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Research paper thumbnail of Comportamento coordenado e individual em duplas de ratos sob esquema de intervalo variável

XXVII CIC e XII CIDTI, Feb 25, 2021

Research paper thumbnail of Cooperative responding in rats: II. Performance on fixed-ratio schedules of mutual reinforcement

Journal of the experimental analysis of behavior, 2020

Coordinated responses of 5 dyads of rats were investigated under fixed-ratio (FR) schedules of mu... more Coordinated responses of 5 dyads of rats were investigated under fixed-ratio (FR) schedules of mutual water reinforcement. Coordinated responding was defined as 2 consecutive lever-presses, 1 from each of 2 rats, occurring <.5 s apart. In the FR schedules, each coordinated episode was defined as 1 response in the FR sequence. The size of FR schedules was parametrically manipulated assuming the values of FR 1, 6, 12, 18, 24, 30, 50, and 9, in this order. Each FR remained in effect until responding reached stability. Under all conditions, pairs of rats received access to water simultaneously (mutual reinforcement). Rates and proportions of coordinated responding showed a bitonic inverted U-shaped function of ratio size. Postreinforcement pauses increased systematically as the interreinforcement interval increased. Local rates and proportions increased as a function of response location within ratios. Results of a control condition with relaxed temporal constraints for mutual reinfo...

Research paper thumbnail of Supressão Condicionada Discriminada Em Ratos: Em Busca De Replicação

Revista Brasileira de Análise do Comportamento

No procedimento de supressão condicionada um pareamento entre um estímulo neutro e um estímulo av... more No procedimento de supressão condicionada um pareamento entre um estímulo neutro e um estímulo aversivo é sobreposto a uma linha de base de comportamento operante. O pareamento resulta em supressão do responder durante o estímulo aversivo condicionado e sua recuperação após a ocorrência do estímulo aversivo incondicionado. Este trabalho teve como objetivo replicar estudo prévio que mostrou que os efeitos supressivos do pareamento ficaram parcialmente sob controle do estímulo discriminativo. Diferentemente do estudo anterior, a presente pesquisa utilizou contrabalanceamento do componente pareado entre sujeitos. Foi empregada uma linha de base de esquemas múltiplos de intervalos variáveis (mult VI VI) iguais, correlacionados com a presença ou a ausência de luz (componente claro/escuro). O procedimento seguiu um delineamento de reversão ABAC, em que A era a linha de base, o pareamento tom-choque foi introduzido somente em um dos componentes em B e em C o tom era apresentado sem o choqu...

Research paper thumbnail of Effects of Response-Reinforcer Relations on the Maintenance of Coordinated Responding Under Schedules of Simultaneous Reinforcement

Mexican journal of behaviour analysis, Dec 1, 2019

The effects of response-reinforcer relations on coordinated responding were investigated. Coordin... more The effects of response-reinforcer relations on coordinated responding were investigated. Coordinated responding was defined as two lever presses, one by each rat that occurred within 500 ms of one another. Four conditions were arranged in an ABCB design. Coordinated responding was reinforced according to a fixed-ratio 6 (FR 6) schedule in Condition A. In Condition B, a response by each rat was required, independent of their temporal proximity, to produce water delivery under a variable-interval schedule. Condition C was a replication of Condition B, except that coordinated responding was required for reinforcer deliveries. All conditions involved simultaneous reinforcement, that is the rats received access to reinforcers at the same time. The results extended previous findings by demonstrating that the requirement of coordinated responses to produce reinforcement affected both coordinated response rates and the proportion of such responses relative to the total responses in a session, in that both measures were higher in Conditions A and C than in Condition B. There also was control of the temporal distribution of coordinated responding by the type of schedule (FR or VI): A "break-and-run" pattern was observed under the FR schedule, and a constant response rate was observed under the VI schedule.

