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1.
J Cardiovasc Electrophysiol ; 35(4): 765-774, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38357859

RESUMEN

INTRODUCTION: Pulsed electric field (PEF) ablation relies on the intersection of a critical voltage gradient with tissue to cause cell death. Field-based lesion formation with PEF technologies may still depend on catheter-tissue contact (CTC). The purpose of this study was to assess the impact of CTC on PEF lesion formation with an investigational large area focal (LAF) catheter in a preclinical model. METHODS: PEF ablation via a 10-spline LAF catheter was used to create discrete right ventricle (RV) lesions and atrial lesion sets in 10 swine (eight acute, two chronic). Local impedance (LI) was used to assess CTC. Lesions were assigned to three cohorts using LI above baseline: no tissue contact (NTC: ≤∆10 Ω, close proximity to tissue), low tissue contact (LTC: ∆11-29 Ω), and high tissue contact (HTC: ≥∆30 Ω). Acute animals were infused with triphenyl tetrazolium chloride (TTC) and killed ≥2 h post-treatment. Chronic animals were remapped 30 days post-index procedure and stained with infused TTC. RESULTS: Mean (± SD) RV treatment sizes between LTC (n = 14) and HTC (n = 17) lesions were not significantly different (depth: 5.65 ± 1.96 vs. 5.68 ± 2.05 mm, p = .999; width: 15.68 ± 5.22 vs. 16.98 ± 4.45 mm, p = .737), while mean treatment size for NTC lesions (n = 6) was significantly smaller (1.67 ± 1.16 mm depth, 5.97 ± 4.48 mm width, p < .05). For atrial lesion sets, acute and chronic conduction block were achieved with both LTC (N = 7) and HTC (N = 6), and NTC resulted in gaps. CONCLUSIONS: PEF ablation with a specialized LAF catheter in a swine model is dependent on CTC. LI as an indicator of CTC may aid in the creation of consistent transmural lesions in PEF ablation.


Asunto(s)
Fibrilación Atrial , Ablación por Catéter , Humanos , Porcinos , Animales , Ablación por Catéter/efectos adversos , Ablación por Catéter/métodos , Atrios Cardíacos , Frecuencia Cardíaca , Ventrículos Cardíacos , Impedancia Eléctrica , Catéteres , Fibrilación Atrial/cirugía
2.
Int J Audiol ; 62(11): 1014-1021, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-36688609

RESUMEN

OBJECTIVES: This study explored the effects of different face masks on school-age children's and young adults' word recognition. DESIGN: Speech recognition thresholds were measured adaptively in a two-talker speech masker using a closed-set picture pointing task. Target words were recorded by a female talker in five conditions: no mask, transparent mask, face shield, N95 mask and surgical mask. STUDY SAMPLES: Thirty children (8-12 years) and 25 adults (18-25 years) with normal hearing. RESULTS: Both children's and adults' word recognition was most negatively impacted by the face shield. Children's recognition was also impaired by the transparent mask. No negative effects were observed for the N95 or surgical mask for either age group. CONCLUSION: School-age children, like young adults, are negatively affected by face masks when recognising speech in a two-talker speech masker, but the effects depend on the type of face mask being worn. Acoustic analyses suggest that the reflective materials used for masks impact speech signal quality and impair word recognition.


Asunto(s)
Percepción del Habla , Habla , Adulto Joven , Humanos , Niño , Femenino , Máscaras , Enmascaramiento Perceptual , Desarrollo Infantil
3.
Ear Hear ; 42(4): 1084-1096, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33538428

