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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.
1

Les métamorphoses de l'intériorité : roman et psyché dans leur déroulememt historique : analyse historique et comparative du phénomène entre la philosophie et le discours romanesque

Uziel, Lidia January 2006 (has links)
Thèse numérisée par la Direction des bibliothèques de l'Université de Montréal.
2

Modélisation et méta-analyse des effets du domaine d’action motrice pratiqué sur la conduite et la prise de décision motrices des sportifs : étude quasi-expérimentale au moyen d’un modèle de simulation électronique et numérique / Modeling and meta-analysis of motor domain practice effect's on motor activities and decision-making of athletes : quasi-experimental study using a numeric and electronic simulation model

Ben Ali, Boubaker 06 December 2018 (has links)
Les contraintes liées au système de signes véhiculés par le comportement humain multiplient les difficultés face à toutes les formes d‘analyses, particulièrement celles qui se fondent sur l‘observation. Par exemple, les jeux sportifs peuvent, par leur richesse et leur complexité, restreindre le jugement de l‘observateur, notamment lorsqu‘il s‘agit d‘étudier des conduites et des prises de décisions motrices in situ, là où le pratiquant évolue dans un rapport consubstantiel avec son environnement. C‘est à ce niveau que les recherches en praxéologie proposent l‘analyse de la logique interne des situations ludosportives à travers une démarche systémique et structurale et une classification de pratiques sportives et ludomotrices en huit domaines d‘action motrice distincts. Les poutres maîtresses de ces domaines d‘action sont : la nature du rapport du sujet avec le milieu physique (milieu certain ou incertain) ainsi que la présence d‘interaction motrice liée à la présence d‘adversaires et/ou de partenaires. Nous avons mené une méta-analyse de trois domaines d‘action motrice au coeur desquels les sportifs pratiquent dans un milieu domestiqué, dont un domaine psychomoteur (agir en solo) et deux domaines sociomoteurs (agir contre des adversaires et agir avec des partenaires et des adversaires). Nous avons adopté une démarche méthodologique qui fait appel à l‘outil de modélisation électronique et numérique. Ce travail s‘articule autour de la science de l‘action motrice, des sciences de l‘Éducation, de la didactique des APS et des sciences de l‘ingénierie électronique et numérique. La problématique tente de mettre en évidence les effets potentiels d‘une pratique motrice régulière de trois domaines d‘action distincts sur les conduites et les prises de décision motrices. Autrement dit, chaque domaine d‘action motrice comprend des activités ludomotrices homogènes au regard de leurs traits de logique interne, influençant ainsi certains schémas d‘actions spécifiques sur la conduite motrice du pratiquant, propices au façonnage d‘habitus moteurs. Les investigations se construisent autour d‘un modèle expérimental spécifique appelé « B-percept® », modèle créé à partir d‘un jeu ludomoteur traditionnel, le « jeu des Quatre coins ». Ce système de mesures innovant et évolutif est utilisé pour évaluer et comparer les conduites de sportifs des trois domaines précités et de non-sportifs. Le protocole B-percept® mesure la vitesse de réaction simple et complexe, tant visuelle que sonore des pratiquants. Par ailleurs, outre les observations des sportifs agissants, nous avons proposé des tests de prédictions de score et d‘estime de soi (PSPP) et un entretien post-test avec les sujets, ceci afin de mieux appréhender et comprendre les conduites motrices exécutées. Les résultats obtenus ont montré qu‘une pratique sportive influencerait de manière positive le temps de réaction simple et complexe des sportifs par rapport aux non-pratiquants de sports. De surcroit, elle pourrait développer significativement leur sentiment d‘auto-efficacité, ce qui se traduirait par une meilleure capacité de prédiction des scores dans les tests B-percept®. Globalement, on relève aussi des résultats plus tranchés entre les domaines sociomoteur et psychomoteur, notamment dans la prise de décision au cours des situations complexes. Ces résultats ont été vérifiés à travers une méta-analyse par domaines, par algorithme moteur et par habitus moteurs. Fort de ces résultats, le modèle B-percept® pourra trouver des extensions dans le domaine de l‘enseignement en éducation physique et sportive, de l‘entrainement sportif et dans les centres de formation des élèves à besoins spécifiques. Dans le champ de l‘EPS, notre objectif est de contribuer à la réflexion et à la conception des contenus et de la programmation des activités physiques et sportives en ciblant, de façon pertinente et cohérente, les choix des situations motrices selon les domaines d‘action ludomotrice. / In sports and physical activities, gestures often carry an affective connotation. However the constraints due to their complexity when used in the communication process as signs system produced by human behavior could multiply difficulties on the of scientific analyses and studies. Thus, methods used to interpret the human movements and gestures have evolved in last decades, due to an increasing use of quantitative data. Nowadays researchers are working on decision-making by collecting behavioral significant information, especially during human-interactions in sports activities. Thus, since more than forty years, researches such as in motor praxeology analysis the internal logic of sports practices through systemic and structural analyses. Consequently a classification of sports activities was raised and gave eight different domains of motor action. These domains are based on the nature of physical environment (certain or uncertain environment), the attendance of opponents and/or partners. The aim of this thesis is to propose a systemic and structural methodological approach by comparing through a meta-analysis the impact of a regular sports practice in three different domains of motor activities on motor-behavior and decision-making. Our approach is built on an experimental model previously established by modeling the paradoxal game called the ―four corners game‖. Thus a smart wireless system for modeling visual and auditory searching behavior was conceived for measuring simple and complex reaction time. B-percept® helps as well to make observations, self-efficacy survey, test score-predictions and personal self-physical profile. This research allowed us to find relevant results. However, we need to be cautious about their generalization. Indeed, we have found that practicing sport positively influences the simple and complex reaction times and significantly increases self-efficacy of sports practitioners. Moreover, they could have a better ability to predict their scores at B-percept® tests. Meta-analysis through sports specialties and habitus were proceeded to improve results‘ analyzes, however, we still needing several investigations through future researches to propose a generalization of the equation model of B-percept®. In the near future, this experimental new model will be available for researchers in physical education and sports, teachers and coaches. It could also be proposed to training centers for students with special needs (handicap). We are looking forward helping to improve scholar programs made from sports activities as to be classified through the domain of actions.
3