Research paper thumbnail of Learning a foreign language: Effects of tact and listener instruction on the emergence of bidirectional intraverbals

Journal of Applied Behavior Analysis

We evaluated the effects of tact and listener instruction on the emergence of bidirectional intra... more We evaluated the effects of tact and listener instruction on the emergence of bidirectional intraverbal relations with 6 typically developing Brazilian children, using an adapted alternating treatment design with pretest and posttest probes. In listener instruction, participants selected pictures that corresponded to spoken foreign-language words. For tact instruction, children had to vocalize foreign words in the presence of the corresponding pictures. After meeting mastery criteria, bidirectional intraverbal tests assessed vocalizations in Portuguese (native language) following the presentation of the equivalent words in English (foreign language) and vice versa. Tact instruction consistently produced higher levels of emergent intraverbal responding compared to listener instruction, confirming results from previous studies.

Research paper thumbnail of Cooperative responding in rats maintained by fixed- and variable-ratio schedules

Journal of the experimental analysis of behavior, Jan 29, 2018

The present study investigated the effects of fixed-ratio (FR) and variable-ratio (VR) reinforcem... more The present study investigated the effects of fixed-ratio (FR) and variable-ratio (VR) reinforcement schedules on patterns of cooperative responding in pairs of rats. Experiment 1 arranged FR 1, FR 10, and VR 10 schedules to establish cooperative responding (water delivery depended on the joint responding of two rats). Cooperative response rates and proportions were higher under intermittent schedules than under continuous reinforcement. The FR 10 schedule generated a break-and-run pattern, whereas the VR 10 schedule generated a relatively high and constant rate pattern. Experiment 2 evaluated the effects of parametric manipulations of FR and VR schedules on cooperative responding. Rates and proportions of cooperative responding generally increased between ratio sizes of 1 and 5 but showed no consistent trend as the ratio increased from 5 to 10. Experiment 3 contrasted cooperative responding between an FR6 schedule and a yoked control schedule. Coordinated behavior occurred at a hig...

Research paper thumbnail of Comportamento coordenado e individual em duplas de ratos sob esquema de intervalo variável

XXVII CIC e XII CIDTI, Feb 25, 2021

Research paper thumbnail of Cooperative responding in rats: II. Performance on fixed-ratio schedules of mutual reinforcement

Journal of the experimental analysis of behavior, 2020

Coordinated responses of 5 dyads of rats were investigated under fixed-ratio (FR) schedules of mu... more Coordinated responses of 5 dyads of rats were investigated under fixed-ratio (FR) schedules of mutual water reinforcement. Coordinated responding was defined as 2 consecutive lever-presses, 1 from each of 2 rats, occurring <.5 s apart. In the FR schedules, each coordinated episode was defined as 1 response in the FR sequence. The size of FR schedules was parametrically manipulated assuming the values of FR 1, 6, 12, 18, 24, 30, 50, and 9, in this order. Each FR remained in effect until responding reached stability. Under all conditions, pairs of rats received access to water simultaneously (mutual reinforcement). Rates and proportions of coordinated responding showed a bitonic inverted U-shaped function of ratio size. Postreinforcement pauses increased systematically as the interreinforcement interval increased. Local rates and proportions increased as a function of response location within ratios. Results of a control condition with relaxed temporal constraints for mutual reinfo...

Research paper thumbnail of Supressão Condicionada Discriminada Em Ratos: Em Busca De Replicação