RESUMEN

OBJECTIVES: The objectives of the study were to (1) evaluate the impact of hearing loss on children's ability to benefit from F0 differences between target/masker speech in the context of aided speech-in-speech recognition and (2) to determine whether compromised F0 discrimination associated with hearing loss predicts F0 benefit in individual children. We hypothesized that children wearing appropriately fitted amplification would benefit from F0 differences, but they would not show the same magnitude of benefit as children with normal hearing. Reduced audibility and poor suprathreshold encoding that degrades frequency discrimination were expected to impair children's ability to segregate talkers based on F0. DESIGN: Listeners were 9 to 17 year olds with bilateral, symmetrical, sensorineural hearing loss ranging in degree from mild to severe. A four-alternative, forced-choice procedure was used to estimate thresholds for disyllabic word recognition in a 60-dB-SPL two-talker masker. The same male talker produced target and masker speech. Target words had either the same mean F0 as the masker or were digitally shifted higher than the masker by three, six, or nine semitones. The F0 benefit was defined as the difference in thresholds between the shifted-F0 conditions and the unshifted-F0 condition. Thresholds for discriminating F0 were also measured, using a three-alternative, three-interval forced choice procedure, to determine whether compromised sensitivity to F0 differences due to hearing loss would predict children's ability to benefit from F0. Testing was performed in the sound field, and all children wore their personal hearing aids at user settings. RESULTS: Children with hearing loss benefited from an F0 difference of nine semitones between target words and masker speech, with older children generally benefitting more than younger children. Some children benefitted from an F0 difference of six semitones, but this was not consistent across listeners. Thresholds for discriminating F0 improved with increasing age and predicted F0 benefit in the nine-semitone condition. An exploratory analysis indicated that F0 benefit was not significantly correlated with the four-frequency pure-tone average (0.5, 1, 2, and 4 kHz), aided audibility, or consistency of daily hearing aid use, although there was a trend for an association with the low-frequency pure-tone average (0.25 and 0.5 kHz). Comparisons of the present data to our previous study of children with normal hearing demonstrated that children with hearing loss benefitted less than children with normal hearing for the F0 differences tested. CONCLUSIONS: The results demonstrate that children with mild-to-severe hearing loss who wear hearing aids benefit from relatively large F0 differences between target and masker speech during aided speech-in-speech recognition. The size of the benefit increases with increasing age, consistent with previously reported age effects for children with normal hearing. However, hearing loss reduces children's ability to capitalize on F0 differences between talkers. Audibility alone does not appear to be responsible for this effect; aided audibility and degree of loss were not primary predictors of performance. The ability to benefit from F0 differences may be limited by immature central processing or aspects of peripheral encoding that are not characterized in standard clinical assessments.


Asunto(s)
Pérdida Auditiva Sensorineural , Pérdida Auditiva , Percepción del Habla , Adolescente , Niño , Humanos , Masculino , Enmascaramiento Perceptual , Instituciones Académicas , Habla
4.
Ear Hear ; 40(4): 927-937, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30334835

