Seis estudantes universitários foram expostos a dois procedimentos de discriminação simples, cada um. Três deles aprenderam uma discriminação simultânea, seguida de sua respectiva reversão; e depois aprenderam uma discriminação sucessiva, também seguida de sua respectiva reversão. Os outros três participantes aprenderam uma discriminação sucessiva, seguida de sua respectiva reversão; e depois aprenderam uma discriminação simultânea, também seguida de sua respectiva reversão. Cada participante usou, durante todas as sessões experimentais, um equipamento para rastreamento do olhar, que permite gravar vídeos que mostram o campo de visão do participante com um cursor que aponta a fixação de seu olhar para cada sessão experimental. Isto permitiu calcular a duração dos intervalos de tempo de diversos eventos relacionados à fixação do olhar do participante. Os resultados mostram que todos os participantes que aprenderam a discriminação simultânea primeira exibiram fortes indícios de controle por seleção, e dois dentre estes três também exibiram indícios de posterior controle por rejeição. Os participantes que aprenderam a discriminação simultânea após a sucessiva exibem indícios de controle por rejeição desde o início, e dois deles mesmo antes do controle por seleção. / Six undergraduate students were exposed to two simple discrimination procedures each. Three learned a simultaneous discrimination, followed by its reversion; and then learned a successive discrimination, also followed by its reversion. The other three learned a successive discrimination, followed by its reversion; and then learned a simultaneous discrimination, also followed by its reversion. Each participant used, during all sessions, an eye-tracking device, which records video streamings with a cursor indicating the users eye fixation. That allowed to calculate the time intervals for events related to the participants eye fixations during the discrminations. Results show that all three participants who learned the simultaneous discrimination first exhibited strong evidence of select-control, and two of them also exhibited later strong evidence of rejectcontrol. Participants who learned the simultaneous discrimination after the successive discrimination exhibited strong evidence of reject-control since the beginning, and two of them did it even before showing evidence of select-control.

O presente trabalho analisou algumas das possíveis características do efeito da atenção intermodal entre elas: relação sinal/ruído e assincronia entre início dos estímulos (AIE) em relação ao tipo de tarefa realizada. Os Experimentos 1 e 2 mostraram que os efeitos da atenção intermodal se manifestam na presença de ruído visual externo, e que não se manifestam na ausência de ruído em uma AIE de 133 ms. No entanto, o Experimento 3 mostrou que quando a AIE é maior que a utilizada nos experimentos anteriores, o efeito intermodal se manifesta no comportamento na ausência de ruído visual externo. Finalmente, o Experimento 4 mostrou que em uma AIE curta (133 ms), e em uma tarefa de localização, o efeito intermodal se manifesta. Os resultados sugerem que o efeito atencional intermodal se manifesta na presença e na ausência de ruído visual e que o mecanismo de discriminação da frequência do alvo demora mais tempo para se completar do que o mecanismo de localização do alvo. / The current work examined the possible contribution of signal to noise ratio, the asynchrony between the onsets of the cue and the target (SOA) and the kind of task performed by the observer to the manifestation of crossmodal attentional effects. The Experiments 1 and 2 showed that crossmodal attentional effect appears when there is visual noise, but it does not appear when there is no visual noise at 133 ms SOA. The Experiment 3 showed that when the SOA is longer than 133 ms, the crossmodal attentional effect appears when there is no visual noise. The Experiment 4 showed that in a localization task, the crossmodal attentional effect appears even in a short SOA (133 ms). Taken together, the results indicate that crossmodal attentional effects appear when there is visual noise and when there is no visual noise. However, in the later condition and when the target has to be identified, the crossmodal attentional effect takes longer to appear.