Revista Brasileira de Análise do Comportamento

No procedimento de supressão condicionada um pareamento entre um estímulo neutro e um estímulo av... more No procedimento de supressão condicionada um pareamento entre um estímulo neutro e um estímulo aversivo é sobreposto a uma linha de base de comportamento operante. O pareamento resulta em supressão do responder durante o estímulo aversivo condicionado e sua recuperação após a ocorrência do estímulo aversivo incondicionado. Este trabalho teve como objetivo replicar estudo prévio que mostrou que os efeitos supressivos do pareamento ficaram parcialmente sob controle do estímulo discriminativo. Diferentemente do estudo anterior, a presente pesquisa utilizou contrabalanceamento do componente pareado entre sujeitos. Foi empregada uma linha de base de esquemas múltiplos de intervalos variáveis (mult VI VI) iguais, correlacionados com a presença ou a ausência de luz (componente claro/escuro). O procedimento seguiu um delineamento de reversão ABAC, em que A era a linha de base, o pareamento tom-choque foi introduzido somente em um dos componentes em B e em C o tom era apresentado sem o choqu...

Research paper thumbnail of Effects of Response-Reinforcer Relations on the Maintenance of Coordinated Responding Under Schedules of Simultaneous Reinforcement

Mexican journal of behaviour analysis, Dec 1, 2019

The effects of response-reinforcer relations on coordinated responding were investigated. Coordin... more The effects of response-reinforcer relations on coordinated responding were investigated. Coordinated responding was defined as two lever presses, one by each rat that occurred within 500 ms of one another. Four conditions were arranged in an ABCB design. Coordinated responding was reinforced according to a fixed-ratio 6 (FR 6) schedule in Condition A. In Condition B, a response by each rat was required, independent of their temporal proximity, to produce water delivery under a variable-interval schedule. Condition C was a replication of Condition B, except that coordinated responding was required for reinforcer deliveries. All conditions involved simultaneous reinforcement, that is the rats received access to reinforcers at the same time. The results extended previous findings by demonstrating that the requirement of coordinated responses to produce reinforcement affected both coordinated response rates and the proportion of such responses relative to the total responses in a session, in that both measures were higher in Conditions A and C than in Condition B. There also was control of the temporal distribution of coordinated responding by the type of schedule (FR or VI): A "break-and-run" pattern was observed under the FR schedule, and a constant response rate was observed under the VI schedule.

Research paper thumbnail of Learning a foreign language: Effects of tact and listener instruction on the emergence of bidirectional intraverbals

Journal of Applied Behavior Analysis

We evaluated the effects of tact and listener instruction on the emergence of bidirectional intra... more We evaluated the effects of tact and listener instruction on the emergence of bidirectional intraverbal relations with 6 typically developing Brazilian children, using an adapted alternating treatment design with pretest and posttest probes. In listener instruction, participants selected pictures that corresponded to spoken foreign-language words. For tact instruction, children had to vocalize foreign words in the presence of the corresponding pictures. After meeting mastery criteria, bidirectional intraverbal tests assessed vocalizations in Portuguese (native language) following the presentation of the equivalent words in English (foreign language) and vice versa. Tact instruction consistently produced higher levels of emergent intraverbal responding compared to listener instruction, confirming results from previous studies.

Research paper thumbnail of Cooperative responding in rats maintained by fixed- and variable-ratio schedules

Journal of the experimental analysis of behavior, Jan 29, 2018

The present study investigated the effects of fixed-ratio (FR) and variable-ratio (VR) reinforcem... more The present study investigated the effects of fixed-ratio (FR) and variable-ratio (VR) reinforcement schedules on patterns of cooperative responding in pairs of rats. Experiment 1 arranged FR 1, FR 10, and VR 10 schedules to establish cooperative responding (water delivery depended on the joint responding of two rats). Cooperative response rates and proportions were higher under intermittent schedules than under continuous reinforcement. The FR 10 schedule generated a break-and-run pattern, whereas the VR 10 schedule generated a relatively high and constant rate pattern. Experiment 2 evaluated the effects of parametric manipulations of FR and VR schedules on cooperative responding. Rates and proportions of cooperative responding generally increased between ratio sizes of 1 and 5 but showed no consistent trend as the ratio increased from 5 to 10. Experiment 3 contrasted cooperative responding between an FR6 schedule and a yoked control schedule. Coordinated behavior occurred at a hig...