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1.
Assist Technol ; 32(5): 268-276, 2020 09 02.
Article in English | MEDLINE | ID: mdl-30592435

ABSTRACT

Digital terrestrial television currently incorporates accessibility elements for the deaf (closed captions, CCs) and for the blind (audio description and audio navigation), however the deafblind population has particular accessibility needs that to date have not been met. This work presents a technical aid (a mobile application called GoAll) developed to increase the autonomy of deafblind individuals, allowing direct access to content broadcast on digital TV through the reading of CCs either with a mobile device or a Braille display. The information in this study is based on the data generated by the application server during the 5 months it was in operation in Spain as well as data from a usability survey conducted on nine deafblind individuals. The results show that 55% of the people used the application between 5 and 7 days a week and did so in the most popular time slots; those surveyed watch news, movies, documentaries, reality shows, and entertainment shows. Noteworthy is fact that all survey respondents said they felt they had greater autonomy with this application. The limitations of the proposed solution involve two elements: Braille reading (knowledge and speed of reading) and the constraints of CCs, since they are used as an input for technical assistance.


Subject(s)
Access to Information , Deaf-Blind Disorders , Television , Adult , Communication Aids for Disabled , Deaf-Blind Disorders/physiopathology , Deaf-Blind Disorders/psychology , Female , Humans , Male , Middle Aged , Mobile Applications , Surveys and Questionnaires , User-Centered Design
2.
Elife ; 82019 11 04.
Article in English | MEDLINE | ID: mdl-31682224

ABSTRACT

Human Tim8a and Tim8b are members of an intermembrane space chaperone network, known as the small TIM family. Mutations in TIMM8A cause a neurodegenerative disease, Mohr-Tranebjærg syndrome (MTS), which is characterised by sensorineural hearing loss, dystonia and blindness. Nothing is known about the function of hTim8a in neuronal cells or how mutation of this protein leads to a neurodegenerative disease. We show that hTim8a is required for the assembly of Complex IV in neurons, which is mediated through a transient interaction with Complex IV assembly factors, in particular the copper chaperone COX17. Complex IV assembly defects resulting from loss of hTim8a leads to oxidative stress and changes to key apoptotic regulators, including cytochrome c, which primes cells for death. Alleviation of oxidative stress with Vitamin E treatment rescues cells from apoptotic vulnerability. We hypothesise that enhanced sensitivity of neuronal cells to apoptosis is the underlying mechanism of MTS.


Subject(s)
Deaf-Blind Disorders/physiopathology , Dystonia/physiopathology , Electron Transport Complex IV/metabolism , Intellectual Disability/physiopathology , Membrane Transport Proteins/metabolism , Neurons/metabolism , Optic Atrophy/physiopathology , Protein Multimerization , Apoptosis , Apoptosis Regulatory Proteins/metabolism , Cell Line , Copper Transport Proteins/metabolism , Humans , Membrane Transport Proteins/deficiency , Mitochondrial Precursor Protein Import Complex Proteins , Oxidative Stress , Protein Interaction Maps
3.
Assist Technol ; 31(5): 276-285, 2019.
Article in English | MEDLINE | ID: mdl-29482473

ABSTRACT

The purpose of this study is to systematically review published evidence regarding the development, use, and effectiveness of assistive devices and technol ogies that enable internet access for individuals who are deafblind. Eight electronic research databases (CINAHL, Embase, Engineering Village MEDLINE, PsycINFO, PubMed, Cochrane Library, and Web of Science) and three clinical trials registries (ISRCTN Registry, WHO ICTRP, and ClinicalTrials.gov) were searched.Seven articles met the inclusion criteria for this systematic review. The assistive technologies described were in the preliminary stages of development, with only three of the technologies having undergone any testing. The effectiveness of all seven assistive technologies was quantified in this review based on the proposed impacts of internet access on the domains of the World Health Organization's International Classification of Functioning, Disability and Health framework.Internet access technologies for individuals with deafblindness are in the early stages of development and are targeted toward specific functions of the internet. It is imperative that future device development and evaluation seek input from persons who are deafblind. There is also a need to address the gap between academic research, which seeks to develop assistive technology to access the internet and the translation into real-world use of this technology.


