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Nitrous oxide (N2O) is a widely used anesthetic adjunct in dentistry and medicine that is also commonly abused. N2O alters the function of several receptors in vitro and ex vivo, however, the receptors systems underlying its abuse-related intoxicating effects are poorly understood. The goals of this dissertation were to (1) establish N2O as a discriminative stimulus, (2) characterize the temporal properties of the discriminative stimulus, (3) determine the degree of similarity between N2O and other inhalants and (4) explore the neurochemical effects responsible for the stimulus properties of N2O. Twenty-four mice were trained to discriminate 10 minutes exposure to 60% N2O+40% O2 from 100% O2 in daily 5 minute food-reinforced operant sessions. Mice acquired the discrimination in a mean of 38 sessions. N2O produced concentration-dependent full substitution for itself. Full substitution required 7 minutes of N2O exposure but the offset of stimulus effects following cessation of N2O exposure were more rapid. Varying degrees of partial substitution for N2O were engendered by abused vapors and vapor anesthetics. The aromatic hydrocarbon toluene produced the most robust substitution for N2O. One or more toluene concentrations produced full substitution for N2O in 7 of 8 subjects, suggesting that these two abused inhalants share common neurochemical mechanisms. The NMDA receptor open channel blockers (+)-MK-801, ketamine and memantine produced dose-dependent partial substitution for N2O. A competitive NMDA antagonist and NMDA glycine site antagonist did not substitute for N2O. Pretreatment with (+)-MK-801 as well as ethanol produced dose-dependent leftward shifts in the N2O concentration effect curve further suggesting some overlap in their mechanisms of action. GABAA agonists and positive allosteric modulators, opioid agonists, serotonergic agonists, nicotine, a nNOS inhibitor and the psychomotor stimulant amphetamine all failed to appreciably substitute for N2O and/or failed to alter the N2O concentration effect curve when administered prior to N2O exposure. No drug tested produced greater than 80% mean N2O-lever selection leaving open the possibility of other neurochemical contributors to the stimulus effects of N2O.

The purpose of this study was to assess if Behavioral Skills Training (BST) can be used to train a sticker to function as a discriminative stimulus (Sᴰ) for engaging in household poison safety skills and assess whether this skill generalized to untrained household chemicals that bear the Sᴰ in the form of a sticker. Three typically developing children ages 3 and 5 and their parents participated in this study which took place in their homes. BST effectively taught children to engage in household poison safety skills when they come into contact with the trained household poison(s) labeled with the sticker Sᴰ and this skill generalized to novel household poisons that were also labeled with the sticker Sᴰ; however, some additional BST was required in two cases.

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.

L’addiction aux drogues peut être considérée comme une maladie neurologique chronique avec des rechutes récurrentes en période d’abstinence qui constituent le problème majeur dans le traitement de l’addiction aux drogues. Grâce à un modèle animal de rechute, il a été montré qu’un rongeur pouvait réinstaller un comportement de recherche de drogue lorsqu’il était réexposé à la drogue elle-même, à des indices associés à la drogue, ou encore à un stress. Dans notre équipe, nous avons évalué la contribution relative des différentes propriétés de la cocaïne, de l’héroïne et de la nicotine (incitative, discriminative et renforçante) dans la réinstallation d’un comportement de recherche de nourriture. Afin de dissocier les propriétés discriminatives et renforçantes, les rats ont été entraînés à s’auto-administrer une récompense alimentaire. Nous avons alors trouvé que : 1) La cocaïne et la nicotine agissent comme des stimuli internes qui acquièrent un contrôle discriminatif sur le comportement, étant donné que la cocaïne et la nicotine, contrairement à l’héroïne, peuvent réinstaller un comportement éteint de recherche de nourriture lorsque ce comportement a été préalablement acquis sous les effets de la cocaïne et de la nicotine, respectivement. 2) La réinstallation induite par la cocaïne et la nicotine est indépendante de la valeur actuelle de la récompense, ce qui indique que la cocaïne et la nicotine contrôlent l’activation de comportements automatiques, habituels, liés à la drogue. Puis, afin d’identifier la façon dont les drogues d’abus entraînent la formation d’habitudes, nous avons également étudié les effets d’une sensibilisation à la cocaïne à différents moments d’un apprentissage instrumental pour une récompense alimentaire, après une dévaluation de la récompense. Nous avons alors trouvé que la sensibilisation à la cocaïne ne favorisait pas le développement de comportements de type habituel. Cette série d’expériences constitue une première étape dans la comparaison des processus automatiques produits par la cocaïne et la nicotine. Si l’activation de comportements de type habituel, automatique, peut être généralisée à d’autres drogues d’abus, nous pourrons considérer que la rechute vers la recherche et la prise de drogue est en partie sous le contrôle de processus automatiques, ce qui pourrait expliquer la forte probabilité de rechute, même après de longues périodes d’abstinence et malgré la connaissance des conséquences néfastes qui en découlent. / Drug addiction can be considered as a chronic brain disease with recurrent relapse during abstinence periods which remains the major problem for the treatment of drug addiction. Using an animal model of drug relapse, it has been shown that a rodent can reinstate a drug-seeking behavior when re-exposed to the drug itself, drug associated cues or stress. In our research group, we assessed the relative contribution of the different properties of cocaine, heroin and nicotine (incentive, discriminative and reinforcing) in food-seeking reinstatement, and in order to dissociate the discriminative from the reinforcing properties, rats were trained to self-administer a non-drug reward (food). We found that: 1) Cocaine and nicotine act as internal stimuli that acquires discriminative control over behavior, since cocaine and nicotine, but not heroin, can reinstate an extinguished food-seeking behavior when this behavior has been previously performed under the effects of cocaine and nicotine respectively. 2) Cocaine- and nicotine-induced reinstatement is independent of the current value of the outcome, which indicates that cocaine and nicotine control the activation of automatic, drug-related habitual behaviors. Then, in order to identify the way drugs of abuse lead to the formation of habits, we also examined the effects of cocaine sensitization at different stages of instrumental training for a food reward after outcome devaluation. We found that, globally, cocaine sensitization does not promote the development of habit-based behaviors. This series of experiments represent a first step in the comparison of automatic processes produced by cocaine and nicotine. If the activation of automatic, habit-based behaviors can be generalized to other drugs of abuse, we could consider that relapse to drug-seeking and drug-taking is partly under the control of automatic processes, which could explain the high probability of relapse, even after extended periods of abstinence and despite the knowledge of the adverse consequences.

