A preferential matching problem

A matching method proposed by Dr. C. E. Stuart is presented in some detail and the essentials for a test of significance are derived. This method differs from the older matching methods in that partial credit is allowed for a near miss. A slight variation of the method permits the matching of one item withM sets ofn traits.     

Simultaneous visual discrimination in Asian elephants

Two experiments explored the behavior of 20 Asian elephants (Elephas aximus) in simultaneous visual discrimination tasks. In Experiment 1, 7 Burmese logging elephants acquired a white+/black- discrimination, reaching criterion in a mean of 2.6 sessions and 117 discrete trials, whereas 4 elephants acquired a black+/white- discrimination in 5.3 sessions and 293 trials. One elephant failed to reach criterion in the white+/black- task in 9 sessions and 549 trials, and 2 elephants failed to reach criterion in the black+/white- task in 9 sessions and 452 trials. In Experiment 2, 3 elephants learned a large/small transposition problem, reaching criterion within a mean of 1.7 sessions and 58 trials. Four elephants failed to reach criterion in 4.8 sessions and 193 trials. Data from both the black/white and large/small discriminations showed a surprising age effect, suggesting that elephants beyond the age of 20 to 30 years either may be unable to acquire these visual discriminations or may require an inordinate number of trials to do so. Overall, our results cannot be readily reconciled with the widespread view that elephants possess exceptional intelligence.     

Attentional inhibition has social-emotional consequences for unfamiliar faces

Visual attention studies often rely on response time measures to show the impact of attentional facilitation and inhibition. Here we extend the investigation of the effects of attention on behavior and show that prior attentional states associated with unfamiliar faces can influence subsequent social-emotional judgments about those faces. Participants were shown pairs of face images and were asked to withhold a response if a transparent stop-signal cue appeared over one of the faces. This served to associate the cued face with an inhibitory state. Later, when asked to make social-emotional choices about these face pairs, participants chose uncued faces more often than cued faces as "more trustworthy" and chose cued faces more often than uncued faces as "less trustworthy." For perceptual choices, there was no effect of how the question was framed (which face is "on a lighter background" vs. "on a darker background"). These results suggest that attentional inhibition can be associated with socially relevant stimuli, such as faces, and can have specific, deleterious effects on social-emotional judgments.     

Socially meaningful vocal plasticity in adult Campbell's monkeys (Cercopithecus campbelli)

Campbell's monkeys (Cercopithecus campbelli) frequently exchange vocalizations, the combined-harmonic calls, with individuals responding to one another's calls. Previous work has shown that these calls can be grouped into several structural variants. Adult females differ in their variant repertoires, which may change during their adult life, particularly after changes in the group composition. Playback of females' currently produced variants triggered vocal responses from other group members, whereas the same females' former, no longer used variants and those of stranger females never did. In contrast, former variants caused long-term cessation of vocal behavior, whereas stranger variants had no effect. Data showed that monkeys were able to distinguish between the different types of variants, indicating that these calls form part of a long-term social memory.     

Psychoanalytische Therapie

A statement of the professional umbrella society DGPT is presented that was formulated in cooperation with the various professional societies and with the German Society of Psychosomatic Medicine and Psychotherapy and the Society of Child and Adolescent Therapy. The statement is a reaction to the public claim for effective evidence of psychotherapy and takes the opportunity for a comprehensive presentation of this field. In the introduction Alf Gerlach, as chairman of the umbrella society at the time of the formulation of this statement and now executive chairman responsible for coordinating research, describes the history of the development of the statement.There were two particular moments prompting this statement. On the one hand the Scientific Advisory Board for Psychotherapy as an advisory committee based on the law of psychotherapy, has presented demands for effective evidence that are incompatible with psychoanalysis. Thus, the recognition of psychoanalysis as a treatment method for illnesses was put in doubt. On the other hand, a suggestion was put forward to the Board to recognize psychodynamic psychotherapy as an independent entity. This questioned the unity of the psychotherapeutic field.The statement was passed onto the Scientific Advisory Board last autumn. It is intended for a professional audience and includes answers to important issues of this field. It will have an important role to play in future discussions about professional politics. For this reason, we have decided to begin the present issue of our journal with this statement and thus to open a wide discussion forum.

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Deutsche Gesellschaft für Psychoanalyse, Psychotherapie, Psychosomatik und Tiefenpsychologie e.V. (DGPT)In Verbindung mit:Deutsche Gesellschaft für Analytische Psychologie (DGAP)Deutsche Gesellschaft für Individualpsychologie (DGIP)Deutsche Gesellschaft für Psychotherapeutische Medizin (DGPM)Deutsche Psychoanalytische Gesellschaft (DPG)Deutsche Psychoanalytische Vereinigung (DPV)Vereinigung Analytischer Kinder- und Jugendlichen-Psychotherapeuten (VAKJP)Redaktion: Stephan Hau und Marianne Leuzinger-Bohleber

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Predicting risk sensitivity in humans and lower animals: risk as variance or coefficient of variation

This article examines the statistical determinants of risk preference. In a meta-analysis of animal risk preference (foraging birds and insects), the coefficient of variation (CV), a measure of risk per unit of return, predicts choices far better than outcome variance, the risk measure of normative models. In a meta-analysis of human risk preference, the superiority of the CV over variance in predicting risk taking is not as strong. Two experiments show that people's risk sensitivity becomes strongly proportional to the CV when they learn about choice alternatives like other animals, by experiential sampling over time. Experience-based choices differ from choices when outcomes and probabilities are numerically described. Zipf's law as an ecological regularity and Weber's law as a psychological regularity may give rise to the CV as a measure of risk.     

Simultaneous cognitive operations in working memory after dual-task practice

The authors tested the hypothesis that with adequate practice, people can execute 2 cognitive operations in working memory simultaneously. In Experiment 1, 6 students practiced updating 2 items in working memory through 2 sequences of operations (1 numerical, 1 spatial). In different blocks, imperative stimuli for the 2 sequences of operations were presented either simultaneously or sequentially. Initially, most participants experienced substantial dual-task costs. After 24 sessions of practice, operation latencies for simultaneous presentation were equal to the maximum of times for the 2 operations in the sequential condition, suggesting perfect timesharing. Experiment 2 showed that a reduction of dual-task costs requires practice on the combination of the 2 updating tasks, not just practice on each individual task. Hence, the reduction of dual-task costs cannot be explained by shortening or automatization of individual operations.