Subject(s)
Deaf-Blind Disorders/rehabilitation , Internet Access , Self-Help Devices/supply & distribution , Activities of Daily Living , Communication , Deaf-Blind Disorders/physiopathology , Humans , Interpersonal Relations , Self-Help Devices/classification
4.
Q J Exp Psychol (Hove) ; 71(11): 2325-2333, 2018 Nov.
Article in English | MEDLINE | ID: mdl-30362405

ABSTRACT

In this study, we investigated whether auditory deprivation leads to a more balanced bilateral control of spatial attention in the haptic space. We tested four groups of participants: early deaf, early blind, deafblind, and control (normally hearing and sighted) participants. Using a haptic line bisection task, we found that while normally hearing individuals (even when blind) showed a significant tendency to bisect to the left of the veridical midpoint (i.e., pseudoneglect), deaf individuals did not show any significant directional bias. This was the case of both deaf signers and non-signers, in line with prior findings obtained using a visual line bisection task. Interestingly, deafblind individuals also erred significantly to the left, resembling the pattern of early blind and control participants. Overall, these data critically suggest that deafness induces changes in the hemispheric asymmetry subtending the orientation of spatial attention also in the haptic modality. Moreover, our findings indicate that what counterbalances the right-hemisphere dominance in the control of spatial attention is not the lack of auditory input per se, nor sign language use, but rather the heavier reliance on visual experience induced by early auditory deprivation.


Subject(s)
Bias , Blindness/physiopathology , Deaf-Blind Disorders/physiopathology , Deafness/physiopathology , Functional Laterality/physiology , Space Perception/physiology , Touch Perception/physiology , Adolescent , Adult , Aged , Analysis of Variance , Female , Humans , Male , Middle Aged , Young Adult
5.
J Am Geriatr Soc ; 66(11): 2052-2058, 2018 11.
Article in English | MEDLINE | ID: mdl-30248173

ABSTRACT

This article summarizes the presentations and recommendations of the tenth annual American Geriatrics Society and National Institute on Aging Bench-to-Bedside research conference, "Sensory Impairment and Cognitive Decline," on October 2-3, 2017, in Bethesda, Maryland. The risk of impairment in hearing, vision, and other senses increases with age, and almost 15% of individuals aged 70 and older have dementia. As the number of older adults increases, sensory and cognitive impairments will affect a growing proportion of the population. To limit its scope, this conference focused on sensory impairments affecting vision and hearing. Comorbid vision, hearing, and cognitive impairments in older adults are more common than would be expected by chance alone, suggesting that some common mechanisms might affect these neurological systems. This workshop explored the mechanisms and consequences of comorbid vision, hearing, and cognitive impairment in older adults; effects of sensory loss on the aging brain; and bench-to-bedside innovations and research opportunities. Presenters and participants identified many research gaps and questions; the top priorities fell into 3 themes: mechanisms, measurement, and interventions. The workshop delineated specific research questions that provide opportunities to improve outcomes in this growing population. J Am Geriatr Soc 66:2052-2058, 2018.


Subject(s)
Cognitive Dysfunction/physiopathology , Congresses as Topic , Deaf-Blind Disorders/physiopathology , Geriatrics , National Institute on Aging (U.S.) , Societies, Medical/organization & administration , Aged , Aging/physiology , Brain , Dementia , Female , Humans , Male , United States
6.
Dis Model Mech ; 10(2): 105-118, 2017 02 01.
Article in English | MEDLINE | ID: mdl-28067622

ABSTRACT

A consanguineous family from Pakistan was ascertained to have a novel deafness-dystonia syndrome with motor regression, ichthyosis-like features and signs of sensory neuropathy. By applying a combined strategy of linkage analysis and whole-exome sequencing in the presented family, a homozygous nonsense mutation, c.4G>T (p.Glu2*), in FITM2 was identified. FITM2 and its paralog FITM1 constitute an evolutionary conserved protein family involved in partitioning of triglycerides into cellular lipid droplets. Despite the role of FITM2 in neutral lipid storage and metabolism, no indications for lipodystrophy were observed in the affected individuals. In order to obtain independent evidence for the involvement of FITM2 in the human pathology, downregulation of the single Fitm ortholog, CG10671, in Drosophila melanogaster was pursued using RNA interference. Characteristics of the syndrome, including progressive locomotor impairment, hearing loss and disturbed sensory functions, were recapitulated in Drosophila, which supports the causative nature of the FITM2 mutation. Mutation-based genetic counseling can now be provided to the family and insight is obtained into the potential impact of genetic variation in FITM2.


