When assessing preferences of individuals with developmental disabilities, choices can be described vocally or presented using objects or pictures in preference assessments. For individuals who are unable to perform auditory-visual discriminations and visual identity matching, objects instead of pictures or vocalizations need to be used for preference assessments to be effective. Considering the practical advantages of using pictures over objects, recent research has begun to focus on identifying and teaching skills needed for picture preference assessments. Although object-to-picture, picture-to-object, and generalized matching have been implicated as possible skills needed for picture preference assessments, further systematic studies are needed. The present study examined the relation between preference assessments (object vs. picture groups) and 5 discrimination skills. Based on direct paired-stimulus preference assessments completed at the beginning of the study, participants who could indicate their preferences with objects, but not with picture or vocal presentation, were assigned to the Object Group (n = 11); and participants who could indicate their preferences with both objects and pictures, but not vocal presentation, were assigned to the Picture Group (n = 9). The 5 discrimination tasks included: (a) object-picture matching and (b) its symmetry, picture-object matching; (c) generalized object-picture matching and (d) its symmetry, generalized picture-object matching; and (e) generalized identity picture-picture matching. All task stimuli were parts from everyday objects. Independent sample t-tests with Bonferroni correction showed that the percentages of correct responses were significantly higher in the Picture Group than in the Object Group on 4 of the 5 tasks (p < .01). Individual data showed that 8 of the 9 Picture Group participants met the pass criterion (80% or higher correct responses) on at least 1 discrimination task, with 6 participants passing 2 or more tasks. In contrast, only 1 of the 11 Object Group participants met the pass criterion on 1 discrimination task. The findings suggest that the effectiveness of picture preference assessments is not dependent on one specific discrimination, but possibly the ability to perform generalized matching.

When assessing preferences of individuals with developmental disabilities, choices can be described vocally or presented using objects or pictures in preference assessments. For individuals who are unable to perform auditory-visual discriminations and visual identity matching, objects instead of pictures or vocalizations need to be used for preference assessments to be effective. Considering the practical advantages of using pictures over objects, recent research has begun to focus on identifying and teaching skills needed for picture preference assessments. Although object-to-picture, picture-to-object, and generalized matching have been implicated as possible skills needed for picture preference assessments, further systematic studies are needed. The present study examined the relation between preference assessments (object vs. picture groups) and 5 discrimination skills. Based on direct paired-stimulus preference assessments completed at the beginning of the study, participants who could indicate their preferences with objects, but not with picture or vocal presentation, were assigned to the Object Group (n = 11); and participants who could indicate their preferences with both objects and pictures, but not vocal presentation, were assigned to the Picture Group (n = 9). The 5 discrimination tasks included: (a) object-picture matching and (b) its symmetry, picture-object matching; (c) generalized object-picture matching and (d) its symmetry, generalized picture-object matching; and (e) generalized identity picture-picture matching. All task stimuli were parts from everyday objects. Independent sample t-tests with Bonferroni correction showed that the percentages of correct responses were significantly higher in the Picture Group than in the Object Group on 4 of the 5 tasks (p < .01). Individual data showed that 8 of the 9 Picture Group participants met the pass criterion (80% or higher correct responses) on at least 1 discrimination task, with 6 participants passing 2 or more tasks. In contrast, only 1 of the 11 Object Group participants met the pass criterion on 1 discrimination task. The findings suggest that the effectiveness of picture preference assessments is not dependent on one specific discrimination, but possibly the ability to perform generalized matching.

