RESUMO

In the basic verbal task from Piaget, when a relation of the form if A > B and B > C is given, a logical inference A > C is expected. This process is called transitive inference (TI). The adapted version for animals involves the presentation of a simultaneous discrimination between stimuli pairs. In this way, when A+B-, B+C-, C+D-, D+E- is trained, a B>D preference is expected, assuming that if A>B>C>D>E, then B>D. This effect has been widely reported using several procedures and different species. In the current experiment TI was evaluated employing probabilistic reinforcement. Thus, for the positive stimuli a .7 probability was administered and for the negative stimuli a .3 probability was administered. Under this arrangement the relation A>B>C>D>E is still allowed, but TI becomes more difficult. Five pigeons (Columba Livia) were exposed to the mentioned arrangement. Only one pigeon reached the criterion in C+D- discrimination, whereas the remaining did not. Only the one who successfully solved C+D- was capable of learning TI, whereas the others were not. Additionally, it was found that correct response ratios did not predict BD performance. Consequently, probabilistic reinforcement disrupted TI, but some positional ordering was retained in the test. The results suggest that TI might be affected by associative strength but also by the positional ordering of the stimuli. The discussion addresses the two main accounts of TI: the associative account and the ordinal representation account.

RESUMO

In propositional logic, it is stated that "for if A is predicated for every B, and B for every C, A must necessarily be predicated of every C". Following a similar logical process, it can be said that If A > B and B > C, then A > C, this is called transitive inference (TI). Piaget developed a verbal task to evaluate TI in children. Subsequent studies adapted this task for animals using a conditioned discrimination between five-terms sequence of stimuli A + B-, B + C-, C + D-, and D + E-. If subjects prefer B over D during test, it is assumed that TI has occurred. In this experiment, we analyzed the effects of task complexity on TI by using a five-terms sequence of stimuli associated with probabilistic outcomes during training, in pigeons. Thus, both stimuli are reinforced in each pair but with different probability, 0.8 for + stimulus and 0.2 for the-stimulus. We found that performance during C + D- pair is impaired and preference in the test pair BD is affected. However, this impairment is dependent on individual differences in performance in C + D- pair. We compare our findings with previous research and conclude that Pavlovian mechanisms, as well as ordering of stimuli, can account for our findings.

RESUMO

[This corrects the article DOI: 10.3389/fpsyg.2018.01791.].

RESUMO

Transitive inference (TI) has been studied in humans and several animals such as rats, pigeons and fishes. Using different methods for training premises it has been shown that a non-trained relation between stimuli can be stablished, so that if A > B > C > D > E, then B > D. Despite the widely reported cases of TI, the specific mechanisms underlying this phenomenon remain under discussion. In the present experiment pigeons were trained in a TI procedure with four premises. After being exposed to all premises, the pigeons showed a consistent preference for B over D during the test. After overtraining C+D- alone, B was still preferred over D. However, the expected pattern of training performance (referred to as serial position effect) was distorted, whereas TI remained unaltered. The results are discussed regarding value transfer and reinforcement contingencies as possible mechanisms. We conclude that reinforcement contingencies can affect training performance without altering TI.

RESUMO

BACKGROUND: A modified theory of planned behaviour (acronym CASCADA) proposes that Conscious knowledge precedes a change in Attitude, which in turn precedes positive deviations from negative Subjective norms, intention to Change, perception of Agency to change, Discussion of possible action, and Action itself. We used this as a results chain to investigate gender-specific behaviour dynamics in chemical-free dengue prevention. METHODS: Secondary analysis of the Mexican arm of a cluster randomised controlled trial used household survey data on intermediate outcomes of dengue prevention behaviour. We used a matrix of odds ratios between outcomes, transformed to a symmetrical range (-1, 1), to compute fuzzy transitive closure of the results chain for control and intervention clusters, then for male and female respondents separately in each group. Transitive closure of a map computes the influence of each factor on each other factor, taking account of all influences in the system. Cumulative net influence was the sum of influences across the results chain. RESULTS: Responses of 5042 women and 1143 men in 45 intervention clusters contrasted with those of 5025 women and 1179 men in 45 control clusters. Control clusters showed a distal block (negative influence) in the results chain with a cumulative net influence of 0.88; intervention clusters showed no such block and a cumulative net influence of 1.92. Female control respondents, like the overall control picture, showed a distal block, whereas female intervention responses showed no such blocks (cumulative net influence 0.78 and 1.73 respectively). Male control respondents showed weak distal blocks. Male intervention responses showed several new negative influences and a reduction of cumulative net influence (1.38 in control and 1.11 in intervention clusters). CONCLUSIONS: The overall influence of the intervention across the results chain fits with the trial findings, but is different for women and men. Among women, the intervention overcame blocks and increased the cumulative net influence of knowledge on action. Among men, the intervention did not reinforce prevention behaviour. This might be related to emphasis, during the intervention, on women's participation and empowerment. The fuzzy transitive closure of the CASCADA map usefully highlights the differences between gender-specific results chains. TRIAL REGISTRATION: ISRCTN27581154 .

