No / The relative timing of auditory and visual stimuli is a critical cue for determining whether sensory signals relate to a common source and for making inferences about causality. However, the way in which the brain represents temporal relationships remains poorly understood. Recent studies indicate that our perception of multisensory timing is flexible--adaptation to a regular inter-modal delay alters the point at which subsequent stimuli are judged to be simultaneous. Here, we measure the effect of audio-visual asynchrony adaptation on the perception of a wide range of sub-second temporal relationships. We find distinctive patterns of induced biases that are inconsistent with the previous explanations based on changes in perceptual latency. Instead, our results can be well accounted for by a neural population coding model in which: (i) relative audio-visual timing is represented by the distributed activity across a relatively small number of neurons tuned to different delays; (ii) the algorithm for reading out this population code is efficient, but subject to biases owing to under-sampling; and (iii) the effect of adaptation is to modify neuronal response gain. These results suggest that multisensory timing information is represented by a dedicated population code and that shifts in perceived simultaneity following asynchrony adaptation arise from analogous neural processes to well-known perceptual after-effects.

Auditory sensitivity was associated with speech perception which influenced Chinese word reading mainly through morphological awareness and rapid automatized naming. In contrast, for English word reading, the best model required an additional direct path from suprasegmental sensitivity (in Chinese) to English word reading on the basis of the proposed model. To be specific, auditory sensitivity was fully mediated by segmental and suprasegmental speech perception which further impacted English word reading mainly through phonological awareness; in addition, suprasegmental perception or speech prosody (in Chinese) was directly associated with word reading. Third, stress sensitivity in English was highly associated with speech prosodic sensitivity in Chinese. Hierarchical regressions also showed that suprasegmental speech perception failed to account unique variance for English word reading beyond phonological awareness when stress sensitivity was further controlled, suggesting that Chinese suprasegmental speech sensitivity may influence English word reading at least partly through its overlap with stress sensitivity. / This study investigated the associations of auditory sensitivity, speech perception, Chinese reading as a first language (L1) and English reading as a second language (L2) in Hong Kong Chinese children. Participants were 180 second and third graders (98 boys and 82 girls, mean age=98.6months). Apart from auditory sensitivity (both temporal and rhythmic processing measures), English stress sensitivity and English word reading, children were also tested on Chinese tasks of speech perception (both segmental and suprasegmental tasks), phonological awareness, rapid automatized naming (digit), verbal short-term memory, morphological awareness and Chinese word reading. I proposed a four-stage model, in which auditory sensitivity is fully mediated by speech perception at both the segmental and suprasegmental levels. These further impact word reading through phonological awareness, rapid automatized naming, verbal short-term memory and morphological awareness. A series of nested model comparisons were conducted to test this model for both Chinese and English word reading using structural equation modeling. For Chinese word reading, the proposed four-stage model was demonstrated to be the best model. / Zhang, Juan. / Advisers: Catherine A. McBride-Chang; Him Cheung. / Source: Dissertation Abstracts International, Volume: 73-06, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2011. / Includes bibliographical references (leaves 103-118). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [201-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.

Doctorat en sciences psychologiques / info:eu-repo/semantics/nonPublished

published_or_final_version / Speech and Hearing Sciences / Master / Master of Science in Audiology

This study examined the relationship between selective serotonin reuptake inhibitor (SSRI) medication and auditory measures in clinically depressed women. Experimental subjects were tested in both a medicated and unmedicated condition. Experimental subjects were compared to a normal control group; additionally intrasubject comparison was made within the experimental group. Test measures included: audiometry, tympanometry, otoacoustic emissions, uncomfortable loudness level, masking level difference, SCAN-A, Synthetic Sentence Identification (SSI), and the low predictability section of the Revised Speech in noise (RSPIN). The unmedicated group scored significantly less favorably than the control group on the following tests; SCAN-A (composite, filtered words, and auditory figure ground), R-SPIN (0MCR condition in both the right and left ears). Additionally, the unmedicated group scored significantly less favorably than the medicated group on the SSI (-20MCR condition right ear only) and of the R-SPIN (0MCR condition right ear only). Other test measures indicated consistent trends but did reach significance.