Made available in DSpace on 2016-04-29T13:18:18Z (GMT). No. of bitstreams: 1 Mariana Cavalcante Vieira.pdf: 1576858 bytes, checksum: a83e1d1db29f1a44bbcb3e8d8910ab78 (MD5) Previous issue date: 2010-04-19 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Metacontingency is the unit of analysis at the cultural level proposed in analogy to the three-term contingency to explain social phenomena that involves the functional relation between interlocking behavioral contingencies (IBC) and its aggregate outcome and the cultural consequence. So far, experimental research has investigated the relation equivalent to the response-reinforcer in the operant contingency. In this study, the following questions were made: (1) An antecedent stimulus similar to the DS assume evocative function to IBC and their aggregate outcome in a metacontingency? (2) What are the effects of alternating two antecedent stimuli, each one correlated to a specific metacontingency? (3) Will the establishment of an analogous to discriminative stimuli control produce an analog of generalization process? Fifteen college students participated in this study, in a total of 12 generations (3 participants in each). This study had seven experimental conditions in an trial procedure. One to three participants worked simultaneously, each one in a computer: the participant of the left (PL), center (PC) and right (PR). In each trial, the computer screen of each participant, presented four numbers, independently, in each column. The participant had to enter another four in matching columns. If the sums of the numbers presented by the computers and the numbers in each column selected by the participant resulted in odd numbers, the participant earned points. This contingency was called individual contingency. Two other contingencies focused on relations between the products of the behavior of the participants, called metacontingencies. In metacontingency 1, the background color of the screen was blue (SM1) and the sum of 4 numbers entered by the participant PL was smaller than the sum of 4 numbers entered by the participant PC and this sum was smaller than the sum of 4 numbers entered by PR (ΣPL <ΣPC <ΣPR), a cultural consequence was produced: the participants received additional credits called bonus. In metacontingency 2, the screens had a red background (SM2) and the participants produced bonus if "ΣPL> ΣPC> ΣPR . These metacontingencies were presented in random order between trials. When stability criteria was reached, older participants were replaced by newer participants. Tests of stimulus control and generalization were presented at established moments. The results showed the selection of operant behavior and metacontingencies 1 and 2 and indicated that SM1 and SM2 acquired evocative function of the corresponding metacontingencies. The tests suggested that the background colors of the screen became the stimulus dimension that exerted control over the behavior of the participants and their interactions. The data are discussed in terms of an analogy between operant contingency and metacontingency / A metacontingência é a unidade de análise no nível cultural proposta em analogia à tríplice contingência para explicar fenômenos sociais que envolvem a relação funcional entre contingências comportamentais entrelaçadas (CCE) e seu produto agregado e uma conseqüência cultural. Até o momento, as pesquisas experimentais investigaram o equivalente à relação resposta-reforçador da contingência operante. No presente estudo, as seguintes perguntas foram feitas: (1) Uma condição de estímulo antecedente análoga ao SD assumiria função evocativa sobre CCEs e seu produto agregado em uma metacontingência? (2) Quais seriam os efeitos de alternar duas condições de estímulo antecedentes, sendo cada uma delas correlacionada a uma metacontingência específica? (3) O estabelecimento do controle de estímulos análogo ao discriminativo produziria processos análogos ao de generalização? Participaram do estudo 15 estudantes universitários, totalizando 12 gerações (3 participantes em cada). O estudo teve sete condições experimentais em procedimento de tentativas. Um a três participantes trabalhavam simultaneamente, cada um em um computador: o participante da esquerda (PE) do centro (PC) e da direita (PD). Em cada tentativa, nas telas dos computadores de cada participante, eram apresentados, independentemente, quatro números um em cada coluna e cabia ao participante inserir outros quatro também em quatro colunas. Se as somas dos números apresentados pelos computadores e dos números selecionados em cada coluna pelo participante resultassem em números ímpares, o participante ganhava pontos. Esta contingência foi chamada de contingência individual. Outras duas contingências incidiam sobre relações entre os produtos dos comportamentos dos participantes, chamadas de metacontingências. Na metacontingência 1, a cor de fundo da tela era azul (SM1) e se a soma dos 4 números inseridos pelo participante PE fosse menor que a soma dos 4 números inseridos pelo participante PC e esta soma fosse menor que a soma dos 4 números inseridos por PD ( ∑PE ∑PC ∑PD ), uma conseqüência cultural era produzida: os participantes recebiam créditos adicionais chamado bônus. Na metacontingência 2, as telas tinham fundo vermelho (SM2) e os participantes produziam bônus se ∑PE ∑PC ∑PD . Estas metacontingências eram apresentadas em ordem aleatória entre tentativas. Atingidos critérios de estabilidade, os participantes antigos eram substituídos por participantes novatos. Em momentos pré-estabelecidos foram conduzidos testes de controle de estímulos e de generalização. Os resultados mostraram a seleção do comportamento operante e das/ pelas metacontingências 1 e 2 e indicaram que SM1 e SM2 adquiriram função evocativa sobre as metacontingências correspondentes. Os testes sugeriram que as cores de fundo da tela tornaram-se a dimensão do estímulo que exerceu controle sobre os comportamentos dos participantes e suas interações. Os dados são discutidos em termos de uma analogia entre contingência operante e metacontingência

