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1.
Assist Technol ; 32(5): 268-276, 2020 09 02.
Artículo en Inglés | MEDLINE | ID: mdl-30592435

RESUMEN

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.


Asunto(s)
Acceso a la Información , Trastornos Sordoceguera , Televisión , Adulto , Equipos de Comunicación para Personas con Discapacidad , Trastornos Sordoceguera/fisiopatología , Trastornos Sordoceguera/psicología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Aplicaciones Móviles , Encuestas y Cuestionarios , Diseño Centrado en el Usuario
2.
Elife ; 82019 11 04.
Artículo en Inglés | MEDLINE | ID: mdl-31682224

RESUMEN

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.


Asunto(s)
Trastornos Sordoceguera/fisiopatología , Distonía/fisiopatología , Complejo IV de Transporte de Electrones/metabolismo , Discapacidad Intelectual/fisiopatología , Proteínas de Transporte de Membrana/metabolismo , Neuronas/metabolismo , Atrofia Óptica/fisiopatología , Multimerización de Proteína , Apoptosis , Proteínas Reguladoras de la Apoptosis/metabolismo , Línea Celular , Proteínas Transportadoras de Cobre/metabolismo , Humanos , Proteínas de Transporte de Membrana/deficiencia , Proteínas del Complejo de Importación de Proteínas Precursoras Mitocondriales , Estrés Oxidativo , Mapas de Interacción de Proteínas
3.
Assist Technol ; 31(5): 276-285, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-29482473

RESUMEN

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.


Asunto(s)
Trastornos Sordoceguera/rehabilitación , Acceso a Internet , Dispositivos de Autoayuda/provisión & distribución , Actividades Cotidianas , Comunicación , Trastornos Sordoceguera/fisiopatología , Humanos , Relaciones Interpersonales , Dispositivos de Autoayuda/clasificación
4.
Q J Exp Psychol (Hove) ; 71(11): 2325-2333, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-30362405

RESUMEN

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.


Asunto(s)
Sesgo , Ceguera/fisiopatología , Trastornos Sordoceguera/fisiopatología , Sordera/fisiopatología , Lateralidad Funcional/fisiología , Percepción Espacial/fisiología , Percepción del Tacto/fisiología , Adolescente , Adulto , Anciano , Análisis de Varianza , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
5.
J Am Geriatr Soc ; 66(11): 2052-2058, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30248173

RESUMEN

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.


Asunto(s)
Disfunción Cognitiva/fisiopatología , Congresos como Asunto , Trastornos Sordoceguera/fisiopatología , Geriatría , National Institute on Aging (U.S.) , Sociedades Médicas/organización & administración , Anciano , Envejecimiento/fisiología , Encéfalo , Demencia , Femenino , Humanos , Masculino , Estados Unidos
6.
Dis Model Mech ; 10(2): 105-118, 2017 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-28067622

RESUMEN

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.


Asunto(s)
Trastornos Sordoceguera/genética , Proteínas de Drosophila/genética , Distonía/genética , Ictiosis/genética , Discapacidad Intelectual/genética , Proteínas de la Membrana/genética , Actividad Motora , Mutación/genética , Atrofia Óptica/genética , Células Receptoras Sensoriales/patología , Adiposidad , Animales , Audiometría de Tonos Puros , Secuencia de Bases , Niño , Codón sin Sentido/genética , Trastornos Sordoceguera/sangre , Trastornos Sordoceguera/fisiopatología , Modelos Animales de Enfermedad , Proteínas de Drosophila/metabolismo , Drosophila melanogaster/genética , Distonía/sangre , Distonía/fisiopatología , Femenino , Regulación de la Expresión Génica , Técnicas de Silenciamiento del Gen , Células HEK293 , Pérdida Auditiva/genética , Homocigoto , Humanos , Ictiosis/complicaciones , Ictiosis/fisiopatología , Discapacidad Intelectual/sangre , Discapacidad Intelectual/fisiopatología , Gotas Lipídicas/metabolismo , Hígado/metabolismo , Locomoción , Masculino , Proteínas de la Membrana/metabolismo , Atrofia Óptica/sangre , Atrofia Óptica/fisiopatología , Linaje , Secuenciación del Exoma , Adulto Joven
7.
Am Ann Deaf ; 161(4): 444-453, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27818400

RESUMEN

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.


Asunto(s)
Desarrollo Infantil , Trastornos Sordoceguera/psicología , Adolescente , Niño , Trastornos Sordoceguera/fisiopatología , Inteligencia Emocional , Humanos , Conducta Social
8.
Brain Dev ; 38(10): 954-958, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27256512

RESUMEN

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.


