Differential use of distance and location information for spatial localization

Five experiments are reported in which subjects judged the movement or spatial location of a visible object that underwent a combination of real and induced (illusory) motion. When subjects attempted to reproduce the distance that the object moved by moving their unseen hands, they were more affected by the illusion than when they pointed to the object's perceived final location. Furthermore, pointing to the final location was more affected by the illusion when the hand movement began from the same position as that at which the object initially appeared, as compared with responses that began from other positions. The results suggest that people may separately encode two distinct types of spatial information: (1) information about the distance moved by an object and (2) information about the absolute spatial location of the object. Information about distance is more susceptible to the influence of an induced motion illusion, and people appear to rely differentially on the different types of spatial information, depending on features of the pointing response. The results have important implications for the mechanisms that underlie spatially oriented behavior in general.     

Gender differences in emotional support and depressive symptoms among adolescents: A prospective analysis

Investigated components of perceived emotional support, including support from family members, nonfamily adults, and peers, as predictors of depressive symptoms in a sample of 333 high school students (age 14-18) using a prospective design. Analyses of panel questionnaire data at two points in time suggest there are significant gender differences both in the quality of perceived support reported by adolescents and in the importance of support variables as predictors of depressive symptoms. Although there are no gender differences in the magnitude of perceived support from family members, girls report higher emotional support from both nonfamily adults and peers than boys report. Simple correlations between family support and depression are significantly stronger for girls than for boys. Results of hierarchical regression analyses, controlling for initial level of symptoms, reveal that whereas both nonfamily adult and friend components of perceived support are significant predictors of changes in symptoms for girls, none of these variables significantly predicts changes in symptoms for boys in this sample. In addition, initial symptoms predict changes in family support for girls but not for boys.     

Aggravation of DSS-induced colitis after chronic subordinate colony (CSC) housing is partially mediated by adrenal mechanisms

Chronic subordinate colony housing (CSC) is a relevant chronic psycho-social stressor for male mice. Here, we investigated effects of CSC on the severity of dextran sulphate sodium (DSS)-induced colitis and the involvement of adrenal mechanisms. After 19 days of CSC, male C57BL/6 mice were treated with 1% DSS (8 days). After 8 days, inflammatory shortening of the colon and the histological inflammation score were increased in CSC mice. Additionally, the increased secretion of pro-inflammatory cytokines by mesenteric lymph node cells found on day 2 and 4 of DSS treatment was down-regulated in CSC mice on day 8 of DSS treatment, paralleled by an increase in plasma corticosterone. In contrast, in unstressed controls, elevation of cytokine secretion was delayed and only found on day 8 of DSS treatment, associated with a prompt rise in plasma corticosterone. To reveal adrenal mechanisms in CSC-induced effects on colitis, mice were adrenalectomized, exposed to CSC and treated with DSS (8 days). In adrenalectomized CSC mice, the severity of DSS-induced colitis was reduced, as body weight loss, shortening of colon, histological damage score, and cytokine secretion from mesenteric lymph node cells were diminished compared with sham-operated CSC mice. In conclusion, exposure to chronic psycho-social stress increases the severity of acute DSS colitis, an effect which is, at least partly, mediated by adrenal mechanisms.     

Double dissociation between implicit and explicit personality self-concept: the case of shy behavior

Using the trait of shyness as an example, the authors showed that (a) it is possible to reliably assess individual differences in the implicitly measured self-concept of personality that (b) are not accessible through traditional explicit self-ratings and (c) increase significantly the prediction of spontaneous behavior in realistic social situations. A total of 139 participants were observed in a shyness-inducing laboratory situation, and they completed an Implicit Association Test (IAT) and explicit self-ratings of shyness. The IAT correlated moderately with the explicit self-ratings and uniquely predicted spontaneous (but not controlled) shy behavior, whereas the explicit ratings uniquely predicted controlled (but not spontaneous) shy behavior (double dissociation). The distinction between spontaneous and controlled behavior was validated in a 2nd study.     