Subject(s)
Deaf-Blind Disorders/genetics , Drosophila Proteins/genetics , Dystonia/genetics , Ichthyosis/genetics , Intellectual Disability/genetics , Membrane Proteins/genetics , Motor Activity , Mutation/genetics , Optic Atrophy/genetics , Sensory Receptor Cells/pathology , Adiposity , Animals , Audiometry, Pure-Tone , Base Sequence , Child , Codon, Nonsense/genetics , Deaf-Blind Disorders/blood , Deaf-Blind Disorders/physiopathology , Disease Models, Animal , Drosophila Proteins/metabolism , Drosophila melanogaster/genetics , Dystonia/blood , Dystonia/physiopathology , Female , Gene Expression Regulation , Gene Knockdown Techniques , HEK293 Cells , Hearing Loss/genetics , Homozygote , Humans , Ichthyosis/complications , Ichthyosis/physiopathology , Intellectual Disability/blood , Intellectual Disability/physiopathology , Lipid Droplets/metabolism , Liver/metabolism , Locomotion , Male , Membrane Proteins/metabolism , Optic Atrophy/blood , Optic Atrophy/physiopathology , Pedigree , Exome Sequencing , Young Adult
7.
Am Ann Deaf ; 161(4): 444-453, 2016.
Article in English | MEDLINE | ID: mdl-27818400

ABSTRACT

Social-emotional development is important to personal adjustment and well-being. Little has been written about social-emotional development in children and youth who are deafblind. The authors discuss factors in typical social-emotional development-attachment, empathy, and friendships-and how they may be challenged in children who are deaf-blind. Also reviewed are factors that place children who are deafblind at risk for delays in social-emotional development. Finally, the possible benefits of inclusion to the social-emotional development of children who are deafblind are examined.


Subject(s)
Child Development , Deaf-Blind Disorders/psychology , Adolescent , Child , Deaf-Blind Disorders/physiopathology , Emotional Intelligence , Humans , Social Behavior
8.
Brain Dev ; 38(10): 954-958, 2016 Nov.
Article in English | MEDLINE | ID: mdl-27256512

ABSTRACT

Arts syndrome is characterized by early-onset hypotonia, ataxia, intellectual disability, sensorineural hearing impairment, progressive optic atrophy, and a tendency to develop infections. Arts syndrome is an X-linked disorder caused by a loss-of-function mutation in the PRPS1 gene, which encodes phosphoribosylpyrophosphate synthetase 1. Only three families have been reported. Here, we report another family with Arts syndrome. The initial symptoms of the 1-year-old proband were hypotonia and ataxia, worsening recurrent infection-triggered muscle weakness, motor and intellectual developmental delay, and hearing loss. Both central nervous system involvement and peripheral neuropathy were demonstrated. His three maternal uncles had died before the age of 3years. A genetic analysis of PRPS1 revealed a novel missense mutation, c.367C>G (p.His123Asp). PRPS enzymatic activity was markedly reduced in the patient. His mother was supposed to be an asymptomatic carrier. Arts syndrome should be included in the differential diagnosis of infantile hypotonia and weakness aggravated by recurrent infection with a family history of X-linked inheritance.


Subject(s)
Ataxia/genetics , Deaf-Blind Disorders/genetics , Genetic Diseases, X-Linked/genetics , Mutation, Missense , Ribose-Phosphate Pyrophosphokinase/genetics , Ataxia/diagnostic imaging , Ataxia/physiopathology , Ataxia/therapy , Brain/diagnostic imaging , Deaf-Blind Disorders/diagnostic imaging , Deaf-Blind Disorders/physiopathology , Deaf-Blind Disorders/therapy , Family , Genetic Diseases, X-Linked/diagnostic imaging , Genetic Diseases, X-Linked/physiopathology , Genetic Diseases, X-Linked/therapy , Humans , Infant , Male , Neural Conduction/genetics , Pedigree
9.
Stereotact Funct Neurosurg ; 94(2): 123-5, 2016.
Article in English | MEDLINE | ID: mdl-27100856

