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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
111

De l'intimité à la complicité : la chanson-action comme organisateur de l'attention chez le bébé de trois à six mois. / From intimacy to complicity : how do action-songs organize attention in 3- to 6-months-old infants.

Delavenne, Anne 17 February 2011 (has links)
L’objectif de cette recherche est d’étudier la coordination temporelle entre l’organisation de la performance maternelle (chant et gestes des mains), les variations de l’attention visuelle et la vocalisation du bébé à 3 mois et à 6 mois au cours de la ‘chanson-action’ française ‘les marionnettes’. Le terme ‘chanson-action’ désigne des routines interactives associant une ‘mise en scène’ des mains (ici de la mère) coordonnée à un chant pour bébé. Le ‘chanter-bébé’ fait partie des premières stimulations musicales du bébé. Des recherches expérimentales ont mis en évidence qu’il possède plusieurs fonctions et qu’en particulier il maintient l’attention du bébé au cours des échanges. Les ‘chansons-actions’ apparaissent dans le cours des interactions précoces un peu avant le milieu de la première année du bébé. Or des expériences ont montré qu’à cet âge précoce le bébé semble déjà capable de partager son attention entre la mère et un autre centre d’intérêt dans certaines conditions, en particulier lorsque la mère manipule un objet familier. Les ‘chansons-actions’ apparaissent alors comme une situation naturelle permettant d’étudier l’aptitude du bébé à partager son attention. Nous avons donc cherché à tester l’hypothèse centrale selon laquelle l’organisation hiérarchisée de la performance maternelle et en particulier du chant devait fournir un cadre organisant les variations dynamiques de l’attention visuelle du bébé. Nous pensions de plus que l’organisation temporelle de ses vocalisations devait refléter sa sensibilité à cette organisation musicale et qu’il devait vocaliser à des moments saillants de la chanson-action. Nous avons choisi d’étudier les échanges de mêmes dyades à 3 mois et à 6 mois car ces âges sont périphériques à l’émergence spontanée des ‘chansons-actions’ dans le répertoire des routines interactives de la mère et du bébé. Nous voulions ainsi explorer l’évolution de la coordination entre l’organisation temporelle de la performance maternelle et les variations de l’attention du bébé.Nous avons étudié les échanges de 20 dyades à 3 mois (12 dyades ‘mère-garçon’ et 8 dyades ‘mère-fille’) et de 18 de ces mêmes dyades à 6 mois (10 dyades ‘mère-garçon’ et 8 dyades ‘mère-fille’). L’originalité de notre recherche est d’explorer l’évolution dynamique des variations de l’attention du bébé au cours de la chanson-action... / The aim of this study was to analyze the temporal coordination between the organization of the maternal performance (singing and hand gesturing), the visual attention and vocalization of the infant at 3- and 6-months during sequences of the French ‘action-song’ ‘les marionnettes’. The word ‘action-song’ is used to refer to interactive routines that combine hand gestures coordinated with a baby song. Infant-directed singing has been shown to be among the first musical stimulations addressed infants. Experimental studies have demonstrated that it possesses several functions and that one of them is maintaining the infant’s attention. Action-songs emerge in interactions at about 4-months. Experimental studies have proved that the infant exhibits the ability to share her attention between the mother and another object of interest, in particular when it is a familiar object that the mother holds in her hands. Actions-songs appear to be a natural situation that allows us to study this ability. We tested the central hypothesis that the hierarchical levels of maternal singing performance would provide a frame that would organize the dynamic variations of the infant’s visual attention. Moreover the infant would vocalize at specific moments of the musical structure of maternal singing. We studied the exchanges of the same dyads at 3- and 6-months to explore the developmental trajectory of the coordination between the temporal organization of the maternal performance and the infant’s visual attention.We studied the interactions of 20 dyads at 3 months (12 boys and 8 girls) and of 18 of those dyads at 6 months (10 boys and 8 girls). We performed both video and acoustic microanalyses to study the dynamic variations of infant’s attention during the action-song. Thus, each gaze orientation of the infant was associated with a specific element of the maternal singing. Our results showed that maternal singing was articulated at three hierarchical temporal levels (verse, line, pulse) both at 3- and at 6-months. At 3 months the infant’s attention was oriented mainly towards the mother’s face. The variations of the infant’s attention were coordinated with the phrasing of maternal singing and the infant reoriented her attention towards the hands just before the end of the verse. Infants’ vocalizations also occurred at the end of the verse. At 6-months, infants were more attentive to the mother’s hands. Six-month-olds reoriented her attention towards the mother’s face at the end of the verse. Infants’ vocalizations were synchronized with pulse of the maternal singing. Furthermore our results exhibited gender differences at 3- and at 6-months. The performance of mothers of boys was more regular than the performance of mothers of girls. We suggest that actions-songs provide a frame that scaffolds the ability of the infant to share her attention between the mother’s face and hands.
112