Asunto(s)
Ataxia/genética , Trastornos Sordoceguera/genética , Enfermedades Genéticas Ligadas al Cromosoma X/genética , Mutación Missense , Ribosa-Fosfato Pirofosfoquinasa/genética , Ataxia/diagnóstico por imagen , Ataxia/fisiopatología , Ataxia/terapia , Encéfalo/diagnóstico por imagen , Trastornos Sordoceguera/diagnóstico por imagen , Trastornos Sordoceguera/fisiopatología , Trastornos Sordoceguera/terapia , Familia , Enfermedades Genéticas Ligadas al Cromosoma X/diagnóstico por imagen , Enfermedades Genéticas Ligadas al Cromosoma X/fisiopatología , Enfermedades Genéticas Ligadas al Cromosoma X/terapia , Humanos , Lactante , Masculino , Conducción Nerviosa/genética , Linaje
9.
Stereotact Funct Neurosurg ; 94(2): 123-5, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27100856

RESUMEN

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.


Asunto(s)
Trastornos Sordoceguera/diagnóstico , Trastornos Sordoceguera/cirugía , Estimulación Encefálica Profunda/tendencias , Distonía/diagnóstico , Distonía/cirugía , Globo Pálido/cirugía , Discapacidad Intelectual/diagnóstico , Discapacidad Intelectual/cirugía , Atrofia Óptica/diagnóstico , Atrofia Óptica/cirugía , Grabación en Video/tendencias , Adulto , Niño , Trastornos Sordoceguera/fisiopatología , Distonía/fisiopatología , Estudios de Seguimiento , Humanos , Discapacidad Intelectual/fisiopatología , Masculino , Atrofia Óptica/fisiopatología , Factores de Tiempo , Resultado del Tratamiento , Adulto Joven
10.
Ear Hear ; 35(6): 633-40, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25127322

RESUMEN

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.


Asunto(s)
Implantación Coclear/métodos , Trastornos Sordoceguera/rehabilitación , Procesamiento de Señales Asistido por Computador , Localización de Sonidos , Adulto , Anciano , Estudios de Casos y Controles , Implantes Cocleares , Trastornos Sordoceguera/fisiopatología , Femenino , Humanos , Masculino , Percepción del Habla , Adulto Joven
11.
Otol Neurotol ; 34(3): 507-15, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23446327

RESUMEN

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.


Asunto(s)
Implantación Coclear , Implantes Cocleares , Trastornos Sordoceguera/cirugía , Desarrollo del Lenguaje , Percepción del Habla/fisiología , Habla/fisiología , Niño , Preescolar , Comunicación , Trastornos Sordoceguera/fisiopatología , Femenino , Humanos , Lactante , Lenguaje , Masculino , Resultado del Tratamiento , Vocabulario
12.
MEDICC Rev ; 15(1): 16-22, 2013 01.
Artículo en Inglés | MEDLINE | ID: mdl-23396237

RESUMEN

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.


Asunto(s)
Implantación Coclear , Sordera/fisiopatología , Potenciales Evocados Somatosensoriales/fisiología , Potenciales Evocados Visuales/fisiología , Plasticidad Neuronal/fisiología , Adolescente , Estudios de Casos y Controles , Niño , Preescolar , Cuba , Trastornos Sordoceguera/fisiopatología , Estimulación Encefálica Profunda , Potenciales Postsinápticos Excitadores/fisiología , Femenino , Pérdida Auditiva Sensorineural/fisiopatología , Humanos , Masculino , Nervio Mediano/fisiopatología , Estudios Prospectivos
13.
Mov Disord ; 27(8): 1034-40, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22736418

RESUMEN

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.


Asunto(s)
Trastornos Sordoceguera/genética , Trastornos Sordoceguera/fisiopatología , Distonía/genética , Distonía/fisiopatología , Discapacidad Intelectual/genética , Discapacidad Intelectual/fisiopatología , Atrofia Óptica/genética , Atrofia Óptica/fisiopatología , Adolescente , Adulto , Edad de Inicio , Australia , Niño , Preescolar , Trastornos del Conocimiento/etiología , Trastornos Sordoceguera/psicología , Progresión de la Enfermedad , Distonía/psicología , Potenciales Evocados Somatosensoriales , Potenciales Evocados Visuales , Exones , Femenino , Humanos , Lactante , Discapacidad Intelectual/etiología , Discapacidad Intelectual/psicología , Intrones , Imagen por Resonancia Magnética , Masculino , Proteínas de Transporte de Membrana/genética , Persona de Mediana Edad , Proteínas del Complejo de Importación de Proteínas Precursoras Mitocondriales , Mutación , Pruebas Neuropsicológicas , Atrofia Óptica/psicología , Linaje , Caracteres Sexuales , Adulto Joven
14.
MEDICC Rev ; 14(2): 23-9, 2012 04.
Artículo en Inglés | MEDLINE | ID: mdl-22580550

RESUMEN

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.