Relational Frame Theory research involves either of two protocols utilized to establish relational networks and functions for stimuli in those relational networks. Years of research indicate the most prevalent method involves first establishing a relational frame, conditioning one of the stimuli to acquire a particular function, and then providing a test to see if the function trained to one of the stimuli in the network transferred through the relational network to other stimuli. The less common method involves first training a particular function for a stimulus, entering that stimulus in a relational network with at least two other stimuli, and then subsequently providing a test to see if the function transferred. Hayes, Kohlenberg, and Hayes (1991) hypothesized that not only do both procedures work, but there is also no differentiation between the two with regards to transformation of stimulus function. Although both protocols have been used in the RFT literature, a direct comparison has never been made. The current study directly examines that comparison in a within-subject analysis to determine if there may be differentiated results in transformation of stimulus function based on the protocol used. A within-subjects analysis indicates that subsequent probes of transformation of stimulus function probes yielded similar levels of correct responding in both training protocols, and thus supporting the hypothesis put forth by Hayes and colleagues (1991).

Social stimuli that function as reinforcers for most children generally do not function as reinforcers for children diagnosed with autism. These important social stimuli include smiles, head nods, thumb-ups, and okay signs. It should be an important goal of therapy for children with autism to condition these neutral social stimuli to function as reinforcers for children diagnosed with autism. There is empirical evidence to support both a pairing procedure (classical conditioning) and a discriminative stimulus procedure to condition neutral stimuli to function as reinforcers. However, there is no clear evidence as to the superiority of effectiveness for either procedure. Despite this most textbooks and curriculum guides for children with autism state only the pairing procedure to condition neutral stimuli to function as reinforcers. Recent studies suggest that the discriminative stimulus procedure may in fact be more effective in conditioning neutral stimuli to function as reinforcers for children diagnosed with autism. The present research is a further comparison of these two procedures. Results from one participant support recent findings that suggest the discriminative stimulus procedure is more effective in conditioning neutral stimuli to function as reinforcers. But the results from the other participant show no effects from either procedure, suggesting future research into conditions necessary to condition neutral social stimuli to function as reinforcers for children with autism.

