Zeitschrift fur experimentelle Psychologie : Organ der Deutschen Gesellschaft fur Psychologie最新文献

This paper addresses the effects of availability and anchoring-and-adjustment on people's beliefs and values concerning environmental issues. The first three studies focus on lay people's perceptions of the causes of large scale environmental risks, the second series of three studies deals with how people value environmental goods and how much they are prepared to pay to mitigate environmental risks. In studies 1-3 we investigate the effects of availability and anchoring-and-adjustment on estimating the contribution of various factors to large scale environmental risks. Highly complex risks such as acid rain and global warming tend to be associated with multiple causes, and our results show that estimating the role of these causes is clearly affected by availability and anchoring-and-adjustment. Both have sizeable effects and persist over time. Moreover, corrective procedures only seem to have a limited effect. Availability and anchoring-and-adjustment not only play a role in judging the possible causes of risks; they also play a role in research attempting to assess the public's willingness to pay (WTP) to protect our environment. The outcomes of WTP surveys are often used as a tool to help policy decision making. In the second part of this article we present three studies on this issue. Results provide further evidence of the impact of the two heuristics on the outcomes of WTP research. Implications for research and practice are briefly discussed.

It is argued that the Stroop color-naming task is especially suited to investigate affective priming effects in the sense of an automatic spreading of activation to other concepts of the same valence, because (a) the Stroop task is not prone to an explanation of affective congruency effects on the basis of reaction priming or reaction interference, and (b) it is possible to detect specific (fast and efficient stimulus processing due to heightened accessibility) as well as nonspecific (cognitive interference, triggering of global action tendencies) effects of an activation of valenced concepts in the Stroop task. Two experiments were conducted to investigate associative and affective priming effects with the Stroop task. In a first experiment (N = 36, SOA = 300 ms) a standard priming procedure was chosen; the primes were presented without any processing instructions. In a second experiment (N = 48, SOA = 500ms) the primes had to be reproduced after naming the color of the target. In both experiments significant association effects were found for the associative material. For the valenced material no affective congruency effects were found in either experiment. The present results are not compatible with the hypothesis of an automatic affective spreading of activation that was given as an explanation of affective congruency effects in previous studies using different tasks.

Many of the changes observed in our environment today may be traced back to human action. In addition to a descriptive elaboration of possible predictor variables, the psychological analysis of environmental behavior is directed towards the identification of key variables and the structural relationships among these and behavior. Variables that are suitable to predict environmental behavior need to be identified. In this study, 215 subjects each were drawn from an urban and a rural sample; 85 further subjects were considered to be highly environmentally engaged. Thus the total sample population for this study included 515 subjects. Scales on acquisition of information, values, locus of control, attribution of responsibility, and environmental threat were administered to all subjects. A modified version of the protection-motivation theory formulated by Gardner and Stern (1996) served as a reference model. Simultaneous regression analysis revealed that scales specifically directed to the domain of environmental behavior are well suited to explain environmental actions, especially in the subset of highly engaged persons (R2 = .58). In contrast to both other groups, the acquisition of environmentally specific information was a strong predictor in this group. On the basis of these regression analyses, it is argued that additional predictors--along with the ones used in this study--must be taken into account in groups that do not display extraordinary engagement in environmental matters.

Ignoring a distractor on a prime trial generally impairs responses to that stimulus on a subsequent probe trial. This so called negative-priming (NP) effect supports the view that the representations of distracting stimuli underly a cognitive inhibition during target selection (Tipper, 1985). Aiming at the optimization of NP designs for analyzing cognitive inhibition the present paper investigates two open questions within this context: Which classical designs using words, letters, or pictures as stimuli are most accepted by subjects and at the same time result in possibly strong NP effects? What is the time course of NP, and at which interstimulus interval (ISI) the maximum is reached? In experiment 1, three "classical" NP designs were compared within one sample of subjects and a picture design was selected as the most suitable one. In experiment 2 the ISI was varied within subjects; the maximal NP effect was found at an ISI of around 1000 ms.

Empirical results of two studies on the practice of computer administration of psychodiagnostic inventories are presented. Based on the "Freiburger Persönlichkeitsinventar" (FPI-R, a German multidimensional personality inventory, Fahrenberg, Hampel & Selg, 1994) two studies (total N = 600 university students) were conducted in which (1) the standard paper-pencil questionnaire was compared with a computer administrated version, and (2) the standard item arrangement was contrasted with the presentation of the items of each subscale as a block (homogeneous item blocking), which corresponds to the extraction of subscales from more extensive inventories. The results confirm low significant effects of computer administration and of item blocking as to the means, as well as no interactions with the factor "gender." The parameters of reliability increased partially under computer administration. Computer administration itself led to a higher degree of self-consciousness. The adequacy of the FPI-R, which was standardized by paper-pencil inquest, and a computer administrated version is thus demonstrated proven.

