Marcus Bentes de Carvalho Neto

O jato de ar quente como estímulo punidor em rattus norvegicus

Na pesquisa experimental sobre controle aversivo, o choque eletrico tem sido predominantemente utilizado como estimulo punidor. O presente trabalho descreve o uso de um equipamento que emite um jato de ar quente o qual pode ser um estimulo alternativo a ser usado em estudos sobre contingencias aversivas. A funcao punidora do jato de ar quente foi avaliada tanto quando aplicado continuamente (CRF) quanto intermitentemente (FR3) e nos dois casos foi registrada supressao parcial (98,4% e 71,15%, respectivamente) da resposta de pressao a barra previamente fortalecida de forma continua. A supressao foi maior na punicao continua, corroborando os dados com choque eletrico descritos na literatura. O equipamento e o estimulo mostraram-se adequados do ponto de vista tecnico e cientifico e o aparato pode ser uma alternativa atraente do ponto de vista economico.

Punishment and the potential for negative reinforcement with histamine injection: Histamine Punishment and Negative Reinforcement

The present study examined punishment of responding with histamine injection, and its potential to generate avoidance of punishment. Sprague-Dawley rats were trained under concurrent schedules in which responses on one lever (the punishment lever) produced food under a variable-interval schedule, and under some conditions intermittent injections of histamine, which suppressed behavior. Responses on a second (avoidance) lever prevented histamine injections scheduled on the punishment lever. After stabilization of punished responding, a variable-interval 15-s schedule of cancellation of histamine (avoidance) was added for responding on the second/avoidance lever, without subsequent acquisition of responding on that lever. Progressive decreases in the length of the punishment variable-interval schedule increased suppression on the punishment lever without increases in response rates on the avoidance lever. Exchanging contingencies on the levers ensured that response rates on the avoidance lever were sufficiently high to decrease the histamine injection frequency; nonetheless response rates on the avoidance lever decreased over subsequent sessions. Under no condition was responding maintained on the avoidance lever despite continued punishing effectiveness of histamine throughout. The present results suggest that avoidance conditioning is not a necessary condition for effective punishment, and confirm the importance of empirical rather than presumed categorization of behavioral effects of stimulus events.

SUCCESSIVE APPROXIMATIONS TO SELECTIONISM: SKINNER’S FRAMEWORK FOR BEHAVIOR IN THE 1930S AND 1940S

Despite the centrality of selection by consequences in Skinnerian work, the adoption or not of a selectionist perspective in the first decades of Skinner’s career is a controversial theme. Inconsistencies with respect to his affiliation or not with a selectionist epistemology in this period seem to reflect a lack of consensual definition of that proposal. Therefore, from three previously defined aspects of Skinner’s selectionist explanatory principle, the aim of this review is to assess, through the texts produced in the 1930s and 1940s, whether selection by consequences was used as an explanatory mode for behavior or whether there were traces of an epistemology that would lead to selectionism. It has been noted that, although at this early stage the idea of a selective process is already implicit, there are still remnants of a traditional notion of causality that is incompatible with an explanatory principle based on a relation of probabilistic interdependence between events, which explains the origin and evolution of behavior as being the product of three histories of variation and selection.

Effects of different training histories upon manufacturing a tool to solve a problem: insight in capuchin monkeys (Sapajus spp.)

The emergence of novel behavior is a multilayered phenomenon that comprehends distinct processes. One such process is known as insightful problem solving. “Insight” can be explained as the spontaneous interconnection of previously acquired behavioral repertoires. The objective of this study was to investigate: (1) whether capuchin monkeys (Sapajus spp.) do show the interconnection of repertoires, and (2) whether different performances of problem solving could be produced by different training histories. Two repertoires were independently trained: (a) joining two pieces of a tool to manufacture a new tool and (b) raking food with one tool. In the test situation, food was out of reach, and two joinable pieces of a tool, different from the ones used in training, were presented. To solve the problem, the monkeys had to join the two pieces and rake the food with the new manufactured tool. In Experiment 1, one monkey received symmetric training (equal number of sessions) of both repertoires and solved the task, but not in an insightful manner. In Experiment 2, six monkeys were divided into two groups: one group received symmetric training, and the second group had asymmetrical training of the repertoires (unequal number of sessions). Subjects from the symmetric group performed as the monkey in Experiment 1; subjects from the other group showed a sudden insightful solution of the problem. The different performances in the same problem situation can be explained in terms of the behavioral history provided to each group of subjects.

Reflexões sobre a interinfluência entre ciência e política: o caso da homossexualidade

At the XXI Century it is a moment of intense ideological confl icts about civil rights for homosexuals, which have been usually grounded upon supposed scientifi c data or conceptions. This essay refl ects about the mutual infl uence between science and politic, through the case of the investigation of determinants of sexual orientation. To achieve that, it is presented a discussion regarding the infl uence of social and political issues involved in sexual orientation scientifi c research. Then the political use of scientifi c data is discussed, especially regarding the determinants of sexual orientation. Through the refl ections presented, this essay propose that the struggle to obtain civil rights should not be relayed upon the

Reflexiones sobre la interacción entre la ciencia y la política: el caso de la homosexualidad

At the XXI Century it is a moment of intense ideological confl icts about civil rights for homosexuals, which have been usually grounded upon supposed scientifi c data or conceptions. This essay refl ects about the mutual infl uence between science and politic, through the case of the investigation of determinants of sexual orientation. To achieve that, it is presented a discussion regarding the infl uence of social and political issues involved in sexual orientation scientifi c research. Then the political use of scientifi c data is discussed, especially regarding the determinants of sexual orientation. Through the refl ections presented, this essay propose that the struggle to obtain civil rights should not be relayed upon the

Reflections about the mutual influence between science and politics: the case of homosexuality

At the XXI Century it is a moment of intense ideological confl icts about civil rights for homosexuals, which have been usually grounded upon supposed scientifi c data or conceptions. This essay refl ects about the mutual infl uence between science and politic, through the case of the investigation of determinants of sexual orientation. To achieve that, it is presented a discussion regarding the infl uence of social and political issues involved in sexual orientation scientifi c research. Then the political use of scientifi c data is discussed, especially regarding the determinants of sexual orientation. Through the refl ections presented, this essay propose that the struggle to obtain civil rights should not be relayed upon the

Um Modo Alternativo de Construir um Operante: A Aprendizagem Recombinativa

Analistas do comportamento consideram a modelagem o procedimento de construcao de repertorios comportamentais por excelencia. Contudo, existem outras formas de se instalar uma nova resposta complexa sem a necessidade da construcao gradual e direta do repertorio final. O presente trabalho apresenta um modelo de recombinacao espontânea (aprendizagem recombinativa ou generativa) de repertorios previamente estabelecidos de modo independente (nao diretamente treinados). Tal modelo foi aqui utilizado para tentar instalar a cadeia de respostas: (a) subir em uma caixa e (b) puxar uma corrente, executada por um rato albino (Rattus norvegicus). Discutem-se as caracteristicas de cada tipo de aprendizagem (modelagem e recombinativa), bem como as implicacoes do modelo ora apresentado para a compreensao ontogenetica de padroes com- portamentais chamados de criativos ou originais. Palavras-chave: Aprendizagem recombinativa; aprendizagem generativa; modelagem; insight; rattus norvegicus.