Genetic counseling for deaf adults: Communication/language and cultural considerations

It has been estimated that at least 50% of congenital or early onset deafness loss has a genetic etiology. Genetic services have traditionally been utilized by hearing parents of deaf children. Deaf adults could also greatly benefit from genetic counseling services. However, many deaf adults do not seek genetic services due in part to the communication/language and cultural differences of this group. Deaf people communicate in various ways including the use of sign language, oral communication, writing, or a combination of these modes. Also, while some deaf individuals are part of the hearing culture, others are part of the Deaf culture which has its own language, values, and traditions. Culturally Deaf individuals do not see themselves as handicapped or disabled. The genetic professional's awareness of the communication/language and cultural needs of this group, as well as their agency's responsibilities under section 504 of the Rehabilitation Act of 1973, may increase the accessibility of genetic services and contribute to the provision of successful genetic counseling for deaf adults.Throughout this paper, the term deaf will be used to denote a person who audiologically has a hearing loss which may range from mild to profound and may be sensorineural, conductive, or mixed. However, the term Deaf is used to denote cultural deafness.     

Contralateral interference and ear advantages for identification of three-element patterns

Recent experience with attempts to test relatively simple patterns such as three-tone sequences in a traditional dichotic-listening paradigm indicates that when such sequences are used for both target and contralateral interference, performance tends to be low in both ears and not useful for measuring or comparing ear advantages in various target conditions. It is reported that tests with a variety of sounds presented contralaterally to three-element patterns show that several such sounds can (1) allow performance in at least one ear to remain above floor values, (2) result in performance in at least one ear that is below ceiling, and (3) reveal ear advantages that are similar in direction and magnitude to those seen with the traditional dichotic paradigm.     

Dorsal stream deficits suggest hidden dyslexia among deaf poor readers: correlated evidence from reduced perceptual speed and elevated coherent motion detection thresholds

Prelingual deafness and developmental dyslexia have confounding developmental effects on reading acquisition. Therefore, standard reading assessment methods for diagnosing dyslexia in hearing people are ineffective for use with deaf people. Recently, Samar, Parasnis, and Berent (2002) reported visual evoked potential evidence that deaf poor readers, compared to deaf good readers, have dorsal stream visual system deficits like those previously found for hearing dyslexics. Here, we report new psychometric and psychophysical evidence that deficits in dorsal stream function, likely involving extrastriate area MT, are associated with relatively poor reading comprehension in deaf adults. Poorer reading comprehension within a group of 23 prelingually deaf adults was associated with lower scores on the Symbol Digit Modality Test, a perceptual speed test commonly used to help identify dyslexia in hearing people. Furthermore, coherent dot motion detection thresholds, which reflect the functional status of area MT, correlated negatively with reading scores in each visual quadrant. Elevated motion thresholds for deaf poor readers were not due to general cognitive differences in IQ but were specifically correlated with poor perceptual speed. With IQ controlled, a highly reliable right visual field advantage for coherent motion detection was found. Additional analyses suggested that the functional status of dorsal stream motion detection mechanisms in deaf people is related to reading comprehension, but the direction and strength of lateralization of those mechanisms is independent of reading comprehension. Our results generally imply that dyslexia is a hidden contributor to relatively poor reading skill within the deaf population and that assessment of dorsal stream function may provide a diagnostic biological marker for dyslexia in deaf people.     

Dissociating linguistic and non-linguistic gesture processing: electrophysiological evidence from American Sign Language

A fundamental advance in our understanding of human language would come from a detailed account of how non-linguistic and linguistic manual actions are differentiated in real time by language users. To explore this issue, we targeted the N400, an ERP component known to be sensitive to semantic context. Deaf signers saw 120 American Sign Language sentences, each consisting of a “frame” (a sentence without the last word; e.g. BOY SLEEP IN HIS) followed by a “last item” belonging to one of four categories: a high-close-probability sign (a “semantically reasonable” completion to the sentence; e.g. BED), a low-close-probability sign (a real sign that is nonetheless a “semantically odd” completion to the sentence; e.g. LEMON), a pseudo-sign (phonologically legal but non-lexical form), or a non-linguistic grooming gesture (e.g. the performer scratching her face). We found significant N400-like responses in the incongruent and pseudo-sign contexts, while the gestures elicited a large positivity.     

The mathematical abilities of children with cochlear implants

Research has shown that cochlear implants give rise to improvements in speech recognition and production in children with profound hearing loss but very few studies have explored mathematical abilities in these children. The current study compared the mathematical abilities of 24 children with cochlear implants (mean age 10 years 1 month) to a control group of 22 hearing children (mean age 9 years 8 months). The math questions were categorized into questions that tapped into arithmetic or geometrical reasoning. It was predicted that the cochlear implant group would perform below the hearing group on the arithmetic questions but not the geometrical reasoning questions. Unexpectedly, the results showed that the cochlear implant group performed significantly below the hearing group on both types of math questions, but that this difference was mediated by language skill as assessed by vocabulary knowledge. The clinical implications of these results and possible future research results are considered.     