O presente estudo investigou comportamentos simbólicos nos portadores de Síndrome de Apert por meio do paradigma da equivalência de estímulos, uma vez que este pode fornecer subsídios para a compreensão do comportamento humano complexo, tais como o comportamento simbólico e a linguagem. Foram propostos três experimentos cujos participantes, com idades entre 16 e 21 anos, foram submetidos aos Experimentos 1 e 2 (P1, P2 e P3) e submetidos ao Experimento 3 (P4 e P5). No Experimento 1, o objetivo foi verificar a formação de classes de estímulos equivalentes após o treino de relações condicionais, por meio de uma tarefa de matching to sample (MTS) com atraso de 0 s e três estímulos de comparação. Após o participante atingir um percentual de acerto de 94% no bloco, foram conduzidos testes de equivalência (CA), simetria (BA e CB) e transitividade (AC). De maneira geral, houve falha nos testes, com relativa preservação do teste de simetria. No Experimento 2, os participantes foram expostos à tarefa de MTS com atraso de 0 s e três estímulos de comparação, mas estes e o estímulo modelo apresentavam-se inicialmente cobertos, tornando-se visíveis somente após a emissão de respostas de observação (ROs). Foram introduzidas ROs na tarefa de MTS, com o objetivo de identificar que tipos de controle (seleção ou rejeição) poderiam estar em operação na formação de classes de estímulos equivalentes. Nos testes, o participante P3 formou classes de equivalência, contudo, os participantes P1 e P2 continuaram a apresentar falha na formação de equivalência, com preservação do teste de simetria. No Experimento 3, foram apresentadas variações metodológicas com o objetivo de favorecer o estabelecimento de um ou de outro tipo de controle (seleção ou rejeição), durante o treino das relações condicionais e verificar os efeitos destas variações no desempenho obtido nos testes. O participante P4 foi submetido primeiramente à situação na qual a terceira RO produzia o estímulo correto em 80% das tentativas (80%/3ª S+). Posteriormente 9 à realização das tarefas sob esta condição, foi submetido à situação na qual a primeira RO produzia o estímulo correto em 80% das tentativas (80%/1ª S+). O participante P5 foi exposto à ordem inversa: primeiramente à situação 80%/1ª S+ e posteriormente à situação 80%/3ª S+. Nos testes, em ambas as situações, o participante P4 foi capaz de aprender as relações de equivalência propostas pelo experimentador. Diferentemente, o responder do participante P5 não se apresentou sob controle discriminativo das contingências programadas pelo experimentador. De um modo geral, os resultados obtidos pelo presente estudo acrescidos das análises do teste PEABODY, sugerem que as dificuldades para a formação de classes de equivalência em participantes com baixo funcionamento lingüístico podem decorrer, em grande parte, de preparação e adaptação insuficiente de procedimentos para esse tipo de população / The present study investigated the symbolic behaviors of patients with Apert Syndrome through the paradigm of stimulus equivalence, since it may provide a basis for understanding complex human behavior, such as symbolic behavior and language. It had been proposed three experiments which participants, aged between 16 and 21 years, were submitted to Experiments 1 and 2 (P1, P2 and P3) and to Experiment 3 (P4 e P5). In Experiment 1, the objective was to assess the formation of classes of equivalent stimuli after training of conditional relations, through a task of matching to sample (MTS) and delay of 0s and three comparison stimuli. After the participant reaches a 94% criterion for accuracy in the block, tests were conducted for equivalence (CA), symmetry (BA and CB) and transitivity (AC). In general, the participants failed the tests, with relative preservation of the symmetry test. In Experiment 2, the participants were exposed to the task of MTS with delay of 0s and three comparison stimuli, but these and the sample stimulus were initially covered, becoming visible only after the observation responses (OR´s) issuance. ORs were introduced in the MTS task, with the objective to assess what kind of different controls (selection and rejection) could be involved in the formation of classes of equivalent stimuli. In tests, participant P3 showed the formation of classes of equivalent stimuli; however, participants P1 and P2 had failed to form equivalence, preserving the symmetry test. In Experiment 3 were presented methodological variations with the objective of encouraging the establishment of one or another type of control (selection or rejection) during the training of conditional relations and verify the effects of these variations in performance obtained in tests. Participant P4 was, at first, subjected to the situation which the third OR produced the correct stimulus in 80% of attempts (80% / 3rd S +). After the tasks under this condition were performed, P4 underwent a situation which the first OR produced the correct stimulus in 80% of attempts (80% / 1st S +). The participant P5 was exposed to the reverse order: first of all to the situation 80% / 1st S + and subsequently to the situation 80% / 3rd S +. In the tests, in both situations, the participant P4 was able to learn the equivalence 11 relations proposed by the experimenter. In contrast, the response of the participant P5 was not under discriminative control of the contingencies programmed by the experimenter. In general, the results obtained by this study plus the analysis of the PEABODY data suggests that difficulties in the formation of equivalence classes in participants with low language functioning may be due, in large part from inadequate preparation and adjustment procedures for this type of population

