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Ear, Nose, & Throat Journal May 2024Paradoxical embolism from right-to-left shunting is a common cause of cryptogenic stroke in the young. Circulatory ischemia of the cochlea is closely connected with...
Paradoxical embolism from right-to-left shunting is a common cause of cryptogenic stroke in the young. Circulatory ischemia of the cochlea is closely connected with severe-to-profound sudden sensorineural hearing loss. This study aimed to explore the role of paradoxical embolism in severe-to-profound sudden sensorineural hearing loss in juveniles and young adults. From August 2021 to September 2022, consecutive outpatients under 35 years of age with severe-to-profound sudden hearing loss were included in the study. Routine auditory electrophysiological testing and contrast transcranial Doppler ultrasonography (c-TCD) were conducted, and the results were retrospectively analyzed. Seven patients (age: 19.4 ± 6.5 years) were enrolled, including 5 juveniles and 2 young adults. Three patients had severe deafness, and 4 patients had profound deafness. Right-to-left shunting was detected in all patients through c-TCD. Patent foramen ovale was found in 2 patients while pulmonary arteriovenous fistula was found in 1 patient through contrast transthoracic echocardiography or cardiac catheterization. No patients had precipitating factors for sudden sensorineural hearing loss, and none had abnormalities on head magnetic resonance imaging. Six patients underwent wholeexome sequencing, and no known deafness gene variant was detected. After standard treatment for 1 month, 2, 3, and 2 patients had complete, slight, and no hearing recovery, respectively. Paradoxical embolism is a possible cause of severe-to-profound sudden sensorineural hearing loss in juveniles and young adults. In young patients, c-TCD is an effective screening tool to detect right-to-left shunting, while contrast transthoracic echocardiography is a complementary examination to c-TCD.
PubMed: 38801178
DOI: 10.1177/01455613241250185 -
Frontiers in Psychology 2024The impact of deafness on visual attention has been widely discussed in previous research. It has been noted that deficiencies and strengths of previous research can be...
The impact of deafness on visual attention has been widely discussed in previous research. It has been noted that deficiencies and strengths of previous research can be attributed to temporal or spatial aspects of attention, as well as variations in development and clinical characteristics. Visual attention is categorized into three networks: orienting (exogenous and endogenous), alerting (phasic and tonic), and executive control. This study aims to contribute new neuroscientific evidence supporting this hypothesis. This paper presents a systematic review of the international literature from the past 15 years focused on visual attention in the deaf population. The final review included 24 articles. The function of the orienting network is found to be enhanced in deaf adults and children, primarily observed in native signers without cochlear implants, while endogenous orienting is observed only in the context of gaze cues in children, with no differences found in adults. Results regarding alerting and executive function vary depending on clinical characteristics and paradigms used. Implications for future research on visual attention in the deaf population are discussed.
PubMed: 38800679
DOI: 10.3389/fpsyg.2024.1369941 -
Hearing Research Aug 2024Neurons within a neuronal network can be grouped by bottom-up and top-down influences using synchrony in neuronal oscillations. This creates the representation of...
Neurons within a neuronal network can be grouped by bottom-up and top-down influences using synchrony in neuronal oscillations. This creates the representation of perceptual objects from sensory features. Oscillatory activity can be differentiated into stimulus-phase-locked (evoked) and non-phase-locked (induced). The former is mainly determined by sensory input, the latter by higher-level (cortical) processing. Effects of auditory deprivation on cortical oscillations have been studied in congenitally deaf cats (CDCs) using cochlear implant (CI) stimulation. CI-induced alpha, beta, and gamma activity were compromised in the auditory cortex of CDCs. Furthermore, top-down information flow between secondary and primary auditory areas in hearing cats, conveyed by induced alpha oscillations, was lost in CDCs. Here we used the matching pursuit algorithm to assess components of such oscillatory activity in local field potentials recorded in primary field A1. Additionally to the loss of induced alpha oscillations, we also found a loss of evoked theta activity in CDCs. The loss of theta and alpha activity in CDCs can be directly related to reduced high-frequency (gamma-band) activity due to cross-frequency coupling. Here we quantified such cross-frequency coupling in adult 1) hearing-experienced, acoustically stimulated cats (aHCs), 2) hearing-experienced cats following acute pharmacological deafening and subsequent CIs, thus in electrically stimulated cats (eHCs), and 3) electrically stimulated CDCs. We found significant cross-frequency coupling in all animal groups in > 70% of auditory-responsive sites. The predominant coupling in aHCs and eHCs was between theta/alpha phase and gamma power. In CDCs such coupling was lost and replaced by alpha oscillations coupling to delta/theta phase. Thus, alpha/theta oscillations synchronize high-frequency gamma activity only in hearing-experienced cats. The absence of induced alpha and theta oscillations contributes to the loss of induced gamma power in CDCs, thereby signifying impaired local network activity.
