RESUMO
Older listeners often report difficulties understanding speech in noisy environments. It is important to identify where in the auditory pathway hearing-in-noise deficits arise to develop appropriate therapies. We tested how encoding of sounds is affected by masking noise at early stages of the auditory pathway by recording responses of principal cells in the anteroventral cochlear nucleus (AVCN) of aging CBA/CaJ and C57BL/6J mice in vivo. Previous work indicated that masking noise shifts the dynamic range of single auditory nerve fibers (ANFs), leading to elevated tone thresholds. We hypothesized that such threshold shifts could contribute to increased hearing-in-noise deficits with age if susceptibility to masking increased in AVCN units. We tested this by recording the responses of AVCN principal neurons to tones in the presence and absence of masking noise. Surprisingly, we found that masker-induced threshold shifts decreased with age in primary-like units and did not change in choppers. In addition, spontaneous activity decreased in primary-like and chopper units of old mice, with no change in dynamic range or tuning precision. In C57 mice, which undergo early-onset hearing loss, units showed similar changes in threshold and spontaneous rate at younger ages, suggesting they were related to hearing loss and not simply aging. These findings suggest that sound information carried by AVCN principal cells remains largely unchanged with age. Therefore, hearing-in-noise deficits may result from other changes during aging, such as distorted across-channel input from the cochlea and changes in sound coding at later stages of the auditory pathway.
Assuntos
Envelhecimento , Núcleo Coclear , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Ruído , Animais , Núcleo Coclear/fisiologia , Envelhecimento/fisiologia , Masculino , Estimulação Acústica , Neurônios/fisiologia , Feminino , Limiar Auditivo/fisiologia , Mascaramento Perceptivo/fisiologia , Camundongos , Potenciais de Ação/fisiologiaRESUMO
PURPOSE: A corpus of English matrix sentences produced by 60 native and nonnative speakers of English was developed as part of a multinational coalition task group. This corpus was tested on a large cohort of U.S. Service members in order to examine the effects of talker nativeness, listener nativeness, masker type, and hearing sensitivity on speech recognition performance in this population. METHOD: A total of 1,939 U.S. Service members (ages 18-68 years) completed this closed-set listening task, including 430 women and 110 nonnative English speakers. Stimuli were produced by native and nonnative speakers of English and were presented in speech-shaped noise and multitalker babble. Keyword recognition accuracy and response times were analyzed. RESULTS: General(ized) linear mixed-effects regression models found that, on the whole, speech recognition performance was lower for listeners who identified as nonnative speakers of English and when listening to speech produced by nonnative speakers of English. Talker and listener effects were more pronounced when listening in a babble masker than in a speech-shaped noise masker. Response times varied as a function of recognition score, with longest response times found for intermediate levels of performance. CONCLUSIONS: This study found additive effects of talker and listener nonnativeness when listening to speech in background noise. These effects were present in both accuracy and response time measures. No multiplicative effects of talker and listener language background were found. There was little evidence of a negative interaction between talker nonnativeness and hearing impairment, suggesting that these factors may have redundant effects on speech recognition. SUPPLEMENTAL MATERIAL: https://doi.org/10.23641/asha.26060191.
Assuntos
Ruído , Mascaramento Perceptivo , Inteligibilidade da Fala , Percepção da Fala , Humanos , Feminino , Adulto , Pessoa de Meia-Idade , Masculino , Adulto Jovem , Idoso , Adolescente , Estados Unidos , Mascaramento Perceptivo/fisiologia , Estudos de Coortes , Idioma , MilitaresRESUMO
In prosopagnosia, brain lesions impair overt face recognition, but not face detection, and may coexist with residual covert recognition of familiar faces. Previous studies that simulated covert recognition in healthy individuals have impaired face detection as well as recognition, thus not fully mirroring the deficits in prosopagnosia. We evaluated a model of covert recognition based on continuous flash suppression (CFS). Familiar and unfamiliar faces and houses were masked while participants performed two discrimination tasks. With increased suppression, face/house discrimination remained largely intact, but face familiarity discrimination deteriorated. Covert recognition was present across all masking levels, evinced by higher pupil dilation to familiar than unfamiliar faces. Pupil dilation was uncorrelated with overt performance across subjects. Thus, CFS can impede overt face recognition without disrupting covert recognition and face detection, mirroring critical features of prosopagnosia. CFS could be used to uncover shared neural mechanisms of covert recognition in prosopagnosic patients and neurotypicals.
