RESUMO

The addition of nanostructures to polymeric materials allows for a direct interaction between polymeric chains and nanometric structures, resulting in a synergistic process through the physical (electrostatic forces) and chemical properties (bond formation) of constituents for the modification of their properties and potential cutting-edge materials. This study explores a novel in situ synthesis method for PDMS-%SiO2 nanoparticle composites with varying crosslinking degrees (PDMS:TEOS of 15:1, 10:1, and 5:1); particle concentrations (5%, 10%, and 15%); and sol-gel catalysts (acidic and alkaline). This investigation delves into the distinct physical and chemical properties of silicon nanoparticles synthesized under acidic (SiO2-a) and alkaline (SiO2-b) conditions. A characterization through Raman, FT-IR, and XPS analyses confirms particle size and agglomeration differences between both the SiO2-a and SiO2-b particles. Similar chemical environments, with TEOS and ethanol by-products, were detected for both systems. The results on polymer composites elucidate the successful incorporation of SiO2 nanoparticles into the PDMS matrix without altering the PDMS's chemical structure. However, the presence of nanoparticles did affect the relative intensities of specific vibrational modes over composites from -35% to 24% (Raman) and from -14% to 59% (FT-IR). The XPS results validate the presence of Si, O, and C in all composites, with significant variations in atomic proportions (C/Si and O/Si) and Si and C component analyses through deconvolution techniques. This study demonstrates the successful in situ synthesis of PDMS-SiO2 composites with tunable properties by controlling the sol-gel and crosslinking synthesis parameters. The findings provide valuable insights into the in situ synthesis methods of polymeric composite materials and their potential integration with polymer nanocomposite processing techniques.

RESUMO

The use of nanoparticles (NPs) as reinforcements in polymeric coatings allows for direct interaction with the polymeric chains of the matrix, resulting in a synergistic process through physical (electrostatic forces) and chemical interactions (bond formation) for the improvement of the mechanical properties with relatively low weight concentrations of the NPs. In this investigation, different nanocomposite polymers were synthesized from the crosslinking reaction of the hydroxy-terminated polydimethylsiloxane elastomer. Different concentrations (0, 2, 4, 8, and 10 wt%) of TiO2 and SiO2 nanoparticles synthesized by the sol-gel method were added as reinforcing structures. The crystalline and morphological properties of the nanoparticles were determined through X-ray diffraction (XRD), Raman spectroscopy, and transmission electron microscopy (TEM). The molecular structure of coatings was through infrared spectroscopy (IR). The crosslinking, efficiency, hydrophobicity, and adhesion degree of the study groups were evaluated with gravimetric crosslinking tests, contact angle, and adhesion tests. It was observed that the crosslinking efficiency and surface adhesion properties of the different nanocomposites obtained were maintained. A slight increase in the contact angle was observed for the nanocomposites with 8 wt% compared to the polymer without reinforcements. The mechanical tests of indentation hardness and tensile strength following the ASTM E-384 and ISO 527 standards, respectively, were performed. As the nanoparticle concentration increased, a maximum increase of 157% in Vickers hardness, 71.4% in elastic modulus, and 80% in tensile strength was observed. However, the maximum elongation remained between 60 and 75%, ensuring that the composites did not become brittle.

RESUMO

Resumen En el presente estudio se investigó si la frecuencia de las actividades hechas por la pareja tiende a igualar la frecuencia de las actividades recibidas del cónyuge; conforme a la ley de igualación. Participaron 120 hombres y 120 mujeres divididos en seis bloques de cinco años de matrimonio cada uno. Se pidió a los participantes que, de una lista de 63 actividades divididas en 9 áreas de interacción marital, indicaran cuáles realizaban por y cuáles recibían de su pareja. Posteriormente, se estimó si la proporción de actividades que los miembros de la pareja reportaron que hacían por su pareja tendía a igualar la proporción de actividades que decían recibir de ella. Los participantes reportaron que la proporción de actividades que hacen por su pareja es similar a la proporción de actividades que reciben de ella. Estos hallazgos sugieren que la relación entre las actividades del matrimonio y los reforzadores que mantienen unida a una pareja puede explicarse cuantitativamente con la ley de igualación; esto es, en términos de la relación entre los patrones de conducta que los miembros de la pareja hacen por y reciben de su pareja.