RESUMEN

OBJECTIVES: The objectives of this study were to (1) evaluate the extent to which school-age children benefit from fundamental frequency (F0) differences between target words and competing two-talker speech, and (2) assess whether this benefit changes with age. It was predicted that while children would be more susceptible to speech-in-speech masking compared to adults, they would benefit from differences in F0 between target and masker speech. A second experiment was conducted to evaluate the relationship between frequency discrimination thresholds and the ability to benefit from target/masker differences in F0. DESIGN: Listeners were children (5 to 15 years) and adults (20 to 36 years) with normal hearing. In the first experiment, speech reception thresholds (SRTs) for disyllabic words were measured in a continuous, 60-dB SPL two-talker speech masker. The same male talker produced both the target and masker speech (average F0 = 120 Hz). The level of the target words was adaptively varied to estimate the level associated with 71% correct identification. The procedure was a four-alternative forced-choice with a picture-pointing response. Target words either had the same mean F0 as the masker or it was shifted up by 3, 6, or 9 semitones. To determine the benefit of target/masker F0 separation on word recognition, masking release was computed by subtracting thresholds in each shifted-F0 condition from the threshold in the unshifted-F0 condition. In the second experiment, frequency discrimination thresholds were collected for a subset of listeners to determine whether sensitivity to F0 differences would be predictive of SRTs. The standard was the syllable /ba/ with an F0 of 250 Hz; the target stimuli had a higher F0. Discrimination thresholds were measured using a three-alternative, three-interval forced choice procedure. RESULTS: Younger children (5 to 12 years) had significantly poorer SRTs than older children (13 to 15 years) and adults in the unshifted-F0 condition. The benefit of F0 separations generally increased with increasing child age and magnitude of target/masker F0 separation. For 5- to 7-year-olds, there was a small benefit of F0 separation in the 9-semitone condition only. For 8- to 12-year-olds, there was a benefit from both 6- and 9-semitone separations, but to a lesser degree than what was observed for older children (13 to 15 years) and adults, who showed a substantial benefit in the 6- and 9-semitone conditions. Examination of individual data found that children younger than 7 years of age did not benefit from any of the F0 separations tested. Results for the frequency discrimination task indicated that, while there was a trend for improved thresholds with increasing age, these thresholds were not predictive of the ability to use F0 differences in the speech-in-speech recognition task after controlling for age. CONCLUSIONS: The overall pattern of results suggests that children's ability to benefit from F0 differences in speech-in-speech recognition follows a prolonged developmental trajectory. Younger children are less able to capitalize on differences in F0 between target and masker speech. The extent to which individual children benefitted from target/masker F0 differences was not associated with their frequency discrimination thresholds.


Asunto(s)
Desarrollo Infantil/fisiología , Enmascaramiento Perceptual/fisiología , Discriminación de la Altura Tonal/fisiología , Percepción del Habla/fisiología , Adolescente , Adulto , Niño , Preescolar , Femenino , Voluntarios Sanos , Humanos , Masculino , Prueba del Umbral de Recepción del Habla , Adulto Joven
5.
J Community Health ; 44(1): 192-199, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-29995303

RESUMEN

Policy makers and public health practitioners rarely consider public libraries to be part of the health system, even though they possess several characteristics that suggest unrealized potential to advance population health. This scoping review uses an adapted social determinants framework to categorize current health-related work conducted by public libraries in the United States and to discuss libraries' potential as 'meso-level' community resources to improve population health. Our discussion of libraries contributes to scholarship on place-based health disparities, by emphasizing the potential impact of institutions that are modifiable through social policy-e.g., parks, community centers, schools-and which have a conceptually clear or empirically documented relationship to health.


Asunto(s)
Promoción de la Salud/organización & administración , Bibliotecas/organización & administración , Salud Poblacional/estadística & datos numéricos , Humanos , Salud Pública , Política Pública , Estados Unidos
6.
Environ Monit Assess ; 191(3): 175, 2019 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-30788632

RESUMEN

Management of healthcare waste in low- and middle-income countries lacks a straightforward solution, especially where rural health services are provided. The purpose of our case study was to explore the knowledge and practices of health surveillance assistants operating at rural village health clinics in Ntcheu District, Malawi, with regard to the collection, segregation, transportion, treatment, and disposal of healthcare waste. Data were collected from 81 clinics. The results indicated that while general gaps in both knowledge and practice were observed, sharps (e.g., needles) management was generally being done well. An opportunity for scale-up was found in one clinic, in which local materials had been used to construct a low-cost innovative sharps disposal receptacle that had been modified from a pit latrine design. This study recommends waste management training suitable for rural settings, the promotion of low-cost sharps disposal receptacles using local materials, further opportunities for low-cost incinerators, central waste collection, and encouraging grassroots innovation in healthcare waste management.