Assuntos

RESUMO

Complex movement (CM) refers to the representation of a goal-oriented action and is classified as either transitive (use of tools) or intransitive (communication gestures). Both types of CM have three specific components: temporal, spatial, and content, which are subdivided into specific error types (SET). Since there is debate regarding the contribution of each brain hemisphere for the types of CM, our objective was to describe the brain lateralization of components and SET of transitive and intransitive CM. We studied 14 patients with a left hemisphere stroke (LH), 12 patients with a right hemisphere stroke (RH), and 16 control subjects. The Florida Apraxia Screening Test-Revised (FAST-R, Rothi et al., 1988) was used for the assessment of CM. Both clinical groups showed a worse performance than the control group on the total FAST-R and transitive movement scores (p<0.001). Failures in Spatial and Temporal components were found in both clinical groups, but only LH patients showed significantly more Content errors (p<0.01) than the control group. Also, only the LH group showed a higher number of errors for intransitive movements score (p=0.017), due to lower scores in the content component, compared to the control group (p=0.04). Transitive and intransitive CMs differ in their neurocognitive representation; transitive CM shows a bilateral distribution of its components when compared to intransitive CM, which shows a preferential left hemisphere representation. This could result from higher neurocognitive demands for movements that require use of tools, compared with more automatic communication gestures.

Assuntos

RESUMO

Este artigo aborda a discussão em torno do diagnóstico diferencial da psicose e do autismo infantis, com base em um modelo clínico fundamentalmente centrado na produção das inscrições constituintes do psiquismo a partir do laço mãe-bebê. Para tanto, realiza-se uma breve revisão dos conceitos relacionados à constituição subjetiva, aos riscos ao desenvolvimento a partir da constatação de problemas orgânicos, às funções parentais e aos princípios que norteiam a prática dessa especificidade clínica(AU)

This paper discusses the differences between the diagnosis of the infantile autism and the one of psychosis in infancy, based on a clinical model primarily focused on the production of the psyche constituent inscriptions from the mother-infant bond. This study presents a brief review of the concepts related to the subjective constitution, risks to the baby development from the finding of organic problems, parental functions and the principles that guide the practice of this clinical specificity(AU)

RESUMO

Drug target identification is of significant commercial interest to pharmaceutical companies, and there is a vast amount of research done related to the topic of therapeutic target identification. Interdisciplinary research in this area involves both the biological network community and the graph algorithms community. Key steps of a typical therapeutic target identification problem include synthesizing or inferring the complex network of interactions relevant to the disease, connecting this network to the disease-specific behavior, and predicting which components are key mediators of the behavior. All of these steps involve graph theoretical or graph algorithmic aspects. In this perspective, we provide modelling and algorithmic perspectives for therapeutic target identification and highlight a number of algorithmic advances, which have gotten relatively little attention so far, with the hope of strengthening the ties between these two research communities.

RESUMO

Cinco ratos foram expostos a um procedimento em que o elo final de uma cadeia de duas respostas era seguido por água somente se as respostas do primeiro elo fossem emitidas na presença de um estímulo sonoro. Dadas às características deste procedimento, pretendia-se que a apresentação deste estímulo tivesse a função de operação estabelecedora do valor reforçador do estímulo (uma luz) que deveria manter a primeira resposta da cadeia. Após o treino preliminar das respostas de focinhar e pressionar uma barra, cinco Fases experimentais foram introduzidas. As taxas de respostas de focinhar na presença e na ausência da suposta operação estabelecedora foram registradas durante todo o procedimento. Os resultados mostraram que, para quatro dos cinco sujeitos, as apresentações do estímulo auditivo passaram a funcionar como operações estabelecedoras e, como tais, evocaram as respostas de focinhar e estabeleceram as apresentações da luz como um reforço condicionado para estas respostas.

Five rats were exposed to a procedure in witch the final link on a chain of two responses was followed by water only if the first link responses were emitted in a presence of a sound. After preliminary training of nose poking and lever pressing responses, five experimental phases were introduced. The response rate of nose poking in the presence and absence of the supposed establishing operation was recorded during the entire procedure. The results showed that for four out of five subjects the sound presentations to functioned as a transitive conditioned establishing operations and, as such, evoked nose poking responses (evocative effect) established the onset of the light presentations as conditioned reinforces to those responses (reinforce-establishing effect).

Assuntos