Treinos discriminativos específicos podem favorecer que um organismo responda consistentemente sob controle de relações entre estímulos que não foram diretamente ensinadas. Diz-se, então, que estas são relações emergentes. Caso tais relações estejam de acordo com as propriedades de reflexividade, simetria e transitividade, é constatada a formação de classes de estímulos equivalentes. Nas últimas décadas, diversos estudos vêm tentando demonstrar a formação de classes de estímulos equivalentes em animais não humanos, mas poucos têm tido sucesso. Dentre as propriedades definidoras da equivalência, a simetria tem sido a mais difícil de ser observada. Ao identificarem variáveis relacionadas aos resultados inconsistentes de estudos envolvendo testes de simetria, Frank e Wasserman (2005) planejaram um experimento com pombos, no qual tentativas de relações de identidade e arbitrárias eram apresentadas em uma mesma sessão, que resultou em desempenho positivo nos testes. O objetivo do presente trabalho foi identificar algumas das variáveis que possivelmente contribuíram para os resultados obtidos no referido estudo. Para tanto, foram realizados dois experimentos, com três pombos cada, para verificar: 1) a replicabilidade dos dados obtidos por Frank e Wasserman (2005); 2) se o treino de reversibilidade de combinações negativas é um fator importante na obtenção de simetria emergente com este procedimento. Os sujeitos foram ensinados a bicar estímulos apresentados isoladamente na tela de um computador em uma tarefa de matching sucessivo. O Experimento I consistiu no treino misto das relações AA, BB e AB e no teste de simetria BA. O Experimento II era semelhante ao anterior, exceto que, para que não ocorresse o treino de reversibilidade das combinações negativas, foram acrescentadas as relações CC no treino. Apenas dois pombos, um de cada experimento, apresentaram responder discriminado no treino. Ambos apresentaram desempenho semelhante ao do estudo de Frank e Wasserman (2005), o que indicaria emergência de simetria. Entretanto, uma análise mais detalhada do desempenho destes dois pombos revelou um responder instável entre as sessões de teste. Os outros quatro sujeitos não apresentaram responder discriminado apesar do elevado número de sessões (entre 65 e 220). A análise da distribuição das respostas ao longo do tempo de apresentação dos estímulos indicou diferenças entre o responder dos pombos que concluíram e que não concluíram o treino. Estes últimos apresentaram um responder marcado por longas pausas entre respostas, com menor freqüência de respostas para o estímulo modelo. Os pombos que concluíram a fase de treino apresentaram um responder constante, com poucas e curtas pausas, com maior freqüência de respostas diante do modelo do que diante dos estímulos de comparação. Os resultados dos testes de simetria indicam que o treino de reversão das combinações negativas não foi um fator relacionado à emergência de simetria com este procedimento. O fato de que a maioria dos sujeitos não aprendeu as relações treinadas, bem como os diferentes padrões de responder apresentados pelos sujeitos ao longo do treino e o desempenho instável nas sessões de teste, indicam a necessidade de refinamento do procedimento, buscando favorecer a aprendizagem e produzir estabilidade nos testes / Specific conditions in the discriminative training should set conditions for an organism to respond controlled by stimuli relations, not directly trained. These stimuli relations are said to be emergent. If these relations are reflexive, symmetric and transitive, than classes of equivalent stimuli were established. In the last decades, several studies tried to demonstrate the formation of equivalence classes in non-humans animals, but a few succeed. From among those properties that define equivalence relations, symmetry is the most hardly observed. Once identified some variables involved with the discrepant results in the symmetry tests, Frank and Wasserman (2005) designed an experiment with pigeons, where identity and arbitrary trials were presented altogether in the training sessions. This procedure resulted in positive outcomes in symmetry tests. The purpose in this study was to assess some of the variables that possibly contributed to Frank and Wassermans (2005) positive results. Two experiments were conducted in order to verify 1) Frank and Wasserman (2005) data replicability; 2) if training the negative combinations reversals is relevant in producing emergent symmetry by this procedure. Tree pigeons participated in each one of them. The pigeons were trained to peak stimuli presented alone in a computer screen in a successive matching task. Experiment I consisted in mixed training of AA, BB and AB relations followed by symmetry tests for BA relation. Experiment II was identical to the previous one, except that CC relations were added in order to avoid the negative relations reversal training. Only two pigeons, one of each experiment, reach training criterion. Their performances in symmetry tests were quite similar to those presented by Frank and Wasserman (2005) indicating that training resulted in symmetry relations. Meanwhile, a careful analysis of these symmetric performances in the testes revealed to be unstable from session to session. The four remaining pigeons did not reached training criterion despite of been exposed to high number of training sessions (about 65 to 220 sessions). Differences in distribution of responses over stimuli presentation interval were observed comparing data of the two pigeons that reached training criterion and pigeons that did not reach training criterion. Low frequency of response and long inter-response interval to the sample stimulus characterized the performances of the four pigeons whose training criterion has never been reached. For the pigeons whose training criterion was reached the responses occurred constantly, with few and short inter-responses intervals and high frequency of responding to the sample stimulus when compared to the comparison stimulus. The symmetry tests results suggests that training the negative combinations reversals did not affected the emergence of symmetric relations in this procedure. The fact that most of the pigeons did not reached training criterion, along with the different response patterns shown by each pigeon in the training task and the unstable performance observed in the tests indicates that procedure refining is needed in order to improve learning to criterion and produce stability during tests.