Acoustic Tonal and Vector Properties of Red Hind Grouper Vocalizationd

Unknown Date (has links)
Vertebrates are the most prodigious vocalizing animals in existence, and the most diverse methods of acoustic communication among vertebrates can be found in the ocean. Relatively many teleost fish are gifted with the ability to communicate acoustically, and the family of serranidae often performs this as a function of the swim bladder. Epinephelus Guttatus (E. guttatus), or more commonly the red hind grouper, is equipped with a drum shaped swim bladder acting as a monopole under typical ocean conditions. This configuration allows for what is understood to be omnidirectional projection of tones approximately centered between 40 and 440 Hz and spanning anywhere from 40 to 200 Hz of bandwidth and modulation effects based on observed data provided by researchers. Prior studies on many other fish show correlation in acoustic communication profile with length, size and sexual identity. In the red hind, sexual dimorphism leads to an inherent female identity in all juvenile fish which converts to male according to environmental factors, recommending at least consistent organs across both sexes be assumed even if not in use. Much research has been performed on male fish vocalization in terms of spectral content. Communication in fish is a complex multi-modal process, with acoustic communication being important for many of the species, particularly those in the littoral regions of the worlds’ oceans. If identifying characteristics of the red hind vocalization can be isolated based on detection, classification, tracking and localizing methodologies, then these identifying characteristics may indeed lead to passive feature identification that allows for estimation of individual fish mass. Hypotheses based on vector, cyclostationary and classical tonal mechanics are presented for consideration. A battery of test data collection events, applying pre-recorded fish vocalizations to a geolocated undersea sound source were conducted. The results are supplied with the intent of validating hypothesis in a non-expert system manner that shows how a series of biological metrics may be assessed for detection, classification, localization and mass estimation for an individual vocalizing red hind grouper / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2017. / FAU Electronic Theses and Dissertations Collection
113

Análise do repertório vocal de Pitangus sulphuratus (Linnaeus, 1766) (Aves Passeriformes: Tyrannidae) em diferentes regiões do Brasil /

Rodrigues, Fernanda Gonçalves January 2017 (has links)
Orientador: Reginaldo José Donatelli / Resumo: O bem-te-vi, Pitangus sulphuratus, é um dos pássaros mais comuns em quase todo o Brasil e considerado o mais popular deste país. Apresenta um comportamento altamente versátil e generalista, e encontra alimento facilmente em qualquer hábitat, tendo uma ampla distribuição geográfica, sendo encontrado do Texas ao sul da Argentina. No Brasil ocorrem quatro subespécies, que apresentam diferenciações nas cores da plumagem do dorso e do ventre. Inserido na Classe Aves, ordem Passeriformes, subordem Suboscines, tem o seu canto considerado inato, já que se desenvolve normalmente na ausência de um modelo auditivo. As aves Suboscines são bons modelos de análise vocal entre populações, já que quaisquer diferenças entre suas vocalizações não poderiam ser atribuídas aos padrões culturais de aprendizado. Considerando-se que o ambiente exerce uma seletividade na transmissão do som, indivíduos de uma mesma espécie podem apresentar diferenças vocais por estarem em ambientes diferentes; sendo assim, a localização pode exercer uma padronização ou diferenciação nas vocalizações das aves. Neste trabalho foram utilizadas 288 vocalizações de Pitangus sulphuratus, os quais foram classificados de acordo com sua sintaxe. Realizaram-se análises estruturais acústicas para a comparação e identificação de possíveis variações vocais entre as populações das subespécies presentes no Brasil e correlação com a altitude, latitude, longitude, bem como variáveis bioclimáticas (temperatura e precipitação). Foram id... (Resumo completo, clicar acesso eletrônico abaixo) / Mestre
114