ABSTRACT

BACKGROUND: The prevalence of deafness-dystonia syndrome (DDS) is relatively low. To our knowledge, only 2 cases of this syndrome treated with deep brain stimulation (DBS) have been reported. OBJECTIVES: We present a patient with DDS of unknown cause, refractory to medical treatment, who has been successfully treated with DBS of the internal globus pallidus (DBS-GPi) and followed up for 4 years. METHODS: A 21-year-old male, with progressive bilateral sensorineural hearing loss since the age of 3, developed dystonic movements at the age of 12. The patient presented with progressive segmental craniocervical dystonia with jaw-opening, tongue protrusion, retrocollis and gradual overflow including upper limb dystonia. Pharmacological therapy was ineffective. At the age of 17, the patient's condition deteriorated with the risk of developing a dystonic state. RESULTS: DBS-GPi implantation resulted in a striking improvement. The Burke-Marsden-Fahn Dystonia Rating Scale (BMFDRS) score improved from 75 points before the surgery to 10 points at 3 months after DBS-GPi implantation. Neurological examination at the age of 21 showed mild dystonic movements, mainly oromandibular dystonia (BMFDRS: 15 points). The clinical phenotype of our patient was consistent with Mohr-Tranebjaerg syndrome (MTS). We performed genetic analysis of the TIMM8A gene (the only gene in which mutations are known to cause MTS), but the result was negative; however, other potentially new mutations have to be considered. CONCLUSIONS: Based on our case with the longest reported follow-up of 4 years and 2 earlier reports, we advise to consider DBS-GPi in patients with DDS with unsatisfactory effect of pharmacological treatment.


Subject(s)
Deaf-Blind Disorders/diagnosis , Deaf-Blind Disorders/surgery , Deep Brain Stimulation/trends , Dystonia/diagnosis , Dystonia/surgery , Globus Pallidus/surgery , Intellectual Disability/diagnosis , Intellectual Disability/surgery , Optic Atrophy/diagnosis , Optic Atrophy/surgery , Video Recording/trends , Adult , Child , Deaf-Blind Disorders/physiopathology , Dystonia/physiopathology , Follow-Up Studies , Humans , Intellectual Disability/physiopathology , Male , Optic Atrophy/physiopathology , Time Factors , Treatment Outcome , Young Adult
10.
Ear Hear ; 35(6): 633-40, 2014.
Article in English | MEDLINE | ID: mdl-25127322

ABSTRACT

OBJECTIVES: The aims of this study were (i) to determine the magnitude of the interaural level differences (ILDs) that remain after cochlear implant (CI) signal processing and (ii) to relate the ILDs to the pattern of errors for sound source localization on the horizontal plane. DESIGN: The listeners were 16 bilateral CI patients fitted with MED-EL CIs and 34 normal-hearing listeners. The stimuli were wideband, high-pass, and low-pass noise signals. ILDs were calculated by passing signals, filtered by head-related transfer functions (HRTFs) to a Matlab simulation of MED-EL signal processing. RESULTS: For the wideband signal and high-pass signals, maximum ILDs of 15 to 17 dB in the input signal were reduced to 3 to 4 dB after CI signal processing. For the low-pass signal, ILDs were reduced to 1 to 2 dB. For wideband and high-pass signals, the largest ILDs for ±15 degree speaker locations were between 0.4 and 0.7 dB; for the ±30 degree speaker locations between 0.9 and 1.3 dB; for the 45 degree speaker locations between 2.4 and 2.9 dB; for the ±60 degree speaker locations, between 3.2 and 4.1 dB; and for the ±75 degree speaker locations between 2.7 and 3.4 dB. All of the CI patients in all the stimulus conditions showed poorer localization than the normal-hearing listeners. Localization accuracy for the CI patients was best for the wideband and high-pass signals and was poorest for the low-pass signal. CONCLUSIONS: Localization accuracy was related to the magnitude of the ILD cues available to the normal-hearing listeners and CI patients. The pattern of localization errors for the CI patients was related to the magnitude of the ILD differences among loudspeaker locations. The error patterns for the wideband and high-pass signals, suggest that, for the conditions of this experiment, patients, on an average, sorted signals on the horizontal plane into four sectors-on each side of the midline, one sector including 0, 15, and possibly 30 degree speaker locations, and a sector from 45 degree speaker locations to 75 degree speaker locations. The resolution within a sector was relatively poor.


