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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.
61

Basic conditioning and spatial cue competition effects in an automated open-field apparatus

Leising, Kenneth James, January 1900 (has links)
Thesis (Ph. D.)--UCLA, 2008. / Vita. Description based on print version record. Includes bibliographical references (leaves 197-220).
62

Overexpectation and trial massing

Sissons, Heather T. January 2008 (has links)
Thesis (M.S.)--State University of New York at Binghamton, Department of Psychology, 2008. / Includes bibliographical references.
63

Modulação circadiana da aprendizagem e memoria em pombos : analise da sensibilização e do condicionamento classico aversivo da resposta ao som / Circadian modulation of learning and memory in pigeons: analysis of sensitization and classical fear conditioning of acoustic response

Siqueira, Luis Otavio 03 March 2006 (has links)
Orientador: Elenice Aparecida de Moraes Ferrari / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-06T20:47:31Z (GMT). No. of bitstreams: 1 Siqueira_LuisOtavio_D.pdf: 1043861 bytes, checksum: 39ebfc094cde948f0af9f82213528298 (MD5) Previous issue date: 2006 / Resumo: O comportamento exploratório garante a inspeção, a localização, a identificação e a avaliação precisa de eventos ambientais. A exploração também é abordada como sendo relacionada com a curiosidade do animal direcionada a novos estímulos. Os comportamentos reflexos que precedem as reações exploratórias, caracterizando-se, portanto, como comportamentos pré-exploratórios e também têm importante função adaptativa. Poucos estudos analisaram a influência da hora do dia sobre respostas incondicionadas e condicionadas ao som. Dessa forma, o presente estudo investigou a variação circadiana da amplitude da resposta aversiva ao som em pombos. Experimento I usou um equipamento de registro automatizado da amplitude da resposta acústica, formado por uma câmara experimental, com uma célula de carga acoplada ao piso e interface dos sinais a um microcomputador utilizado para controle, armazenamento e análise dos dados. O Experimento II analisou a sensibilização da resposta em diferentes horários do dia usando: (a) linha de base com apresentação de 5 estímulos acústicos com intervalo entre sons de 3Os; (b) treino, iniciado 5 min após o último som, com dois choques elétricos, intervalo entre choques de 5 min e (c) teste, iniciado 10 min após o último choque, com 40 estímulos acústicos. Os animais dos grupos controles permaneceram na caixa experimental sem estimulação. O Experimento 111 usou intervalos (a) entre o término da linha de base e o início do treino, (b) entre os dois choques e (c) entre o último choque e o teste foram de 1 mino O Experimento IV investigou o condicionamento clássico de traço, utilizando grupos: Experimental, com três associações som-choque; Randômico, com 3 choques e 3 sons casualizados e Controle, expostos à caixa experimental.Em todos os experimentos usou-se fotoperíodo esqueleto com pulsos de luz (15 min) às 6h (ZTOO) e às 18h (ZT12) e sub-grupos em cada horário de teste: ZT02, ZT06, ZT10, ZT14, ZT18 e ZT22. De um modo geral, os dados mostraram que tanto a sensibilização quanto o condicionamento clássico aversivo resultaram em alterações da amplitude da resposta ao som que variaram em função do horário de teste, com amplitudes máximas na transição dia-noite e mínimas na transição noite-dia. O conjunto desses dados indica a modulação do aprendizado aversivo pelo sistema temporizador circadiano / Abstract: Exploratory behavior allows the inspection, localization, identification and the correct evaluation of the environmental events. The exploration also is related with curiosity related to new stimuli. The reflex behaviors that preceed the exploratory reactions are characterized as pre- exploratory and also have an important adaptative function. There are few studies that analyse the influence of time of the day on this response. Thus, the present study investigated the circadian variation of response to aversive sounds in pigeons. Experiment I, used a new equipment especially designed for automatic recording of response of acoustic response amplitude. The system is composed by an experimental chamber, with a load cell under the floor and a computer interface for contrai, storage and data analysis. Experiment 11 analyzed the sensitization of sound response in different times of the day. The experimental protocol used: (a) baseline with 5 acoustic stimulus presentation with inter-stimulus-interval between sounds of the 30s; (b) training, starting 5 min afier the last sound, with apresentation of two electric shocks with interval between electric shocks of the 5 min and (c) test, starting 10 min afier the last shock, with 40 acoustic stimuli. The Control Group animais received no stimulation. Experiment 11I, used 1 min time intervals between (a) the end of the baseline and the trainning, (b) the two electric shocks and (c) the last electric shock and test. Experiment IV investigated the trace fear conditioning, using 2 groups: Experimental, with 3 sound shock associations; Random, with 3 shocks and 3 sounds in the random arder and Contrai, only exposed to experimental chamber. Ali the experiments used a skeleton photoperiod with 2 light pulses (15 min) to 6h (ZTOO) and 18h (ZT12) and sub-groups for each time of test: ZT02, ZT06, ZT10, ZT14, ZT18 and ZT22. In a general, the data showed that both sensitization and classical fear conditioning resulted in increases of the amplitude of sound responses with variations depending on the time of the test. Taken together, the data indicated a modulation of aversive leaming by the circadian pacemaker / Doutorado / Fisiologia / Doutor em Biologia Funcional e Molecular
64

