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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.
121

Assessing the Stimulus Control of Observers.

Kuhn, Robin Merritt 12 1900 (has links)
The science of behavior analysis relies heavily on direct observation. Human observers are typically used to measure behavior in applied settings. Although the use of human observers is beneficial in many regards, it also presents challenges. Of primary concern is the extent to which the data generated by observers actually corresponds to the behavioral events of interest, and the implications this may have in terms of replication. This study assessed the effects that labels, definitions, and examples and non-examples of two different modalities had on observer accuracy, consistency, and agreement. Results showed that current practices in observer training may require refinement to ensure high observer accuracy, consistency, and agreement. Suggestions for how to improve the desired stimulus control of observers are provided.
122

Does Stimulus Complexity Affect Acquisition of Conditional Discriminations and the Emergence of Derived Relations?

Martin, Tiffani L. 12 1900 (has links)
Despite the central importance of conditional discriminations to the derivation of equivalence relations, there is little research relating the dynamics of conditional discrimination learning to the derivation of equivalence relations. Prior research has shown that conditional discriminations with simple sample and comparison stimuli are acquired faster than conditional discriminations with complex sample and comparison stimuli. This study attempted to replicate these earlier results and extend them by attempting to relate conditional discrimination learning to equivalence relations. Each of four adult humans learned four, four-choice conditional discriminations (simple-simple, simple-complex, complex-simple, and complex-complex) and were tested to see if equivalence relations had developed. The results confirm earlier findings showing acquisition to be facilitated with simple stimuli and retarded with complex stimuli. There was no difference in outcomes on equivalence tests, however. The results are in implicit agreement with Sidman's theory of stimulus equivalence.
123

The Effect of a Brief Acceptance-Based Protocol on Health Related Relational Framing

Madrigal-Bauguss, Jessica A. 08 1900 (has links)
Behavior analysts who study verbal behavior theorize that people derive relationships between stimuli - forming stimulus classes such that psychological functions transfer among stimuli and therefore affect behavior. Verbal processes are thought to play a role in cancer patients' behavioral flexibility. The current study examined if an analogue intervention produced changes in relations between health-relevant stimuli from pre- to post-test in patient and student samples. A matching-to-sample (MTS) task required participants to form three 4-member classes that included health, treatment, or neutral terms. Participants next listened to either an acceptance-based or a control-based rationale and therapy exercise, or a distracter task. Then, they were re-exposed to the MTS task. Latencies and accuracies for learning each class as well as between condition differences were examined. Finally, changes in ratings of stimuli from pre to post analogues were measured. Differences in stimuli ratings were seen in the student sample, reflecting transfer of function and some reduction in responsiveness to stimuli following intervention, but overall no learning performances are found. Discussion explores the consistency of the findings with acceptance and commitment therapy (ACT) theory in light of the seemingly lack of findings.
124

On the Further Exploration of Interactions between Equivalence Classes and Analytic Units

Stancato, Stefanie S. 05 1900 (has links)
Sidman's (2000) theory of stimulus equivalence predicts an interaction between the development of analytic units and the development of equivalence relations. Previous research has documented these interactions (stewart, Barnes-Holmes, Roche, & Smeets, 2002; Vaidya & Brackney, 2014), therefore the current study attempted to replicate the effects seen in Vaidya & Brackney, 2014 (Experiment 2). Baseline conditional discriminations were trained for two sets of three, three-member classes, while participants simply observed stimuli in the third set which was arranged identical to those of Sets 1 and 2. Following equivalence tests where performance met the accuracy criterion of 85% for Sets 1 and 2, participants then entered a simple successive discrimination training phase where common responses were then trained with an equivalence class (pressing the Q key in the presence of A1, B1, or C1), cross equivalence classes (pressing the R key in the presence of A4, A5, or A6), or for stimuli where the participants had experience with them, but the contingencies were never arranged to facilitate equivalence class formation. Results showed a facilitative effect for common responses drawn from within equivalence classes (Set 1), and a retardation effect for common responses drawn from across equivalence classes (Set 2), for three of the five participants. Results for Set 3 showed an acquisition that fell intermediate to that of Sets 1 and 2, respectively, suggesting an interaction occurring between existing equivalence relations and the development of analytic units.
125