A comparison of general and illness-related locus of control in Russians, ethnic German migrants and Germans

General and illness-related locus of control play an immensely important role in the adherence and cooperation of patients in their therapy. Until now, culture-specific aspects of these subjective theories have rarely been investigated. However, in view of the growing proportion of migrants in the German population, they are becoming increasingly significant. In a project supported by the Volkswagenstiftung (Volkswagen Foundation), a total of 607 healthy people were surveyed. The sample includes 307 ethnic German migrants from the successor states of the former Soviet Union (descendents of German origin who had emigrated to Russia during the 18th and 19th centuries) and 300 native Russians in Russia. They were compared with 100 Germans (matched from a previous study). The data were collected using questionnaires entitled "Multidimensional Health Locus of Control (MHLC)" and "Illness-related Locus of Control". The ethnic German migrants differed from the Russian sample in their health beliefs and attitudes towards medicine. However, in the first 18 months after migration, hardly any changes were observed. Fatalistic factors played only a minor role. Locus of health control was associated with beliefs about recovery from myocardial infarcts and tumours. Socio-demographic variables were of varying significance in the individual cultures. Gender influences on health beliefs were different in the subsamples. The level of education had only a minor influence on health attitudes. For those individuals who were acquainted with an ill person, internal factors in treatment of myocardial infarct and external psychosocial factors in cure of cancer played a larger role.     

Lateral information transfer across saccadic eye movements

Our perception of the visual world remains stable and continuous despite the disruptions caused by retinal image displacements during saccadic eye movements. The problem of visual stability is closely related to the question of whether information is transferred across such eye movements-and if so, what sort of information is transferred. We report experiments carried out to investigate how presaccadic signals at the location of the saccade goal influence the visibility of postsaccadic test signals presented at the fovea. The signals were Landolt rings of differ-ent orientations. If the orientations of pre- and postsaccadic Landolt rings were different, the thresholds of the test signals were elevated by about 20%–25% relative to those at the static control condition. When the orientations were identical, no such elevation occurred. This selective threshold elevation effect proved to be a phenomenon different from ordinary saccadic suppression, although it was closely related to the execution of the saccadic eye movement. The consequences for visual stability are discussed.     

Dorsal and ventral processing under dual-task conditions

It is widely acknowledged that visual input is processed along two anatomically and functionally distinct pathways--a ventral pathway for conscious perception and a dorsal pathway for action control. The present study investigated whether the apparent direct and unmediated processing in the dorsal stream is subject to capacity limitations. Specifically, we tested whether a simple dorsal task of grasping an object is affected by the psychological refractory period (PRP), a well-known indication of capacity limitations. Subjects performed an auditory choice reaction task and then, following varying delays, had to judge an object's width (ventral task) or grasp an object across its width (dorsal task). Although these tasks were differentially affected by irrelevant variation of the objects' length, they were subject to comparable dual-task interference. These results show that despite important differences between ventral and dorsal information processing, both modes of processing are constrained by limited capacities.     

Iconic memory and central processing capacity

Three experiments were conducted to assess whether or not iconic memory is influenced by demands placed upon central processing capacity. In Experiment 1 S was required to store material in short-term memory while performing an iconic memory task. In Experiments 2 and 3 S performed an auditory classification task concurrently with iconic storage. The three experiments did not reveal any significant impairment of iconic memory as a function of performing a subsidiary task. Similarly, performance on the subsidiary tasks did not suffer as a result of the concurrent iconic memory task.     

The dependency of the validity of information integration on cognitive variables and the judgement task

Simple models of information integration focus essentially on the combination of the components of information. This research investigated whether cognitive variables in the constructs of intelligence and cognitive complexity, as well as concentration, could predict the conditions of simple models of judgement. As additional predictors, the two qualitative variables [type of information] and [experience of the judgement task] were introduced. Subjects judged three types of stimuli using the pair comparison method. The conditions of the judgement models were analysed in the framework of the conjoint-measurement approach. Five different regression functions provided mediocre approximations to the 10 conditions of the models, when the 9 cognitive variables were considered. The small differences did not favour one of the five functions. The introduction of the qualitative predictor [type of information] improved the estimations more clearly than the experience of the judgement task, the effect of which was small.