Estimativa percepto-motora em crianças com desenvolvimento típico e atípico / Perceptual motor estimation in children with typical and atypical development

Nobre, Glauber Carvalho 16 December 2011 (has links)
Made available in DSpace on 2016-12-06T17:06:51Z (GMT). No. of bitstreams: 1 Glauber Nobre.pdf: 4529390 bytes, checksum: 16098a0d0e3bfa042272534bab17c521 (MD5) Previous issue date: 2011-12-16 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Introduction: children with atypical development have shown in a greater degree, difficulties to estimate their own ability to perform motor actions, when compared to children with typical development. However, factors such as age and gender still have to be investigated. Objective: to investigate age and gender-related changes in the Percept Motor Estimation of children with typical and atypical development. Method: This study was conducted with 7-12 years old individuals: 65 children with typical development and 63 with atypical development. In order to select the groups of children the Movement Assessment Battery for Children - Second Edition (MABC-2) was used. We evaluated the percept motor estimation at two motor tasks (horizontal jump and reach with the foot). Results: In a general manner the two groups showed difficulties in estimating their own ability to perform both motor tasks. However, individuals with atypical development, demonstrated greater difficulties and tended to underestimate or overestimate to a greater extent, the percept motor estimation to perform the horizontal jump and to reach with the foot. In this study, age and gender did not show significant effects in Percept Motor Estimation in both groups. Conclusion: In this study, in spite the results suggest an influence of age and gender on the percept motor estimation in children with typical and atypical development, it was not possible to found statistical significance. In fact, children with atypical development probably have higher difficulties in estimating correctly their limits for action on motor tasks and may feel even more discouraged to join and remain in practical motor contexts or other potentially challenging environments and therefore learning. / Introdução: crianças com desenvolvimento atípico têm demonstrado, em maior grau, dificuldade para estimar a própria capacidade de realizar ações motoras, quando comparadas as crianças que apresentam desenvolvimento típico. No entanto, fatores como idade e sexo ainda precisam ser melhor investigados. Objetivo: Investigar mudanças relacionadas à idade e sexo na estimativa perceptomotora de crianças com desenvolvimento típico e atípico. Método: este estudo foi realizado com 128 indivíduos sendo 65 crianças consideradas típicas e 63 crianças com desenvolvimento atípico nas faixas etárias de 7 a 12 anos de idade. Para selecionar os grupos de crianças utilizou-se a bateria de testes Movement Assessment Batery for Children second edition (MABC-2). Avaliou-se a estimativa perceptomotora em duas tarefas motoras (saltar horizontalmente e alcançar com o pé). Resultados: de um modo geral os dois grupos apontaram dificuldades em estimar a própria capacidade para realizar as duas tarefas motoras. Entretanto, os indivíduos com desenvolvimento atípico, demonstraram maiores dificuldades e tenderam a subestimar ou superestimar em maior grau, a estimativa perceptomotora para realização do salto e do alcançar com o pé. Neste estudo, a idade e o sexo não apontaram efeitos genuínos significativos na estimativa perceptomotora em ambos os grupos. Conclusão: neste estudo, embora os resultados sugiram uma influência da idade e do sexo na estimativa percepto-motora de crianças com desenvolvimento típico e atípico nas duas tarefas investigadas, não foi possível comprovar estatisticamente um efeito genuíno. O fato é que as crianças consideradas com desenvolvimento atípico provavelmente tem maiores dificuldades em estimar corretamente os limites para ação em tarefas motoras e podem sentir-se ainda mais desencorajadas a aderir e permanecer em contextos de prática motora ou em outros ambientes potencialmente geradores de desafio e conseqüentemente de aprendizagem.
4