Topics: Animals; Cats; Auditory Cortex; Deafness; Acoustic Stimulation; Gamma Rhythm; Cochlear Implants; Alpha Rhythm; Evoked Potentials, Auditory; Algorithms; Auditory Pathways; Disease Models, Animal; Theta Rhythm
PubMed: 38797035
DOI: 10.1016/j.heares.2024.109032 -
International Journal of Pediatric... Jun 2024The newborn hearing screening (NHS) program was globally established for early hearing loss (HL) identification and intervention. Early intervention is essential to...
OBJECTIVES
The newborn hearing screening (NHS) program was globally established for early hearing loss (HL) identification and intervention. Early intervention is essential to minimize or prevent the negative consequences of HL. In Saudi Arabia, the NHS was officially implemented in 2016. Currently, its impact on the timing of cochlear implantations (CIs) in Saudi Arabia remains unclear, and information on potential hospital-related delays affecting early implantation is lacking. Thus, this study aimed to evaluate the effect of implementing the NHS on age at CI in children with prelingual deafness in a CI center in Saudi Arabia, and to evaluate the hospital timing in the CI process.
METHODS
All pediatric CI users who presented for the first time to the CI committee (CIC) at a tertiary center and received their implants between 2015 and 2022 were enrolled in this study. Date of birth (DOB), date of presentation to the CI committee (DOCIC), and date of CI surgery (DOCIS) were retrospectively reviewed.
RESULTS
In total, 304 CI children were included in the analysis. Approximately 55 % of the children (n = 167) were screened for HL through the NHS, whereas 45 % of the children (n = 137) were born before the launch of the NHS. Both age at the presentation to the CIC (i.e. difference between DOCIC and DOB) and age at implantation (i.e. difference between DOCIS and DOB) were significantly earlier in children who were screened for HL through the NHS than those who were not screened (P < 0.0001). The time difference between the DOCIC and DOCIS was not significantly different between the screened and unscreened children (P > 0.05).
CONCLUSION
The implementation of the NHS in the tertiary center has a significant positive effect on age at presentation to the CIC and age at implantation, but not on the actual CI surgery. Further research is needed to reduce the hospital delays before the actual surgery in order to increase the likelihood of children receiving implantation early in their life.
Topics: Humans; Neonatal Screening; Infant, Newborn; Cochlear Implantation; Female; Retrospective Studies; Male; Saudi Arabia; Infant; Hearing Tests; Child, Preschool; Deafness; Hearing Loss; Time-to-Treatment; Time Factors
PubMed: 38796944
DOI: 10.1016/j.ijporl.2024.111990 -
Sensors (Basel, Switzerland) May 2024Deaf and hard-of-hearing people mainly communicate using sign language, which is a set of signs made using hand gestures combined with facial expressions to make...
Deaf and hard-of-hearing people mainly communicate using sign language, which is a set of signs made using hand gestures combined with facial expressions to make meaningful and complete sentences. The problem that faces deaf and hard-of-hearing people is the lack of automatic tools that translate sign languages into written or spoken text, which has led to a communication gap between them and their communities. Most state-of-the-art vision-based sign language recognition approaches focus on translating non-Arabic sign languages, with few targeting the Arabic Sign Language (ArSL) and even fewer targeting the Saudi Sign Language (SSL). This paper proposes a mobile application that helps deaf and hard-of-hearing people in Saudi Arabia to communicate efficiently with their communities. The prototype is an Android-based mobile application that applies deep learning techniques to translate isolated SSL to text and audio and includes unique features that are not available in other related applications targeting ArSL. The proposed approach, when evaluated on a comprehensive dataset, has demonstrated its effectiveness by outperforming several state-of-the-art approaches and producing results that are comparable to these approaches. Moreover, testing the prototype on several deaf and hard-of-hearing users, in addition to hearing users, proved its usefulness. In the future, we aim to improve the accuracy of the model and enrich the application with more features.