Abstract In the present study, it was explored if the frequency of the activities done for the spouse tends to match the frequency of the activities received from the partner, according to the matching law. Participants were 120 men and 120 women divided into six blocks of five years of marriage each one; that is, from 1 to 5, 6 to 10, 11 to 15, 16 to 20, 21 to 25, and more than 26 years of marriage. They were asked to choose, from a list of 63 activities divided into 9 areas of marital interaction (household responsibilities, raising children, social activities, finance, communication, sexual interaction, occupational or academic progress, personal independence, and spouse independence), which activities they performed for their partner and which ones they received from them. Based on the importance scores reported in a previous study, the proportion of the reinforcing value of the 63 marital activities was calculated. Subsequently, it was estimated whether the proportion of activities done for the spouse tends to equate the proportion of activities received from the partner. It was found that the proportion of activities the participants do for their partners is similar to the proportion of activities they received from them. Linear regressions were calculated for each block of years of marriage with the proportion of activities done predicted by the proportion of activities received. With these regressions, the deviation of the matching between the proportions was estimated. Slopes greater than 1.0 would show that participants reported to do more activities than they reported to receive; slopes lower than 1.0 would show that participants did fewer activities than those received; and if the value is close to 0.5 it would indicate indifference; that is, participants would do the same number of activities, regardless of those received from their partner. It was found that for men the slope varied between 0.71 and 1.02, and for women the slope varied between 0.908 and 1.035. These findings suggest that the relationship between marital activities and the reinforcers that hold a couple together can be explained quantitatively by the matching law; this is, by the correlation between the activities done for and receive from the spouse.

RESUMO

Resumo Neste estudo investigou-se a emergência de classes de equivalência generalizada, com inclusão de reforçadores específicos em bebês de 24 meses. Relações auditivo-visuais (AB e AC) foram ensinadas, com consequências específicas (D), para 5 bebês entre 18 e 20 meses de idade. Testes de nomeação e de relações emergentes foram realizados (BC, CB, AD, DE e EB, com semelhança física dos estímulos E e B). Três participantes formaram de classes de equivalência, incluindo os reforçadores específicos (ABCD), e dois deles apresentaram nomeação consistente. Dois participantes apresentaram desempenho correspondente à equivalência generalizada. Os resultados indicaram (a) a inédita formação de classes de equivalência generalizada com inclusão de reforçadores específicos em bebês, e (b) que a nomeação pode não ser condição necessária para a formação de classes.

Abstract This study assessed the emergence of generalized equivalence classes, with the inclusion of specific reinforcers, by infants up to 24 months old. Auditory-visual relations (AB and AC) were taught, with specific consequences (D), for five infants aged between 18 and 20 months. Naming and emergent relations tests (BC, CB, AD, DE and EB, with B and E stimuli physically similar). Three participants demonstrated equivalence classes formation, including specific reinforcers (ABCD), and two of them presented consistent naming. Two participants demonstrated generalized equivalence classes. The results indicated the unprecedented formation of generalized equivalence classes with the inclusion of specific reinforcers in babies, and that naming may not be a necessary condition for the formation of classes.

RESUMO

In the context of applying behavior-analytic principles to the study of the evolution of human societies, we propose that rules constitute the basic units of sociocultural selection. Such thesis is based on a critical analysis of the ideas concerning sociocultural selection proposed by Skinner and Baum. Its point of departure is a new functional concept of rule uttering, defined as a special type of verbal behavioral pattern, whose probability of occurrence depends upon their probability of altering the frequency of certain kind of behavior in the repertoire of a given individual or group of individuals. These relatively lasting changes in the behavior of recipients include the uttering of rules appropriate to specific types of problem situations, which increase the likelihood of responses that solve the problems faced by the social group. According to the proposed model, rule-uttering behavioral patterns include rule application, rule transmission and rule creation, which are functionally distinguished by the social consequences they produce. Patterns of rule uttering are selected by operant mechanisms, in the sense that those that do not increase the probability of solving problems tend to stop occurring. It is proposed that the occurrence probability of generalized social reinforcers, associated to different functionally specialized social systems (e.g., money in the economy, sanctions in the legal system), constitutes the main consequence responsible for rule-uttering selection.