Färgen och den fysiologiska estetiken : Goethe, Novalis och Caspar David Friedrich

Enström, Anna January 2009 (has links)
No description available.
5

Borderline psychopathology and the defense mechanism test

Sundbom, Elisabet January 1992 (has links)
The main purpose of the present studies has been to develop the Defense Mechanism Test (DM1) for clinical assessment of severe psychopathology with the focus on the concept of Borderline Personality Organization (BPO) according to Kemberg. By relating the DMT and the Structural Interview to each other, the concurrent validity of the concept of Personality Organization (PO) for psychiatric inpatients has been investigated. Two different assessment approaches have been used for this purpose. One has been to take a theoretical perspective as the starting-point for the classification of PO by means of the DMT. The other has been a purely empirical approach designed to discern natural and discriminating patterns of DMT distortions for different diagnostic groups. A dialogue is also in progress between DMT and current research on the Rorschach test in order to increase understanding of borderline phenomena and pathology. The overall results support Kemberg's idea that borderline patients are characterized by specific intrapsychic constellations different from those of both psychotic and neurotic patients. Both the DMT and the Structural Interview provide reliable and consistent judgements of PO. Patients with the syndrome diagnosis Borderline Personality Disorder exhibit different perceptual distortions from patients suffering from other personality disorders. The classic borderline theory is a one-dimensional developmental model, where BPO constitutes a stable intermediate form between neurosis and psychosis. The present results suggest that a two-dimensional model might be more powerful. Hence, the level of self- and object representations and reality orientation might be considered both from a developmental gad an affective perspective across varying forms of pathology. Kemberg suggests that borderline and psychotic patients share a common defensive constellation, centered around splitting, organizing self- and object representations. This view did not find support. The defensive pattem of the BPO patients is significantly different from the PPO defensive pattern. The BPO patients form their self- and object images affectively and thus the self- and object representations would seem to influence the defensive organization and not the other way around. The results have implications for the procedure and the interpretation of the DMT e.g. one and the same DMT picture can discern different kinds of personality; reactions other than the operationalized defense categories in the DMT manual can be valid predictors of PO; some of the DMT defenses described in the manual have to be reconceptualized such as isolation, repression and to some degree denial. Multivariate models are powerful tools for the integration of reactions to DMT into diagnostic patterns. / <p>Diss. (sammanfattning) Umeå : Umeå universitet, 1992, härtill 4 uppsatser.</p> / digitalisering@umu
6

Att fostra demokratiska medborgare : Hur lärare möjliggör demokratifostran i ämnet samhällskunskap för årskrurs 4-6 / To educate democratic citizens : How teachers enable democracy education in social studies in grade 4-6