O procedimento de discriminação condicional Matching - to - Sample é utilizado em estudos que se propõem a investigar experimentalmente as relações envolvidas no ler e, mais especificamente, de verificar as possibilidades de emergência de novas relações a partir das que foram diretamente treinadas . No entanto, para uma leitura proficiente é necessário que o aprendiz esteja sob controle de unidades menores do que a palavra, a fim de que o comportamento de ler sob controle das unidades mínimas possa emergir. A maioria das pesquisas nesta área tem sido realizadas a partir do treino e teste recombinativo de palavras inteiras. A leitura sob controle das unidades mínimas, nestes estudos, é exibida geralmente depois do treino de pelo menos três conjuntos de palavras. O objetivo do presente trabalho foi investigar a possibilidade de um aumento na velocidade de aquisição do controle pelas unidades menores e redução da variabilidade no desempenho em leitura recombinativa partindo do treino direto de um repertório de quatro palavras monossilábicas. Foram feitos dois experimentos: no primeiro, participaram quatro crianças, com idades entre 3 anos e 10 meses e 5 anos. Os estímulos experimentais originais (conjunto ABC) foram NO, PE, PA e LU e os estímulos experimentais derivados (conjunto ABC) foram LUPA, PANO, PAPA e LULU. Os resultados demonstraram que os quatro participantes apresentaram variabilidade no desempenho e não houve emergência da leitura recombinativa para nenhum deles. Foi realizado então o segundo experimento a partir de manipulações de variáveis que possivelmente interferiram no desempenho dos participantes. Neste segundo experimento, participaram três crianças, das quatro que foram expostas ao experimento anterior. Os estímulos experimentais originais (conjunto ABC) foram BO, BA, LO e LA e os derivados (conjunto ABC) foram BOBA, BABO, LOLA e LALO. Como resultados, dois dos três participantes exibiram leitura recombinativa e a variabilidade no desempenho destes participantes se mostrou menor do que nos estudos anteriores. Concluiu-se desta forma, que a partição do estímulos é uma variável importante para a independência funcional das sílabas e posterior emergência da leitura recombinativa. Assim, o treino monossilábico se mostrou eficaz para aumentar a velocidade de aquisição e diminuir a variablidade no desempenho em leitura recombinativa para os participantes deste estudo. / The procedure of conditional discrimination Matching - to - Sample is used in studies that experimentally investigate the relationship involved in \"reading\" and, more specifically, examine the possibilities of emergence of new relationships from which they were directly trained. However for a proficient reading it is necessary to read under control of smaller units than the word, so that the reading behavior under the control by minimal units could emerge. The majority of researches in this area have been carried out with training and recombinative testing of the whole words. Reading behavior under control by the minimal units in these studies generally appears after the training of at least three sets of words. The objective of this study therefore was to investigate the possibility of an increase in speed of acquisition of control by smaller units and to reduce variabilitys performance in recombinative reading through the direct training of a repertoire of four monosyllabic words. Two experiments were conducted: in the first one, four children were from three years and ten months old to five years old. The originals experimental stimuli (all ABC) was NO, PE, PA and LU and the deriveds experimental stimuli (all A\'B\'C \') were LUPA, PANO, PAPA and LULU. The results showed that all four participants showed variability in performance and no emergence of recombinative reading . A second experiment were carried out withthe manipulation of variables that possibly interfered in the performance of the participants. In this second experiment three children were involved, four of which were exposed to the previous experiment. The original experimental stimuli (all ABC) were BO, BA, LA and LO and derived (all A\'B\'C \') were BABO, BOBA, LALO and LOLA. As a result, two of the three participants showed recombinative reading and the variability in performance of these participants wassmaller than in previous studies. The partition of the stimulus was considered an important variable for the functional independence of syllables and subsequent emergence of recombinative reading. Thus, the monosyllabic training was effective to increase the speed of acquisition and to reduce the variability in performance of recombinative reading for participants.

