No description available.

No description available.

The purpose of this experiment was to compare the effects of combining negative reinforcement and positive reinforcement during teaching with the effects of using positive reinforcement alone. A behavior was trained under two stimulus conditions and procedures. One method involved presenting the cue ven and reinforcing successive approximations to the target behavior. The other method involved presenting the cue punir, physically prompting the target behavior by pulling the leash, and delivering a reinforcer. Three other behaviors were trained using the two cues contingent on their occurrence. The results suggest that stimuli associated with both a positive reinforcer and an aversive stimulus produce a different dynamic than a situation that uses positive reinforcement or punishment alone.

This study attempted to reduce three response classes in the verbal behavior of a forty-three-year-old female graduate student. Consequences were placed on interruptions, illogical statements, and total time talking. Specifically, a response rate was taken on the three response classes, and contingent money withdrawal for exceeding defined limits was used as punishment. The treatment was generally effective in reducing interruptions, illogical statements, and total time talking to one half the baseline level, but the follow-up phase suggests that some form of maintainance procedure would be needed to maintain the rate at the lower level.

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.

Pesquisas sobre interação entre contingências de treino Pavloviano (PV) e treino operante (OP) têm enfatizado a influência do treino Pavloviano sobre o responder operante, mas não uma interação entre ambos os tipos de condicionamento. Neste trabalho é proposto estudar a interação a partir da combinação dos estímulos de ambas as contingências de treino, de forma que eles atuem simultaneamente como variáveis independentes na produção de um fenômeno comportamental. Para isso, a manipulação da taxa de reforço correlacionada aos estímulos condicional (CS) e discriminativo (SD) e a combinação desses estímulos em procedimentos de discriminação com estímulo composto foram utilizados como estratégias experimentais. No Estudo 1, três experimentos foram realizados com o objetivo de verificar a relação linear entre a taxa de reforço (r) correlacionada aos estímulos e a taxa de resposta (R) em treinos de discriminação com estímulos compostos em ratos. Nos Experimentos 1 (treino PV) e 2 (treino OP), ratos passaram por treino com um estímulo composto AB100% e três estímulos elementais, B50%, C50% e D25%. No Experimento 1 uma solução aquosa de sacarose (SAC) era liberada, como estímulo incondicional (US), em 100% das tentativas de AB100%, em 50% das vezes em B50% e C50% e em 25% das tentativas com D25%, em esquema de tempo variável VT-10s. No Experimento 2 a mesma taxa de SAC correlacionada aos estímulos foi mantida, mas dependeu do responder em esquema variável VI-10 s. Após essa fase, em ambos os experimentos, tentativas de sonda com o estímulo A, em extinção, foi adicionada. As respostas avaliadas foram inserir a cabeça no bebedouro (RIC) no treino PV (Experimento 1) e pressão à barra (RPB) no OP (Experimento 2). No experimento 3, a r na presença do estímulo A100% foi 100% e de B50% e C50% foi 50%. O estímulo avaliado em sonda foi um composto BC. Os resultados dos Experimentos 1 e 2 mostraram que a R da Sonda A foi equivalente à R nos estímulos B50% e C50%, indicando uma relação linear entre r e R (i.e., rA = rAB-rB). No Experimento 3, a R na Sonda BC foi equivalente à R em A100%, indicando somação das taxas de reforço (i.e., rBC = rB + rC). Nos experimentos 4 e 5 (Estudo 2) os treinos PV e OP foram combinados. Ratos passaram por PV e OP na mesma sessão, como o objetivo de verificar a somação da taxa de reforço (i.e., US e Sr) a partir da combinação de CS e SD em condicionamento com estímulo composto. Nas tentativas de OP, RPB em VI-10 s foi seguido por SAC em 100% das vezes nas tentativas com o estímulo A100% e em 50% das vezes em C50%. Nas tentativas de treino PV, o estímulo B50% foi seguido por SAC em 50% das vezes, em VT-10s, com a barra ausente. Após essa fase, os estímulos B50% e um composto BC foram adicionados ao treino por dez sessões, mas apresentados em tentativas de sonda em extinção (Exp. 4); no Experimento 5, foram realizadas sete sessões apenas com a Sonda BC e mais quatro sessões com as Sondas B e BC. Os resultados do experimento 4 indicaram somação entre os estímulos B e C em relação à resposta RIC (R em Sonda BC equivalente à R em A100%), mas não para RPB. No experimento 5, houve ocorrência de somação entre os estímulos B e C em ambos os tipos de treino (R em BC foi equivalente à R em A100%, para ambas as respostas RIC e RPB). Os dados foram discutidos em termos da teoria da estimação da taxa (RET), somação da taxa de reforço envolvendo CS e SD combinados e valor preditivo dos estímulos durante o condicionamento / Researches on Pavlovian-operant training interaction have emphasized the influence of Pavlovian training on the operant responding, but not an interaction between both type of conditioning. In this work, it is proposed to study the interaction through the combination of the stimuli of both training contingencies, so that they act simultaneously as independent variables in the production of a behavioral phenomenon. For this, the manipulation of the reinforcement rate correlated to the conditional (CS) and discriminative (SD) stimuli, and the combination of these stimuli in the procedure of discrimination with compound stimulus were used as experimental strategies. In study1, three previous experiments were carried out with the objective of verifying the linear relationship between the reinforcement rate (r) correlated to stimuli and rate response (R) on compound stimulus discrimination in rats. In Experiments 1 (PV training) and 2 (OP training), rats were trained with a compound stimulus AB100% and three individual stimuli B50%, C50%, and D25%. In PV, the aqueous solution of sucrose (SUC) was delivered as the unconditional stimulus on 100% of trials with AB100%, 50% of times in B50%, and C50% and 25% of trials with D25%, on a variable time schedule VT-10 s. In the OP, the same SAC rate correlated to the stimuli was maintained but depended on the responding on a variable schedule VI-10 s. After this phase, in both experiments, probe trials with the stimulus A, in extinction, was added to each experimental session. The evaluated responses were a head entry (HE) in the PV training and lever pressing (LP) in OP training. In Experiment 3, rats received a similar training to Experiment 2, the stimulus A100% with r of 100% of trials, B50% and C50% with r of 50%. The probe stimulus was a compound BC. The results of Experiments 1 and 2 showed that R of Probe A was equivalent to R in B50% and C50% stimuli, indicating a linear relationship between r and R (i.e., rA = rAB-rB). In Experiment 3 (OP), R in Probe BC was equivalent to R in A100%, indicating summation of the reinforcement rates (i.e., rBC = rB + rC). The Experiments 4 and 5 (Study 2) were carried out with the combination of PV and OP training. Rats were trained in PV and OP procedures in the same session with the objective of verifying summation of reinforcement rates (i.e., US, and Sr) from the combination of CS and SD in conditioning with the compound stimuli. Rats were trained in PV and OP procedures in the same session, with the objective of verifying the summation of the reinforcement rate (i.e., US and Sr) from the combination of CS and SD in compound stimulus conditioning. In OP trials, LP on a VI-10s were followed by SUC on 100% of times in the A100% trials, and 50% of trials with C50%. In PV trials, the stimulus B50% was followed by SUC on 50% of trials on VT-10 s, without the lever. After this phase, B50% stimuli and a BC compound were added in OP contingency for ten sessions, in extinction (Exp 4); in Experiment 5, seven sessions were performed with only the Probe BC and four sessions with Probes BC and B. The results of Experiment 4 indicated evidence for summation in relation to HE (R in BC probe equivalent to R in A100%), but not for LP. In Experiment 5, there was the occurrence of summation in both types of training (R in BC was equivalent to R in A100%, for both HE and LP responses). The data were discussed in terms of Rate Estimation Theory (RET), the summation of the reinforcement rate involving combined CS and SD, and the predictive value of the stimuli during conditioning