Assuntos
Reconhecimento Facial , Pupila , Reconhecimento Psicológico , Humanos , Reconhecimento Facial/fisiologia , Adulto , Feminino , Masculino , Reconhecimento Psicológico/fisiologia , Adulto Jovem , Pupila/fisiologia , Mascaramento Perceptivo/fisiologiaRESUMO
Humans can estimate the number of visually presented items without counting. In most studies on numerosity perception, items are uniformly distributed across displays, with identical distributions in central and eccentric parts. However, the neural and perceptual representation of the human visual field differs between the fovea and the periphery. For example, in peripheral vision, there are strong asymmetries with regard to perceptual interferences between visual items. In particular, items arranged radially usually interfere more strongly with each other than items arranged tangentially (the radial-tangential anisotropy). This has been shown for crowding (the deleterious effect of clutter on target identification) and redundancy masking (the reduction of the number of perceived items in repeating patterns). In the present study, we tested how the radial-tangential anisotropy of peripheral vision impacts numerosity perception. In four experiments, we presented displays with varying numbers of discs that were predominantly arranged radially or tangentially, forming strong and weak interference conditions, respectively. Participants were asked to report the number of discs. We found that radial displays were reported as less numerous than tangential displays for all radial and tangential manipulations: weak (Experiment 1), strong (Experiment 2), and when using displays with mixed contrast polarity discs (Experiments 3 and 4). We propose that numerosity perception exhibits a significant radial-tangential anisotropy, resulting from local spatial interactions between items.
Assuntos
Reconhecimento Visual de Modelos , Humanos , Anisotropia , Adulto , Masculino , Feminino , Adulto Jovem , Reconhecimento Visual de Modelos/fisiologia , Estimulação Luminosa/métodos , Campos Visuais/fisiologia , Mascaramento Perceptivo/fisiologia , Percepção Visual/fisiologiaRESUMO
Since its creation, the coordinate response measure (CRM) corpus has been applied in hundreds of studies to explore the mechanisms of informational masking in multi-talker situations, but also in speech-in-noise or auditory attentional tasks. Here, we present its French version, with equivalent content to the original version in English. Furthermore, an evaluation of speech-on-speech intelligibility in French shows informational masking with similar result patterns to the original data in English. This validation of the French CRM corpus allows to propose the use of the CRM for intelligibility tests in French, and for comparisons with a foreign language under masking conditions.
Assuntos
Idioma , Inteligibilidade da Fala , Percepção da Fala , Humanos , Percepção da Fala/fisiologia , Feminino , Masculino , Adulto , Mascaramento Perceptivo/fisiologia , França , Adulto Jovem , RuídoRESUMO
Multilingual speakers can find speech recognition in everyday environments like restaurants and open-plan offices particularly challenging. In a world where speaking multiple languages is increasingly common, effective clinical and educational interventions will require a better understanding of how factors like multilingual contexts and listeners' language proficiency interact with adverse listening environments. For example, word and phrase recognition is facilitated when competing voices speak different languages. Is this due to a "release from masking" from lower-level acoustic differences between languages and talkers, or higher-level cognitive and linguistic factors? To address this question, we created a "one-man bilingual cocktail party" selective attention task using English and Mandarin speech from one bilingual talker to reduce low-level acoustic cues. In Experiment 1, 58 listeners more accurately recognized English targets when distracting speech was Mandarin compared to English. Bilingual Mandarin-English listeners experienced significantly more interference and intrusions from the Mandarin distractor than did English listeners, exacerbated by challenging target-to-masker ratios. In Experiment 2, 29 Mandarin-English bilingual listeners exhibited linguistic release from masking in both languages. Bilinguals experienced greater release from masking when attending to English, confirming an influence of linguistic knowledge on the "cocktail party" paradigm that is separate from primarily energetic masking effects. Effects of higher-order language processing and expertise emerge only in the most demanding target-to-masker contexts. The "one-man bilingual cocktail party" establishes a useful tool for future investigations and characterization of communication challenges in the large and growing worldwide community of Mandarin-English bilinguals.