Processos de aprendizagem e memoria aversiva em pombos : analise do envolvimento da proteina quinase C (PKC) / Aversive learning and memory processes in pigeons : analysis of involvement of protein kinase C

Dias, Elayne Vieira, 1975- 13 August 2018 (has links)
Orientador: Elenice Aparecida de Moraes Ferrari / Disertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia / Made available in DSpace on 2018-08-13T18:30:13Z (GMT). No. of bitstreams: 1 Dias_ElayneVieira_M.pdf: 1520883 bytes, checksum: 05673dcedfdc35b300eb07144edbd5bb (MD5) Previous issue date: 2008 / Resumo: O condicionamento clássico aversivo é utilizado para investigar os mecanismos celulares e moleculares na formação da memória em diferentes espécies de animais. Estes envolvem processos sinápticos que desencadeiam mecanismos de sinalização intracelular com ativação de diferentes quinases em momentos específicos. A ativação da PKC é um dos mecanismos moleculares da plasticidade sináptica subjacente à formação de memória. O presente trabalho investigou o envolvimento da PKCá/âIl no condicionamento clássico aversivo em pombos. No Experimento 1, o inibidor da PKC, calfostina C foi administrado i.c.v. em um grupo de pombos (GCdCa, n=6; 5ml de solução 60mg/ml, DMSO 2%), 1h antes do condicionamento. Outro grupo recebeu veículo (GCdVe, n=5; DMSO 2% em salina). A sessão de condicionamento teve 20 min de duração e 3 pareamentos som-choque (treino). O teste ao contexto ocorreu 24h após o treino. O Experimento 2 usou grupos de pombos expostos ao contexto experimental (GCC), som e choque não pareados (GCR) ou som-choque pareados (GCd) para investigar a ativação da PKCá/âII no hipocampo 2h após o treino, por meio de Western blot. No Experimento 3, grupos de pombos não treinados (GC, n=6) ou sacrificados em diferentes tempos após o treino - G1min (n=6), G1h (n=6), G2h (n=6) e G24h (n=6) - foram utilizados para investigar o curso temporal da ativação da PKCá/âII e da fosforilação do substrato da PKC, GAP-43, no hipocampo. Todas as sessões foram gravadas em vídeo para posterior análise dos dados comportamentais. No Experimento 1 o GCdCa teve menor expressão da resposta condicionada de congelamento (freezing) ao contexto em comparação ao GCdVe (p<0,05), indicando que a administração da calfostina C prejudicou a memória aversiva contextual. Não ocorreram diferenças significativas na ativação da PKC á/âII entre os diferentes grupos (Experimentos 2 e 3;p>0,05), mas houve maior imuno-marcação da GAP-43 fosforilada no G1min quando comparado ao GC (Experimento 3; p<0,05). Esses dados indicam o envolvimento da PKC em mecanismos de aprendizagem e memória aversiva em pombos, e sugerem que outras isoformas além da PKCá/âII podem participar desses processos. / Abstract: The classical aversive conditioning is used to investigate cellular and molecular mechanisms of memory formation in different animal species. Those mechanisms involve synaptic processes that trigger intracellular signaling with activation of different kinases at specific time points. The PKC activation is one of the molecular mechanisms of synaptic plasticity underlying memory. This study investigated the involvement of PKCá/âIl in classical aversive conditioning in pigeons. In Experiment 1, the PKC inhibitor, calphostin C was administered i.c.v. in one group of pigeons (GCdCa, n=6; 5ml solution 60mg/ml, DMSO 2%), 1h before the conditioning. Another group received vehicle (GCdVe, n=5; DMSO 2% in saline). The session of conditioning had 20 min duration and 3 tone-shock pairings (training). The test to the context occurred 24h after training. Experiment 2 investigated with Western blot analysis the PKCá/âII activation in the hippocampus 2h after the training in groups of pigeons that were exposed to unpaired (GCR) or paired (GCd) tone-shock presentations or to the experimental context only (GCC). In Experiment 3, groups of pigeons naive (GC, n=6) or sacrificed at different times after the training - G1min (n=6), G1h (n=6), G2h (n=6) and G24h (n=6) - were used to investigate the time course of the PKCá/âII activation and phosphorylation of PKC substrate, GAP-43, in the hippocampus. All sessions were video recorded for analysis of behavioral data. In Experiment 1 GcdCa had lower expression of conditioned freezing response to the context in comparison to GCdVe (p<0.05), indicating that calphostin C administration impaired contextual aversive memory. No significant differences in the PKCá/âII activation were observed among the groups (Experiments 2 and 3; p>0.05) but the immunolabeling of phosphorylated GAP-43 in G1min was higher as compared to GC (Experiment 3; p<0.05). These data indicate the involvement of PKC in mechanisms of aversive learning and memory in pigeons and suggest that other isoforms besides PKCá/âII may play a role in those processes. / Mestrado / Fisiologia / Mestre em Biologia Funcional e Molecular
65