Detection and classification of marine mammal sounds

Unknown Date (has links)
Ocean is home to a large population of marine mammals such as dolphins and whales and concerns over anthropogenic activities in the regions close to their habitants have been increased. Therefore the ability to detect the presence of these species in the field, to analyze and classify their vocalization patterns for signs of distress and distortion of their communication calls will prove to be invaluable in protecting these species. The objective of this research is to investigate methods that automatically detect and classify vocalization patterns of marine mammals. The first work performed is the classification of bottlenose dolphin calls by type. The extraction of salient and distinguishing features from recordings is a major part of this endeavor. To this end, two strategies are evaluated with real datasets provided by Woods Hole Oceanographic Institution: The first strategy is to use contour-based features such as Time-Frequency Parameters and Fourier Descriptors and the second is to employ texture-based features such as Local Binary Patterns (LBP) and Gabor Wavelets. Once dolphin whistle features are extracted for spectrograms, selection of classification procedures is crucial to the success of the process. For this purpose, the performances of classifiers such as K-Nearest Neighbor, Support Vector Machine, and Sparse Representation Classifier (SRC) are assessed thoroughly, together with those of the underlined feature extractors. / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2014. / FAU Electronic Theses and Dissertations Collection
115

Propriedades ac?sticas das chamadas de distress emitidas por morcegos stenodermat?neos (Chiroptera: Phyllostomidae) durante manipula??o em campo / Acoustical Properties of the distress calls of Stenodermatineo bats (Chiroptera: Phyllostomidae) during handling in field