Assuntos
Atenção , Multilinguismo , Percepção da Fala , Humanos , Percepção da Fala/fisiologia , Adulto , Feminino , Masculino , Adulto Jovem , Atenção/fisiologia , Mascaramento Perceptivo/fisiologia , PsicolinguísticaRESUMO
Previous research has demonstrated cognate translation priming effects in masked priming lexical decision tasks (LDTs) even when a bilingual's two languages have different scripts. Because those effect sizes are normally larger than with noncognates, the effects have been partially attributed to the impact of prime-target phonological similarity. The present research extended that work by examining priming effects when using triple different-script cognates, i.e., /ka1 feɪ1/-coffee-ã³ã¼ãã¼/KoRhiR/. Specifically, masked cognate priming effects were examined in six different priming directions (i.e., L1âL2, L1âL3, and L2âL3) for Chinese-English-Japanese trilinguals using LDTs. Significant priming effects were observed only when the primes were from the stronger language. This asymmetric pattern suggests that the phonological similarity of cognate primes only facilitates the processing of different-script triple cognates to the extent that the processing of the prime is robust enough to make phonology available before target processing is finished.
Assuntos
Multilinguismo , Humanos , Adulto , Adulto Jovem , Tomada de Decisões , Masculino , Feminino , Psicolinguística , Idioma , Mascaramento Perceptivo/fisiologia , Fonética , População do Leste AsiáticoRESUMO
PURPOSE: This study aimed to investigate challenges in speech-in-noise (SiN) processing faced by school-age children with autism spectrum conditions (ASCs) and their impact on listening effort. METHOD: Participants, including 23 Mandarin-speaking children with ASCs and 19 age-matched neurotypical (NT) peers, underwent sentence recognition tests in both quiet and noisy conditions, with a speech-shaped steady-state noise masker presented at 0-dB signal-to-noise ratio in the noisy condition. Recognition accuracy rates and task-evoked pupil responses were compared to assess behavioral performance and listening effort during auditory tasks. RESULTS: No main effect of group was found on accuracy rates. Instead, significant effects emerged for autistic trait scores, listening conditions, and their interaction, indicating that higher trait scores were associated with poorer performance in noise. Pupillometric data revealed significantly larger and earlier peak dilations, along with more varied pupillary dynamics in the ASC group relative to the NT group, especially under noisy conditions. Importantly, the ASC group's peak dilation in quiet mirrored that of the NT group in noise. However, the ASC group consistently exhibited reduced mean dilations than the NT group. CONCLUSIONS: Pupillary responses suggest a different resource allocation pattern in ASCs: An initial sharper and larger dilation may signal an intense, narrowed resource allocation, likely linked to heightened arousal, engagement, and cognitive load, whereas a subsequent faster tail-off may indicate a greater decrease in resource availability and engagement, or a quicker release of arousal and cognitive load. The presence of noise further accentuates this pattern. This highlights the unique SiN processing challenges children with ASCs may face, underscoring the importance of a nuanced, individual-centric approach for interventions and support.
Assuntos
Transtorno do Espectro Autista , Ruído , Pupila , Percepção da Fala , Humanos , Masculino , Percepção da Fala/fisiologia , Criança , Pupila/fisiologia , Feminino , Transtorno do Espectro Autista/psicologia , Transtorno do Espectro Autista/fisiopatologia , Mascaramento Perceptivo/fisiologiaRESUMO
Four experiments were conducted to gain a better understanding of the visual mechanisms related to how integration of partial shape cues provides for recognition of the full shape. In each experiment, letters formed as outline contours were displayed as a sequence of adjacent segments (fragments), each visible during a 17-ms time frame. The first experiment varied the contrast of the fragments. There were substantial individual differences in contrast sensitivity, so stimulus displays in the masking experiments that followed were calibrated to the sensitivity of each participant. Masks were displayed either as patterns that filled the entire screen (full field) or as successive strips that were sliced from the pattern, each strip lying across the location of the letter fragment that had been shown a moment before. Contrast of masks were varied to be lighter or darker than the letter fragments. Full-field masks, whether light or dark, provided relatively little impairment of recognition, as was the case for mask strips that were lighter than the letter fragments. However, dark strip masks proved to be very effective, with the degree of recognition impairment becoming larger as mask contrast was increased. A final experiment found the strip masks to be most effective when they overlapped the location where the letter fragments had been shown a moment before. They became progressively less effective with increased spatial separation from that location. Results are discussed with extensive reference to potential brain mechanisms for integrating shape cues.
