS. The capacity of these communicative systems to equalize comprehension in deaf participants with that of spoken language in hearing participants was tested. Within-group analyses of deaf participants tested if the bimodal linguistic input of SSS favored discourse comprehension compared to unimodal languages. Deaf participants with CIs achieved equal comprehension to hearing controls in all communicative systems while deaf native signers with no CIs achieved equal comprehension to hearing participants if tested in their native sign language. Comprehension of SSS was not increased compared to spoken language, even when spatial information was communicated. Eye movements of deaf and hearing participants were tracked and data of dwell times spent looking at the face or body area of the sign model were analyzed. Within-group analyses focused on differences between native and non-native signers. Dwell times of hearing participants were equally distributed across upper and lower areas of the face while deaf participants mainly looked at the mouth area; this could enable information to be obtained from mouthings in sign language and from lip-reading in SSS and spoken language. Few fixations were directed toward the signs, although these were more frequent when spatial language was transmitted. Both native and non-native signers looked mainly at the face when perceiving sign language, although non-native signers looked significantly more at the body than native signers. This distribution of gaze fixations suggested that deaf individuals – particularly native signers – mainly perceived signs through peripheral vision.

Simultaneous communication supports learning in noise by cochlear implant users

OBJECTIVES

This study sought to evaluate the potential of using spoken language and signing together (simultaneous communication, SimCom, sign-supported speech) as a means of improving speech recognition, comprehension, and learning by cochlear implant (CI) users in noisy contexts.

METHODS

Forty eight college students who were active CI users, watched videos of three short presentations, the text versions of which were standardized at the 8^th-grade reading level. One passage was presented in spoken language only, one was presented in spoken language with multi-talker babble background noise, and one was presented via simultaneous communication with the same background noise. Following each passage, participants responded to 10 (standardized) open-ended questions designed to assess comprehension. Indicators of participants' spoken language and sign language skills were obtained via self-reports and objective assessments.

RESULTS

When spoken materials were accompanied by signs, scores were significantly higher than when materials were spoken in noise without signs. Participants' receptive spoken language skills significantly predicted scores in all three conditions; neither their receptive sign skills nor age of implantation predicted performance.

DISCUSSION

Students who are CI users typically rely solely on spoken language in the classroom. The present results, however, suggest that there are potential benefits of simultaneous communication for such learners in noisy settings. For those CI users who know sign language, the redundancy of speech and signs potentially can offset the reduced fidelity of spoken language in noise.

CONCLUSION

Accompanying spoken language with signs can benefit learners who are CI users in noisy situations such as classroom settings. Factors associated with such benefits, such as receptive skills in signed and spoken modalities, classroom acoustics, and material difficulty need to be empirically examined.

Rapid learning of minimally different words in five- to six-year-old children: effects of acoustic salience and hearing impairment

This study investigates the role of acoustic salience and hearing impairment in learning phonologically minimal pairs. Picture-matching and object-matching tasks were used to investigate the learning of consonant and vowel minimal pairs in five- to six-year-old deaf children with a cochlear implant (CI), and children of the same age with normal hearing (NH). In both tasks, the CI children showed clear difficulties with learning minimal pairs. The NH children also showed some difficulties, however, particularly in the picture-matching task. Vowel minimal pairs were learned more successfully than consonant minimal pairs, particularly in the object-matching task. These results suggest that the ability to encode phonetic detail in novel words is not fully developed at age six and is affected by task demands and acoustic salience. CI children experience persistent difficulties with accurately mapping sound contrasts to novel meanings, but seem to benefit from the relative acoustic salience of vowel sounds.

Simultaneous Communication and Cochlear Implants in the Classroom?

This study was designed to evaluate the potential of simultaneous communication (sign and speech together) to support classroom learning by college students who use cochlear implants (CIs). Metacognitive awareness of learning also was evaluated. A within-subjects design involving 40 implant users indicated that the student participants learned significantly more when material was presented via simultaneous communication than spoken language overall, but a statistical interaction indicated that the difference held only with more difficult material. Learning in the speech-only condition was positively related to the students' spoken language skills, their confidence with spoken language, and their receptive simultaneous communication skills. Learning in that condition was negatively related to the age at which the participants learned to sign. Findings were interpreted to indicate that simultaneous communication can be beneficial for classroom learning by college students with CIs, at least with more complex material or when information redundancy is otherwise important. Further research is needed to determine who is likely to benefit in what settings.

Knowledge, experience and practice of SLTs regarding (re)habilitation in deaf children with cochlear implants

OBJECTIVES

To assess the knowledge, experience and practices of speech and language therapists (SLTs) in Greece regarding children with cochlear implants.

METHODS

A special designed questionnaire was originally completed electronically by 313 SLTs via surveymonkey platform.

RESULTS

From the 313 respondents 35% had worked with implanted children, 37% received course training and 44% had participated in post-graduate seminars. Although 96% believe that there are differences in the management of these children, almost 47% of the participants did not have adequate knowledge on the candidacy criteria for implantation and 70% regarding the available technology for implanted children. Knowledge and skills on CI were better for those SLTs who worked with hearing-impairment. Diverse practice models were noted. Interestingly, more than 87% of the participants advocated toward further training and supervision in the field, even the ones who had less than extensive knowledge in working with CI. As for practice, a lack of organizational interdisciplinary structure became evident.

CONCLUSIONS

There is a growing need for well organized professional training and team networks for SLTs in order for them to further improve their knowledge and service delivery to implanted children.

Vocabulary Knowledge of Deaf and Hearing Postsecondary Students

Deaf children generally are found to have smaller English vocabularies than hearing peers, although studies involving children with cochlear implants have suggested that the gap may decrease or disappear with age. Less is known about the vocabularies of deaf and hard-of-hearing (DHH) postsecondary students or how their vocabulary knowledge relates to other aspects of academic achievement. This study used the Peabody Picture Vocabulary Test to examine the vocabulary knowledge of DHH and hearing postsecondary students as well as their awareness (predictions) of that knowledge. Relationships between vocabulary knowledge and print exposure, communication backgrounds, and reading and verbal abilities also were examined. Consistent with studies of children, hearing college students demonstrated significantly larger vocabularies than DHH students both with and without cochlear implants. DHH students were more likely to overestimate their vocabulary knowledge. Vocabulary scores were positively related to reading and verbal abilities but negatively related to sign language abilities. Among DHH students they also were positively related to measures of spoken language ability. Results are discussed in terms of related cognitive abilities, language fluency, and academic achievement of DHH students and implications for postsecondary education.