"Economic man" in cross-cultural perspective: behavioral experiments in 15 small-scale societies

Researchers from across the social sciences have found consistent deviations from the predictions of the canonical model of self-interest in hundreds of experiments from around the world. This research, however, cannot determine whether the uniformity results from universal patterns of human behavior or from the limited cultural variation available among the university students used in virtually all prior experimental work. To address this, we undertook a cross-cultural study of behavior in ultimatum, public goods, and dictator games in a range of small-scale societies exhibiting a wide variety of economic and cultural conditions. We found, first, that the canonical model - based on self-interest - fails in all of the societies studied. Second, our data reveal substantially more behavioral variability across social groups than has been found in previous research. Third, group-level differences in economic organization and the structure of social interactions explain a substantial portion of the behavioral variation across societies: the higher the degree of market integration and the higher the payoffs to cooperation in everyday life, the greater the level of prosociality expressed in experimental games. Fourth, the available individual-level economic and demographic variables do not consistently explain game behavior, either within or across groups. Fifth, in many cases experimental play appears to reflect the common interactional patterns of everyday life.     

Processes of task-set reconfiguration: switching operations and implementation operations

When participants are asked to shift between four dimensionally organized tasks which differ in the type of judgment (numerical vs. spatial) and/or the judgment-to-response mapping (compatible vs. incompatible), a characteristic profile of shift costs can be observed. It can be accounted for in terms of two different types of operations: generalizing switching operations on a dimensionally organized set of task representations and implementation operations [T. Kleinsorge, H. Heuer, Psycholog. Res. 62 (1999) 300]. In a first experiment we corroborated our previous findings by way of a new procedure that makes it possible to estimate shift costs unconfounded by a number of factors that are likely to affect estimates of shift costs based on more conventional procedures. In a second experiment we investigated the endogenous and exogenous nature of the postulated types of operations. The characteristic profile of shift costs disappeared when long precue intervals (PCIs) were used. Augmented by a formal analysis, this finding suggests that both switching and implementation operations are endogenously controlled. In addition, there remained some residual shift costs which were essentially insensitive to the nature of the task shift but depended on the difficulty of the new task. Most likely they reflect a process of consolidation of an already configured task set.     

Stimulation seeking and hyperactive behavior in children with ADHD: a re-analysis

To examine the stimulation-seeking function of hyperactivity in children with ADHD, Antrop and colleagues analyzed the behavior of 30 hyperactive and 30 nonhyperactive children during a waiting situation, either with or without extra stimulation. The behavior was assessed by frequency measures. In their study it was hypothesized that children with ADHD would show a greater decrease in activity in the presence of stimulation than control children. Since confirmation for this hypothesis was only found for 2 of 25 target behaviors, the present re-analysis included other behavioral measures to assess two relationships: first, how hyperactivity varies under fixed time conditions, using measures of duration and intensity of behavior instead of frequency measures, and second, how the perceived duration of waiting time affects behavior. Analysis indicated that children with ADHD showed a greater decrease in behavior in the presence of stimulation for touching objects and movements of trunk, as reported. Further, children who underestimated the waiting period were more apt to seek additional stimulation in its absence than those who overestimated the waiting period.     

Determinants of diagnostic prototypicality judgments of the personality disorders

We evaluated the impact of three factors that have been suggested to be important determinants of the diagnostic process pertaining to personality disorders: (a) the number of features representative of a personality disorder category; (b) the extent to which those features are typical of the category, and (c) the dominance or proportion of category features to the total number of features. Thirty-two clinical psychologists evaluated 12 profiles of hypothetical patients in which these factors were varied factorially. The results revealed strong effects of typicality and dominance, but no effects for number. Implications for the assessment and classification of personality disorders are discussed.     

A room with a view and a polarizing cue: individual differences in the stimulus control of place navigation and passive latent learning in the water maze

We investigated individual differences in the stimulus control of navigational behavior in the water maze by comparing measures of place learning in one environment to measures of latent learning (via passive placement on the goal platform) in a novel environment. In the first experiment, 12 rats were trained to find a slightly submerged hidden platform at a fixed location in room A for 10 days (4 trials/day). Fast and slow place learners were identified by their mean escape latency and cumulative distance to the goal during acquisition. The same animals were then given a 2-min passive placement on the submerged platform in room B. Latent learning was assessed by the animal's escape latency on a single swim trial immediately following the placement in room B. The results showed that the good latent learners in room B were not necessarily the fast place learners in room A. This weak correlation may be related to the fact that some rats swam near the area in room B that corresponded to the former goal location in room A relative to a common polarizing cue (i.e., the door/entrance to both rooms). When the view of the door was blocked in a second experiment a significant positive correlation between place acquisition and the latent learning test was obtained, although escape performance following passive placement was not improved. These findings suggest that while place navigation and latent learning via passive placement may involve some common cognitive-spatial function, other associative (S-S and/or S-R) processes that occur during place navigation/active movement may be required for animals to exhibit truly accurate navigational behavior characteristic of asymptotic escape performance in the water maze. Additional implications for neurobiological studies using a procedural pretraining design are discussed.     