MAAS, Andrea Cec?lia Sicotti 16 December 2010 (has links)
Submitted by Jorge Silva (jorgelmsilva@ufrrj.br) on 2017-02-07T20:27:42Z No. of bitstreams: 1 2010 - Andrea Cec?lia Sicotti Maas.pdf: 2297895 bytes, checksum: 356a05153807fe7b25a4fd3042b79964 (MD5) / Made available in DSpace on 2017-02-07T20:27:42Z (GMT). No. of bitstreams: 1 2010 - Andrea Cec?lia Sicotti Maas.pdf: 2297895 bytes, checksum: 356a05153807fe7b25a4fd3042b79964 (MD5) Previous issue date: 2010-12-16 / CNPq / Studies envolving bioacustic have strongly collaborated for understanding phylogenetics, ontogenetics, environmental and behavioural processes. Vocal communication is important for the bats for navigation and food attainment, nevertheless represents a key aspect for social interactions. Several studies have demonstrated characteristics of echolocation vocalizations and other types of audio signals. However, few studies have been described with respect to of distress calls. Among these studies have described the vocalizations of distress calls as being of animals in situations of extreme danger, such as when the animal is caught by a predator or even when it is contained by a researcher. Some authors have offered hypotheses to explain a general convergence in the structure of vocalizations produced by birds and mammals in similar behavioral contexts. However, there are few studies have been done on the distress calls in bats. The present general study's objective is to produce and analyze a database for bioacoustics in the context distress vocalizations emitted by bats, analyze and describe the acoustic properties of distress vocalizations in bats of the subfamily Stenodermatinae. Data collection investigations have been carried out in five different locations within the southeast region of Brazil. For this study, were recorded vocalizations of bats in subfamily Stenodermatinae: Artibeus cinereus, Artibeus fimbriatus, A. planirostris, A. obscurus, A. lituratus, Platyrrhinus lineatus, P. recifinus and Vampyressa pusilla. The vocalizations were analyzed using the analysis system Raven v1.3. For analysis, we selected 30 calls of each individual. The following parameters were measured: Types of signs, bands tonal, duration of the signal, and interval of Pre-pulse, interval of post-pulse, minimum frequency, maximum frequency, initial frequency, maximum frequency and peak frequency. For a description of the acoustic parameters were averaged, standard deviation and coefficient of variation values of each of the measured parameters of vocalizations for each species. Through the analysis, we identify two basic types of notes for this noise present in the calls of distress among the species. The results presented here showed that the acoustic parameters corroborate other work in this same context, ie: distress vocalizations of the bat species studied may be the motivation of aggression, as the code calling the motivational structure, characterized in general for they present low frequency, in wide bands and loaded of noises. / As pesquisas com bioac?stica t?m colaborado na compreens?o de processos filogen?ticos, ontogen?ticos, ecol?gicos e comportamentais. Para os morcegos, a comunica??o vocal ? importante para navega??o e obten??o de alimentos, al?m de ser um aspecto chave nas intera??es sociais. V?rios estudos t?m demonstrado caracter?sticas de vocaliza??es de ecolocaliza??o e outros tipos de sinais aud?veis. Por?m, poucos estudos t?m sido descritos com rela??o ?s chamadas de distress. Dentre esses estudos t?m-se descrito as vocaliza??es de distress como sendo chamadas de animais em situa??es de extremo perigo, tais como quando esse animal ? capturado por um predador ou mesmo quando ? contido por um pesquisador. Alguns autores t?m apresentado hip?teses para explicar uma converg?ncia geral na estrutura das vocaliza??es produzidas por p?ssaros e mam?feros em contextos comportamentais similares. H?, entretanto, poucos estudos sendo desenvolvidos sobre as chamadas de distress em morcegos. O presente estudo tem como objetivo geral ? elabora??o e an?lise de um banco de dados bioac?sticos para vocaliza??es no contexto distress, emitidas por morcegos filostom?deos, analisar e descrever as propriedades ac?sticas das vocaliza??es de distress em morcegos da subfam?lia Stenodermatinae. As coletas dos dados bioac?sticos foram realizadas em cinco locais diferentes dentro da regi?o sudeste do Brasil. Para o presente estudo, foram gravadas vocaliza??es de morcegos da Subfam?lia Stenodermatinae: Artibeus cinereus, Artibeus fimbriatus, A. planirostris, A. obscurus, A. lituratus, Platyrrhinus lineatus, P. recifinus e Vampyressa pusilla. As vocaliza??es foram analisadas utilizando o sistema de an?lise Raven v1.3. Para an?lise, foram selecionadas 30 chamadas de cada indiv?duo. Os seguintes par?metros foram mensurados: Tipos de Sinais, bandas tonais, dura??o do sinal, Intervalo do Pr?-pulso, Intervalo do P?s-pulso, freq??ncia m?nima, freq??ncia m?xima, freq??ncia inicial, freq??ncia m?xima e freq??ncia pico. Para a descri??o dos par?metros ac?sticos foram calculados a m?dia, o desvio padr?o e o coeficiente de varia??o dos valores obtidos de cada um dos par?metros medidos das vocaliza??es para cada esp?cie. Atrav?s das an?lises, pudemos identificar dois tipos b?sicos de notas para esta emiss?o sonora presente nas chamadas de distress dentre as esp?cies estudadas. Os resultados aqui apresentados mostraram que os par?metros ac?sticos corroboram com outros trabalhos neste mesmo contexto, ou seja: as vocaliza??es de distress das esp?cies de morcegos estudadas podem representar a motiva??o de agressividade, conforme o c?digo de estrutura motivacional da vocaliza??o, caracterizadas em geral por apresentarem baixa frequ?ncia, em bandas larga e carregada de ru?dos.
116