Frequency and predictability effects in eye fixations for skilled and less-skilled deaf readers

The illiteracy rate in the deaf population has been alarmingly high for several decades, despite the fact that deaf children go through the standard stages of schooling. Much research addressing this issue has focused on word-level processes, but in the recent years, little research has focused on sentence-levels processes. Previous research (Fischler, 1985) investigated word integration within context in college-level deaf and hearing readers in a lexical decision task following incomplete sentences with targets that were congruous or incongruous relative to the preceding context; it was found that deaf readers, as a group, were more dependent on contextual information than their hearing counterparts. The present experiment extended Fischler's results and investigated the relationship between frequency, predictability, and reading skill in skilled hearing, skilled deaf, and less-skilled deaf readers. Results suggest that only less-skilled deaf readers, and not all deaf readers, rely more on contextual cues to boost word processing. Additionally, early effects of frequency and predictability were found for all three groups of readers, without any evidence for an interaction between frequency and predictability.     

Investigating the face inversion effect in a deaf population using the Dimensions Tasks

Early experience can change the way people process faces. Early deafness provides deaf children with the opportunity to learn sign language, which is likely to alter their face processing strategy. The goal of the current study was to investigate whether early deafness, combined with the sign language experience, was able to change the face processing strategy using the Dimensions Task. In the Face Dimensions Task, configural and featural information were parametrically and independently manipulated in the eye and mouth region of the face. The manipulations for configural information involved changing the distance between the eyes or the distance between the mouth and the nose. The manipulations for featural information involved changing the size of the eyes or the size of the mouth. Similar manipulations were applied in the House Dimensions Task, with top and bottom windows treated as eyes and mouth. In the Face Dimensions Task, both the signing deaf and hearing participants showed a larger inversion effect in the mouth condition than the eye condition. However, as compared to hearing participants, deaf participants showed smaller inversion effect in the mouth condition, because their performance in the inverted mouth condition was not compromised by inversion to the same extent as the hearing participants. In the House Dimensions Task, this effect was not present, suggesting that it was face specific. This effect could be explained by the redistributed attentional resources from the centre to peripheral visual fields of deaf participants.     

Exploring the Relationship Between Deaf Identity Verification Processes and Self-Esteem

Past research has found that self-esteem in deaf individuals is predicted by variables such as the age they become deaf, the type of school they attend, whether they use sign language or another mode of communication, their parents’ hearing status, and their family’s socioeconomic status. This study applies identity control theory and examines the relationship between Deaf identity verification processes and self-esteem. The results show that, when controlling for variables known to relate to self-esteem, deaf individuals’ education and the degree of difficulty they have in verifying self-meanings in social situations are the only significant predictors of variance in self-esteem. The article discusses the study findings and considers the implications for identity control theorists and Deaf studies scholars.     

聋人阅读的眼动研究

聋人读者普遍存在阅读困难,通过眼动技术来探索聋人阅读中的基本问题已成为一种新趋势,聋人读者在阅读过程中存在其独特的眼动模式。在回顾以往聋人阅读眼动研究的基础上,提出了对未来研究的展望:(1)眼动技术的广泛应用是聋人阅读研究的一个新趋势;(2)从跨文化研究视角探究中外聋人阅读加工的异同;(3)考察聋人视觉注意的特点与语言加工之间的关系;(4)通过眼动技术考察聋人读者的手语加工效率。     

Early interactions and the socioemotional development of deaf infants

Studies of the early face-to-face interactions and later attachment behaviours between infants and their caregivers are reviewed, with a particular focus on implications for deaf infants. Since the majority of deaf infants are born to hearing parents, it is to be expected that many parental responses will rely on vocalizations which are inaccessible to the deaf infant. Are other sensory modalities enhanced or used in a compensatory manner by hearing parents so as to make their communication with a deaf infant more effective? Is the deaf infant's heightened need for visual and tactile input adequately met during normal interactions with their caregivers? Does the deaf infant develop the same strategies for signalling distress and coping with separation as does the hearing infant? Although the research literature on this population is sparse, there are beginning to be more reports addressing these questions as early identification becomes increasingly possible. Therefore, this paper will cover issues of the role of eye contact and mutual coordination in early interactions, compensatory parenting behaviours from the perspective of the ‘intuitive parenting’ model, and precursors to later attachment behaviours in deaf infants.