Classical Conditioning and Immune Reactivity in Rats

Czajkowski, Laura Anne 01 May 1988 (has links)
Psychoneuroimmunology is an interdisciplinary area that examines the interaction between behavior, the central nervous system, and the immune system. Many investigations have utilized a taste aversion paradigm to examine the effects of classical conditioning on an immune response. The procedure generally consists of an animal ingesting a novel flavor, and then being made ill and immunosuppressed by injection of a pharmacological agent. The animal is provided access to that flavor at a later time. The rejection of the novel flavor on the test day is called taste aversion and the depressed antibody titer has been labeled conditioned immunosuppression. The present research was designed condition a secondary immune response and expand the evaluation of such conditioning to include both antibody titer and affinity. The Enzyme Linked Immunoassay was also introduced as the procedure of choice to quantify immune reactivity. A depression in antibody titer and affinity was found following exposure to three of four test trials. Taste aversion did not correlate with the immune response as increased consumption of the novel flavor was exhibited on the third and fourth test trial. In the second experiment, the dosage of cyclophosphamide was increased. A depression in antibody affinity was found after the third and fourth test trials, which was consistent with the results of the first experiment. Unlike the first experiment, a depression in antibody titer was not attained on test days. Although taste aversion was observed in the treatment group on three of the four test trials, it had extinguished by test four. The results support the concept of conditioned suppression of an antigen specific immune response by exposure to the taste aversion paradigm. An important contribution of the present research was the use and modification of a precise and sensitive assay for quantification of titer and affinity; the demonstration of conditioned suppression in both antibody titer and affinity; and the demonstration of conditioned immunosuppression with a single component CS.
66

Identified Interneurons of Dorsal Hippocampal Area CA1 Show Different Theta-Contingent Response Profiles During Classical Eyeblink Conditioning

Cicchese, Joseph J. 08 May 2013 (has links)
No description available.
67

Interactions between hippocampal and cerebellar theta oscillations during cerebellar theta-contingent trace eyeblink conditioning acquisition and extinction in the rabbit.

Hoffmann, Loren C. 21 April 2014 (has links)
No description available.
68

Princípios de condicionamento à luz da análise neural do estímulo antecedente / Principles of conditioning in light of the neural analysis of the antecedent stimulus