Estudos demonstram que estímulos discriminativos de maiores probabilidades de reforço mantêm respostas de observação. Por sua vez, estímulos que compartilham funções discriminativas podem compor uma classe funcional de estímulos. Em vista disso, esta pesquisa investigou se estímulos que compartilhavam funções discriminativas, ao formar classes funcionais, passariam a reforçar respostas de observação. Dez adultos foram expostos a um treino discriminativo simples simultâneo com dois conjuntos de quatro estímulos cada. Na sequência, de modo a estabelecer classes funcionais, foram realizadas quatro reversões de contingências com tentativas de teste (sonda). Durante todo o procedimento, os participantes usaram um equipamento de rastreamento ocular para mensurar suas respostas de observação. Os resultados mostraram que oito participantes aprenderam as discriminações; sete participantes mostraram formação de classes funcionais com pelo menos um dos conjuntos usados; e, para um participante, não houve formação de classes. A avaliação das respostas de observação mostrou que, para quatro participantes, estímulos que compuseram em classes funcionais passaram a manter correspondentemente respostas de observação, sugerindo que, ao se estabelecerem como classes de estímulos discriminativos, os estímulos passaram a exercer funções reforçadoras condicionadas para respostas de observação. Dessa forma, classes de estímulos discriminativos constituem-se, também, como classes de reforçadores condicionados / Studies have demonstrated that discriminative stimuli paired with high probabilities of reinforcement maintain observing responses in a higher rate than those stimuli paired with low probabilities of reinforcement or extinction. On the other hand, stimuli that share discriminative functions may become a functional stimulus-class. Considering this, the present research evaluated whether stimuli that share discriminative functions by becoming a functional class would also acquire a reinforcing function for observing responses. Ten adults were submitted to a simple simultaneous discriminative training with two sets of four stimuli each. Then, to establish functional classes, four contingency reversals with test trials were conducted. Throughout the procedure, participants observing responses were measured with an eye-tracker device. Eight participants learned the discriminations. Seven participants showed evidence of functional class formation for at least one of the sets used, and one participant showed no evidence of functional class formation. Observing measures showed that the stimulus-set that became functional classes for four participants also maintained their observing responses. These data suggest that, when a set of stimuli becomes a discriminative stimulus-class, the stimuli in the set acquire conditioned reinforcement functions for observing responses. This evidence suggests that discriminative stimulus-classes are classes of conditioned reinforcers

Identifying the causes and consequences of intra-specific variation in cognitive abilities is fundamental to our understanding of the evolution of cognition. The social environment and cognitive abilities appear inextricably linked, yet evidence for how the social environment affects cognitive performances and further, how cognitive performances influence the social environment, has seldom been explored. Using the pheasant, Phasianus colchicus, I explore the relationships between individual variation in cognitive performances in relation to broad and fine-scale structure of the social environment and endeavour to separate cause and consequence. I demonstrate a positive causal effect of the broad-scale social environment on cognitive performances by observing increases in the accuracy of spatial discrimination performances when individuals are in larger groups (Chapter Two and Chapter Four). I show that the positive effects of larger group size occur over a relatively short period (less than one week), suggesting that cognitive performances are flexible in response to the social environment and I suggest four potential mechanisms. I show that while males are part of a social hierarchy, spatial discrimination performances are related to this fine-scale social structure and higher-ranking males outperform lower ranking males (Chapter Three). When attempting to determine cause and consequence, I found that spatial learning performances early in life did not predict adult cognitive performances on the same task or predict their adult social rank (Chapter Four). Hence, my results do not support that social rank is a consequence of spatial learning abilities in male pheasants. The relationship between spatial learning performances and social rank was found in adult males that had their social rank artificially elevated, suggesting that cognitive performances were not simply the result of the current social environment but remain closely related to past agonistic relationships. I did not find a relationship between early life aggression with performances on either a spatial or a non-spatial task in females or males (Chapter Five). This highlights the importance of investigating early life relationships and suggests that the relationship between spatial learning and aggression in adult males may become associated over time as a consequence of further spatial learning experiences, and, or, aggressive interactions. I then demonstrate a consequence of individual variation in cognitive abilities and show that adult foraging associations in the wild disassort by early life cognitive performances (Chapter Six). Individuals with good inhibitory control performance and poor visual discrimination performances were more central in social networks. I propose that differences in cognitive abilities manifest in foraging strategy and influence the resulting social structure. The implications of this predictable social structure remain to be explored. Finally, I discuss these results and how they contribute to our understanding of how the social environment causes individual differences in cognitive performances, as well as how variation in cognitive performances may shape the social environment. I suggest the potential implications of these findings and ideas for future work.

Thesis (Ph. D.)--Miami University, Dept. of Psychology, 2008. / Title from second page of PDF document. Includes bibliographical references (p. 60-67).