Five humans were exposed to a matching to sample task in which the delay (range = 0 to 32 seconds) between sample stimulus offset and comparison onset was manipulated across conditions. Auditory stimuli (1” tone) and arbitrary symbols served as sample stimuli for three (S1, S2, S3) and two (S4 and S5) subjects, respectively. Uppercase English letters (S, M, and N) served as comparison stimuli for all subjects. Results show small but systematic effects of the retention interval on accuracy and latency to selection of comparison stimuli. The results fail to show a difference between subjects exposed to auditory and visual sample stimuli. Some reasons for the failure to note a difference are discussed.

The intent of this project is to develop an auditory training program for kindergarten children which will strengthen auditory perception. The program will identify the essential auditory skills, establish objectives, construct evaluative measures and outline activities that will develop basic auditory perception skills.

A perda auditiva unilateral (PAUn) é caracterizada pela diminuição da audição em apenas uma orelha. Indivíduos com este tipo de perda auditiva podem apresentar comprometimento nas habilidades auditivas de localização sonora, processamento temporal, ordenação e resolução temporal. O objetivo deste estudo foi verificar as habilidades auditivas de ordenação temporal, resolução temporal e localização sonora, antes e após a adaptação do aparelho de amplificação sonora individual (AASI). Foram avaliados 22 indivíduos, com idades entre 18 e 60 anos, com diagnóstico de PAUn sensorioneural ou mista, de graus leve a severo. O estudo foi dividido em duas etapas: a pré e a pós-adaptação de AASI. Em ambas as etapas, os indivíduos foram submetidos a uma anamnese, aplicação do Questionário de Habilidade Auditiva da Localização da fonte sonora, avaliação simplificada do processamento auditivo (ASPA) e Random Gap Detection Test (RGDT). O presente estudo encontrou diferença estatisticamente significante na avaliação da ASPA, exceto no teste de memória para sons não verbais em sequência (TMSnV), no RGDT e no Questionário de Habilidade Auditiva da Localização Sonora. A conclusão do estudo foi que com o uso efetivo do AASI, indivíduos com PAUn apresentaram melhora nas habilidades auditivas de localização sonora, ordenação e resolução temporal. / The Unilateral hearing loss (UHL) is characterized by decreased hearing in one ear. In individuals with this type of hearing loss the hearing abilities of sound localization, and temporal processing, ordering and temporal resolution, are affected. The objective of this study was to assess the hearing abilities of temporal ordering, temporal resolution and sound localization before and after the fitting of a hearing aid (HA). They evaluated 22 subjects, aged 18 to 60 years, diagnosed with sensorineural or mixed UHL, from mild to severe degrees. The study was divided into two stages: the pre and post-adaptation of HA. In both phases, subjects were submitted to an interview, application of Questionnarie for Desabilities Associated with Impaired Auditory Localization, auditory processing screening protocol (APSP) and Random Gap Detection Test (RGDT). This study found no statistically significant difference in the evaluation of APSP except in the memory test for non-verbal sounds in sequence, in RGDT and Questionnarie for Desabilities Associated with Impaired Auditory Localization. The conclusion was that with the effective use of hearing aids, individuals with UHL showed improvement in the auditory abilities of sound localization, ordering and temporal resolution.