Asunto(s)
Monitoreo del Ambiente/métodos , Eliminación de Residuos Sanitarios/métodos , Servicios de Salud Rural/organización & administración , Países en Desarrollo , Monitoreo del Ambiente/economía , Humanos , Incineración , Malaui , Eliminación de Residuos Sanitarios/economía , Agujas , Servicios de Salud Rural/economía , Población Rural
7.
J Acoust Soc Am ; 142(1): EL150, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28764444

RESUMEN

Frequency discrimination was measured in 5- to 11-year-olds and adults with normal hearing. The standard stimulus was either a 250-Hz tone or the syllable /ba/ with a fundamental frequency (F0) of 250 Hz. Target stimuli were higher in frequency than the standard, and the threshold for frequency discrimination was determined adaptively for each of the two stimulus types separately. For both the tone and /ba/ stimuli, thresholds improved approximately linearly with the log of child age, reaching adult levels by 11.5 years of age. There was no evidence of an effect of stimulus type.


Asunto(s)
Conducta Infantil , Desarrollo Infantil , Discriminación en Psicología , Discriminación de la Altura Tonal , Estimulación Acústica , Adulto , Factores de Edad , Audiometría de Tonos Puros , Umbral Auditivo , Niño , Preescolar , Humanos , Psicoacústica , Adulto Joven
8.
Dev Med Child Neurol ; 58(7): 714-20, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-26526690

RESUMEN

AIM: To evaluate the prevalence of organ system disorders and describe healthcare utilization among adults with spina bifida at a regional clinic. METHOD: This study was a structured chart review using the Rochester Health Status Survey-IV. 65 males, 57 females aged 16 to 59 years were seen at the Spina Bifida Center of Central New York between January 2007 and December 2008 (annual hospitalization rate was 15 out of 100). RESULTS: Hospitalizations and acute outpatient visits were associated with having shunted hydrocephalus, whereas visits to the emergency department were associated with having a decubitus ulcer. Logistic regression models revealed that older adults made proportionately fewer visits to primary care providers than younger adults (odds ratio 0.919; p=0.02). Yet for every 1-year increase in age, the odds of being hospitalized increased by 5% (odds ratio 1.051; p=0.03). INTERPRETATION: Adults with spina bifida have multiple organ-system disorders. They have greater difficulty accessing services, and utilize emergency and inpatient healthcare at higher rates than the general population. In the future, adults with spina bifida will require access to more medical care and preventive services if they are to have optimal health, well-being, and functioning.


Asunto(s)
Atención a la Salud/estadística & datos numéricos , Estado de Salud , Disrafia Espinal/fisiopatología , Disrafia Espinal/terapia , Adolescente , Adulto , Derivaciones del Líquido Cefalorraquídeo/métodos , Trastornos del Conocimiento/etiología , Atención a la Salud/métodos , Femenino , Encuestas Epidemiológicas , Hospitalización , Humanos , Hidrocefalia/etiología , Hidrocefalia/cirugía , Masculino , Persona de Mediana Edad , Prevalencia , Factores Sexuales , Disrafia Espinal/epidemiología , Adulto Joven
9.
J Acoust Soc Am ; 139(2): 674-83, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26936551

RESUMEN

Deciphering the auditory scene is a problem faced by many organisms. However, when faced with numerous overlapping sounds from multiple locations, listeners are still able to attribute the individual sound objects to their individual sound-producing sources. Here, the characteristics of sounds important for integrating versus segregating in birds were determined. Budgerigars and zebra finches were trained using operant conditioning procedures on an identification task to peck one key when they heard a whole zebra finch song and to peck another when they heard a zebra finch song missing a middle syllable. Once the birds were trained to a criterion performance level on those stimuli, probe trials were introduced on a small proportion of trials. The probe songs contained modifications of the incomplete training song's missing syllable. When the bird responded as if the probe was a whole song, it suggests they streamed together the altered syllable and the rest of the song. When the bird responded as if the probe was a non-whole song, it suggests they segregated the altered probe from the rest of the song. Results show that some features, such as location and intensity, are more important for segregating than other features, such as timing and frequency.