Made available in DSpace on 2014-12-17T15:37:05Z (GMT). No. of bitstreams: 1 TaulliBL_DISSERT.pdf: 1150500 bytes, checksum: b3e29a8f79cd73bc29681007aa790d27 (MD5) Previous issue date: 2011-09-27 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The discrimination learning is assessed through instrumental tasks in which the individual is rewarded for choosing one item over another. Thus, in concurrent visual discrimination of objects the animal must learn that only one of the objects will be rewarded. The concurrent visual discrimination is relatively simple, and already been observed Callithrix jacchus is able to accomplish this task. As yet wasn't seen the influence of the qualitative aspects of the rewards, in the performance of concurrent visual discrimination of objects in nonhuman primates, and as in most tests are used isolated animals, the present study had two stages: at first we had as objective to analyze the influence of the caloric value of the reward on the performance in concurrent visual discrimination of objects in isolated animals; in the second, we had the intention analyze performance of C. jacchus in realization of discrimination task in different social contexts, as well as, analyze the influence of previous experience in task performance. In the first stage (Study 1), the animals were not able to discriminate foods that presented small caloric differences . This incapacity in discriminates the rewards was responsible by generating randomness in task of concurrent visual discrimination of objects. In the second stage (Study 2), observed that, independent of social context in which the task was presented, the performance both of the experienced animals as the inexperienced animals tended to randomness. In the first case, is likely that the pattern of responses of the experienced animals is a reflection of their own performance when they were observed in isolation. In the second case, in turn, the randomness was probably due to the small number of sessions. Although present a pattern of performance similar to inexperienced individuals, we verify that the experienced animals monopolize the food consumption when they were in the presence of inexperienced individuals. This was a consequence of the experienced animals have presented lower latency the approximation of apparatus and, consequently, obtain more food. In turn, the inexperienced animals, when were in the presence of experienced, had to adopt alternative strategies to obtain food. Thus, C. jacchus is able to use the previous information he had about the task of solving their own benefit. / A aprendizagem discriminat?ria ? analisada atrav?s de tarefas instrumentais nas quais o indiv?duo ? recompensado por escolher um item ao inv?s de outro. Desse modo, na discrimina??o visual simult?nea de objetos o animal deve aprender que somente um dos objetos ser? recompensado. A discrimina??o visual simult?nea ? relativamente simples, e j? foi observado que Callithrix jacchus ? capaz de realizar essa tarefa. Como ainda n?o foi verificada a influ?ncia dos aspectos qualitativos das recompensas no desempenho da discrimina??o visual simult?nea de objetos em primatas n?o-humanos, e como na maioria dos testes s?o utilizados animais isolados, o presente trabalho apresentou duas etapas: na primeira tivemos como objetivo analisar a influ?ncia do valor cal?rico da recompensa sobre o desempenho na discrimina??o visual simult?nea de objetos em animais isolados; na segunda, tivemos o intuito analisar o desempenho de C. jacchus na realiza??o da tarefa discriminat?ria em diferentes contextos sociais, assim como, analisar a influ?ncia da experi?ncia anterior no desempenho da tarefa. Na primeira etapa (Estudo 1), os animais n?o foram capazes de discriminar os alimentos que apresentavam pequenas diferen?as cal?ricas. Essa incapacidade em discriminar as recompensas foi respons?vel por gerar aleatoriedade na tarefa de discrimina??o visual simult?nea de objetos. Na segunda etapa (Estudo 2), observamos que, independente do contexto social no qual a tarefa foi apresentada, o desempenho tanto dos animais experientes quanto dos animais inexperientes tendeu a aleatoriedade. No primeiro caso, ? prov?vel que o padr?o de respostas dos animais experientes seja um reflexo do seu pr?prio desempenho quando foram observados isoladamente. No segundo caso, por sua vez, a aleatoriedade foi devida provavelmente ao pequeno n?mero de sess?es. Apesar de apresentar padr?o de desempenho semelhante aos indiv?duos inexperientes, n?s verificamos que os animais experientes monopolizaram o consumo do alimento quando estavam na presen?a de indiv?duos inexperientes. Isso foi uma consequ?ncia dos animais experientes terem apresentado menor lat?ncia de aproxima??o do aparato e, consequentemente, obterem mais alimento. Por sua vez, os animais inexperientes, quando estavam na presen?a de experientes, tiveram que adotar estrat?gias alternativas para obter o alimento. Desse modo, C. jacchus ? capaz de utilizar a informa??o anterior que tinha sobre a resolu??o da tarefa em benef?cio pr?prio.