RESUMO

Seven participants received conditional discrimination training that established the 12 conditional relations A1B1, A2B2, A3B3, A1C1, A2C2, A3C3, D1E1, D2E2, D3E3, D1F1, D2F2, and D3F3. The A stimuli were pictures of faces portraying emotional expressions; the others were arbitrary forms. Correct responses resulted in presentations of class-specific reinforcers, Sr1, Sr2, and Sr3. After training, tests confirmed the formation of ABC and DEF equivalence classes. Further tests then documented the merger of the classes and the emergence of SrB, SrC, SrE, and SrF relations, showing that the class-specific reinforcers were equivalence class members. Finally, participants did Semantic Differential ratings that tested whether the emotional valence of the A stimuli transferred to the arbitrary forms, B and E. The results show that participants' evaluations of the B and E stimuli were similar to evaluations of the A stimuli made by participants of a control group. This finding is considered as a demonstration that class-specific outcomes can mediate class merger phenomena and the transfer of functions through members of merged classes.

Assuntos

RESUMO

Resumo A presente pesquisa teve por objetivo investigar o efeito da apresentação e da retirada de reforçadores sobre a correspondência verbal. Oito crianças brincaram individualmente e, em seguida, relataram com quais brinquedos haviam brincado. Após linha de base, os relatos de "não brincar", feitos ora individualmente, ora em grupo, foram punidos (perda de fichas permutáveis por brinquedos). Em seguida, os participantes foram divididos em dois grupos, que passaram por um de dois procedimentos: (1) punição negativa de relatos não correspondentes; ou (2) reforçamento positivo de relatos correspondentes. A punição negativa somente de relatos de "não brincar" produziu um aumento no número de relatos não correspondentes de brincar para quatro crianças e, posteriormente, dificultou o restabelecimento da correspondência, seja sob uma punição negativa, seja sob reforçamento positivo.

Abstract The present study aimed to investigate the effect of presentation and withdrawal of reinforcers on verbal correspondence. Eight children individually played with toys, and then reported with what toys they had played. After baseline, reports of "no play", sometimes made individually, sometimes in groups, were punished (loss of tokens exchangeable for toys). Next, the participants were divided into two groups, whose participants underwent one of two procedures: (1) negative punishment of not corresponding reports; or (2) positive reinforcement of corresponding reports. The negative punishment of reports of "no play" produced an increase in the number of non-correspondent "play" reports for four children, and subsequently hindered the recovery of correspondence, either by negative punishment or by positive reinforcement.

RESUMO

A explicação segundo a qual classes de equivalência são formadas por contingências de reforço, tem como implicação que respostas e estímulos reforçadores também seriam incluídos entre seus membros. Suporte empírico a essa tese vem de experimentos utilizando reforçadores específicos para cada classe potencial, tanto em contexto de discriminação condicional, quanto de discriminação simples, neste último caso em combinação com reversões sistemáticas, em que as funções S+ e S- dos estímulos discriminativos são constantemente invertidas. Em ambos os casos, testes apropriados evidenciaram a inclusão dos estímulos reforçadores como membros das classes de equivalência. Esses resultados permitem supor que estímulos reforçadores também participariam de classes ordinais. Estas são definidas pelas propriedades: assimetria, irreflexividade, transitividade, substituibilidade e conectividade. De caráter preliminar, o presente estudo testou uma estratégia experimental como um primeiro passo para uma investigação sobre a inclusão de estímulos reforçadores como membros de classes ordinais. Seu objetivo foi investigar o efeito de reforçadores condicionados específicos na formação de classes ordinais. Na presença de um estímulo condicional, seis universitários deviam sequenciar formas não representacionais numa determinada ordem, ao que seguia-se a apresentação de um trecho musical. Na presença de outro estímulo condicional, os mesmos estímulos deviam ser sequenciados na ordem inversa, produzindo outro trecho musical. Testes evidenciaram que além da emergência das propriedades definidoras de classes ordinais, os trechos musicais intercambiaram sua função reforçadora aos estímulos condicionais. Sendo a estratégia experimental eficaz nesse sentido, o próximo passo será verificar sua eficácia para promover a inclusão de reforçadores como membros de classes sequenciais.(AU).