Asunto(s)
Implantes Cocleares , Trastornos Sordoceguera/fisiopatología , Potenciales Evocados Somatosensoriales/fisiología , Plasticidad Neuronal/fisiología , Adolescente , Estudios de Casos y Controles , Niño , Preescolar , Implantes Cocleares/psicología , Cuba , Trastornos Sordoceguera/rehabilitación , Femenino , Humanos , Masculino , Estudios Prospectivos , Nervio Tibial/fisiopatología
15.
Ophthalmic Physiol Opt ; 32(3): 242-51, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22348651

RESUMEN

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.


Asunto(s)
Trastornos Sordoceguera/rehabilitación , Adolescente , Adulto , Distribución por Edad , Anciano , Anciano de 80 o más Años , Umbral Auditivo/fisiología , Niño , Preescolar , Trastornos Sordoceguera/epidemiología , Trastornos Sordoceguera/fisiopatología , Femenino , Humanos , Lactante , Degeneración Macular/epidemiología , Degeneración Macular/fisiopatología , Degeneración Macular/rehabilitación , Masculino , Persona de Mediana Edad , Presbiacusia/epidemiología , Presbiacusia/fisiopatología , Presbiacusia/rehabilitación , Prevalencia , Quebec/epidemiología , Distribución por Sexo , Síndromes de Usher/epidemiología , Síndromes de Usher/fisiopatología , Síndromes de Usher/rehabilitación , Agudeza Visual/fisiología , Campos Visuales/fisiología , Adulto Joven
16.
Clin Genet ; 78(1): 11-20, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20507341

RESUMEN

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.


Asunto(s)
ADN Helicasas/fisiología , Proteínas de Unión al ADN/fisiología , Trastornos Sordoceguera/fisiopatología , Anomalías Múltiples , Animales , ADN Helicasas/deficiencia , Proteínas de Unión al ADN/deficiencia , Crecimiento y Desarrollo , Humanos , Ratones , Síndrome
17.
Cochlear Implants Int ; 9(4): 177-85, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18844322

RESUMEN

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.


Asunto(s)
Corteza Auditiva/fisiopatología , Implantes Cocleares , Trastornos Sordoceguera/fisiopatología , Trastornos Sordoceguera/rehabilitación , Plasticidad Neuronal , Corteza Visual/fisiopatología , Estimulación Acústica , Adulto , Humanos , Tomografía de Emisión de Positrones
18.
Trends Amplif ; 11(4): 219-26, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18003865

RESUMEN

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.


Asunto(s)
Actividades Cotidianas , Trastornos Sordoceguera/rehabilitación , Personas con Deficiencia Auditiva , Pruebas de Visión , Personas con Daño Visual , Costo de Enfermedad , Trastornos Sordoceguera/diagnóstico , Trastornos Sordoceguera/fisiopatología , Humanos , Comunicación Interdisciplinaria , Grupo de Atención al Paciente , Calidad de Vida , Derivación y Consulta , Índice de Severidad de la Enfermedad
19.
Trends Amplif ; 11(4): 243-58, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18003868

RESUMEN

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.


Asunto(s)
Corrección de Deficiencia Auditiva , Trastornos Sordoceguera/rehabilitación , Personas con Deficiencia Auditiva , Personas con Daño Visual , Actividades Cotidianas , Factores de Edad , Anciano , Investigación Biomédica , Cognición , Comunicación , Costo de Enfermedad , Trastornos Sordoceguera/fisiopatología , Trastornos Sordoceguera/psicología , Diseño de Equipo , Audífonos , Humanos , Estilo de Vida , Destreza Motora , Guías de Práctica Clínica como Asunto , Relaciones Profesional-Paciente , Calidad de Vida
20.
Am Ann Deaf ; 151(3): 336-44, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-17087444

RESUMEN

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.


Asunto(s)
Trastornos Sordoceguera/psicología , Docentes , Relaciones Interpersonales , Personas con Deficiencia Auditiva/psicología , Personas con Daño Visual/psicología , Preescolar , Trastornos Sordoceguera/fisiopatología , Humanos , Masculino , Análisis Multivariante , Grabación en Video
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