Guerra, Luiz Guilherme Gomes Cardim 20 April 2006 (has links)
A participação de estímulos e respostas em contingências não depende de sua origem interna ou externa. O ponto relevante é que a natureza funcional dos termos da contingência baseie-se em leis comportamentais. Nesse sentido, eventos neurais são também comportamentais, e assim podem permitir a observação de mecanismos básicos da aprendizagem. No presente trabalho, fez-se o exame desses mecanismos com vistas a verificar se a base neural dos paradigmas de condicionamento respondente e operante compartilha o princípio de que o reforço seleciona relações entre estímulos antecedentes e respostas. Tais relações ocorreriam devido ao fortalecimento de conexões sinápticas que vinculam os eventos de contingências. Aqui o estímulo antecedente tem importância crítica, pois a entrada sináptica para a evocação da resposta supostamente depende do sinal por ele gerado. O estímulo antecedente é sempre o evento presente no momento em que o organismo comporta-se, seja eliciando respostas reflexas, seja gerando a ocasião para a emissão de respostas operantes. Foram agrupados dados da literatura científica que propiciaram a comparação dos condicionamentos, com foco na função do estímulo antecedente. O resultado desta pesquisa abrangeu os seguintes aspectos: vias e mecanismos centrais de reforço, antecedentes neurais de resposta motora, antecedentes neurais em processos de discriminação comportamental, e plasticidade neural na aprendizagem. A literatura de bases neurais do comportamento forneceu vasto material para a análise de processos celulares e circuitos neurais envolvidos na aprendizagem, e indicou que a atividade do neurotransmissor dopamina modula o condicionamento em moluscos e mamíferos; a dopamina também atua como um sinal de discrepância comportamental nas vias neurais do reforço positivo que se dirigem a uma estrutura básica do reforço, o núcleo accumbens; neurônios corticais estão envolvidos no controle de estímulos, liberando preferencialmente glutamato pela via do estímulo antecedente, seja CS ou SD; o condicionamento respondente depende de alteração de eficácia sináptica no cerebelo de mamíferos, e não se conhece ainda se o mesmo ocorre no operante; em preparações in vivo e in vitro, verificou-se que os efeitos de ambos os condicionamentos convergem para um mesmo neurônio motor de molusco, embora tenham diferido as propriedades de plasticidade desse neurônio; eventos neurais podem participar de contingência operante como quaisquer de seus termos, e respostas neurais operantes e discriminativas podem de modo confiável preceder respostas motoras, o que sugere um indício de atividade cognitiva de mesma natureza que a atividade neural correlacionada com relações simbólicas. O presente trabalho mostrou vários casos de relações entre estímulos antecedentes e respostas no nível neural, nos quais foram verificados pontos de convergência e de divergência entre os paradigmas de condicionamento, que permitiram avançar no conhecimento do reforço. No sentido desse avanço, ainda foram propostas pesquisas julgadas pertinentes. / Stimuli and responses take part in reinforcement contingencies regardless of their internal or external locus of origin. The relevant point is that the functional nature of the contingency terms be based on behavioral laws. In that sense, neural events are also behavioral events, and as such they may allow for the observation of basic mechanisms of learning. In the present study, these mechanisms were examined in order to verify whether the neural basis of respondent and operant conditioning share the principle that reinforcement selects relationships between antecedent stimuli and responses. Such relationships presumably occur due to the strengthening of synaptic connections linking the contingency events. The antecedent stimulus is critical in this strengthening effect, since the synaptic input evoking a response is supposed to depend on that signal. The antecedent stimulus is the current event at the moment the organism is behaving, its function being either eliciting reflex responses or setting the occasion for operant responses. Scientific data that favored a comparison between the two conditioning processes were grouped together, with a focus on the antecedent stimulus function. The resulting analysis comprehended the following aspects: central pathways and mechanisms of reinforcement, neural antecedents of motor responses, neural antecedents in behavioral discrimination processes, and cellular plasticity in learning. The literature on the neural basis of behavior provided extensive material for the analysis of cellular processes and neural circuits involved in learning, indicating that the activity of the neurotransmitter dopamine modulates conditioning in molluscs and mammals; dopamine also acts as a behavioral discrepancy signal in the neural pathways of positive reinforcement, which lead to the nucleus accumbens, a basic structure in reinforcement; cortical neurons are involved in stimulus control, as they preferentially deliver glutamate through the CS or SD antecedent stimulus pathway; respondent conditioning depends on changes in synaptic efficacy in the cerebellum of mammals, and it is not known yet if the same occurs in operant processes; in vivo and in vitro mollusc preparations showed that the effects of both conditionings converge on the same motor neuron, although producing different plastic properties; neural events may enter an operant contingency as any of its terms, and operant and discriminative neural responses can reliably precede motor responses, suggesting a trace of cognitive activity of the same nature as the neural activity correlated with symbolic relations. The present study disclosed several instances of relationships between antecedent stimuli and responses at the neural level of analysis, pointing to convergent and divergent spots between the two conditioning paradigms that led to progress in the knowledge of reinforcement. In line with this progress, research proposals were advanced.
69

Saccadic latencies depend on functional relations with the environment / Les latences saccadiques dépendent de relations fonctionnelles avec leur environnement