Vários aspectos do relacionamento entre mamíferos, como pareamento sexual e relações de grupo, requerem o reconhecimento de indivíduos. Sinais químicos são fundamentais nesse contexto, pois permitem a identificação individual e sexual. Roedores são animais que apresentam um senso olfatório muito desenvolvido e o empregam em sua comunicação social. Neste trabalho foi investigada a espécie de rato-de-espinho Trinomys yonenagae, conhecido como rabo-de-facho. T. yonenagae habita o semiárido, é colonial e fossorial. É uma das espécies mais conhecidas entre os equimídeos e um elemento-chave na Área de Preservação das Dunas e Veredas do Médio São Francisco, na Caatinga. Um paradigma habituação-discriminação foi usado para investigar a capacidade de T. yonenagae discriminar odores vindos da urina de conspecíficos desconhecidos. Foram usados: a) machos como sujeitos (n = 8) e fêmeas como doadoras (n = 2); b) fêmeas como sujeitos (n = 8) e machos como doadores (n = 2); c) machos como sujeitos (n = 8) e fêmeas como doadoras do pool de urina (n = 8); d) fêmeas como sujeitos (n = 8) e machos como doadores do pool de urina (n = 8). A duração de cada sessão dos testes foi de 10min. Durante três dias consecutivos o mesmo sujeito foi exposto ao odor A de um único doador. No quarto dia (teste de discriminação), o sujeito foi exposto simultaneamente ao odor A e ao odor de um novo doador (B), e o tempo de investigação de A e B foi medido. Não houve diferença significativa para as fêmeas, tanto na habituação [Anova, F=0,82; p=0,454] quanto na discriminação [teste t de Student [t7=1,078; sig. (2-tailed)=0,317] quando o odor era individual. Porém, houve diferença estatisticamente significante [F=3,67; p=0,043] tanto na habituação, como na discriminação [t7 = 3,605; sig. (2-tailed)=0,009] quando as fêmeas investigaram o odor vindo de um pool de urina. Entre os machos, tanto no grupo de doadores individuais quanto no grupo do pool de urina houve diminuição significativa [F=6,866; p=0,005] e [F=7,42; p=0,004 (pool)] no tempo em que os animais investigavam o odor A, da primeira para a segunda e terceira habituação. Na discriminação, também houve diferença significativa [t7=4,466; sig. (2-tailed)=0,003] e [t7=3,629; sig. (2-tailed)=0,008 (pool)] sendo o odor B mais investigado do que o odor A. Os resultados indicam que Trinomys yonenagae pode discriminar odores de coespecíficos e que há diferenças entre machos e fêmeas. Essa capacidade é significativa para um roedor de pequeno porte, de vida colonial, fossorial e de baixo metabolismo / Many aspects of mammalian social relationships, such as sexual pair bonds and group relationships, require individual recognition. Chemical cues are essential in this context, because they allow individual and sexual identification. In this work, olfactory communication in the spiny rat Trinomys yonenagae, known as rabo-de-facho, was investigated. This species is colonial, fossorial and is endemic to sand dunes fields at the Área de Preservação das Dunas e Veredas do Médio São Francisco, in the arid Brazilian Caatinga. A habituation-discrimination paradigm was used in order to investigate if T. yonenagae is capable to discriminate scents from unknown conspecifics urine. The following groups were investigated: a) males as subjects (n = 8) and females as donors (n = 2); b) females as subjects (n = 8) and males as donors (n = 2); c) males as subjects (n = 8) and females as urine pool donors (n = 8); d) females as subjects (n = 8) and males as urine pool donors (n = 8). The period of each test session was 10 min. During three consecutives days the same subject was exposed to the odor of a single donor (A). At fourth day (discrimination test), the subject was exposed simultaneously to odor A and the odor of a new donor (B), and the investigation time of A and B was measured. There wasnt significant difference for females both during the habituation [Anova, F=0,82; p=0,454] and discrimination [Student t test t7=1,078; sig.(2-tailed)=0,317] tests, when the source of odor was individual. However, there were statistical differences [F=3,67; p=0,043] both at habituation and at discrimination [t7 = 3,605; sig.(2-tailed)=0,009] tests, when females investigated the odor from the urine pool. For males, both individual urine scent and urine pool tests showed significant decrease [F=6,866; p=0,005 and F=7,42; p=0,004, respectively] of the time that males spent investigating odor A, from first to second and third habituation tests. At the discrimination test, in both groups odor B was significantly more investigated than odor A [t7=4,466; sig.(2-tailed)=0,003] and [t7=3,629; sig. (2-tailed)=0,008 (pool)]. The results indicate that Trinomys yonenagae is capable of discriminating odors from conspecifics, but in this context the behavior of males and females differs. This olfactory competence is compatible with the life-style, the habitat and the low metabolic rate found in T. yonenagae