Revisão acústica do canto de anúncio de Hylodes do grupo H. lateristrigatus (Hylodidae; Anura; Amphibia): implicações taxonômicas / Bioacoustic review of advertisement call in Hylodes lateristrigatus group (Hylodidae; Anura; Amphibia): taxonomic implications

Iguchi, Jully Mitie Santos 14 June 2013 (has links)
A comunicação acústica é um importante elemento do comportamento reprodutivo de muitos animais. Em anuros a comunicação que recebe o nome de canto de anúncio tem como principal função a atração de fêmeas coespecíficas. Assim, a vocalização é um mecanismo primário de isolamento reprodutivo, e mostra-se importante no trabalho de determinação de espécies, pois assegura uma diagnose confiável, principalmente em caso de espécies crípticas, como ocorre no gênero Hylodes. Esse gênero compreende 24 espécies descritas, encontradas quase em sua totalidade em ambientes de Floresta Atlântica, exceto por H. otavioi (mata rupestre), e sempre associadas a rios e riachos em terrenos acidentados, distribuídas do Espírito Santo ao Rio Grande do Sul. O objetivo deste trabalho foi analisar o canto de anúncio de 9 populações e revisar a descrição da vocalização das 18 espécies descritas do grupo de H. lateristrigatus. Nós realizamos a redescrição do canto de H. lateristrigatus e H. sazimai; alteramos a distribuição de H. pipilans; e detectamos três possíveis novas espécies, que estão sob análise. / The bioacoustic communication is substantial on reproductive behaviour of many animal groups. In anurans the advertisement call is the main communication signal and its major function is conspecific female attraction. Therefore, calling is the primary reproductive isolation mechanism and it is essencial in determining species, because it guarantees a reliable diagnosis specially in cryptic species as Hylodes. This genus comprises 24 species, which occur in the Atlantic Forest, with the exception of H. otavioi (Rocky Forest). Hylodes species are always related with streams and waterfalls from Espírito Santo to Rio Grande do Sul. The purpose of this study is to analyse the advertisement call of nine populations and review the calling of 18 described species of H. lateristrigatus group. We redescribed the advertisement call of H. lateristrigatus and H. sazimai; broadened the distribution of H. pipilans; and detected three probable new species that are under study.
117

Avian musing feature space analysis

Colón, Guillermo J. 24 May 2012 (has links)
The purpose of this study was to analyze the possibility of utilizing known signal processing and machine learning algorithms to correlate environmental data to chicken vocalizations. The specific musing to be analyzed consist of not just one chicken's vocalizations but of a whole collective, it therefore becomes a chatter problem. There have been similar attempts to create such a correlation in the past but with singled out birds instead of a multitude. This study was performed on broiler chickens (birds used in meat production). One of the reasons why this correlation is useful is for the purpose of an automated control system. Utilizing the chickens own vocalization to determine the temperature, the humidity, the levels of ammonia among other environmental factors, reduces, and might even remove, the need for sophisticated sensors. Another factor that this study wanted to correlate was stress in the chickens to their vocalization. This has great implications in animal welfare, to guarantee that the animals are being properly take care off. Also, it has been shown that the meat of non-stressed chickens is of much better quality than the opposite. The audio was filtered and certain features were extracted to predict stress. The features considered were loudness, spectral centroid, spectral sparsity, temporal sparsity, transient index, temporal average, temporal standard deviation, temporal skewness, and temporal kurtosis. In the end, out of all the features analyzed it was shown that the kurtosis and loudness proved to be the best features for identifying stressed birds in audio.
118