O procedimento de discriminação condicional Matching - to - Sample é utilizado em estudos que se propõem a investigar experimentalmente as relações envolvidas no ler e, mais especificamente, de verificar as possibilidades de emergência de novas relações a partir das que foram diretamente treinadas . No entanto, para uma leitura proficiente é necessário que o aprendiz esteja sob controle de unidades menores do que a palavra, a fim de que o comportamento de ler sob controle das unidades mínimas possa emergir. A maioria das pesquisas nesta área tem sido realizadas a partir do treino e teste recombinativo de palavras inteiras. A leitura sob controle das unidades mínimas, nestes estudos, é exibida geralmente depois do treino de pelo menos três conjuntos de palavras. O objetivo do presente trabalho foi investigar a possibilidade de um aumento na velocidade de aquisição do controle pelas unidades menores e redução da variabilidade no desempenho em leitura recombinativa partindo do treino direto de um repertório de quatro palavras monossilábicas. Foram feitos dois experimentos: no primeiro, participaram quatro crianças, com idades entre 3 anos e 10 meses e 5 anos. Os estímulos experimentais originais (conjunto ABC) foram NO, PE, PA e LU e os estímulos experimentais derivados (conjunto ABC) foram LUPA, PANO, PAPA e LULU. Os resultados demonstraram que os quatro participantes apresentaram variabilidade no desempenho e não houve emergência da leitura recombinativa para nenhum deles. Foi realizado então o segundo experimento a partir de manipulações de variáveis que possivelmente interferiram no desempenho dos participantes. Neste segundo experimento, participaram três crianças, das quatro que foram expostas ao experimento anterior. Os estímulos experimentais originais (conjunto ABC) foram BO, BA, LO e LA e os derivados (conjunto ABC) foram BOBA, BABO, LOLA e LALO. Como resultados, dois dos três participantes exibiram leitura recombinativa e a variabilidade no desempenho destes participantes se mostrou menor do que nos estudos anteriores. Concluiu-se desta forma, que a partição do estímulos é uma variável importante para a independência funcional das sílabas e posterior emergência da leitura recombinativa. Assim, o treino monossilábico se mostrou eficaz para aumentar a velocidade de aquisição e diminuir a variablidade no desempenho em leitura recombinativa para os participantes deste estudo. / The procedure of conditional discrimination Matching - to - Sample is used in studies that experimentally investigate the relationship involved in \"reading\" and, more specifically, examine the possibilities of emergence of new relationships from which they were directly trained. However for a proficient reading it is necessary to read under control of smaller units than the word, so that the reading behavior under the control by minimal units could emerge. The majority of researches in this area have been carried out with training and recombinative testing of the whole words. Reading behavior under control by the minimal units in these studies generally appears after the training of at least three sets of words. The objective of this study therefore was to investigate the possibility of an increase in speed of acquisition of control by smaller units and to reduce variabilitys performance in recombinative reading through the direct training of a repertoire of four monosyllabic words. Two experiments were conducted: in the first one, four children were from three years and ten months old to five years old. The originals experimental stimuli (all ABC) was NO, PE, PA and LU and the deriveds experimental stimuli (all A\'B\'C \') were LUPA, PANO, PAPA and LULU. The results showed that all four participants showed variability in performance and no emergence of recombinative reading . A second experiment were carried out withthe manipulation of variables that possibly interfered in the performance of the participants. In this second experiment three children were involved, four of which were exposed to the previous experiment. The original experimental stimuli (all ABC) were BO, BA, LA and LO and derived (all A\'B\'C \') were BABO, BOBA, LALO and LOLA. As a result, two of the three participants showed recombinative reading and the variability in performance of these participants wassmaller than in previous studies. The partition of the stimulus was considered an important variable for the functional independence of syllables and subsequent emergence of recombinative reading. Thus, the monosyllabic training was effective to increase the speed of acquisition and to reduce the variability in performance of recombinative reading for participants.