The explanation according to which equivalence classes are formed by contingencies of reinforcement, has the implication that responses and reinforcer stimuli would also be included among its members. Empirical support for this theory comes from experiments using specific reinforcers to each potential class, both in the context of conditional discrimination as in the simple discrimination context, in the latter case in combination with systematic reversals, in which S+ and S- functions of the discriminative stimuli are constantly reversed. In the two cases, appropriated tests showed the inclusion of reinforcer stimuli as members of the equivalence classes. These results encourage hypothesize that reinforcer stimuli also participate in ordinal classes, which are defined by the properties: asymmetry, inflexibility, transitivity, substitutability and connectedness. Preliminary, this study tested an experimental strategy as a first step toward an investigation on the inclusion of reinforcing stimuli as members of sequential classes. Its aim was to investigate the effect of specific conditioned reinforcers in the formation of ordinal classes. In the presence of one conditional stimulus, six university students had to make sequences of abstract pictures in a determined order that were followed by the presentation of one musical passage. In the presence of another conditional stimulus, the same stimuli had to be sequenced in the reverse order, producing another musical excerpt. Tests showed that in addition to the emergence of defining properties of ordinal classes, the musical excerpts exchanged their reinforcing function for the conditional stimulus function.(AU).

La explicación según la cual clases de equivalencia son formadas por las contingencias de refuerzo, tiene como implicación que respuestas y estímulos reforzadores también serían incluídos entre sus membros. Soporte empírico para esa tesis viene de experimentos utilizando reforzadores específicos para cada clase potencial, tanto en contexto de discriminación condicional, cuánto de discriminación simple, en este último caso en combinación con reversones sistemáticas, en que las funciones S+ e S- de los estímulos discriminativos son constantemente invertidas. En ambos los casos, testes apropiados evidenciaron la inclusión de los estímulos reforzadores como miembros de las clases de equivalencia. Éses resultados permiten suponer que estímulos reforzadores también participarían de clases secuenciales. Éstas son definidas por las propiedades: irreflexividad, asimetría, transitividad, conectividad y substitubilidad. De carácter preliminar, el presente estudio, examinó una estrategia experimental como uno primero paso para una investigación sobre la inclusión de estímulos reforzadores como miembros de clases secuenciales. Su objetivo fue investigar el efecto de reforzadores condicionados específicos en la formación de clases ordinales. En la presencia de uno estímulo condicional, seis universitarios debían secuenciar figuras abstractas en una determinada orden, lo que seguia-se la apresentación de una pasaje musical. En la presencia de otro estímulo condicional, los mismos estímulos debían ser secuenciados, en la orden inversa, producindo otra pasaje musical. Testes evidenciaron que más adelante da emergencia de las propiedades definidoras de clases secuenciales, los pasajes musicales intercambiaron su función reforzadora para la de estímulos condicionales.(AU).

Assuntos

RESUMO

A explicação segundo a qual classes de equivalência são formadas por contingências de reforço, tem como implicação que respostas e estímulos reforçadores também seriam incluídos entre seus membros. Suporte empírico a essa tese vem de experimentos utilizando reforçadores específicos para cada classe potencial, tanto em contexto de discriminação condicional, quanto de discriminação simples, neste último caso em combinação com reversões sistemáticas, em que as funções S+ e S- dos estímulos discriminativos são constantemente invertidas. Em ambos os casos, testes apropriados evidenciaram a inclusão dos estímulos reforçadores como membros das classes de equivalência. Esses resultados permitem supor que estímulos reforçadores também participariam de classes ordinais. Estas são definidas pelas propriedades: assimetria, irreflexividade, transitividade, substituibilidade e conectividade. De caráter preliminar, o presente estudo testou uma estratégia experimental como um primeiro passo para uma investigação sobre a inclusão de estímulos reforçadores como membros de classes ordinais. Seu objetivo foi investigar o efeito de reforçadores condicionados específicos na formação de classes ordinais. Na presença de um estímulo condicional, seis universitários deviam sequenciar formas não representacionais numa determinada ordem, ao que seguia-se a apresentação de um trecho musical. Na presença de outro estímulo condicional, os mesmos estímulos deviam ser sequenciados na ordem inversa, produzindo outro trecho musical. Testes evidenciaram que além da emergência das propriedades definidoras de classes ordinais, os trechos musicais intercambiaram sua função reforçadora aos estímulos condicionais. Sendo a estratégia experimental eficaz nesse sentido, o próximo passo será verificar sua eficácia para promover a inclusão de reforçadores como membros de classes sequenciais.