Made available in DSpace on 2016-04-29T13:18:02Z (GMT). No. of bitstreams: 1 Lilian Evelin dos Santos.pdf: 696473 bytes, checksum: 4b3297aade76d4ea7d8436d44b6b10d8 (MD5) Previous issue date: 2005-04-19 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The present study was a replication of Dymond & Barnes (1994). The study aimed: (a) to verify if the establishment of a pattern of responding as a discriminative stimulus, consistently paired with a stimulus that belonged to a class of equivalent stimuli, would establish the pattern of responding as a member of the same equivalence class, and (b) to verify if the other stimuli of the stimulus class would control responding as a discriminative stimulus, through the insertion of the response pattern in the class. The experimental procedure had 4 phases: (1) a conditional discrimination training and tests for the emergence of two equivalence classes of 3 stimuli (A1, B1, C1 and A2, B2, C2); (2) a self-discrimination training where two distinct response patterns (clicking or not clicking a mouse, in a 5s period) each one systematically paired with one stimulus of each of the equivalence classes (B1 or B2) were established as conditional stimuli controlling the discriminative function of two stimuli (B1 and B2); (3) Test 1: of the possible control of the self-discrimination response over new stimuli, where it was tested if the response patterns with the mouse also controlled the choice between two other stimuli of the equivalence class (C1 and C2), which were never before paired with responding with the mouse; and (4) Test 2: of the possible control, by the stimuli of the equivalence class, over the pattern of responding with the mouse, where it was tested if a choice of either C1 or C2 was followed by responding / not responding with the mouse. Of the 11 adults who started the experiment, 6 completed the study: the performance of 4 of these 6 participants on Test 1 and of 3 of them on Test 2 were successful. Results were similar to the ones found by Dymond & Barnes (1994), suggesting that: (a) response patterns may acquire behavioral functions as stimuli and may become part of equivalence stimulus classes, and (b) stimuli that are part of a equivalent stimulus class may share behavioral functions, because of a history of differential reinforcement related to only one member of the stimulus class / O presente estudo foi uma replicação de Dymond e Barnes (1994). Seu objetivo foi verificar se (1) o estabelecimento de um padrão de respostas como estímulo discriminativo para outras respostas de um individuo tornaria a resposta (como SD)_membro de uma classe de estímulos equivalentes da qual faz parte um estímulo sistematicamente pareado com a resposta discriminada (e discriminativa), sem qualquer treino direto e se, por outro lado, (2) a participação dessa resposta como membro da classe de estímulos equivalentes tornaria os outros estímulos membros da classe estímulos discriminativos para as mesmas respostas controladas dicriminativamente pela resposta. O procedimento consistiu em quatro fases: 1) treino de discriminação condicional e teste de formação de estímulos equivalentes para a formação de duas classes de três estímulos (A1, B1, C1 e A2, B2 e C2); 2) treino de autodiscriminação, no qual dois diferentes padrões de responder (clicar ou não clicar o mouse num período de 5s) pareados, cada um deles com um estímulo de cada classe de estímulos equivalentes (B1 e B2) - foram estabelecidos como estímulos condicionais numa segunda tarefa - de escolha entre dois estímulos (B1 e B2), cada um deles membro de uma das classes de estímulo equivalente estabelecidas anteriormente; 3) Teste 1: do controle da resposta de autodiscriminação sobre novos estímulos, no qual se testou se os padrões de responder (clicar / não clicar o mouse) controlariam a resposta de escolha entre dois estímulos das classes de equivalência (C1 ou C2), jamais pareados com esses desempenhos e; 4) Teste 2: do controle dos estímulos da classe de estímulos equivalentes sobre o responder , no qual se testou se a escolha entre os estímulos C1 e C2 (que seria controlada pelo desempenho no mouse) passaria a controlar o desempenho posterior no mouse. Participaram deste estudo 11 adultos, dos quais 6 concluíram o experimento. Dos participantes que concluíram, 4 tiveram um desempenho positivo no Teste 1, e destes, 3 tiveram também um desempenho positivo no Teste 2. Os resultados sugeriram que: a) padrões de respostas podem adquirir funções comportamentais de estímulos e podem fazer parte de classes de estímulos equivalentes e b) estímulos que participam de uma classe de estímulos equivalentes podem compartilhar as mesmas funções comportamentais, a partir de uma história de reforçamento diferencial em relação a apenas um estímulo pertencente à classe

Feedback is discussed in many disciplines. In behavior analysis, it has been discussed in terms of its functions, many coming to different conclusions. The present study evaluated whether therapists' preferred temporal and format of feedback shifted or changed during acquisition or maintenance of skills implementing a tact program using a token economy system after a brief exposure to all possible feedback combinations. Three participants completed a questionnaire before they were exposed to a feedback sampling phase and preferred feedback phase. Preferred way of recieving feedback was asked at the beginning of each session. Two out of three participants switched preferences after achieving mastery of task. Task mastery may make feedback delivered at the end of a session more desirable while task acquisition may make feedback delivered at the end of a trial more valuable. Limitations and future research were discussed.