Motion selectivity as a neural mechanism for encoding natural conspecific vocalizations

Andoni, Sari 07 February 2011 (has links)
Natural sound, such as conspecific vocalizations and human speech, represents an important part of the sensory signals animals and humans encounter in their daily lives. This dissertation investigates the neural mechanisms involved in creating response selectivity for complex features of natural acoustic signals and demonstrates that selectivity for spectral motion cues provides a neural mechanism to encode communication signals in the auditory midbrain. Spectral motion is defined as the movement of sound energy upward or downward in frequency at a certain velocity, and is believed to provide the auditory system with an important perceptual cue in the processing of human speech. Using the Mexican free-tailed bat, tadarida brasiliensis, as a model system, this research examined the role of selectivity for spectral motion cues, such as direction and velocity, in creating response selectivity for specific features of the social communication signals emitted by these animals. We show that auditory neurons in the midbrain nucleus of the inferior colliculus (IC) are specifically tuned for the frequency-modulated (FM) direction and velocities found in their conspecific vocalizations. This close agreement between neural tuning and features of natural conspecific signals shows that auditory neurons have evolved to specifically encode features of signals that are vital for the survival of the animal. Furthermore, we find that the neural computations resulting in selectivity for spectral motion are analogous to mechanisms observed in selectivity for visual motion, suggesting the evolution of similar neural mechanisms across sensory modalities. / text
119

Animal cognition and animal personality: Individual differences in exploratory behaviour, learning, vocal output, and hormonal response in an avian model

Guillette, Lauren M Unknown Date
No description available.
120

Early Environment and Adolescent Ethanol Consumption : Effects on Endogenous Opioids and Behaviour in Rats

Daoura, Loudin January 2013 (has links)
Excessive and compulsive ethanol drinking is one of the most serious public health issues. Therefore, it is vital to increase the knowledge about risks and protection for alcohol use disorders (AUD) to optimize prevention and treatment strategies. Ethanol consumption commonly initiates during adolescence when extensive neuronal maturation and development also occurs. Early exposure to ethanol is a risk factor for AUD, but the effects of adolescent drinking and the basis for the individual susceptibility to AUD are not fully understood. The interactions between genotype and environmental factors determine the individual risk for AUD and this thesis aimed to examine the environmental impact. The specific aims were to investigate 1) how early-life conditions affect adolescent voluntary ethanol drinking, behavioural profiles, endogenous opioids and response to treatment with an opioid antagonist (naltrexone), and 2) whether alterations detected in the offspring may be mediated by variations in maternal behaviour. A rodent maternal separation (MS) model was used to mimic a protective and risk-inducing early-life environment, respectively, with the use of 15 min (MS15) or 360 min (MS360) of daily MS. The main findings were 1) the MS360, but not the MS15 rats, responded to naltrexone following adolescent ethanol drinking; all adolescent rats had a high voluntary ethanol intake independent of early environmental conditions whereas in the adult groups the MS360, but not the MS15 rats, increased their ethanol intake and preference over time; adolescent ethanol exposure resulted in higher dynorphin levels in hippocampus and higher Met-enkephalin-Arg6Phe7 in the amygdala, independently of rearing conditions, 2) behavioural profiling using the multivariate concentric square field™ test showed: the young MS360 rats had increased risk assessment and risk taking behaviour compared to the young MS15 rats; the young MS15 rats increased, whereas the young MS360 rats decreased, their risk assessment and risk taking behaviour over time; differences in pup-retrieval strategies where the MS360 dams retrieved some pups into a safe area but as compared to MS15 rats they left more pups in a risk area; increased risk assessment behaviour in the MS360 dams immediately after weaning. Taken together, early-life environmental conditions alter adult but not adolescent drinking, the response to naltrexone, and behaviour in dams and offspring. Adolescent rats consumed more ethanol independent of rearing conditions and displayed increased opioid levels in brain areas related to cognition and addiction.

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