Assuntos
Sensibilidades de Contraste , Percepção de Forma , Reconhecimento Visual de Modelos , Mascaramento Perceptivo , Estimulação Luminosa , Humanos , Mascaramento Perceptivo/fisiologia , Sensibilidades de Contraste/fisiologia , Estimulação Luminosa/métodos , Adulto , Reconhecimento Visual de Modelos/fisiologia , Percepção de Forma/fisiologia , Masculino , Feminino , Sinais (Psicologia) , Adulto JovemRESUMO
Age-related changes in auditory processing may reduce physiological coding of acoustic cues, contributing to older adults' difficulty perceiving speech in background noise. This study investigated whether older adults differed from young adults in patterns of acoustic cue weighting for categorizing vowels in quiet and in noise. All participants relied primarily on spectral quality to categorize /É/ and /æ/ sounds under both listening conditions. However, relative to young adults, older adults exhibited greater reliance on duration and less reliance on spectral quality. These results suggest that aging alters patterns of perceptual cue weights that may influence speech recognition abilities.
Assuntos
Sinais (Psicologia) , Mascaramento Perceptivo , Percepção da Fala , Humanos , Percepção da Fala/fisiologia , Idoso , Adulto Jovem , Feminino , Masculino , Adulto , Mascaramento Perceptivo/fisiologia , Ruído/efeitos adversos , Envelhecimento/fisiologia , Envelhecimento/psicologia , Acústica da Fala , Pessoa de Meia-Idade , Fonética , Fatores Etários , AdolescenteRESUMO
The visual system often undergoes a relatively stable perception even in a noisy visual environment. This crucial function was reflected in a visual perception phenomenon-serial dependence, in which recent stimulus history systematically biases current visual decisions. Although serial dependence effects have been revealed in numerous studies, few studies examined whether serial dependence would require visual awareness. By using the continuous flash suppression (CFS) technique to render grating stimuli invisible, we investigated whether serial dependence effects could emerge at the unconscious levels. In an orientation adjustment task, subjects viewed a randomly oriented grating and reported their orientation perception via an adjustment response. Subjects performed a series of three type trial pairs. The first two trial pairs, in which subjects were instructed to make a response or no response toward the first trial of the pairs, respectively, were used to measure serial dependence at the conscious levels; the third trial pair, in which the grating stimulus in the first trial of the pair was masked by a CFS stimulus, was used to measure the serial dependence at the unconscious levels. One-back serial dependence effects for the second trial of the pairs were evaluated. We found significant serial dependence effects at the conscious levels, whether absence (Experiment 1) or presence (Experiment 2) of CFS stimuli, but failed to find the effects at the unconscious levels, corroborating the view that serial dependence requires visual awareness.
Assuntos
Conscientização , Estimulação Luminosa , Percepção Visual , Humanos , Conscientização/fisiologia , Estimulação Luminosa/métodos , Masculino , Percepção Visual/fisiologia , Adulto Jovem , Feminino , Adulto , Mascaramento Perceptivo/fisiologia , Orientação/fisiologiaRESUMO
Crowding and the word superiority effect are two perceptual phenomena that influence reading. The identification of the inner letters of a word can be hindered by crowding from adjacent letters, but it can be facilitated by the word context itself (the word superiority effect). In the present study, strings of four-letters (words and non-words) with different inter-letter spacings (ranging from an optimal spacing to produce crowding to a spacing too large to produce crowding) were presented briefly in the periphery and participants were asked to identify the third letter of the string. Each word had a partner word that was identical except for its third letter (e.g., COLD, CORD) so that guessing as the source of the improved performance for words could be ruled out. Unsurprisingly, letter identification accuracy for words was better than non-words. For non-words, it was lowest at closer spacings, confirming crowding. However, for words, accuracy remained high at all inter-letter spacings showing that crowding did not prevent identification of the inner letters. This result supports models of "holistic" word recognition where partial cues can lead to recognition without first identifying individual letters. Once the word is recognized, its inner letters can be recovered, despite their feature loss produced by crowding.