Subject(s)
Cochlear Implantation/methods , Deaf-Blind Disorders/rehabilitation , Signal Processing, Computer-Assisted , Sound Localization , Adult , Aged , Case-Control Studies , Cochlear Implants , Deaf-Blind Disorders/physiopathology , Female , Humans , Male , Speech Perception , Young Adult
11.
Otol Neurotol ; 34(3): 507-15, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23446327

ABSTRACT

INTRODUCTION: Children with dual sensory impairments are receiving cochlear implants; however, little is known regarding their language outcomes. MATERIALS AND METHODS: Children between the ages of 6 months and 8 years with dual sensory impairment and cochlear implant(s) were recruited from across the United States to participate in an evaluation of language skills using the Reynell-Zinkin Developmental Scales, a tool validated on children with vision impairment and adapted for children with hearing loss. Basic demographic information was also collected from care givers. RESULTS: Ninety-one children completed assessments after implantation. For receptive language abilities, 32% of children obtained a level of sound detection, 15% obtained the ability to understand simple words, 21% could identify words, 5% could follow simple directions, and 22% could follow directions related to the functional use of objects. Four children had no response to sound after cochlear implantation. For expressive language abilities, 49% only had sound production skills, 9% could jargon, 18% could communicate with some words, 12% could communicate with simple sentences, and 12% could communicate with complex sentences. Children with lower developmental ages (or quotients) tended to obtain lower level expressive language skills such as sound production and jargoning. Developmental abilities, rather than age at implant, were the most robust predictor associated with outcomes. DISCUSSION: This information can guide cochlear implant centers when discussing outcomes with families in the cochlear implant candidacy process. There is great heterogeneity in outcomes and caution should be used in discussing possible language outcomes for children with dual sensory impairments.


Subject(s)
Cochlear Implantation , Cochlear Implants , Deaf-Blind Disorders/surgery , Language Development , Speech Perception/physiology , Speech/physiology , Child , Child, Preschool , Communication , Deaf-Blind Disorders/physiopathology , Female , Humans , Infant , Language , Male , Treatment Outcome , Vocabulary
12.
MEDICC Rev ; 15(1): 16-22, 2013 01.
Article in English | MEDLINE | ID: mdl-23396237

ABSTRACT

INTRODUCTION: Cross-modal plasticity has been extensively studied in deaf adults with neuroimaging studies, yielding valuable results. A recent study in our laboratory with deaf-blind children found evidence of cross-modal plasticity, revealed in over-representation of median nerve somatosensory evoked potentials (SEP N20) in left hemisphere parietal, temporal and occipital regions. This finding led to asking whether SEP N20 changes are peculiar to deaf-blindness or are also present in sighted deaf children. OBJECTIVE: Assess cross-modal plasticity in deaf child cochlear implant candidates using neurophysiological techniques (visual evoked potentials and median nerve somatosensory evoked potentials). METHODS: Participants were 14 prelingually deaf children assessed in the Cuban Cochlear Implant Program. Flash visual-evoked potentials and SEP N20 were recorded at 19 scalp recording sites. Topographic maps were obtained and compared to those of control group children with normal hearing. Analysis took into account duration of hearing loss. RESULTS: Topographic maps of flash visual-evoked potentials did not show changes in deaf child cochlear implant candidates. However, SEP N20 from right median nerve stimulation did show changes from expansion of cortical activation into the left temporal region in deaf children aged ≥7 years, which was interpreted as neurophysiological evidence of cross-modal plasticity, not previously described for this technique and type of somatosensory stimulus. We interpret this finding as due in part to duration of deafness, particularly related to handedness, since expansion was selective for the left hemisphere in the children, who were all right-handed. CONCLUSIONS: Cortical over-representation of SEP N20 in the left temporal region is interpreted as evidence of cross-modal plasticity that occurs if the deaf child does not receive a cochlear implant early in life-before concluding the critical period of neural development-and relies on sign language for communication.


Subject(s)
Cochlear Implantation , Deafness/physiopathology , Evoked Potentials, Somatosensory/physiology , Evoked Potentials, Visual/physiology , Neuronal Plasticity/physiology , Adolescent , Case-Control Studies , Child , Child, Preschool , Cuba , Deaf-Blind Disorders/physiopathology , Deep Brain Stimulation , Excitatory Postsynaptic Potentials/physiology , Female , Hearing Loss, Sensorineural/physiopathology , Humans , Male , Median Nerve/physiopathology , Prospective Studies
13.
Mov Disord ; 27(8): 1034-40, 2012 Jul.
Article in English | MEDLINE | ID: mdl-22736418