Westberg, Ida January 2021 (has links)
The purpose of the study is to investigate teachers’ perceptions regarding the task of raising pupils into democratic citizens. Therefore, I will investigate how teachers apply this task in teaching. Research shows that Swedish adolescents to a very small extent engage in democtatic processes, compared to other countries. At the same time, the amount of studies performed in Sweden is very limited regarding how teachers integrate the assignment of democracy in primary school, specifically in year 4-6. Thus, it sparked an interest in how teachers apply and include the civics subject. The study was conducted by a qualitative in terms of semi-structured interviews. Six teachers participated and everyone are currently teaching civics in grade 4-6. The theoretical approach has been based on John Dewey and pragmatism. The theory has been used in combination with previous research to analyze the statements of the respondents.   Firstly, the results show that teachers experience their role of educating democratic citizens as unique and important. They believe that there are great opportunities in affecting students' roles as democratic citizens. However, the teachers also describe certain difficulties while teaching about the democratic processes, since the subject is very complex. A large part in the complexity is that school accommodates many different individuals with various sociocultural backgrounds, perceptions and opinions about the world, which constantly needs to be addressed. Additionally, the teachers also experience that using assignments where students actively practice democratic participation should be given a larger share in school. The most effective way to practice this, according to the teachers, is by using communicative methods, e.g., conversations. Finally, the studies conclude that there is a need for developing the communicative parts in the education materials, especially concerning the democracy education. / Syftet med studien är att undersöka hur verksamma lärare ser på uppdraget att fostra demokratiska medborgare. Därför kommer jag att undersöka hur lärare applicerar detta uppdrag i undervisningen. Forskning visar att svenska ungdomar i mycket liten utsträckning engagerar sig i demokratiska frågor jämfört med andra länder. Samtidigt finns det en mycket begränsad forskning vad gäller hur lärare applicerar demokratiuppdraget i grundskolans årskurs 4-6. Det skapade ett intresse för hur lärare tillämpar och inkluderar demokratiuppdraget i ämnet samhällskunskap. Undersökningen genomfördes med en kvalitativ metod genom semistrukturerade intervjuer. Det deltog sex lärare, samtliga verksamma i ämnet samhällskunskap för grundskolans mellanår, årskurs 4-6. Den teoretiska ansatsen utgår från John Dewey och pragmatismen. Teorin har sedan tillsammans med tidigare forskning använts för att analysera och diskutera respondenternas utsagor.   Resultatet visar att lärare upplever sig ha en mycket viktig och unik roll i att fostra demokratiska medborgare. De anser att det finns stora möjligheter att påverka eleverna i deras medborgarskap. Lärare ser också vissa svårigheter i fostrandet då det stundtals är mycket komplext. En stor del i komplexiteten uppges vara att skolan rymmer många individer med olika sociokulturella bakgrunder, uppfattningar och åsikter om världen som alltid måste bemötas. Lärare uttrycker också att övningar där elever praktiskt tränar på det demokratiska deltagandet bör få en större plats i skolan. I resultatet framgår även att lärare ser kommunikativa metoder i form av samtal som den mest effektiva metoden. Resultatet visar på ett behov av att utveckla de kommunikativa delarna i läromedlen som riktar sig mot demokratiundervisningen.
7

Understanding the Aesthetics of New Media Art as the Ontological Play of Becoming

