Subchronic effects of fluoxetine on conditioned suppression produced by a hot air blast

Conditioned suppression is an animal model of anxiety disorders that has been broadly used to investigate the behavioral effects of different drugs. However, various methodological variables (e.g., the type of aversive stimulus) that supposedly interfere with the acquisition of conditioned suppression may also contribute to conflicting results among the studied drugs. Additionally, few studies have sought to investigate the effects of selective serotonin reuptake inhibitors (SSRIs). The present study investigated the effect of subchronic 5-day administration of 5 mg/kg fluoxetine in the retention of conditioned suppression produced by a hot air blast (HAB). The subjects were 12 albino Wistar rats distributed into an Experimental Group (EG) and Control Group (CG). After sessions were conducted to pair two stimuli, a sound and HAB, fluoxetine (EG) or saline (CG) was administered. Twenty-four hours after the last injection, a test session was conducted. The results showed no difference between groups. Fluoxetine (5 mg/kg) did not exert anxiolytic effects in this model of conditioned suppression produced by a HAB.

Aprendizagem ostensiva, comportamento de ouvinte e transferência de função por pareamento de estímulos / Ostensive learning, listener behavior, and function transfer by stimulus pairing

Skinner ao definir comportamento verbal em 1957 exclui o comportamento do ouvinte desta categoria. No entanto, alguns autores como Horne e Lowe e Stemmer sugerem que o comportamento de ouvinte pode ser condição necessária para aquisição do comportamento verbal. Stemmer propõe que o comportamento de ouvinte se dá através de aprendizagem ostensiva, aprendizagem que ocorre por pareamento de estímulos, semelhante à pavloviana, e que uma vez adquirido pode ser transferido para o de falante e reforçado diferencialmente. O presente trabalho irá sugerir semelhanças entre as propostas de Stemmer e o que Pavlov chamou de Segundo Sistema de Sinais, discutindo evidências empíricas sobre transferência de função de estímulos tanto em não-humanos como em humanos na literatura experimental. Apontará a viabilidade das propostas teóricas de Pavlov e Stemmer para ajudar a esclarecer os processos comportamentais subjacentes à área de equivalência de estímulos.

Skinner defining verbal behavior in 1957 excludes the behavior of listener from this category, however, some authors such as Horne and Lowe and also Stemmer suggest that the behavior of listener can be a prerequisite for the acquisition of verbal behavior. Stemmer suggests that the behavior of listener is given by ostensive learning, a pavlovian learning that occurs by pairing of stimuli, and once acquired can be transferred to the behavior of speaker and differentially reinforced. This paper will suggest some similarities between the Stemmer's approach to what Pavlov called Second Signal System, discussing empirical evidence on the function transference of stimuli in nonhumans and humans in the experimental literature. It will point out to the viability of the Pavlov and Stemmer's theoretical approach to clarify the behavioral processes underlying the stimulus equivalence studies.