Asunto(s)
Señales (Psicología) , Pinzones/fisiología , Melopsittacus/fisiología , Percepción de la Altura Tonal , Localización de Sonidos , Vocalización Animal , Estimulación Acústica , Acústica , Animales , Condicionamiento Operante , Femenino , Masculino , Ruido/efectos adversos , Enmascaramiento Perceptual , Psicoacústica , Espectrografía del Sonido , Factores de Tiempo
10.
Percept Mot Skills ; 119(1): 203-14, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25153750

RESUMEN

The aim of this study was to examine the influence of yoga practice on body image satisfaction in men. Male Figure Drawings were used to explore body image satisfaction in yoga beginners (n = 26, M age = 40.3 yr., SD = 11.6), experienced yoga practitioners (n = 22, M age = 46.4 yr., SD = 11.6), and non-yoga practicing aerobic and weight training exercisers (n = 34, M age = 41.2 yr., SD = 11.9). Satisfaction was significantly higher among the yoga groups than the exercisers. There was no statistical difference between the body satisfaction scores of the experienced yoga group and the beginner yoga students. This may suggest that individuals drawn to yoga have greater body satisfaction than exercisers, and that regular yoga practice possibly further increases body satisfaction.


Asunto(s)
Imagen Corporal/psicología , Satisfacción Personal , Yoga/psicología , Adulto , Humanos , Masculino , Persona de Mediana Edad
11.
Online J Issues Nurs ; 19(3): 9, 2014 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-26824157

RESUMEN

Advanced practice nurses have increased in number and public acceptance. Students preparing for these roles require quality clinical education so they are prepared to assume collaborative roles in healthcare settings. Although graduate clinical preceptors have a vitally important role in the clinical education and professional socialization of advanced practice students, there is a paucity of evidence about factors that influence their role commitment. In this article, the authors review the literature related to graduate-level, clinical-preceptor experiences; describe their study of 91 graduate clinical preceptors that identified factors influencing graduate clinical preceptors' role commitment; report and discuss their findings; as well as the limitations of this study. They conclude that the graduate clinical preceptor role needs to be more visible and better integrated into schools of nursing and healthcare organizational structures, and identify the need for intra-professional collaboration among nursing faculty, administrators, and clinicians to facilitate the recruitment, cultivation, and retention of graduate clinical preceptors.


Asunto(s)
Enfermería de Práctica Avanzada , Conducta Cooperativa , Educación de Postgrado en Enfermería , Docentes de Enfermería , Rol de la Enfermera , Preceptoría , Humanos
12.
Front Psychol ; 15: 1369195, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38784624

RESUMEN

Objectives: This study investigated the influence of long-term talker familiarity on speech-in-speech recognition in school-age children, with a specific emphasis on the role of familiarity with the mother's voice as either the target or masker speech. Design: Open-set sentence recognition was measured adaptively in a two-talker masker. Target and masker sentences were recorded by the adult mothers of the child participants. Each child heard sentences spoken by three adult female voices during testing; their own mother's voice (familiar voice) and two unfamiliar adult female voices. Study sample: Twenty-four school age children (8-13 years) with normal hearing. Results: When the target speech was spoken by a familiar talker (the mother), speech recognition was significantly better compared to when the target was unfamiliar. When the masker was spoken by the familiar talker, there was no difference in performance relative to the unfamiliar masker condition. Across all conditions, younger children required a more favorable signal-to-noise ratio than older children. Conclusion: Implicit long-term familiarity with a talker consistently improves children's speech-in-speech recognition across the age range tested, specifically when the target talker is familiar. However, performance remains unaffected by masker talker familiarity. Additionally, while target familiarity is advantageous, it does not entirely eliminate children's increased susceptibility to competing speech.