Youn, Haeyoung January 2022 (has links)
No description available.
8

Advancing the Interhemispheric Switch Model of Perceptual Rivalry

Trung Thanh Ngo Unknown Date (has links)
Perceptual rivalry refers to visual phenomena that are characterised by alternations between different percepts, despite an unchanging sensory input. Two common types of perceptual rivalry are (i) reversible figures — two-dimensional stable images that when viewed, are perceived to switch between different interpretations, and (ii) binocular rivalry — the alternations in image dominance resulting from the presentation of conflicting stimuli, one to each eye. Several investigators have suggested that these rivalling phenomena are mediated by similar neural mechanisms. Such a view, however, has not only been inadequately substantiated, but has also yet to be assessed in the context of a directly testable neurophysiological model. Miller and Pettigrew have proposed a novel, high-level interhemispheric switch (IHS) explanatory model of binocular rivalry. This model conceptualises the perceptual alternations as being mediated by alternations between one hemisphere’s selected image and the other hemisphere’s selected (rival) image. To assess their hypothesis, caloric vestibular stimulation (CVS) was used. CVS is a simple, inexpensive, and non-invasive brain stimulation technique that unilaterally activates high-level attentional areas. In accordance with the IHS model, CVS was found to significantly affect predominance (the duration that one image is perceived relative to the other, within a given viewing period) during conventional binocular rivalry with horizontal/vertical gratings and with orthogonal oblique gratings. The present thesis therefore aims, through the use of CVS, to extend this IHS model of binocular rivalry to reversible-figure alternations and propose a general IHS model of perceptual rivalry. Chapter 1 provides a detailed literature review of the field within the context of comparing both perceptual rivalries. In Chapter 2, investigations are presented on two different reversible figures — the perspective-reversing Necker cube and the figure–ground reversing Rubin’s vase–faces illusion. In these experiments, CVS was found to significantly change observers’ predominance compared to their baseline predominance. These results demonstrate that interhemispheric switching also mediates the alternations of these visual phenomena, in addition to binocular rivalry, thereby extending the IHS model to one of perceptual rivalry in general. Moreover, the findings are interpreted in a cognitive neuroscience context, including a novel proposal of a forebrain framework for the IHS model. Chapter 3 presents CVS experiments that address the issue of percept–to–hemisphere selection and the reproducibility of CVS effects, following Miller’s initial work on two types of conventional binocular rivalry. In planned analyses, significant predominance changes were not found in horizontal/vertical rivalry, oblique rivalry and Necker-cube rivalry. In post-hoc analyses that accounted for study-design differences between Miller’s original experiments and the present experiment, CVS was again not shown to induce significant predominance changes in any of the rivalry types. Assessment of directional predominance changes following CVS appeared to suggest an arbitrary selection of percept–to–hemisphere in all rivalry types, although no firm conclusions could be drawn from the obtained data on this issue. Nevertheless, the experiments further extend upon Miller’s earlier work by examining the inter- and intra-individual reproducibility of CVS-induced effects on predominance. Such reproducibility was found to be low and potential reasons for this are discussed. The experiments in Chapter 4 examine a type of binocular rivalry in which dichoptic presentation of Díaz-Caneja stimuli yields rivalry among four different stable images: half-field rivalry between the images presented to the eyes, and coherence rivalry in which aspects of each eye’s presented image are perceptually regrouped into rivalling coherent images. Each of these rivalries was found to occur for about half the given viewing time. Furthermore, CVS significantly shifted the predominance of perceived coherent images (coherence rivalry) but not half-field images (eye rivalry). This finding suggests that coherence rivalry (like conventional rivalry according to previous experiments) is mediated by interhemispheric switching at a high level, while eye rivalry is mediated by intrahemispheric mechanisms, most likely at a low level. In addition, it is proposed that Díaz-Caneja stimuli induce ‘meta-rivalry’ whereby these discrete high- and low-level competitive processes themselves rival for visual consciousness. The current thesis thus presents a novel meta-rivalry model of multistable binocular rivalry. It also presents the first direct evidence that interhemispheric switching mediates reversible-figure alternations, thereby supporting a generalised IHS model of perceptual rivalry. It is argued that both models provide a parsimonious exploratory framework within which specific predictions can be made and readily tested. Finally, the findings of all experiments in the current thesis are summarised.
9

Advancing the Interhemispheric Switch Model of Perceptual Rivalry

Trung Thanh Ngo Unknown Date (has links)
Perceptual rivalry refers to visual phenomena that are characterised by alternations between different percepts, despite an unchanging sensory input. Two common types of perceptual rivalry are (i) reversible figures — two-dimensional stable images that when viewed, are perceived to switch between different interpretations, and (ii) binocular rivalry — the alternations in image dominance resulting from the presentation of conflicting stimuli, one to each eye. Several investigators have suggested that these rivalling phenomena are mediated by similar neural mechanisms. Such a view, however, has not only been inadequately substantiated, but has also yet to be assessed in the context of a directly testable neurophysiological model. Miller and Pettigrew have proposed a novel, high-level interhemispheric switch (IHS) explanatory model of binocular rivalry. This model conceptualises the perceptual alternations as being mediated by alternations between one hemisphere’s selected image and the other hemisphere’s selected (rival) image. To assess their hypothesis, caloric vestibular stimulation (CVS) was used. CVS is a simple, inexpensive, and non-invasive brain stimulation technique that unilaterally activates high-level attentional areas. In accordance with the IHS model, CVS was found to significantly affect predominance (the duration that one image is perceived relative to the other, within a given viewing period) during conventional binocular rivalry with horizontal/vertical gratings and with orthogonal oblique gratings. The present thesis therefore aims, through the use of CVS, to extend this IHS model of binocular rivalry to reversible-figure alternations and propose a general IHS model of perceptual rivalry. Chapter 1 provides a detailed literature review of the field within the context of comparing both perceptual rivalries. In Chapter 2, investigations are presented on two different reversible figures — the perspective-reversing Necker cube and the figure–ground reversing Rubin’s vase–faces illusion. In these experiments, CVS was found to significantly change observers’ predominance compared to their baseline predominance. These results demonstrate that interhemispheric switching also mediates the alternations of these visual phenomena, in addition to binocular rivalry, thereby extending the IHS model to one of perceptual rivalry in general. Moreover, the findings are interpreted in a cognitive neuroscience context, including a novel proposal of a forebrain framework for the IHS model. Chapter 3 presents CVS experiments that address the issue of percept–to–hemisphere selection and the reproducibility of CVS effects, following Miller’s initial work on two types of conventional binocular rivalry. In planned analyses, significant predominance changes were not found in horizontal/vertical rivalry, oblique rivalry and Necker-cube rivalry. In post-hoc analyses that accounted for study-design differences between Miller’s original experiments and the present experiment, CVS was again not shown to induce significant predominance changes in any of the rivalry types. Assessment of directional predominance changes following CVS appeared to suggest an arbitrary selection of percept–to–hemisphere in all rivalry types, although no firm conclusions could be drawn from the obtained data on this issue. Nevertheless, the experiments further extend upon Miller’s earlier work by examining the inter- and intra-individual reproducibility of CVS-induced effects on predominance. Such reproducibility was found to be low and potential reasons for this are discussed. The experiments in Chapter 4 examine a type of binocular rivalry in which dichoptic presentation of Díaz-Caneja stimuli yields rivalry among four different stable images: half-field rivalry between the images presented to the eyes, and coherence rivalry in which aspects of each eye’s presented image are perceptually regrouped into rivalling coherent images. Each of these rivalries was found to occur for about half the given viewing time. Furthermore, CVS significantly shifted the predominance of perceived coherent images (coherence rivalry) but not half-field images (eye rivalry). This finding suggests that coherence rivalry (like conventional rivalry according to previous experiments) is mediated by interhemispheric switching at a high level, while eye rivalry is mediated by intrahemispheric mechanisms, most likely at a low level. In addition, it is proposed that Díaz-Caneja stimuli induce ‘meta-rivalry’ whereby these discrete high- and low-level competitive processes themselves rival for visual consciousness. The current thesis thus presents a novel meta-rivalry model of multistable binocular rivalry. It also presents the first direct evidence that interhemispheric switching mediates reversible-figure alternations, thereby supporting a generalised IHS model of perceptual rivalry. It is argued that both models provide a parsimonious exploratory framework within which specific predictions can be made and readily tested. Finally, the findings of all experiments in the current thesis are summarised.
10