Effects of Brief Persistence Training on the Cue Discrimination Task Performance of Externally and Internally Controlled Elementary School Students

Cox, Dan Murchison 12 1900 (has links)
The problem with which this investigation is concerned is one of increasing the goal-striving and achievement behavior of externally controlled students. The present study was designed to test the efficacy of short-term persistence training. The purpose of the training was to alter temporarily the cue discrimination and paired-associate memory task outcomes of externally controlled students. It was found that persistence training had no significant effect on either the cue discrimination or paired associate memory task performance of the students. Surprisingly, internals failed to do better than externals, regardless of the type of persistence training or the task employed. Although the total internal IARQ scores of the students in this study were comparable to those of the standardized norm of the IARQ, the students did not perform as might have been expected from the review of the literature. Because persistence training failed to enhance the students' cue discrimination or paired-associate memory task performance, it was concluded that brief persistence training was ineffective. However, because externals performed comparably to internals it was also concluded that the locus of control dimension was not predictive of achievement on these tasks for these students. This finding was in opposition to most related literature. Further research was therefore recommended comparing the performance of bright, high achieving externals (like those in the present investigation) with that of more typical external students (e.g. public school externals).
126

LEARNING TO DISCRIMINATE TERRORISTS: THE EFFECTS OF EMOTIONAL INTELLIGENCE AND EMOTIVE CUES

FELLNER, ANGELA N. 17 July 2006 (has links)
No description available.
127

A Comparison of Auditory and Visual Stimuli in a Delayed Matching to Sample Procedure with Adult Humans.

DeFulio, Anthony L. 12 1900 (has links)
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.
128

Efeito de diferentes treinos de discriminação sobre as fixações dos olhos de humanos / The effect of different discrimination trainings on human fixations of the human eye

Pessoa, Candido Vinicius Bocaiuva Barnsley 18 October 2010 (has links)
O estudo das fixações e dos movimentos dos olhos pode trazer contribuições para o entendimento do estabelecimento do controle de estímulos discriminativos. O objetivo desta pesquisa foi verificar se análises mais moleculares das durações e frequências das fixações dos olhos de humanos em direção a estímulos antecedentes em diferentes treinos de discriminação fornecem resultados mais sistemáticos sobre estas fixações do que os resultados obtidos até o presente momento. Foram realizados 3 experimentos com 4 fases cada um. Os participantes foram jovens com idades entre 16 e 27 anos. Cada participante foi submetido a uma sessão experimental individual. Nos treinos de discriminação, 2 conjuntos de 80 imagens que não se repetiram ao longo do treino foram utilizados como estímulos antecedentes. As respostas a serem controladas discriminativamente foram pressões na barra de espaço de um teclado de computador e as consequências diferenciais programadas para estas respostas foram apresentação de um som (plim) e apresentação de pontos. O Experimento 1 contou com 4 participantes. Na 1ª fase, pressionar a barra de espaço diante de estímulos dos 2 conjuntos não teve consequências programadas. Na segunda fase, os sons foram apresentados contingentes a pressões na barra em esquema de intervalo variável de 3 s (VI-3 s) apenas diante dos estímulos de um dos conjuntos (componentes de reforço). Não houve consequências programadas para pressões na barra diante dos estímulos do segundo conjunto nessa fase (componentes de extinção). Na 3ª fase, as contingências de reforço e extinção foram revertidas em relação aos conjuntos de estímulos antecedentes. Na 4ª fase, pressões à barra diante de estímulos de ambos os conjuntos podiam produzir o som e os pontos em VI-3 s. Ao final da sessão, o participante foi informado de quantos pontos recebeu. No Experimento 2, com 4 participantes, o componente de extinção foi substituído por um componente em que pressões na barra tinham como consequência, em VI-3 s, um som diferente, indicativo de perda de pontos. O Experimento 3, com 3 participantes, foi análogo ao primeiro, com a exceção de que, durante a 2ª e 3ª fases, pressões na barra durante os últimos 2 segundos dos componentes de extinção postergaram a mudança para o próximo componente. Durante todo o experimento foram registrados os movimentos dos olhos dos participantes, as pressões na barra de espaço e recebimento de pontos. RESULTADOS: No Experimento 1, para os 4 participantes, nas 2ª e 3ª fases, as durações das primeiras fixações nos estímulos relacionados ao reforço foram mais longas do que as fixações nos estímulos relacionados à extinção. Este resultado não foram replicados nos Experimentos 2 e 3. Esta análise mais molecular apresentou sistematicidade maior de resultados que análises anteriores / Eye movements and fixation may contribute for understanding the establishment of discrimination learning. The present research investigated whether more molecular analysis than the ones made so far of frequency and duration of eye fixation to antecedent stimuli during discrimination training may result in systematic data. Three experiments were conducted, each one with 4 different phases. Participants were humans from 16 to 27 years old. Each participant was submitted to only one individual experimental session of about 12 minutes. On discrimination trainings, a set of 80, non-repeating, abstract images and a set of 80, non-repeating, figurative images were used as antecedent stimuli. Responses to be controlled were computer keyboard space-bar pressings and differential consequences were a sound (plin) presentation and delivery of points. Experiment 1 counted with 4 participants. On Phase 1 space-bar pressing had no differential consequences. On Phase 2 sound was presented contingent upon space-bar pressing on a variable interval of 3 s schedule (VI 3-s) during display of only one set of images (reinforcing components). No consequences were programmed for space-bar pressings during display of the alternative set (extinction components). On Phase 3 reinforcement and extinction contingencies were reversed in relation to antecedent stimuli sets. On Phase 4 space-bar pressing during display of both sets of stimuli were reinforced with sound and points on VI 3-s. The amount of points received was only informed for the participant at the end of the session. Experiment 2 counted with 4 participants and the same 4 phases. The extinction components were exchanged for components in which points indicated by a second kind of sound (bee) were withdraw contingent to space-bar pressing on a VI 3-s schedule. Experiment 3 counted with 3 participants and the same 4 phases. On this experiment termination of extinction components was contingent on 2 s without space-bar pressings. Eye fixation, space-bar pressing, and sound delivery were registered during the entire sessions for the 3 experiments. Duration of the first fixation on antecedent stimulus was longer for reinforcement components than for extinction components during Phases 2 and 3 for the 4 participants of Experiment 1. These results were not replicated for Experiments 2 and 3. The more molecular analysis resulted in a more systematic data of human eye fixation
129