ABSTRACT

Mohr-Tranebjaerg syndrome (MTS) is an X-linked recessive disorder characterized by deafness and dystonia. However the phenotypic expression of dystonia has not been systematically defined. We report clinical, neurophysiological, and ophthalmological data on 6 subjects from 3 Australian kindreds, including 2 with novel mutations, together with a systematic review of the literature, in order to define the phenotypic expression of dystonia. Profound hearing impairment in affected males develops by infancy and precedes the development of dystonia, which varies in time of onset from the first to the sixth decades, with a peak in the second and third decades. Dystonia in MTS tends to be focal, segmental, or multifocal in distribution at onset, with a predilection for the upper body, variably involving the head, neck, and upper limbs. The majority of patients have progression or generalization of their dystonia regardless of age of onset. Within our 3 kindreds, we observed relative intrafamilial homogeneity but interfamilial variation. The median time to the development of moderate-severely disabling dystonia in these subjects was 11 years. Associated features included progressive cognitive decline, pyramidal signs, and in 1 patient, gait freezing and postural instability. Optic atrophy and cortical visual impairment were both observed. We report for the first time a female patient who developed multiple disabling neurological complications of MTS. Our findings more clearly define and expand the phenotype of both the dystonia and other neurological features of MTS and have implications for the diagnosis and management of this condition.


Subject(s)
Deaf-Blind Disorders/genetics , Deaf-Blind Disorders/physiopathology , Dystonia/genetics , Dystonia/physiopathology , Intellectual Disability/genetics , Intellectual Disability/physiopathology , Optic Atrophy/genetics , Optic Atrophy/physiopathology , Adolescent , Adult , Age of Onset , Australia , Child , Child, Preschool , Cognition Disorders/etiology , Deaf-Blind Disorders/psychology , Disease Progression , Dystonia/psychology , Evoked Potentials, Somatosensory , Evoked Potentials, Visual , Exons , Female , Humans , Infant , Intellectual Disability/etiology , Intellectual Disability/psychology , Introns , Magnetic Resonance Imaging , Male , Membrane Transport Proteins/genetics , Middle Aged , Mitochondrial Precursor Protein Import Complex Proteins , Mutation , Neuropsychological Tests , Optic Atrophy/psychology , Pedigree , Sex Characteristics , Young Adult
14.
MEDICC Rev ; 14(2): 23-9, 2012 04.
Article in English | MEDLINE | ID: mdl-22580550

ABSTRACT

INTRODUCTION: Studies of neuroplasticity have shown that the brain's neural networks change in the absence of sensory input such as hearing or vision. However, little is known about what happens when both sensory modalities are lost (deaf-blindness). Hence, this study of cortical reorganization in visually-impaired child cochlear implant (CI) candidates. OBJECTIVE: Assess cross-modal plasticity, specifically cortical reorganization for tactile representation in visually-impaired child CI candidates, through study of topography of somatosensory evoked potentials (SEP). METHODS: From April through September 2005, SEP from median and tibial nerve electrical stimulation were studied in 12 visually-impaired child CI candidates aged 3-15 years and 23 healthy controls. Following placement of 19 recording electrodes using the International 10-20 System , SEP were recorded and then processed. Topographic maps were obtained for SEP N20 (median nerve) and SEP P40 (tibial nerve), permitting assessment of cortical reorganization by comparing visually-impaired, deaf children's maps with those of healthy children by means of visual inspection and statistical comparison using a permutation test. RESULTS: SEP N20 topography was significantly more extensive in visually-impaired child CI candidates than in healthy children. An asymmetrical pattern occurred from the expansion of hand tactile activation into the temporal and occipital regions in the left hemisphere on right median nerve stimulation. This did not occur for SEP P40 on tibial nerve stimulation (right and left). Magnitude of expanded SEP N20 response was related to severity of visual impairment and longer duration of dual sensory loss. CONCLUSIONS: Changes in SEP N20 topography are evidence of cross-modal plasticity in visually-impaired child CI candidates, appearing to result from a complex interaction between severity of visual impairment and duration of multisensory deprivation.


Subject(s)
Cochlear Implants , Deaf-Blind Disorders/physiopathology , Evoked Potentials, Somatosensory/physiology , Neuronal Plasticity/physiology , Adolescent , Case-Control Studies , Child , Child, Preschool , Cochlear Implants/psychology , Cuba , Deaf-Blind Disorders/rehabilitation , Female , Humans , Male , Prospective Studies , Tibial Nerve/physiopathology
15.
Ophthalmic Physiol Opt ; 32(3): 242-51, 2012 May.
Article in English | MEDLINE | ID: mdl-22348651