Development of Pitch Perception Indexed By Infant Mismatch Responses

He, Chao 11 1900 (has links)
<p> Hearing provides a vital means for infants to discover their environment and communicate with their caregivers. Identifying and discriminating the pitch of sounds is critical for infants in order to acquire information from speech and music. Therefore, how infants process pitch is a fundamental question in research on auditory development. The focus of this dissertation is the use of auditory event related potentials (ERPs) derived from electroencephalogram (EEG) recordings to examine the maturation of pitch perception in early infancy. </p> <p> Pitch perception in adults has been extensively studied, but little is known about the development of pitch perception during early infancy. Infant mismatch responses (MMRs) are ERP components that are elicited by infrequent changes in auditory stimuli. MMR is a promising tool to study infant pitch perception because it can be elicited without attention or a behavioural response. However, previous studies on MMRs in infants have reported inconsistent results, some reporting frontally positive responses while others report frontally negative mismatch responses. In Chapter 2, we examined MMRs to simple pitch changes in infants between 2 and 4 months of age and found both types of infant MMRs are present, but the morphological distributions and developmental trajectories are different. In Chapter 3, we reported that both types of infant MMRs are affected similarly by the amplitude of pitch change but only the positive MMR becomes stronger when stimulus presentation rate increases, which suggests different neural mechanisms for the two types of infant MMRs. The studies reported in Chapter 4 found that only the negative MMR can be elicited readily by changes in pitch patterns, suggesting that it may be functionally similar to mismatch negativity (MMN) in adults. </p> <p> The experiments in Chapter 5 used MMR as the indication of whether infants automatically integrate the frequency components of a complex tone into a single pitch percept, even when the fundamental frequency component (corresponding to the pitch) is removed. Previous studies show that adult MMN is elicited by a pitch change in such tones missing the fundamental. Previous behavioural studies using a conditioned head tum method show that 7-month-olds also perceive pitch with tones missing the fundamental. The results of the present study indicate that infants as young as 4 months of age integrate components into a single pitch percept, but evidence for this in younger infants could not be found. </p> <p> In conclusion, the current dissertation established a promising procedure utilizing infant MMR to study infant pitch perception and contributed to the knowledge of early development of pitch perception by demonstrating dramatic changes in brain response to pitch in harmonic tones in infants between 2 and 4 months old, and to pitch in tones in infants missing the fundamental between 3 and 4 months old . </p> / Thesis / Doctor of Philosophy (PhD)

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