Topics: Sign Language; Humans; Deep Learning; Saudi Arabia; Mobile Applications; Deafness; Persons With Hearing Impairments
PubMed: 38793964
DOI: 10.3390/s24103112 -
Brain Sciences Apr 2024Here, we review the literature on neurotypical individuals and individuals with post-stroke aphasia showing that right-hemisphere regions homologous to language network... (Review)
Review
Here, we review the literature on neurotypical individuals and individuals with post-stroke aphasia showing that right-hemisphere regions homologous to language network and other regions, like the right cerebellum, are activated in language tasks and support language even in healthy people. We propose that language recovery in post-stroke aphasia occurs largely by potentiating the right hemisphere network homologous to the language network and other networks that previously supported language to a lesser degree and by modulating connection strength between nodes of the right-hemisphere language network and undamaged nodes of the left-hemisphere language network. Based on this premise (supported by evidence we review), we propose that interventions should be aimed at potentiating the right-hemisphere language network through Hebbian learning or by augmenting connections between network nodes through neuroplasticity, such as non-invasive brain stimulation and perhaps modulation of neurotransmitters involved in neuroplasticity. We review aphasia treatment studies that have taken this approach. We conclude that further aphasia rehabilitation with this aim is justified.
PubMed: 38790398
DOI: 10.3390/brainsci14050419 -
Bioengineering (Basel, Switzerland) May 2024Optical coherence tomography (OCT) is widely used to probe retinal structure and function. This study investigated the outer retina band (ORB) pattern and reflective...
Optical coherence tomography (OCT) is widely used to probe retinal structure and function. This study investigated the outer retina band (ORB) pattern and reflective intensity for the region between bands 2 and 3 (Dip) in three mouse models of inherited retinal degeneration (Rs1KO, TTLL5KO, RPE65KO) and in human AMD patients from the A2A database. OCT images were manually graded, and reflectivity signals were used to calculate the Dip ratio. Qualitative analyses demonstrated the progressive merging band 2 and band 3 in all three mouse models, leading to a reduction in the Dip ratio compared to wildtype (WT) controls. Gene replacement therapy in Rs1KO mice reverted the ORB pattern to one resembling WT and increased the Dip ratio. The degree of anatomical rescue in these mice was highly correlated with level of transgenic RS1 expression and with the restoration of ERG b-wave amplitudes. While the inner retinal cavity was significantly enlarged in dark-adapted Rs1KO mice, the Dip ratio was not altered. A reduction of the Dip ratio was also detected in AMD patients compared with healthy controls and was also positively correlated with AMD severity on the AMD score. We propose that the ORB and Dip ratio can be used as non-invasive early biomarkers for retina health, which can be used to probe therapeutic gene expression and to evaluate the effectiveness of therapy.
PubMed: 38790316
DOI: 10.3390/bioengineering11050449 -
Genes May 2024CHARGE syndrome, characterized by a distinct set of clinical features, has been linked primarily to mutations in the gene. Initially defined by specific clinical...
CHARGE syndrome, characterized by a distinct set of clinical features, has been linked primarily to mutations in the gene. Initially defined by specific clinical criteria, including coloboma, heart defects, choanal atresia, delayed growth, and ear anomalies, CHARGE syndrome's diagnostic spectrum has broadened since the identification of . Variants in this gene exhibit considerable phenotypic variability, leading to the adoption of the term " disorder" to encompass a wider range of associated symptoms. Recent research has identified variants in individuals with isolated features such as autism spectrum disorder or gonadotropin-releasing hormone deficiency. In this study, we present three cases from two different families exhibiting audiovestibular impairment as the primary manifestation of a variant. We discuss the expanding phenotypic variability observed in -related disorders, highlighting the importance of considering in nonsyndromic hearing loss cases, especially when accompanied by inner ear malformations on MRI. Additionally, we underscore the necessity of genetic counseling and comprehensive clinical evaluation for individuals with variants to ensure appropriate management of associated health concerns.
Topics: Humans; CHARGE Syndrome; DNA Helicases; Male; DNA-Binding Proteins; Female; Mutation; Child; Adult; Phenotype; Pedigree; Child, Preschool; Adolescent
PubMed: 38790272
DOI: 10.3390/genes15050643 -
Genes May 2024Hearing impairment, a rare inherited condition, is notably prevalent in populations with high rates of consanguinity. The most common form observed globally is autosomal...