13.
bioRxiv ; 2024 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-38562832

RESUMEN

Genome-wide association studies (GWAS) and expression analyses implicate noncoding regulatory regions as harboring risk factors for psychiatric disease, but functional characterization of these regions remains limited. We performed capture STARR-sequencing of over 78,000 candidate regions to identify active enhancers in primary human neural progenitor cells (phNPCs). We selected candidate regions by integrating data from NPCs, prefrontal cortex, developmental timepoints, and GWAS. Over 8,000 regions demonstrated enhancer activity in the phNPCs, and we linked these regions to over 2,200 predicted target genes. These genes are involved in neuronal and psychiatric disease-associated pathways, including dopaminergic synapse, axon guidance, and schizophrenia. We functionally validated a subset of these enhancers using mutation STARR-sequencing and CRISPR deletions, demonstrating the effects of genetic variation on enhancer activity and enhancer deletion on gene expression. Overall, we identified thousands of highly active enhancers and functionally validated a subset of these enhancers, improving our understanding of regulatory networks underlying brain function and disease.

14.
bioRxiv ; 2024 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-38562822

RESUMEN

Single-cell genomics is a powerful tool for studying heterogeneous tissues such as the brain. Yet, little is understood about how genetic variants influence cell-level gene expression. Addressing this, we uniformly processed single-nuclei, multi-omics datasets into a resource comprising >2.8M nuclei from the prefrontal cortex across 388 individuals. For 28 cell types, we assessed population-level variation in expression and chromatin across gene families and drug targets. We identified >550K cell-type-specific regulatory elements and >1.4M single-cell expression-quantitative-trait loci, which we used to build cell-type regulatory and cell-to-cell communication networks. These networks manifest cellular changes in aging and neuropsychiatric disorders. We further constructed an integrative model accurately imputing single-cell expression and simulating perturbations; the model prioritized ~250 disease-risk genes and drug targets with associated cell types.

15.
Science ; 384(6698): eadi5199, 2024 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-38781369

RESUMEN

Single-cell genomics is a powerful tool for studying heterogeneous tissues such as the brain. Yet little is understood about how genetic variants influence cell-level gene expression. Addressing this, we uniformly processed single-nuclei, multiomics datasets into a resource comprising >2.8 million nuclei from the prefrontal cortex across 388 individuals. For 28 cell types, we assessed population-level variation in expression and chromatin across gene families and drug targets. We identified >550,000 cell type-specific regulatory elements and >1.4 million single-cell expression quantitative trait loci, which we used to build cell-type regulatory and cell-to-cell communication networks. These networks manifest cellular changes in aging and neuropsychiatric disorders. We further constructed an integrative model accurately imputing single-cell expression and simulating perturbations; the model prioritized ~250 disease-risk genes and drug targets with associated cell types.


Asunto(s)
Encéfalo , Redes Reguladoras de Genes , Trastornos Mentales , Análisis de la Célula Individual , Humanos , Envejecimiento/genética , Encéfalo/metabolismo , Comunicación Celular/genética , Cromatina/metabolismo , Cromatina/genética , Genómica , Trastornos Mentales/genética , Corteza Prefrontal/metabolismo , Corteza Prefrontal/fisiología , Sitios de Carácter Cuantitativo
16.
Am J Audiol ; : 1-16, 2023 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-38056473

RESUMEN

PURPOSE: The goal was to evaluate whether implicit talker familiarization via an interactive computer game, designed for this study, could improve children's word recognition in classroom noise. It was hypothesized that, regardless of age, children would perform better when recognizing words spoken by the talker who was heard during the game they played. METHOD: Using a one-group pretest-posttest experimental design, this study examined the impact of short-term implicit voice exposure on children's word recognition in classroom noise. Implicit voice familiarization occurred via an interactive computer game, played at home for 10 min a day for 5 days. In the game, children (8-12 years) heard one voice, intended to become the "familiar talker." Pre- and postfamiliarization, children identified words in prerecorded classroom noise. Four conditions were tested to evaluate talker familiarity and generalization effects. RESULTS: Results demonstrated an 11% improvement when recognizing words spoken by the voice heard in the game ("familiar talker"). This was observed only for words that were heard in the game and did not generalize to unfamiliarized words. Before familiarization, younger children had poorer recognition than older children in all conditions; however, after familiarization, there was no effect of age on performance for familiarized stimuli. CONCLUSIONS: Implicit short-term exposure to a talker has the potential to improve children's speech recognition. Therefore, leveraging talker familiarity through gameplay shows promise as a viable method for improving children's speech-in-noise recognition. However, given that improvements did not generalize to unfamiliarized words, careful consideration of exposure stimuli is necessary to optimize this approach.

