New knowledge derived from learned knowledge: functional-anatomic correlates of stimulus equivalence

Forming new knowledge based on knowledge established through prior learning is a central feature of higher cognition that is captured in research on stimulus equivalence (SE). Numerous SE investigations show that reinforcing behavior under control of distinct sets of arbitrary conditional relations gives rise to stimulus control by new, derived relations. This investigation examined whether frontal-subcortical and frontal-parietal networks known to support reinforced conditional relations also support derived conditional relations. Twelve adult subjects completed matching-to-sample (MTS) training with correct/wrong feedback to establish four trained conditional relations within two distinct, three-member stimulus classes: (1) A1-->B1, B1-->C1 and (2) A2-->B2, B2-->C2. Afterwards, functional neuroimaging was performed when MTS trials were presented involving matching two identical circles (a sensorimotor control condition), trained relations (A-->B, B-->C), and derived relations: symmetry (B-->A, C-->B), transitivity (A-->C), and equivalence (C-->A). Conditional responding to trained and derived relations was similarly correlated with bilateral activation in the targeted networks. Comparing trained to derived relations, however, highlighted greater activation in several prefrontal regions, the caudate, thalamus, and putamen, which may represent the effects of extended training or feedback present during imaging. Each derived relation also evidenced a unique activation pattern. Collectively, the findings extend the role of frontal-subcortical and frontal-parietal networks to derived conditional relations and suggest that regional involvement varies with the type of derived conditional relation.     

Multicriteria agency theory

This paper extends standard agency theoretic models to explicitly take into account the presence of multiple criteria at the agent level. Two approaches for this extension are discussed. In the first approach we consider only the minimum information that the principal might posses about the agent’s preferences for different criteria. It can be shown that in this context the principal has limited possibilities to influence the agent’s behaviour. In the second approach a richer information set is considered. In this context it is possible to determine probabilities of alternatives being selected by the agent. We also analyse how these probabilities can be influenced by the principal and how this affects the principal’s net profit. © 1998 John Wiley & Sons, Ltd.     

Complexity,information and time

Evolution proceeds in time. Time is experienced as change only, predominantly irreversible change. Measuring change in the form of information growth it is possible to define a measure for the amount of time produced during information increase. Systems creating information contribute to the generation of time. To be able to create information, a system has to be highly complex. The more complex a system is, the more it can contribute to generation of time. The rate of time generation is determined by the capability of the system to gain information. Complexity, information accumulation, and time generation are therefore synonyms.     

Opfer-überzeugungen

The public interest in ??new?? clinical symptoms is described exemplified by burnout, mobbing and trauma. In the background self-explanations by patients as well as interests of therapists can be recognized. Both can be understood as an expression of subconsciously reflected contemporary convictions. Post-traumatic stress syndrome and the sequelae of abuse, which are probably diagnosed too often in guideline correct psychotherapy, throw up questions on the appropriate therapy and possible injurious side effects. The social background to the psychotherapeutic fascination with trauma will be discussed.