Hearing impairment, a rare inherited condition, is notably prevalent in populations with high rates of consanguinity. The most common form observed globally is autosomal recessive non-syndromic hearing loss. Despite its prevalence, this genetic disorder is characterized by a substantial genetic diversity, making diagnosis and screening challenging. The emergence of advanced next-generation sequencing (NGS) technologies has significantly advanced the discovery of genes and variants linked to various conditions, such as hearing loss. In this study, our objective was to identify the specific variant causing hearing loss in a family from Syria using clinical exome sequencing. The proband in the family exhibited profound deafness as shown by pure-tone audiometry results. The analysis of the different variants obtained by NGS revealed the presence of a nonsense mutation within the gene. Through Sanger sequencing, we verified that this variant segregates with the disease and was not present in the control population. Moreover, we conducted a comprehensive review of all reported deafness-related mutations and their associated phenotypes. Furthermore, we endeavored to carry out a comparative analysis between the and genes, with the objective of identifying potential factors that could explain the notable discrepancy in mutation frequency between these two genes.
Topics: Humans; Male; Female; Connexin 26; Syria; Deafness; Phenotype; Claudins; Pedigree; Mutation; Exome Sequencing; Adult; Codon, Nonsense; Connexins
PubMed: 38790217
DOI: 10.3390/genes15050588 -
Molecular Autism May 2024Social affective and communication symptoms are central to autism spectrum disorder (ASD), yet their severity differs across toddlers: Some toddlers with ASD display...
BACKGROUND
Social affective and communication symptoms are central to autism spectrum disorder (ASD), yet their severity differs across toddlers: Some toddlers with ASD display improving abilities across early ages and develop good social and language skills, while others with "profound" autism have persistently low social, language and cognitive skills and require lifelong care. The biological origins of these opposite ASD social severity subtypes and developmental trajectories are not known.
METHODS
Because ASD involves early brain overgrowth and excess neurons, we measured size and growth in 4910 embryonic-stage brain cortical organoids (BCOs) from a total of 10 toddlers with ASD and 6 controls (averaging 196 individual BCOs measured/subject). In a 2021 batch, we measured BCOs from 10 ASD and 5 controls. In a 2022 batch, we tested replicability of BCO size and growth effects by generating and measuring an independent batch of BCOs from 6 ASD and 4 control subjects. BCO size was analyzed within the context of our large, one-of-a-kind social symptom, social attention, social brain and social and language psychometric normative datasets ranging from N = 266 to N = 1902 toddlers. BCO growth rates were examined by measuring size changes between 1- and 2-months of organoid development. Neurogenesis markers at 2-months were examined at the cellular level. At the molecular level, we measured activity and expression of Ndel1; Ndel1 is a prime target for cell cycle-activated kinases; known to regulate cell cycle, proliferation, neurogenesis, and growth; and known to be involved in neuropsychiatric conditions.
RESULTS
At the BCO level, analyses showed BCO size was significantly enlarged by 39% and 41% in ASD in the 2021 and 2022 batches. The larger the embryonic BCO size, the more severe the ASD social symptoms. Correlations between BCO size and social symptoms were r = 0.719 in the 2021 batch and r = 0. 873 in the replication 2022 batch. ASD BCOs grew at an accelerated rate nearly 3 times faster than controls. At the cell level, the two largest ASD BCOs had accelerated neurogenesis. At the molecular level, Ndel1 activity was highly correlated with the growth rate and size of BCOs. Two BCO subtypes were found in ASD toddlers: Those in one subtype had very enlarged BCO size with accelerated rate of growth and neurogenesis; a profound autism clinical phenotype displaying severe social symptoms, reduced social attention, reduced cognitive, very low language and social IQ; and substantially altered growth in specific cortical social, language and sensory regions. Those in a second subtype had milder BCO enlargement and milder social, attention, cognitive, language and cortical differences.
LIMITATIONS
Larger samples of ASD toddler-derived BCO and clinical phenotypes may reveal additional ASD embryonic subtypes.
CONCLUSIONS
By embryogenesis, the biological bases of two subtypes of ASD social and brain development-profound autism and mild autism-are already present and measurable and involve dysregulated cell proliferation and accelerated neurogenesis and growth. The larger the embryonic BCO size in ASD, the more severe the toddler's social symptoms and the more reduced the social attention, language ability, and IQ, and the more atypical the growth of social and language brain regions.
Topics: Humans; Autism Spectrum Disorder; Organoids; Male; Female; Child, Preschool; Cerebral Cortex; Social Behavior; Organ Size; Infant; Severity of Illness Index; Brain
PubMed: 38790065
DOI: 10.1186/s13229-024-00602-8