A habilidade auditiva de resolução temporal consiste no tempo mínimo requerido para segregar ou resolver eventos acústicos. Esta habilidade é fundamental para a compreensão da fala humana, constituindo-se num pré-requisito para as habilidades lingüísticas, bem como para a leitura. Em 2003, Musiek desenvolveu um teste para avaliar os limiares de detecção de gap a ser utilizado na prática clínica - o GIN - Gap In Noise (Musiek et al., 2004). Para que o teste GIN possa ser incorporado à bateria de testes para avaliação do processamento auditivo, é necessário que existam critérios de normalidade para ouvintes sem alterações auditivas. O objetivo geral do presente trabalho é estabelecer critérios de normalidade para o teste GIN, em adultos com audição normal. Como objetivos específicos, têm-se: obter as médias dos limiares de detecção de gap, a porcentagem média de acertos, bem como definir um intervalo de confiança para cada uma das faixas-teste que compõem o GIN; obter o desempenho por intervalo de gap; verificar o efeito das variáveis orelha, gênero e faixa-teste. O teste GIN foi aplicado em 100 indivíduos (50 do gênero feminino e 50 do gênero masculino), de faixa-etária entre 18 e 31 anos, após a realização de outros testes audiológicos para descartar possíveis alterações auditivas e/ou do processamento auditivo, que pudessem comprometer os resultados. Como resultados gerais, foram observados limiares de detecção de gap e porcentagens médias de acertos semelhantes para as orelhas direita e esquerda, para os gêneros masculino e feminino e para as quatro faixas-teste testadas. A média geral dos limiares de gap foi de 3,98 ms, enquanto a média das porcentagens de acertos foi de 78,89%. Foi definido um intervalo de confiança (limite mínimo e limite máximo) para cada uma das faixas-teste (Média dos limiares de detecção de gap - faixa-teste 1: 3,73 - 4,01 ms; faixa-teste 2: 3,9 - 4,18 ms; faixa-teste 3: 3,88 - 4,14 ms; faixa-teste 4: 3,9 - 4,14 ms; Porcentagens médias de acertos - faixa-teste 1: 78,14 - 80,52%; faixa-teste 2: 77,34 - 79,66%; faixa-teste 3: 77,73 - 79,83%; faixa-teste 4: 77,82 - 80,14%). A curva do desempenho dos participantes por intervalo de gap foi estabelecida da seguinte forma: para gaps de 2 ms, a porcentagem de acertos foi sempre igual ou menor do que 5%; para 3 ms, esta porcentagem já fica em torno de 10 a 30%; para intervalos de 4 ms, as porcentagens de acerto chegam ao redor de 60 a 70%; para intervalos de gap iguais ou maiores do que 5 ms, a porcentagem de acertos alcança 90% ou mais. Todos estes resultados poderão ser utilizados como parâmetros de normalidade. Desta forma, o teste em questão mostrou-se consistente e com baixa variabilidade, em relação aos dados obtidos para os 100 indivíduos. / Auditory temporal resolution ability refers to the shortest time required to segregate or to resolve acoustic events. This ability is important to human speech comprehension and it is a prerequisite condition for both linguistic and reading abilities. In 2003, Musiek developed a clinical test to measure gap detection thresholds - the GIN Test - Gap In Noise (Musiek et al., 2004). In order to incorporate the GIN test to auditory processing evaluation, it is necessary to established norms in normal hearing subjects. The aims of this study were: to establish parameters for the GIN test in normal-hearing young adults; to obtain both gap detection threshold and percentage of correct responses mean; to define a confidence interval to the four lists that compound GIN test; to get a performance slope for each gap interval; to verify the variable effect concerning ear, gender and list. Proceed by an audiological evaluation to exclude hearing loss and/or auditory processing disorders, the GIN test was applied in 100 subjects (50 females and 50 males), ranged from 18 to 31 years old. Results indicated that the gap detection threshold and the percentage of correct responses means were quite similar in both right and left ears, in male and female gender and in the four tested lists. The gap detection threshold mean was 3,98 ms, and the percentage of correct responses mean was 78,89%. A confidence interval was defined (minimum and maximum limits) to each one of four lists (Gap detection threshold mean - List 1: 3,73 - 4,01 ms; List 2: 3,9 - 4,18 ms; List 3: 3,88 - 4,14 ms; List 4: 3,9 - 4,14 ms; Percentage of correct responses mean - List 1: 78,14 - 80,52%; List 2: 77,34 - 79,66%; List 3: 77,73 - 79,83%; List 4: 77,82 - 80,14%). The performance slope for each gap interval was determined according to the following criteria: to 2 ms gap interval the percentage of accurate responses were less or equal 5%; to 3 ms gap interval it varied from 10% to 30%; to 4 ms gap interval, accurate responses were from 60 to 70%; and, finally, from 5 ms and to upper intervals a 90 or more percentage was achieved. All achieved results may be applied as standard parameters. Finally, the GIN test demonstrated be consistent and to have low variability in relation to the data from the 100 subjects.