Training of spider monkeys in a food-rewarded two-choice olfactory discrimination paradigm and assessment of olfactory learning and memory performance

Aineslahti, Emmi January 2019 (has links)
There is little knowledge about olfactory learning in primates, even though primates are known to use olfaction in several behaviors including food selection and territorial defense. Therefore I assessed the olfactory learning and memory performance in five adult spider monkeys (Ateles geoffroyi) using a food-rewarded two-choice olfactory discrimination paradigm. The spider monkeys acquired the initial odor discrimination in 530-1102 trials and in a series of intramodal transfer tasks they needed 30-510 trials to reach the learning criterion. There was a significant negative correlation between the number of trials needed to reach the learning criterion and the number of transfer tasks completed. Thus, as a group, the animals displayed olfactory learning set formation. The number of trials that the spider monkeys needed in initial olfactory learning was comparable to that of other primate species tested previously but higher compared to that of other mammals such as dogs and rats. The learning speed of the spider monkeys in intramodal transfer tasks was similar to that of other mammals tested, suggesting that primates are less prepared to use olfactory cues in the initial solving of a problem but that once they learn the concept, their learning speed with novel odor discrimination problems is not generally slower than that of non-primate mammals. All spider monkeys tested reached the learning criterion in the memory tasks straight on the first testing day, that is: within 30 trials, suggesting similar long-term odor memory capabilities in spider monkeys and other mammals such as dogs, mice and rats.
130

Investigação longitudinal dos efeitos de diferentes contingências com estímulos apetitivos e aversivos sobre o desamparo aprendido / Longitudinal research on the effects of different contingencies with appetitive and aversive stimuli upon learned helplessness