ABSTRACT

PURPOSE: Demographic changes are increasing the number of older adults with combined age-related vision and hearing loss, while medical advances increase the survival probability of children with congenital dual (or multiple) impairments due to pre-maturity or rare hereditary diseases. Rehabilitation services for these populations are highly in demand since traditional uni-sensory rehabilitation approaches using the other sense to compensate are not always utilizable. Very little is currently known about the client population characteristics with dual sensory impairment. The present study provides information about demographic and sensory variables of persons in the Montreal region that were receiving rehabilitation for dual impairment in December 2010. This information can inform researchers, clinicians, educators, as well as administrators about potential research and service delivery priorities. METHOD: A chart review of all client files across the three rehabilitation agencies that offer integrated dual sensory rehabilitation services in Montreal provided data on visual acuity, visual field, hearing detection thresholds, and demographic variables. RESULTS: The 209 males and 355 females ranged in age from 4months to 105years (M=71.9, S.D.=24.6), indicating a prevalence estimate for dual sensory impairment at 15/100000. Only 5.7% were under 18years of age, while 69.1% were over the age of 65years, with 43.1% over the age of 85years. The diagnostic combination that accounted for 31% of the entire sample was age-related macular degeneration with presbycusis. Their visual and auditory measures indicated that older adults were likely to fall into moderate to severe levels of impairment on both measures. Individuals with Usher Syndrome comprised 20.9% (n=118) of the sample. CONCLUSION: The age distribution in this sample of persons with dual sensory impairment indicates that service delivery planning will need to strongly consider the growing presence of older adults as the baby-boomers approach retirement age. The distribution of their visual and auditory limits indicates that the large majority of this client group has residual vision and hearing that can be maximized in the rehabilitation process in order to restore functional abilities and social participation. Future research in this area should identify the specific priorities in both rehabilitation and research in individuals affected with combined vision and hearing loss.


Subject(s)
Deaf-Blind Disorders/rehabilitation , Adolescent , Adult , Age Distribution , Aged , Aged, 80 and over , Auditory Threshold/physiology , Child , Child, Preschool , Deaf-Blind Disorders/epidemiology , Deaf-Blind Disorders/physiopathology , Female , Humans , Infant , Macular Degeneration/epidemiology , Macular Degeneration/physiopathology , Macular Degeneration/rehabilitation , Male , Middle Aged , Presbycusis/epidemiology , Presbycusis/physiopathology , Presbycusis/rehabilitation , Prevalence , Quebec/epidemiology , Sex Distribution , Usher Syndromes/epidemiology , Usher Syndromes/physiopathology , Usher Syndromes/rehabilitation , Visual Acuity/physiology , Visual Fields/physiology , Young Adult
16.
Clin Genet ; 78(1): 11-20, 2010 Jul.
Article in English | MEDLINE | ID: mdl-20507341

ABSTRACT

In humans, heterozygous mutations in the adenosine triphosphate-dependent chromatin remodeling gene CHD7 cause CHARGE syndrome, a common cause of deaf-blindness, balance disorders, congenital heart malformations, and olfactory dysfunction with an estimated incidence of approximately 1 in 10,000 newborns. The clinical features of CHARGE in humans and mice are highly variable and incompletely penetrant, and most mutations appear to result in haploinsufficiency of functional CHD7 protein. Mice with heterozygous loss of function mutations in Chd7 are a good model for CHARGE syndrome, and analyses of mouse mutant phenotypes have begun to clarify a role for CHD7 during development and into adulthood. Chd7 heterozygous mutant mice have postnatal delayed growth, inner ear malformations, anosmia/hyposmia, and craniofacial defects, and Chd7 homozygous mutants are embryonic lethal. A central question in developmental biology is how chromodomain proteins like CHD7 regulate important developmental processes, and whether they directly activate or repress downstream gene transcription or act more globally to alter chromatin structure and/or function. CHD7 is expressed in a wide variety of tissues during development, suggesting that it has tissue-specific and developmental stage-specific roles. Here, we review recent and ongoing analyses of CHD7 function in mouse models and cell-based systems. These studies explore tissue-specific effects of CHD7 deficiency, known CHD7 interacting proteins, and downstream target sites for CHD7 binding. CHD7 is emerging as a critical regulator of important developmental processes in organs affected by human CHARGE syndrome.