Assuntos
Reconhecimento Visual de Modelos , Leitura , Humanos , Reconhecimento Visual de Modelos/fisiologia , Estimulação Luminosa/métodos , Adulto Jovem , Adulto , Feminino , Masculino , Análise de Variância , Sinais (Psicologia) , Mascaramento Perceptivo/fisiologia , Reconhecimento Psicológico/fisiologiaRESUMO
Urban expansion has increased pollution, including both physical (e.g., exhaust, litter) and sensory (e.g., anthropogenic noise) components. Urban avian species tend to increase the frequency and/or amplitude of songs to reduce masking by low-frequency noise. Nevertheless, song propagation to the receiver can also be constrained by the environment. We know relatively little about how this propagation may be altered across species that (1) vary in song complexity and (2) inhabit areas along an urbanization gradient. We investigated differences in song amplitude, attenuation, and active space, or the maximum distance a receiver can detect a signal, in two human-commensal species: the house sparrow (Passer domesticus) and house finch (Haemorhous mexicanus). We described urbanization both discretely and quantitatively to investigate the habitat characteristics most responsible for propagation changes. We found mixed support for our hypothesis of urban-specific degradation of songs. Urban songs propagated with higher amplitude; however, urban song fidelity was species-specific and showed lowered active space for urban house finch songs. Taken together, our results suggest that urban environments may constrain the propagation of vocal signals in species-specific manners. Ultimately, this has implications for the ability of urban birds to communicate with potential mates or kin.
Assuntos
Tentilhões , Especificidade da Espécie , Urbanização , Vocalização Animal , Animais , Vocalização Animal/fisiologia , Tentilhões/fisiologia , Pardais/fisiologia , Ruído , Espectrografia do Som , Ecossistema , Humanos , Mascaramento Perceptivo/fisiologia , MasculinoRESUMO
The context-based Extended Speech Transmission Index (cESTI) (van Schoonhoven et al., 2022, J. Acoust. Soc. Am. 151, 1404-1415) was successfully applied to predict the intelligibility of monosyllabic words with different degrees of context in interrupted noise. The current study aimed to use the same model for the prediction of sentence intelligibility in different types of non-stationary noise. The necessary context factors and transfer functions were based on values found in existing literature. The cESTI performed similar to or better than the original ESTI when noise had speech-like characteristics. We hypothesize that the remaining inaccuracies in model predictions can be attributed to the limits of the modelling approach with regard to mechanisms, such as modulation masking and informational masking.
Assuntos
Ruído , Mascaramento Perceptivo , Inteligibilidade da Fala , Percepção da Fala , Humanos , Mascaramento Perceptivo/fisiologia , Feminino , Percepção da Fala/fisiologia , Masculino , Adulto , Adulto Jovem , Acústica da Fala , Modelos Teóricos , Estimulação AcústicaRESUMO
To what degree human cognition is influenced by subliminal stimuli is a controversial empirical question. One striking example was reported by Linser and Goschke (2007): participants overestimated how much control they had over objectively uncontrollable stimuli when masked congruent primes were presented immediately before the action. Critically, however, unawareness of the masked primes was established by post hoc data selection. In our preregistered study we sought to explore these findings while adjusting prime visibility based on individual thresholds, so that each participant underwent both visible and non-visible conditions. In experiment 1, N = 39 participants engaged in a control judgement task: following the presentation of a semantic prime, they freely selected between two keys, which triggered the appearance of a colored circle. The color of the circles, however, was independent of the key-press. Subsequently, participants assessed their perceived control over the circle's color, based on their key-presses, via a rating scale that ranged from 0 % (no control) to 100 % (complete control). Contrary to Linser and Goschke (2007)'s findings, this experiment demonstrated that predictive information influenced the experience of agency only when primes were consciously processed. In experiment 2, utilizing symbolic (arrow) primes, N = 35 participants had to rate their feeling of control over the effect-stimulus' identity during a two-choice identification paradigm (i.e., they were instructed to press a key corresponding to a target stimulus; with a contingency between target and effect stimulus of 75 %/25 %). The results revealed no significant influence of subliminal priming on agency perceptions. In summary, this study implies that unconscious stimuli may not exert a substantial influence on the conscious experience of agency, underscoring the need for careful consideration of methodological aspects and experimental design's impact on observed phenomena.