Treinos discriminativos específicos podem favorecer que um organismo responda consistentemente sob controle de relações entre estímulos que não foram diretamente ensinadas. Diz-se, então, que estas são relações emergentes. Caso tais relações estejam de acordo com as propriedades de reflexividade, simetria e transitividade, é constatada a formação de classes de estímulos equivalentes. Nas últimas décadas, diversos estudos vêm tentando demonstrar a formação de classes de estímulos equivalentes em animais não humanos, mas poucos têm tido sucesso. Dentre as propriedades definidoras da equivalência, a simetria tem sido a mais difícil de ser observada. Ao identificarem variáveis relacionadas aos resultados inconsistentes de estudos envolvendo testes de simetria, Frank e Wasserman (2005) planejaram um experimento com pombos, no qual tentativas de relações de identidade e arbitrárias eram apresentadas em uma mesma sessão, que resultou em desempenho positivo nos testes. O objetivo do presente trabalho foi identificar algumas das variáveis que possivelmente contribuíram para os resultados obtidos no referido estudo. Para tanto, foram realizados dois experimentos, com três pombos cada, para verificar: 1) a replicabilidade dos dados obtidos por Frank e Wasserman (2005); 2) se o treino de reversibilidade de combinações negativas é um fator importante na obtenção de simetria emergente com este procedimento. Os sujeitos foram ensinados a bicar estímulos apresentados isoladamente na tela de um computador em uma tarefa de matching sucessivo. O Experimento I consistiu no treino misto das relações AA, BB e AB e no teste de simetria BA. O Experimento II era semelhante ao anterior, exceto que, para que não ocorresse o treino de reversibilidade das combinações negativas, foram acrescentadas as relações CC no treino. Apenas dois pombos, um de cada experimento, apresentaram responder discriminado no treino. Ambos apresentaram desempenho semelhante ao do estudo de Frank e Wasserman (2005), o que indicaria emergência de simetria. Entretanto, uma análise mais detalhada do desempenho destes dois pombos revelou um responder instável entre as sessões de teste. Os outros quatro sujeitos não apresentaram responder discriminado apesar do elevado número de sessões (entre 65 e 220). A análise da distribuição das respostas ao longo do tempo de apresentação dos estímulos indicou diferenças entre o responder dos pombos que concluíram e que não concluíram o treino. Estes últimos apresentaram um responder marcado por longas pausas entre respostas, com menor freqüência de respostas para o estímulo modelo. Os pombos que concluíram a fase de treino apresentaram um responder constante, com poucas e curtas pausas, com maior freqüência de respostas diante do modelo do que diante dos estímulos de comparação. Os resultados dos testes de simetria indicam que o treino de reversão das combinações negativas não foi um fator relacionado à emergência de simetria com este procedimento. O fato de que a maioria dos sujeitos não aprendeu as relações treinadas, bem como os diferentes padrões de responder apresentados pelos sujeitos ao longo do treino e o desempenho instável nas sessões de teste, indicam a necessidade de refinamento do procedimento, buscando favorecer a aprendizagem e produzir estabilidade nos testes / Specific conditions in the discriminative training should set conditions for an organism to respond controlled by stimuli relations, not directly trained. These stimuli relations are said to be emergent. If these relations are reflexive, symmetric and transitive, than classes of equivalent stimuli were established. In the last decades, several studies tried to demonstrate the formation of equivalence classes in non-humans animals, but a few succeed. From among those properties that define equivalence relations, symmetry is the most hardly observed. Once identified some variables involved with the discrepant results in the symmetry tests, Frank and Wasserman (2005) designed an experiment with pigeons, where identity and arbitrary trials were presented altogether in the training sessions. This procedure resulted in positive outcomes in symmetry tests. The purpose in this study was to assess some of the variables that possibly contributed to Frank and Wassermans (2005) positive results. Two experiments were conducted in order to verify 1) Frank and Wasserman (2005) data replicability; 2) if training the negative combinations reversals is relevant in producing emergent symmetry by this procedure. Tree pigeons participated in each one of them. The pigeons were trained to peak stimuli presented alone in a computer screen in a successive matching task. Experiment I consisted in mixed training of AA, BB and AB relations followed by symmetry tests for BA relation. Experiment II was identical to the previous one, except that CC relations were added in order to avoid the negative relations reversal training. Only two pigeons, one of each experiment, reach training criterion. Their performances in symmetry tests were quite similar to those presented by Frank and Wasserman (2005) indicating that training resulted in symmetry relations. Meanwhile, a careful analysis of these symmetric performances in the testes revealed to be unstable from session to session. The four remaining pigeons did not reached training criterion despite of been exposed to high number of training sessions (about 65 to 220 sessions). Differences in distribution of responses over stimuli presentation interval were observed comparing data of the two pigeons that reached training criterion and pigeons that did not reach training criterion. Low frequency of response and long inter-response interval to the sample stimulus characterized the performances of the four pigeons whose training criterion has never been reached. For the pigeons whose training criterion was reached the responses occurred constantly, with few and short inter-responses intervals and high frequency of responding to the sample stimulus when compared to the comparison stimulus. The symmetry tests results suggests that training the negative combinations reversals did not affected the emergence of symmetric relations in this procedure. The fact that most of the pigeons did not reached training criterion, along with the different response patterns shown by each pigeon in the training task and the unstable performance observed in the tests indicates that procedure refining is needed in order to improve learning to criterion and produce stability during tests.