The explanation according to which equivalence classes are formed by contingencies of reinforcement, has the implication that responses and reinforcer stimuli would also be included among its members. Empirical support for this theory comes from experiments using specific reinforcers to each potential class, both in the context of conditional discrimination as in the simple discrimination context, in the latter case in combination with systematic reversals, in which S+ and S- functions of the discriminative stimuli are constantly reversed. In the two cases, appropriated tests showed the inclusion of reinforcer stimuli as members of the equivalence classes. These results encourage hypothesize that reinforcer stimuli also participate in ordinal classes, which are defined by the properties: asymmetry, inflexibility, transitivity, substitutability and connectedness. Preliminary, this study tested an experimental strategy as a first step toward an investigation on the inclusion of reinforcing stimuli as members of sequential classes. Its aim was to investigate the effect of specific conditioned reinforcers in the formation of ordinal classes. In the presence of one conditional stimulus, six university students had to make sequences of abstract pictures in a determined order that were followed by the presentation of one musical passage. In the presence of another conditional stimulus, the same stimuli had to be sequenced in the reverse order, producing another musical excerpt. Tests showed that in addition to the emergence of defining properties of ordinal classes, the musical excerpts exchanged their reinforcing function for the conditional stimulus function.

La explicación según la cual clases de equivalencia son formadas por las contingencias de refuerzo, tiene como implicación que respuestas y estímulos reforzadores también serían incluídos entre sus membros. Soporte empírico para esa tesis viene de experimentos utilizando reforzadores específicos para cada clase potencial, tanto en contexto de discriminación condicional, cuánto de discriminación simple, en este último caso en combinación con reversones sistemáticas, en que las funciones S+ e S- de los estímulos discriminativos son constantemente invertidas. En ambos los casos, testes apropiados evidenciaron la inclusión de los estímulos reforzadores como miembros de las clases de equivalencia. Éses resultados permiten suponer que estímulos reforzadores también participarían de clases secuenciales. Éstas son definidas por las propiedades: irreflexividad, asimetría, transitividad, conectividad y substitubilidad. De carácter preliminar, el presente estudio, examinó una estrategia experimental como uno primero paso para una investigación sobre la inclusión de estímulos reforzadores como miembros de clases secuenciales. Su objetivo fue investigar el efecto de reforzadores condicionados específicos en la formación de clases ordinales. En la presencia de uno estímulo condicional, seis universitarios debían secuenciar figuras abstractas en una determinada orden, lo que seguia-se la apresentación de una pasaje musical. En la presencia de otro estímulo condicional, los mismos estímulos debían ser secuenciados, en la orden inversa, producindo otra pasaje musical. Testes evidenciaron que más adelante da emergencia de las propiedades definidoras de clases secuenciales, los pasajes musicales intercambiaron su función reforzadora para la de estímulos condicionales.

Assuntos

RESUMO

Resumen: El presente estudio evalúa el amaranto como una alternativa a los reforzadores que se utilizan en la actualidad en los laboratorios experimentales con roedores. Se compararon diversos elementos como la preferencia de consumo, la motivación y el valor reforzante entre tres tipos de alimentos (dos tipos de pellets y amaranto) mediante cuatro experimentos con laberinto radial y consumo libre en 11 ratas de la cepa Wistar. Los resultados muestran que el amaranto tiene un alto valor reforzante ya que, se observó preferencia por su consumo comparado con los demás alimentos. Se propone al amaranto como una buena alternativa para usarse como reforzador con varias ventajas como la preferencia de consumo, su valor reforzante, su fácil accesibilidad en el país y que es más económico que los pellets importados.

Abstract: This study evaluates amaranth as an alternative to reinforcers which are currently used in experimental laboratories with rodents. We compared some elements such as consumer preference, motivation and reinforcing value of three types of food (two types of pellets and amaranth) through four experiments with free radial maze and free consumption in 11 Wistar rats. The results show that amaranth has a high reinforcing value. Also, there was a preference for amaranth consumption compared with the other two reinforcers. Amaranth is proposed as a good alternative for use as a reinforcer with several advantages such as consumer preference, its reinforcing value, accessibility in the country and that it is cheaper than the usual pellets.