Adaptation to a direction-dependent visuomotor gain in the young and elderly

Consistent with the widely accepted notion of separate specification of movement amplitude and direction, it has been argued that there is also a categorical difference between adaptation to novel visuomotor rotations and to novel visuomotor gains. In line with this view, ageing seems to affect rotation and gain adaptation differently in that age-related impairments are consistently found for the former, but not for the latter. In this study we ask whether the contrasting findings could also be ascribed to differences in the level of difficulty of gain and rotation adaptation tasks, respectively. In order to increase the difficulty of gain adaptation, younger and older participants had to adapt to a direction-dependent gain transformation. Results revealed direction-dependent adaptation in both groups. More importantly, we replicated the typical findings of age-related impairments of adaptation, but not of aftereffects, that were previously only reported for rotation adaptation. Younger participants also showed superior explicit knowledge regarding the novel visuomotor mapping as compared to the older participants. We show that this knowledge was used by younger participants to selectively augment adaptive shifts. Finally, our findings suggest that the difficulty of the novel visuomotor transformation and, related to this, the involvement of explicit knowledge in adaptation is critical for age-related changes to show up, but not the type of adaptation task, rotation and gain adaptation, respectively.     

Native language effects in learning second-language grammatical gender: A training study

We investigated cross-language influences in the representation and acquisition of Dutch word gender by native speakers of German. Participants named pictures in Dutch, using gender-marked noun phrases, and were trained on this task using feedback. Nouns differed in gender compatibility and cognate status with respect to German. The results show clear effects of cross-language gender compatibility and cognate status on response accuracy, certainty, and consistency. Feedback during training reduced gender errors approximately by half, and affected the different item conditions similarly. Furthermore, relative to the initial error rates, incorrect gender responses given with great certainty were not harder to modify than those with lower certainty. The results provide insights into the nature and stability of correct and incorrect gender representations in L2, and demonstrate the pervasiveness of transfer from the first to the second language even after intensive training.     

Is it the symptom or the relation to it? Investigating potential mediators of change in acceptance and commitment therapy for psychosis

Cognitive and behavioral interventions have been shown to be efficacious when used as an adjunct to pharmacotherapy for psychotic disorders. However, little previous research has investigated potential mediators of change in psychological treatments for psychosis. Acceptance and mindfulness-based therapies do not focus on directly reducing the psychotic symptoms themselves, but instead attempt to alter the patient's relationship to symptoms to decrease their negative impact. The current study examined this issue with data from a previously published randomized trial comparing brief treatment with Acceptance and Commitment Therapy (ACT) versus treatment as usual for hospitalized patients with psychotic symptoms (Gaudiano & Herbert, 2006a). Results showed that the believability of hallucinations at posttreatment statistically mediated the effect of treatment condition on hallucination-related distress. Hallucination frequency did not mediate outcome. The current study is a first step toward understanding the potential mechanisms of action in psychological treatments for psychosis.     

Intrinsic,identified, and controlled types of motivation for school subjects in young elementary school children

Background. There are two approaches to the differential examination of school motivation. The first is to examine motivation towards specific school subjects (between school subject differentiation). The second is to examine school motivation as a multidimensional concept that varies in terms of not only intensity but also quality (within school subject differentiation). These two differential approaches have led to important discoveries and provided a better understanding of student motivational dynamics. However, little research has combined these two approaches. Aims. This study examines young elementary students' motivations across school subjects (writing, reading, and maths) from the stance of self‐determination theory. First, we tested whether children self‐report different levels of intrinsic, identified, and controlled motivation towards specific school subjects. Second, we verified whether children self‐report differentiated types of motivation across school subjects. Sample. Participants were 425 French‐Canadian children (225 girls, 200 boys) from three elementary schools. Children were in Grades 1 (N=121), 2 (N=126), and 3 (N=178). Results. Results show that, for a given school subject, young elementary students self‐report different levels of intrinsic, identified, and controlled motivation. Results also indicate that children self‐report different levels of motivation types across school subjects. Our findings also show that most differentiation effects increase across grades. Some gender effects were also observed. Conclusion. These results highlight the importance of distinguishing among types of school motivation towards specific school subjects in the early elementary years.