O presente estudo investigou comportamentos simbólicos nos portadores de Síndrome de Apert por meio do paradigma da equivalência de estímulos, uma vez que este pode fornecer subsídios para a compreensão do comportamento humano complexo, tais como o comportamento simbólico e a linguagem. Foram propostos três experimentos cujos participantes, com idades entre 16 e 21 anos, foram submetidos aos Experimentos 1 e 2 (P1, P2 e P3) e submetidos ao Experimento 3 (P4 e P5). No Experimento 1, o objetivo foi verificar a formação de classes de estímulos equivalentes após o treino de relações condicionais, por meio de uma tarefa de matching to sample (MTS) com atraso de 0 s e três estímulos de comparação. Após o participante atingir um percentual de acerto de 94% no bloco, foram conduzidos testes de equivalência (CA), simetria (BA e CB) e transitividade (AC). De maneira geral, houve falha nos testes, com relativa preservação do teste de simetria. No Experimento 2, os participantes foram expostos à tarefa de MTS com atraso de 0 s e três estímulos de comparação, mas estes e o estímulo modelo apresentavam-se inicialmente cobertos, tornando-se visíveis somente após a emissão de respostas de observação (ROs). Foram introduzidas ROs na tarefa de MTS, com o objetivo de identificar que tipos de controle (seleção ou rejeição) poderiam estar em operação na formação de classes de estímulos equivalentes. Nos testes, o participante P3 formou classes de equivalência, contudo, os participantes P1 e P2 continuaram a apresentar falha na formação de equivalência, com preservação do teste de simetria. No Experimento 3, foram apresentadas variações metodológicas com o objetivo de favorecer o estabelecimento de um ou de outro tipo de controle (seleção ou rejeição), durante o treino das relações condicionais e verificar os efeitos destas variações no desempenho obtido nos testes. O participante P4 foi submetido primeiramente à situação na qual a terceira RO produzia o estímulo correto em 80% das tentativas (80%/3ª S+). Posteriormente 9 à realização das tarefas sob esta condição, foi submetido à situação na qual a primeira RO produzia o estímulo correto em 80% das tentativas (80%/1ª S+). O participante P5 foi exposto à ordem inversa: primeiramente à situação 80%/1ª S+ e posteriormente à situação 80%/3ª S+. Nos testes, em ambas as situações, o participante P4 foi capaz de aprender as relações de equivalência propostas pelo experimentador. Diferentemente, o responder do participante P5 não se apresentou sob controle discriminativo das contingências programadas pelo experimentador. De um modo geral, os resultados obtidos pelo presente estudo acrescidos das análises do teste PEABODY, sugerem que as dificuldades para a formação de classes de equivalência em participantes com baixo funcionamento lingüístico podem decorrer, em grande parte, de preparação e adaptação insuficiente de procedimentos para esse tipo de população / The present study investigated the symbolic behaviors of patients with Apert Syndrome through the paradigm of stimulus equivalence, since it may provide a basis for understanding complex human behavior, such as symbolic behavior and language. It had been proposed three experiments which participants, aged between 16 and 21 years, were submitted to Experiments 1 and 2 (P1, P2 and P3) and to Experiment 3 (P4 e P5). In Experiment 1, the objective was to assess the formation of classes of equivalent stimuli after training of conditional relations, through a task of matching to sample (MTS) and delay of 0s and three comparison stimuli. After the participant reaches a 94% criterion for accuracy in the block, tests were conducted for equivalence (CA), symmetry (BA and CB) and transitivity (AC). In general, the participants failed the tests, with relative preservation of the symmetry test. In Experiment 2, the participants were exposed to the task of MTS with delay of 0s and three comparison stimuli, but these and the sample stimulus were initially covered, becoming visible only after the observation responses (OR´s) issuance. ORs were introduced in the MTS task, with the objective to assess what kind of different controls (selection and rejection) could be involved in the formation of classes of equivalent stimuli. In tests, participant P3 showed the formation of classes of equivalent stimuli; however, participants P1 and P2 had failed to form equivalence, preserving the symmetry test. In Experiment 3 were presented methodological variations with the objective of encouraging the establishment of one or another type of control (selection or