17.
J Speech Lang Hear Res ; 66(1): 400-414, 2023 01 12.
Artículo en Inglés | MEDLINE | ID: mdl-36580582

RESUMEN

PURPOSE: Maturation of the ability to recognize target speech in the presence of a two-talker speech masker extends into early adolescence. This study evaluated whether children benefit from differences in fundamental frequency (f o) contour depth between the target and masker speech, a cue that has been shown to improve recognition in adults. METHOD: Speech stimuli were recorded from talkers using three speaking styles, with f o contour depths that were Flat, Normal, or Exaggerated. Targets were open-set, declarative sentences produced by a female talker, and maskers were two streams of concatenated sentences produced by a second female talker. Listeners were children (ages 5-17 years) and adults (ages 18-24 years) with normal hearing. Each listener was tested in one of the three masker styles paired with all three target styles. Speech recognition thresholds (SRTs) corresponding to 50% correct were estimated by fitting psychometric functions to adaptive track data. RESULTS: For adults, performance did not differ significantly across conditions with matched speaking styles. A mismatch benefit was observed when combining Flat targets with the Exaggerated masker and Exaggerated targets with the Flat masker, and for both Flat and Exaggerated targets paired with the Normal masker. For children, there was a significant effect of age in all conditions. Flat targets in the Flat masker were associated with lower SRTs than the other two matched conditions, and a mismatch benefit was observed for young children only when the target f o contour was less variable than the masker f o contour. CONCLUSIONS: Whereas child-directed speech often has exaggerated pitch contours, young children were better able to recognize speech with less variable f o. Age effects were observed in the benefit of mismatched speaking styles for some conditions, which could be related to differences in baseline SRTs rather than differences in segregation abilities.


Asunto(s)
Percepción del Habla , Habla , Adulto , Adolescente , Humanos , Femenino , Preescolar , Niño , Adulto Joven , Enmascaramiento Perceptual , Lenguaje , Desarrollo Infantil
18.
Lang Speech Hear Serv Sch ; 54(4): 1195-1207, 2023 10 02.
Artículo en Inglés | MEDLINE | ID: mdl-37343547

RESUMEN

PURPOSE: The purpose of this project is to assess the acoustical conditions in which optimal intelligibility and low listening difficulty can be achieved in real classrooms for elementary students, taking into consideration the effects of dysphonic voice and typical classroom noise. METHOD: Speech intelligibility tests were performed in six elementary classrooms with 80 normal-hearing students aged 7-11 years. The speech material was produced by a female actor using a normal voice quality and simulating a dysphonic voice. The stimuli were played by a Head and Torso Simulator. Child babble noise and classrooms with different reverberation times were used to obtain a Speech Transmission Index (STI) range from 0.2 to 0.7, corresponding to the categories bad, poor, fair, and good. RESULTS: The results showed a statistically significant decrease in intelligibility when the speaker was dysphonic, in STI higher than 0.33. The rating of listening difficulty showed a significantly greater difficulty in perceiving the dysphonic voice. In addition, younger children showed poorer performance and greater listening difficulty compared with older children when listening to the normal voice quality. Both groups were equally impacted when the voice was dysphonic. CONCLUSIONS: The results suggested that better acoustic conditions are needed for children to reach a good level of intelligibility and to reduce listening difficulty if the teacher is suffering from voice problems. This was true for children regardless of grade level, highlighting the importance of ensuring more favorable acoustic conditions for children throughout all elementary schools. SUPPLEMENTAL MATERIAL: https://doi.org/10.23641/asha.23504487.