The problem of this study was to determine the differences on selected variables between who prefer a lecture-test learning approach and those who prefer a lecture-contingency management learning approach after experience with both learning systems in an introductory psychology course. The purposes were 1) to compare personality characteristics of self-concept and reward expectancies between students who select a lecture-contingency management and those who select a lecture-test learning approach; 2) to determine the effect on academic achievement of preference for a lecture-contingency management versus a lecture-test learning approach; and 3) to compare age, grade point average, and previous instructional experience between students who choose a lecture-contingency management and those who choose a lecture-test learning approach after experience with both approaches of students in an introductory psychology course in a metropolitan community college.

No description available.

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.

Four experimentally naïve white Carneau pigeons learned to match three colors to each other in a variant of an Identity matching-to-sample procedure with an FR20 on samples and a response-initiated FI8-s on comparisons. In Experiment 1, the extent to which subjects were matching on the basis of identity was assessed by presenting, in extinction, test trials comprising novel stimuli serving as the sample (and matching comparison) or as the nonmatching comparison. The results from Experiment 1 suggested intermediate or little to no transfer on the basis of identity. Experiment 2 reassessed transfer on the basis of identity with differential reinforcement on the test trials. Under these conditions, two of the four birds demonstrated substantially better than chance levels of performance. These data imply that while the extended response requirements may be necessary, other procedural aspects may be responsible for generalized identity matching in the pigeon.