rejection) during the training of conditional relations and verify the effects of these variations in performance obtained in tests. Participant P4 was, at first, subjected to the situation which the third OR produced the correct stimulus in 80% of attempts (80% / 3rd S +). After the tasks under this condition were performed, P4 underwent a situation which the first OR produced the correct stimulus in 80% of attempts (80% / 1st S +). The participant P5 was exposed to the reverse order: first of all to the situation 80% / 1st S + and subsequently to the situation 80% / 3rd S +. In the tests, in both situations, the participant P4 was able to learn the equivalence 11 relations proposed by the experimenter. In contrast, the response of the participant P5 was not under discriminative control of the contingencies programmed by the experimenter. In general, the results obtained by this study plus the analysis of the PEABODY data suggests that difficulties in the formation of equivalence classes in participants with low language functioning may be due, in large part from inadequate preparation and adjustment procedures for this type of population

The purpose of this study was to develop behavior by the pigeon illustrative of S+ and S- rules and to examine if behavior consistent with a concept rule interpretation developed. In order to examine this possibility six groups of pigeons (N=31) were provided different histories of autoshaping. Histories involved the identity of the color of the lighted center key and one side key of three horizontally mounted pigeon keys. Center key onset was followed three seconds later by onset of either outer key. Outer key onset was followed six seconds later by food presentation (explicitly paired) or 45 seconds later, during the inter-trial interval (explicitly unpaired). The foregoing reinforcement conditions were factored into two stimulus conditions, one where the center and side keys were lit by the same hue (identity) and one where the center and side key were lit by different hues (nonidentity). Two groups received identity stimulus sequences with explicitly unpaired food presentation. Two groups were exposed to nonidentity stimulus sequences with explicitly unpaired food presentation. One group received sessions combining exposure to both the explicitly paired identity and explicitly unpaired nonidentity trials. One group received no pretraining. Following pretraining, all birds were placed in a simultaneous matching-to-sample task utilizing the same hues used during pretraining. After reaching criterion on matching-to-sample, on a random ratio 3 schedule of reinforcement, birds were exposed to transfer tests, with a novel hue, to assess for S+ rules, S- rules, and a concept rule. The results indicated that there were no significant differences among groups in terms of their acquisition of matching-to-sample or in terms of their performance on transfer tests. All birds' responding during transfer conditions provided evidence of S+ rules, but neither demonstration of S- rules nor concept rule performance was evidenced. During autoshaping, birds in the identity, explicitly paired groups responded primarily to the center key, suggesting that the stimulus on the outer key was not a salient stimulus for the identity discrimination. For birds in the nonidentity, explicitly unpaired groups neither the center nor outer key controlled responding. For the group combining identity, explicitly paired and nonidentity, explicitly unpaired trials, the birds failed to form a discrimination between types of trials.

Stimulus Pairing Observational Procedure (SPOP) is an incidental teaching type procedure that has shown success in teaching typically developing children to name, independent tacting in the absence of the verbal community following a history of listener and echoic responses. The purpose of the current study was to compare SPOP and matching to sample procedures to determine the rate of acquisition for correct tact and listener responding , the rate of off task be avior, and the rate of generalization to different settings, stimuli, and instructors. Results of the study indicate that correct responding occurred at higher rates during MTS procedures than SPOP. The average rate of off task behavior was higher during SPOP sessions than during pre test, MTS sessions, or generalization probes for each participant. The results of the generalization probe may indicate that SPOP produces correct responding that increases or maintains during generalization, while MTS procedures produced more variable results.