Asunto(s)
Percepción del Habla , Humanos , Femenino , Niño , Adolescente , Acústica , Ruido , Inteligibilidad del Habla , Estudiantes , Acústica del Lenguaje
19.
Hear Res ; 406: 108230, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33951577

RESUMEN

While the audible frequency range for humans spans approximately 20 Hz to 20 kHz, children display enhanced sensitivity relative to adults when detecting extended high frequencies (frequencies above 8 kHz; EHFs), as indicated by better pure tone thresholds. The impact that this increased hearing sensitivity to EHFs may have on children's speech recognition has not been established. One context in which EHF hearing may be particularly important for children is when recognizing speech in the presence of competing talkers. In the present study, we examined the extent to which school-age children (ages 5-17 years) with normal hearing were able to benefit from EHF cues when recognizing sentences in a two-talker speech masker. Two filtering conditions were tested: all stimuli were either full band or were low-pass filtered at 8 kHz to remove EHFs. Given that EHF energy emission in speech is highly dependent on head orientation of the talker (i.e., radiation becomes more directional with increasing frequency), two masker head angle conditions were tested: both co-located maskers were facing 45°, or both were facing 60° relative to the listener. The results demonstrated that regardless of age, children performed better when EHFs were present. In addition, a small change in masker head orientation also impacted performance, with better recognition at 60° compared to 45°. These findings suggest that EHF energy in the speech signal above 8 kHz is beneficial for children in complex listening situations. The magnitude of benefit from EHF cues and talker head orientation cues did not differ between children and adults. Therefore, while EHFs were beneficial for children as young as 5 years of age, children's generally better EHF hearing relative to adults did not provide any additional benefit.


Asunto(s)
Señales (Psicología) , Percepción del Habla , Habla , Adolescente , Niño , Preescolar , Audición , Humanos , Enmascaramiento Perceptual
20.
J Speech Lang Hear Res ; 64(1): 206-217, 2021 01 14.
Artículo en Inglés | MEDLINE | ID: mdl-33375828

RESUMEN

Purpose The purpose of this study was to examine the independent and combined contributions of fundamental frequency (F0) and vocal tract length (VTL) differences on children's speech-in-speech recognition in the presence of a competing two-talker masker. Method Participants were 64 children (5-17 years old) and 25 adults (18-39 years old). Sentence recognition thresholds were measured in a two-talker masker. Target sentences had either the same mean F0 and VTL of the masker or were digitally altered so that the target and masker differed in F0 (Experiment 1), differed in VTL (Experiment 2), or differed in both F0 and VTL (Experiment 3). To determine the benefit, masking release was computed by subtracting thresholds in each shifted condition from the threshold in the unshifted condition. Results Results demonstrate that children's ability to benefit from either F0 or VTL differences (Experiments 1 and 2) depended on listener age, with younger children showing less improvement in speech reception thresholds compared to older children and adults. Age effects were also evident in the combined-cue conditions (Experiment 3), but children showed greater improvements compared to F0-only or VTL-only manipulations. Conclusions There was a prolonged pattern of development in children's ability to benefit from F0 or VTL differences between target and masker speech. Young children failed to capitalize on F0 and VTL differences to the same extent as older children and adults but did show a robust benefit when the cues were combined, supporting the hypothesis that younger children rely more heavily on redundant cues compared to older children and adults.


Asunto(s)
Percepción del Habla , Voz , Adolescente , Adulto , Niño , Preescolar , Humanos , Enmascaramiento Perceptual , Reconocimiento en Psicología , Instituciones Académicas , Adulto Joven
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