Vullings, Cécile 20 December 2018 (has links)
Les modèles de décision conventionnels, basés sur l’utilisation du système saccadique comme modèle sensorimoteur, considèrent typiquement les temps de réaction comme un sous-produit des processus décisionnels, reflétant le temps nécessaire pour prendre une décision. Cependant, des recherches ont montré que les latences saccadiques sont deux fois plus longues que le temps de décision, ainsi que l’organisation de l’environnement affecte les latences saccadiques. Cette thèse propose une interprétation alternative des temps de réaction saccadiques (SRTs) en montrant que les distributions de latences saccadiques peuvent être altérées par leurs propres conséquences. Nous défendons l’hypothèse que les latences saccadiques dépendent de relations fonctionnelles avec leur environnement.Cette thèse a réalisé une analyse fonctionnelle des latences saccadiques. La première étude a évalué s’il était possible de choisir ses propres latences en fonction des contingences de renforcement en cours, dans le but d’explorer l’étendue du contrôle temporel des saccades. L’allocation des latences courtes et longues correspondait au renforcement relativement obtenu, démontrant un contrôle fin des SRTs. La seconde étude a évalué de manière plus approfondie l’effet de conséquences bénéfiques sur les SRTs, en utilisant le phénomène de taille-latence. La procédure de renforcement a été efficace pour manipuler le bénéfice de SRTs plus courts et pour réduire le phénomène de taille-latence. La troisième étude a démontré comment les stimuli antécédents en viennent à contrôler des temps de réaction spécifiques à l’aide d’un apprentissage opérant. Les contingences de renforcement ont induit un contrôle discriminatif des latences entre des stimuli différents. Enfin, la dernière expérience a exploré l’implication des processus d’apprentissage classique dans le contrôle par le stimulus des latences saccadiques. Cette étude pilote met en évidence l’influence de l’environnement et de l’historique d’apprentissage dans le contrôle temporel des saccades.Nos résultats soulignent l’incroyable plasticité du système saccadique, et l’étend au contrôle temporel des saccades. Cette thèse montre qu’un processus général d’apprentissage, basé sur les conséquences fonctionnelles des saccades, peut expliquer de manière parcimonieuse les changements dans les latences saccadiques. Démontrant que la latence est une dimension opérante des saccades, l’organisation de l’environnement contrôle l’organisation temporelle des saccades. / Conventional decision models, based on the saccadic system as a sensorimotor model, typically view reaction time as a byproduct of decisional processes, reflecting the time needed to make a decision. However, research has shown that saccadic latencies are twice as long as the decision time and that the organization of the environment affects saccade latencies. This thesis dissertation provides an alternative view of saccadic reaction times (SRTs) by showing that saccade latency distribution can be altered by their own consequences. We defend that saccadic latency depends on functional relations with its environment.This thesis conducted a functional analysis of saccadic latencies. The first study probed whether it is possible to choose one’s latencies depending on the reinforcement contingencies in force, in order to assess the extent of temporal control with saccades. The allocation of short and long latencies matched the relative reinforcement obtained, demonstrating a fine control of SRTs. The second study further investigated the effect of beneficial consequences on SRTs, using the size-latency phenomenon. The reinforcement procedure was effective in manipulating the benefit of shorter SRTs and reducing the size- latency phenomenon. The third experiment demonstrated how antecedent stimuli come to control specific reaction times through operant learning. Reinforcement contingencies induced discriminative control of latencies between different stimuli. Finally, the last experiment explored the involvement of classical learning processes in stimulus control of saccade latencies. This pilot study highlighted the influence of the environment and learning history in the temporal control of saccades.Our results emphasize the exquisite plasticity of the saccadic system, and extend it to the temporal control of saccades. This thesis shows that a general learning process, based on the functional consequences of saccades, can parsimoniously explain changes in saccadic latency. Demonstrating that latency is an operant dimension of saccades, the organization of the environment controls the temporal organization of saccades.
70

Sexual conditioning in the dyeing poison dart frog (Dendrobates tinctorius)

Gaalema, Diann E. 15 January 2010 (has links)
Amphibian populations worldwide are currently in decline. One approach to preventing extinction of some of the affected species is to create assurance colonies. These sustainable captive populations might some day be used to reestablish wild populations. One issue with creating assurance colonies is successful breeding; often difficulties arise when attempting to breed exotic animals in captivity. Sexual conditioning, a form of Pavlovian conditioning, has been shown to improve breeding behavior. In this project the efficacy of sexual conditioning to improve breeding behavior in the dyeing dart frog (Dendrobates tinctorius) was tested. The frogs were trained with a stimulus that was either predictive of or independent of exposure to a member of the opposite sex. The group trained with the predictive stimulus showed shorter latencies to a variety of breeding behaviors and produced more eggs than the control groups. The sexual conditioning procedure also increased expression of various breeding behaviors allowing for careful examination of calls and visual signaling within this species.

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