Assuntos
Inconsciente Psicológico , Humanos , Feminino , Masculino , Adulto , Adulto Jovem , Estimulação Subliminar , Mascaramento Perceptivo/fisiologia , Priming de Repetição/fisiologia , Ilusões/fisiologia , Desempenho Psicomotor/fisiologia , Adolescente , Conscientização/fisiologiaRESUMO
The assessment of mental effort is increasingly relevant in neurocognitive and life span domains. Pupillometry, the measure of the pupil size, is often used to assess effort but has disadvantages. Analysis of eye movements may provide an alternative, but research has been limited to easy and difficult task demands in younger adults. An effort measure must be sensitive to the whole effort profile, including "giving up" effort investment, and capture effort in different age groups. The current study comprised three experiments in which younger (n = 66) and older (n = 44) adults listened to speech masked by background babble at different signal-to-noise ratios associated with easy, difficult, and impossible speech comprehension. We expected individuals to invest little effort for easy and impossible speech (giving up) but to exert effort for difficult speech. Indeed, pupil size was largest for difficult but lower for easy and impossible speech. In contrast, gaze dispersion decreased with increasing speech masking in both age groups. Critically, gaze dispersion during difficult speech returned to levels similar to easy speech after sentence offset, when acoustic stimulation was similar across conditions, whereas gaze dispersion during impossible speech continued to be reduced. These findings show that a reduction in eye movements is not a byproduct of acoustic factors, but instead suggest that neurocognitive processes, different from arousal-related systems regulating the pupil size, drive reduced eye movements during high task demands. The current data thus show that effort in one sensory domain (audition) differentially impacts distinct functional properties in another sensory domain (vision).
Assuntos
Envelhecimento , Movimentos Oculares , Pupila , Percepção da Fala , Humanos , Pupila/fisiologia , Masculino , Feminino , Adulto Jovem , Idoso , Adulto , Percepção da Fala/fisiologia , Envelhecimento/fisiologia , Movimentos Oculares/fisiologia , Pessoa de Meia-Idade , Mascaramento Perceptivo/fisiologia , Estimulação AcústicaRESUMO
Recent studies suggest that binocular adding S+ and differencing S- channels play an important role in binocular vision. To test for such a role in the context of binocular contrast detection and binocular summation, we employed a surround masking paradigm consisting of a central target disk surrounded by a mask annulus. All stimuli were horizontally oriented 0.5c/d sinusoidal gratings. Correlated stimuli were identical in interocular spatial phase while anticorrelated stimuli were opposite in interocular spatial phase. There were four target conditions: monocular left eye, monocular right eye, binocular correlated and binocular anticorrelated, and three surround mask conditions: no surround, binocularly correlated and binocularly anticorrelated. We observed consistent elevation of detection thresholds for monocular and binocular targets across the two binocular surround mask conditions. In addition, we found an interaction between the type of surround and the type of binocular target: both detection and summation were relatively enhanced by surround masks and targets with opposite interocular phase relationships and reduced by surround masks and targets with the same interocular phase relationships. The data were reasonably well accounted for by a model of binocular combination termed MAX (S+S-), in which the decision variable is the probability summation of modeled S+ and S- channel responses, with a free parameter determining the relative gains of the two channels. Our results support the existence of two channels involved in binocular combination, S+ and S-, whose relative gains are adjustable by surround context.
Assuntos
Sensibilidades de Contraste , Mascaramento Perceptivo , Estimulação Luminosa , Limiar Sensorial , Visão Binocular , Humanos , Visão Binocular/fisiologia , Mascaramento Perceptivo/fisiologia , Sensibilidades de Contraste/fisiologia , Limiar Sensorial/fisiologia , Estimulação Luminosa/métodos , Psicofísica , Visão Monocular/fisiologia , AdultoRESUMO
OBJECTIVES: The objectives of the present study were to investigate the effects of age-related changes in extended high-frequency (EHF) hearing, peripheral neural function, working memory, and executive function on speech perception deficits in middle-aged individuals with clinically normal hearing. DESIGN: We administered a comprehensive assessment battery to 37 participants spanning the age range of 20 to 56 years. This battery encompassed various evaluations, including standard and EHF pure-tone audiometry, ranging from 0.25 to 16 kHz. In addition, we conducted auditory brainstem response assessments with varying stimulation rates and levels, a spatial release from masking (SRM) task, and cognitive evaluations that involved the Trail Making test (TMT) for assessing executive function and the Abbreviated Reading Span test (ARST) for measuring working memory. RESULTS: The results indicated a decline in hearing sensitivities at EHFs and an increase in completion times for the TMT with age. In addition, as age increased, there was a corresponding decrease in the amount of SRM. The declines in SRM were associated with age-related declines in hearing sensitivity at EHFs and TMT performance. While we observed an age-related decline in wave I responses, this decline was primarily driven by age-related reductions in EHF thresholds. In addition, the results obtained using the ARST did not show an age-related decline. Neither the auditory brainstem response results nor ARST scores were correlated with the amount of SRM. CONCLUSIONS: These findings suggest that speech perception deficits in middle age are primarily linked to declines in EHF hearing and executive function, rather than cochlear synaptopathy or working memory.