Subject(s)
DNA Helicases/physiology , DNA-Binding Proteins/physiology , Deaf-Blind Disorders/physiopathology , Abnormalities, Multiple , Animals , DNA Helicases/deficiency , DNA-Binding Proteins/deficiency , Growth and Development , Humans , Mice , Syndrome
17.
Cochlear Implants Int ; 9(4): 177-85, 2008 Dec.
Article in English | MEDLINE | ID: mdl-18844322

ABSTRACT

This study, using positron emission tomography, investigates the cortical activation generated by auditory stimulation in two congenitally blind cochlear implant users. In the patient with a relatively short history of deafness, activity increased in both auditory cortices and fell in the visual cortices. The patient with a longer period of deafness had greater activation of the visual cortices than the auditory cortices. A similar pattern of activity was seen when this patient subsequently had a second cochlear implant inserted into the opposite ear. The neural pathways formed after the restoration of auditory input in the congenitally blind can activate either the auditory or visual cortices. We suggest that the visual cortical activation demonstrated is of functional significance.


Subject(s)
Auditory Cortex/physiopathology , Cochlear Implants , Deaf-Blind Disorders/physiopathology , Deaf-Blind Disorders/rehabilitation , Neuronal Plasticity , Visual Cortex/physiopathology , Acoustic Stimulation , Adult , Humans , Positron-Emission Tomography
18.
Trends Amplif ; 11(4): 219-26, 2007 Dec.
Article in English | MEDLINE | ID: mdl-18003865

ABSTRACT

This article provides an overview of some of the problems and possible solutions surrounding the neglected issue of combined vision and hearing deficits. The subject is treated by considering each subpopulation, ranging from those who have no residual vision or hearing to those with mild coexisting vision and hearing losses. An attempt is made to relate the different types of visual deficit to the likely problems encountered in real-life activities, such as communication and travel, among individuals who also have a hearing impairment. The assessment and appropriate referral of patients with these combined deficits is discussed, including the interpretation of visual test results and the importance of factors other than standard visual acuity. Speculation is offered on potential strategies and solutions for rehabilitation as well as the need for future research and improvements in service delivery.


Subject(s)
Activities of Daily Living , Deaf-Blind Disorders/rehabilitation , Persons With Hearing Impairments , Vision Tests , Visually Impaired Persons , Cost of Illness , Deaf-Blind Disorders/diagnosis , Deaf-Blind Disorders/physiopathology , Humans , Interdisciplinary Communication , Patient Care Team , Quality of Life , Referral and Consultation , Severity of Illness Index
19.
Trends Amplif ; 11(4): 243-58, 2007 Dec.
Article in English | MEDLINE | ID: mdl-18003868

ABSTRACT

Dual sensory impairment (DSI) refers to the presence of both hearing loss and vision loss. The occurrence of DSI is particularly prevalent among the aging population, with studies showing between 9% and 21% of adults older than 70 years having some degree of DSI. Despite this, there is little direction regarding recommended clinical practice and rehabilitation of individuals with DSI. It is assumed that the problems encountered by individuals with DSI are considerably greater than the effects of vision impairment or hearing impairment alone, because when these two sensory impairments are combined, the individual is seriously deprived of compensatory strategies that make use of the nonimpaired sense. In this article, the literature available regarding DSI is summarized, and research needs regarding rehabilitation strategies are outlined and discussed. Simple suggestions for addressing DSI are provided that use available tools and technology.


Subject(s)
Correction of Hearing Impairment , Deaf-Blind Disorders/rehabilitation , Persons With Hearing Impairments , Visually Impaired Persons , Activities of Daily Living , Age Factors , Aged , Biomedical Research , Cognition , Communication , Cost of Illness , Deaf-Blind Disorders/physiopathology , Deaf-Blind Disorders/psychology , Equipment Design , Hearing Aids , Humans , Life Style , Motor Skills , Practice Guidelines as Topic , Professional-Patient Relations , Quality of Life
20.
Am Ann Deaf ; 151(3): 336-44, 2006.
Article in English | MEDLINE | ID: mdl-17087444

ABSTRACT

Empirical data on the development of interaction, communication, and language in deafblind children is very rare. To fill this gap, a case study was conducted in which the interaction between a teacher and a deafblind boy age 3 years 4 months was analyzed. Sequential analysis of their interaction confirmed some general clinical impressions about interaction with deafblind children, and provided the basis for suggestions on how the interaction pattern might be changed.


Subject(s)
Deaf-Blind Disorders/psychology , Faculty , Interpersonal Relations , Persons With Hearing Impairments/psychology , Visually Impaired Persons/psychology , Child, Preschool , Deaf-Blind Disorders/physiopathology , Humans , Male , Multivariate Analysis , Video Recording
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