In certain kinds of overlapping tasks subjects have to respond to two stimuli (S1 and S2), presented in close succession with variable onset asynchrony (SOA), carrying out two different responses (R1 and R2). When responding to S1 is given priority over S2 processing, reaction time (RT) to the first stimulus is unaffected by SOA. However, sometimes subjects adopt, either spontaneously or because of instruction, a different processing strategy called grouping. In this case R1 is postponed until R2 has been determined too. The present study addresses the localization of the postponed processing stage by means of the lateralized readiness potential (LRP). One group of subjects was instructed to group responses and a second group was to give priority to S1 processing. The adherence to instructions was verified by subjects' reaction times. In case of grouping the interval between LRP onset and overt reaction increased proportionally to the postponement caused by SOA. In contrast, the interval between stimulus and LRP onset was unaffected by SOA. These findings speak against assumptions that grouping causes response activation postponement; rather, the corresponding reaction is already selected and activated prior to postponement.

In recent experiments with a pseudo-random sequence of 7 consonants to recall after trial (stimulus onset asynchrony 1000 ms) a reverse relationship between P300 amplitude of the event-related potential (ERP) and letter presentation position was shown (Grune et al., 1996). It was assumed that this relationship reflects competition between encoding and retention processes in this time regime. In order to find evidence for the resource competition hypothesis in working memory a 4 x 4 grid containing 4 digits preceded a sequence of 6 consonants. In the first block subjects were instructed to ignore the grid, in two remaining blocks they were asked to remember the digits or their position in the grid and to recognize them after the letter recall. In the ignore condition the expected effect of P300 decrease with letter position was found, especially at posterior electrode sites. When subjects had to process the preceding digit grid there was no position effect of P300 caused by small P300 amplitudes in the ERPs that were elicited by the first letters of the sequence. This effect was not specific to the modality of the interfering with the letter task information from the digit grid. We conclude that the grid information occupies working memory resources that are not available for the event-related processing of consonants to recall.

The perception of the emotional content of a stimulus is a preattentive automatic process which causes an emotional reaction. As the ongoing stream of behavior might be disturbed by the emotional reaction, a controlled process is initialited at the same time, which normally leads to an inhibition of the emotional response. By means of event related potentials it should be possible to observe these controlled processes. In a first study using photographs from the International Affective Picture System, Diedrich et al. (1997) reported enhanded P300 amplitudes for emotional stimuli, even when the task distracted from the emotional content of the stimuli. This was interpreted as an index of the additional, controlled information processing elicited by the emotional content of the stimuli. Additionally, Diedrich et al. observed a frontel slow positivity, which might indicate the inhibition of the emotional response. However, this frontal slow wave might also be explained by the stimulus presentation time, which lasted 500 ms. This study is a conceptual replication of the experiment of Diedrich et al. Stimulus presentation time of neutral and emotional slides was varied in three steps (250 ms, 500 ms and 2000 ms). Subjects either performed a structural or an emotion-focused task on the stimuli. The results for the P300 component were exactly replicated. However, the variation of slow frontal positivity differed from that in the first study. Differences in the intensity of the emotional stimuli are discussed as a reason für this result.

This study examined memory encoding of auditorily presented abstract and concrete nouns. 22 subjects performed various blocks of a free recall memory task in which lists of 22 either abstract or concrete words had to be memorized. Consistent with a large variety of memory studies, recall performance was better for concrete than for abstract words. When the event-related potentials (ERPs) recorded during study were selectively averaged for those words that were subsequently recalled and those subsequently not recalled, the ERPs were more positive going for words that were subsequently recalled. These Dm effects (Difference due to memory) started around 500 ms post-stimulus and differed in timing and scalp topography for both types of words: For abstract words, they were present in an early (i.e., 600 to 1100 ms) time interval at parieto-occipital electrodes only. In contrast, for concrete words, Dm effects were obtained with a broad topographic distribution in the 600 to 1000 ms time range and were also present in a late time interval (1100 to 1600 ms) at fronto-central recording sites. The topographical dissociations of the Dm effects in the early time interval are taken to reflect the larger distinctiveness of concrete words during encoding, whereas the late effects presumably play a functional role in elaborative processing of concrete words. The results do not agree with models of word concreteness that propose separate processing systems for the two types of words, and rather support those models that propose quantitative differences in the processing of abstract and concrete words.