RESUMO

Este artigo descreve e analisa algumas articulações entre os conceitos de reforçadores arbitrários, reforçadores naturais, reforçadores imediatos - ou de curto prazo - e reforçadores de longo prazo encontrados na literatura, com vistas à sua específica utilização no delineamento de práticas culturais. Para tanto, os textos foram selecionados pela leitura dos títulos, resumos e palavras-chave. Realizada a seleção, os textos foram classificados, pela referência à articulação entre reforçadores. Foram selecionados 28 textos, dos quais 18 textos foram classificados como com referência à articulação. Considera-se que, embora as principais publicações da Análise do Comportamento revelem que esses princípios têm sido consistentemente estudados na pesquisa básica, apenas recentemente, em função da ampliação de projetos e intervenções ligadas à análise e planejamento cultural, tem sido revelada a necessidade de explorar verticalmente algumas de suas principais implicações teóricas e práticas.(AU)

This article describes and analyzes some links between the concepts of arbitrary reinforcers, natural reinforcers, immediate - or short-term reinforcers and long term reinforcers found in the literature, concerning its specific use in the design of cultural practices. Texts were selected reading the titles, abstracts and keywords. After selection, the texts were classified, as referring to the relationship between reinforcers. Twenty eight texts were selected, of which 18 were classified as texts with reference to the links. If was considered that, although the major publications of Behavior Analysis revealed that these principles have been consistently studied in basic research, only recently, due to the expansion of projects and interventions related to cultural analysis and planning, became important to explore vertically some of its main theoretical and practical implications.(AU)

Assuntos

RESUMO

Este artigo descreve e analisa algumas articulações entre os conceitos de reforçadores arbitrários, reforçadores naturais, reforçadores imediatos - ou de curto prazo - e reforçadores de longo prazo encontrados na literatura, com vistas à sua específica utilização no delineamento de práticas culturais. Para tanto, os textos foram selecionados pela leitura dos títulos, resumos e palavras-chave. Realizada a seleção, os textos foram classificados, pela referência à articulação entre reforçadores. Foram selecionados 28 textos, dos quais 18 textos foram classificados como com referência à articulação. Considera-se que, embora as principais publicações da Análise do Comportamento revelem que esses princípios têm sido consistentemente estudados na pesquisa básica, apenas recentemente, em função da ampliação de projetos e intervenções ligadas à análise e planejamento cultural, tem sido revelada a necessidade de explorar verticalmente algumas de suas principais implicações teóricas e práticas.

This article describes and analyzes some links between the concepts of arbitrary reinforcers, natural reinforcers, immediate - or short-term reinforcers and long term reinforcers found in the literature, concerning its specific use in the design of cultural practices. Texts were selected reading the titles, abstracts and keywords. After selection, the texts were classified, as referring to the relationship between reinforcers. Twenty eight texts were selected, of which 18 were classified as texts with reference to the links. If was considered that, although the major publications of Behavior Analysis revealed that these principles have been consistently studied in basic research, only recently, due to the expansion of projects and interventions related to cultural analysis and planning, became important to explore vertically some of its main theoretical and practical implications.

Assuntos

RESUMO

Para investigar como o tipo de reforçador afeta o comportamento em FI após diferentes histórias de reforço, universitários foram expostos a FR ou DRL, que liberavam pontos por pressionar um botão. Alguns participantes trocavam pontos por fotocópias (Condição 1), por dinheiro (Condição 2) ou apenas recebiam os pontos (Condição 3). Subseqüentemente, todos foram expostos a FI. O FR produziu taxas de respostas altas e constantes independentemente do tipo de reforçador utilizado. O FI produziu taxas altas para os participantes das Condições 1 e 2 e baixas para os participantes da Condição 3. O DRL produziu baixas taxas que aumentaram durante o FI subseqüente. Os resultados sugerem que tanto contingências históricas quanto presentes controlaram o comportamento dos participantes e que o tipo de reforçador pode favorecer o responder em taxa alta e constante sob FI após exposição a uma contingência de FR.

To investigate how the type of reinforcer affects the behavior in FI after different reinforcement histories, university students were exposed to FR or to DRL, that liberated points for pressing a button. Some participants changed points for photocopies (Condition 1), for money (Condition 2), or they just received the points (Condition 3). Subsequently, all students were exposed to FI. FR produced high and constant response rates independently of the type of reinforcer. FI produced high rates for the participants of the Conditions 1 and 2, and low for the participants of the Condition 3. DRL provoked low rates that increased during subsequent FI. The results suggest that so much historical contingencies as present contingencies controlled the participants' behavior and that the type of reinforcer can favor responding in high and constant rate under FI after a FR contingency.

Assuntos