Assuntos
Audiometria de Tons Puros , Potenciais Evocados Auditivos do Tronco Encefálico , Função Executiva , Memória de Curto Prazo , Percepção da Fala , Humanos , Pessoa de Meia-Idade , Adulto , Masculino , Percepção da Fala/fisiologia , Feminino , Memória de Curto Prazo/fisiologia , Adulto Jovem , Potenciais Evocados Auditivos do Tronco Encefálico/fisiologia , Função Executiva/fisiologia , Cognição/fisiologia , Envelhecimento/fisiologia , Mascaramento Perceptivo/fisiologia , Teste de Sequência AlfanuméricaRESUMO
This study investigates the effect of spatial release from masking (SRM) in bilateral bone conduction (BC) stimulation at the mastoid. Nine adults with normal hearing were tested to determine SRM based on speech recognition thresholds (SRTs) in simulated spatial configurations ranging from 0 to 180 degrees. These configurations were based on nonindividualized head-related transfer functions. The participants were subjected to sound stimulation through either air conduction (AC) via headphones or BC. The results indicated that both the angular separation between the target and the masker, and the modality of sound stimulation, significantly influenced speech recognition performance. As the angular separation between the target and the masker increased up to 150°, both BC and AC SRTs decreased, indicating improved performance. However, performance slightly deteriorated when the angular separation exceeded 150°. For spatial separations less than 75°, BC stimulation provided greater spatial benefits than AC, although this difference was not statistically significant. For separations greater than 75°, AC stimulation offered significantly more spatial benefits than BC. When speech and noise originated from the same side of the head, the "better ear effect" did not significantly contribute to SRM. However, when speech and noise were located on opposite sides of the head, this effect became dominant in SRM.
Assuntos
Condução Óssea , Percepção da Fala , Adulto , Humanos , Processo Mastoide , Mascaramento Perceptivo/fisiologia , Percepção da Fala/fisiologia , AudiçãoRESUMO
Auditory detection of the Amplitude Modulation (AM) of sounds, crucial for speech perception, improves until 10 years of age. This protracted development may not only be explained by sensory maturation, but also by improvements in processing efficiency: the ability to make efficient use of available sensory information. This hypothesis was tested behaviorally on 86 6-to-9-year-olds and 15 adults using AM-detection tasks assessing absolute sensitivity, masking, and response consistency in the AM domain. Absolute sensitivity was estimated by the detection thresholds of a sinusoidal AM applied to a pure-tone carrier; AM masking was estimated as the elevation of AM-detection thresholds produced when replacing the pure-tone carrier by a narrowband noise; response consistency was estimated using a double-pass paradigm where the same set of stimuli was presented twice. Results showed that AM sensitivity improved from childhood to adulthood, but did not change between 6 and 9 years. AM masking did not change with age, suggesting that the selectivity of perceptual AM filters was adult-like by 6 years. However, response consistency increased developmentally, supporting the hypothesis of reduced processing efficiency in early childhood. At the group level, double-pass data of children and adults were well simulated by a model of the human auditory system assuming a higher level of internal noise for children. At the individual level, for both children and adults, double-pass data were better simulated when assuming a sub-optimal decision strategy in addition to differences in internal noise. In conclusion, processing efficiency for AM detection is reduced in childhood. Moreover, worse AM detection was linked to both systematic and stochastic inefficiencies, in both children and adults.