Estudos demonstram que estímulos discriminativos de maiores probabilidades de reforço mantêm respostas de observação. Por sua vez, estímulos que compartilham funções discriminativas podem compor uma classe funcional de estímulos. Em vista disso, esta pesquisa investigou se estímulos que compartilhavam funções discriminativas, ao formar classes funcionais, passariam a reforçar respostas de observação. Dez adultos foram expostos a um treino discriminativo simples simultâneo com dois conjuntos de quatro estímulos cada. Na sequência, de modo a estabelecer classes funcionais, foram realizadas quatro reversões de contingências com tentativas de teste (sonda). Durante todo o procedimento, os participantes usaram um equipamento de rastreamento ocular para mensurar suas respostas de observação. Os resultados mostraram que oito participantes aprenderam as discriminações; sete participantes mostraram formação de classes funcionais com pelo menos um dos conjuntos usados; e, para um participante, não houve formação de classes. A avaliação das respostas de observação mostrou que, para quatro participantes, estímulos que compuseram em classes funcionais passaram a manter correspondentemente respostas de observação, sugerindo que, ao se estabelecerem como classes de estímulos discriminativos, os estímulos passaram a exercer funções reforçadoras condicionadas para respostas de observação. Dessa forma, classes de estímulos discriminativos constituem-se, também, como classes de reforçadores condicionados / Studies have demonstrated that discriminative stimuli paired with high probabilities of reinforcement maintain observing responses in a higher rate than those stimuli paired with low probabilities of reinforcement or extinction. On the other hand, stimuli that share discriminative functions may become a functional stimulus-class. Considering this, the present research evaluated whether stimuli that share discriminative functions by becoming a functional class would also acquire a reinforcing function for observing responses. Ten adults were submitted to a simple simultaneous discriminative training with two sets of four stimuli each. Then, to establish functional classes, four contingency reversals with test trials were conducted. Throughout the procedure, participants observing responses were measured with an eye-tracker device. Eight participants learned the discriminations. Seven participants showed evidence of functional class formation for at least one of the sets used, and one participant showed no evidence of functional class formation. Observing measures showed that the stimulus-set that became functional classes for four participants also maintained their observing responses. These data suggest that, when a set of stimuli becomes a discriminative stimulus-class, the stimuli in the set acquire conditioned reinforcement functions for observing responses. This evidence suggests that discriminative stimulus-classes are classes of conditioned reinforcers

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

The purpose of this study was to evaluate the effects of a training package consisting of response restriction and the reinforcement of self-evaluation on letter reversal errors. Participants were 3 typically developing boys between the age of 5 and 7. The results indicated that the training package was successful in correcting reversals in the absence of a model during training and on application tests. These improvements maintained during subsequent follow-up sessions and generalized across trainers. Fading was not always necessary in correcting reversals, but was effective in correcting reversals that persisted during the overlay training procedures. The advantages to implementing a systematic intervention for reducing letter reversal errors in the classroom, as well as directions for future research, are discussed.

<p>  </p> <p><em>Syngap1+/-</em> is a mouse mode for intellectual disability and autism spectrum disorder where haploinsufficiency of the <em>Syngap1</em> gene and therefore downregulation of SynGAP1 leads to early maturation of synapses within the brain within post-natal days fourteen and sixteen instead of at the normal developmental schedule of post-natal day thirty. This early-shifted timeline falls directly before the visual critical where binocular matching between inputs from the two eyes occurs, and during a period where neurons become selective to specific orientations. High-level visual and cognitive issues observed in autism spectrum disorder patients might follow from deficits in basic sensory processing development, but it is not yet understand how <em>Syngap1</em> haploinsufficiency affects visual development and visual processing. Therefore, to characterize visual processing within the <em>Syngap1+/-</em> mouse model of autism spectrum disorder, acute electrophysiological recordings were performed within the monocular and binocular regions of the mouse visual cortex (V1). Responses to a series of visual stimuli were analyzed to measure and compare receptive field size, orientation selectivity, and binocularity between <em>Syngap1+/-</em> mice and littermate controls. In order to understand how potential deficits in physiology could translate into visual perception, a behavioral training protocol was implemented which isolated visual acuity in mice. In accordance with known developmental timelines in the visual cortex, it was found that the receptive field sizes of V1 neurons in <em>Syngap1+/-</em> mice were unchanged from wild type controls. However, these same neurons had wider tuning curves and lower firing rates than neurons in littermate controls. Ocular dominance was unaltered between <em>Syngap1+/-</em> and wild type mice, but this was possibly due to low sample sizes of neurons from the binocular regions of V1. At the behavioral level, lower visual acuities were discovered in <em>Syngap1+/-</em> mice with a size degree difference compared to littermate controls – a minor but significant difference. These results indicate a reduction in SynGAP1 expression has a perceivable effect on V1 development and function at both physiological and behavioral levels.</p>