Emileane Costa Assis de Oliveira 12 December 2007 (has links)
A hipótese do desamparo aprendido foi apresentada por Seligman & Maier em 1976 com uma suposta generalidade para todas as condições de estímulo, aversivos ou não e também como um modelo explicativo para a depressão humana. Esta proposição permitiu algumas manipulações experimentais no sentido de reverter o efeito do desamparo, utilizando, inclusive, reforçamento positivo na fase de \"terapia\". A partir dessas questões, o presente trabalho investigou: (a) se animais que apresentaram desamparo em teste de fuga também apresentam dificuldade de aprendizagem reforçada positivamente, envolvendo ou não controle de estímulos; (b) se a exposição ao reforço positivo elimina o desamparo e (c) se o desamparo interfere na resistência à mudança, medida sobre uma segunda aprendizagem discriminativa, reforçada positivamente, que envolve inversão do controle de estímulos. Ratos foram expostos a choques controláveis (C), incontroláveis (I) ou nenhum choque (N), e posteriormente submetidos ao teste de fuga. Foram selecionados três grupos (n=4) de animais que apresentaram desamparo (grupo I) ou aprendizagem de fuga no teste (grupos C e N). Em seguida, todos foram submetidos a (1) reforçamento positivo da resposta de pressão à barra (modelagem, CRF e 10 sessões de treino discriminativo FR/extinção), (2) re-teste de fuga, (3) 10 sessões de treino discriminativo com inversão dos estímulos sinalizadores. Outros quatro animais receberam apenas as sessões de reforçamento positivo. Obteve-se que todos os sujeitos aprenderam igualmente a discriminação e sua reversão, e que 3/4 dos animais do grupo I mantiveram o desamparo no segundo teste de fuga. Esses resultados indicam que o desamparo não se generalizou para a aprendizagem reforçada positivamente e que a exposição ao reforçamento positivo não aboliu o desamparo para a maioria dos sujeitos. Os dados foram discutidos considerando-se o efeito seletivo do desamparo, que ocorre apenas frente a algumas contingências, mas não a todas. Quanto ao fato da \"terapia\" com reforço positivo não ter modificado a dificuldade de aprender uma resposta mediante reforçamento negativo isso sugere que, se o desamparo decorre da aprendizagem de impossibilidade de controle sobre o ambiente, essa aprendizagem não abrange todos os estímulos do ambiente de forma generalizada, mas apenas a uma (ou algumas) determinada classe de estímulos. A identificação das características que definem essa(s) classe (ser choque, ser aversivo ou outras) também deve ser objeto de futuras investigações. / The learned helplessness hypothesis was put forward by Seligman & Maier in 1976 under the assumption of generality among all stimulus conditions, aversive or otherwise, and as an explanatory model of human depression. This proposition allowed for some experimental manipulations aimed at reversing the effect, using, among others things, positive reinforcement during a \"therapy\" phase. With that in mind, the present research attempted to investigate whether: (a) animals that showed signs of helplessness in an escape test also show a learning deficit with positive reinforcement, whether or not involving stimulus control; (b) the exposure to positive reinforcement may cancel out helplessness and (c) helplessness interferes with resistance to change, measured during a second, positively reinforced, discrimination learning (reversal). Rats were first exposed to controllable (C), uncontrollable (I) or no shocks (N) and then to an escape test. Three groups (n=4) were selected: one that displayed helplessness (group I) and two that learned to escape (groups C and N). After that, all subjects were exposed to (1) positive reinforcement of lever pressing (shaping, CRF and ten sessions of discrimination between FR and extinction), (2) the same escape test, (3) ten sessions of discrimination learning with reversed discriminative stimuli. Other four animals were exposed only to sessions of positive reinforcement. All animals learned discrimination and reversal, and three out of four animals of group I remained helplessness in the second escape test. These results suggest that helplessness did not generalize to a positively reinforced task and that exposure to positive reinforcement did not cancel out helplessness for most subjects. Results are discussed considering the selective effect of helplessness, which occurs under some conditions, but not under all. The fact that therapy with positive reinforcement did not reduce the learning deficit observed with negative reinforcement suggest that if helplessness result from learning that it is impossible to control the environment, this knowledge does not include all stimuli in a generalized manner, but only one (or some) certain stimuli class. The identification of the characteristics that define these classes (electric shocks, aversive stimuli, among others) should also be the purpose of future research.

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