Mergers and group status: the impact of high,low and equal group status on identification and satisfaction with a company merger,experienced controllability,group identity and group cohesion

Although mergers are seen as tools to enhance business in today's global marketplace, they have had a low success rate, possibly because the focus has been on financial and legal issues rather than on the human factors involved. In this respect, focusing on the social psychological variables, social identity theory can provide an explanation for the failure of most mergers. An experiment based on this theory involving mergers between two workgroups was conducted to investigate the effects of merger‐related status on participants' psychological responses to the mergers. Thirty‐six small groups were assigned to three different status groups (high, low and equal status groups) using the minimal group paradigm. Most negative responses to the merger—in terms of identification with the merger group, satisfaction with the merger, common in‐group identity, group cohesion and controllability—were given by the members of the low status groups. Contrary to expectations, status was not related to the performance of the groups. Theoretical and practical implications are discussed. Copyright © 2007 John Wiley & Sons, Ltd.     

Hormonal and monoamine signaling during reinforcement of hippocampal long-term potentiation and memory retrieval

Recently it was shown that holeboard training can reinforce, i.e., transform early-LTP into late-LTP in the dentate gyrus during the initial formation of a long-term spatial reference memory in rats. The consolidation of LTP as well as of the reference memory was dependent on protein synthesis. We have now investigated the transmitter systems involved in this reinforcement and found that LTP-consolidation and memory retrieval were dependent on β-adrenergic, dopaminergic, and mineralocorticoid receptor (MR) activation, whereas glucocorticoid receptors (GRs) were not involved. Blockade of the β-adrenergic signaling pathway significantly increased the number of reference memory errors compared with MR and dopamine receptor inhibition. In addition, β-adrenergic blockade impaired the working memory. Therefore, we suggest that β-adrenergic receptor activation is the main signaling system required for the retrieval of spatial memory. In addition, other modulatory interactions such as dopaminergic as well as MR systems are involved. This result points to specific roles of different modulatory systems during the retrieval of specific components of spatial memory. The data provide evidence for similar integrative interactions between different signaling systems during cellular memory processes.     

The role of first- and second-order stimulus features for human overt attention

When processing complex visual input, human observers sequentially allocate their attention to different subsets of the stimulus. What are the mechanisms and strategies that guide this selection process? We investigated the influence of various stimulus features on human overt attention--that is, attention related to shifts of gaze with natural color images and modified versions thereof. Our experimental modifications, systematic changes of hue across the entire image, influenced only the global appearance of the stimuli, leaving the local features under investigation unaffected. We demonstrated that these modifications consistently reduce the subjective interpretation of a stimulus as "natural" across observers. By analyzing fixations, we found that first-order features, such as luminance contrast, saturation, and color contrast along either of the cardinal axes, correlated to overt attention in the modified images. In contrast, no such correlation was found in unmodified outdoor images. Second-order luminance contrast ("texture contrast") correlated to overt attention in all conditions. However, although none of the second-order color contrasts were correlated to overt attention in unmodified images, one of the second-order color contrasts did exhibit a significant correlation in the modified images. These findings imply, on the one hand, that higher-order bottom-up effects--namely, those of second-order luminance contrast--may partially account for human overt attention. On the other hand, these results also demonstrate that global image properties, which correlate to the subjective impression of a scene being "natural," affect the guidance of human overt attention.     

Activation of midbrain structures by associative novelty and the formation of explicit memory in humans

Recent evidence suggests a close functional relationship between memory formation in the hippocampus and dopaminergic neuromodulation originating in the ventral tegmental area and medial substantia nigra of the midbrain. Here we report midbrain activation in two functional MRI studies of visual memory in healthy young adults. In the first study, participants distinguished between familiar and novel configurations of pairs of items which had been studied together by either learning the location or the identity of the items. In the second study, participants studied words by either rating the words' pleasantness or counting syllables. The ventral tegmental area and medial substantia nigra showed increased activation by associative novelty (first study) and subsequent free recall performance (second study). In both studies, this activation accompanied hippocampal activation, but was unaffected by the study task. Thus midbrain regions seem to participate selectively in hippocampus-dependent processes of associative novelty and explicit memory formation, but appear to be unaffected by other task-relevant aspects.     

Late-associativity, synaptic tagging, and the role of dopamine during LTP and LTD

Protein synthesis-dependent, synapse input-specific late phases of long-term potentiation (LTP) and depression (LTD) may underlie memory formation at the cellular level. Recently, it was described that the induction of LTP can mark a specifically activated synapse by a synaptic tag to capture synapse non-specific plasticity-related proteins (PRPs) and thus maintaining input-specific LTP for prolonged periods. Here we show in rat hippocampal slices in vitro, that the induction of protein synthesis-dependent late-LTD is also characterized by synaptic tagging and that heterosynaptic induction of either LTD or LTP on two sets of independent synaptic inputs S1 and S2 can lead to late-associative interactions: early-LTD in S2 was transformed into a late-LTD, if late-LTP was induced in S1. The synthesis of process-independent PRPs by late-LTP in S1 was sufficient to transform early- into late-LTD in S2 when process-specific synaptic tags were set. We name this new associative property of cellular information processing 'cross-tagging.'     

Group decision making in hidden profile situations: dissent as a facilitator for decision quality

The effect of diversity in individual prediscussion preferences on group decision quality was examined in an experiment in which 135 three-person groups worked on a personnel selection case with 4 alternatives. The information distribution among group members constituted a hidden profile (i.e., the correct solution was not identifiable on the basis of the members' individual information and could be detected only by pooling and integrating the members' unique information). Whereas groups with homogeneous suboptimal prediscussion preferences (no dissent) hardly ever solved the hidden profile, solution rates were significantly higher in groups with prediscussion dissent, even if none of these individual prediscussion preferences were correct. If dissent came from a proponent of the correct solution, solution rates were even higher than in dissent groups without such a proponent. The magnitude of dissent (i.e., minority dissent or full diversity of individual preferences) did not affect decision quality. The beneficial effect of dissent on group decision quality was mediated primarily by greater discussion intensity and to some extent also by less discussion bias in dissent groups.     

Connecting terror management and dissonance theory: Evidence that mortality salience increases the preference for supporting information after decisions

From the perspective of terror management theory, reminders of mortality should intensify the desire to pursue cognitive consistency. The authors investigated this notion with regard to dissonance theory starting from the finding of research on "selective exposure to information" that after having made a decision, people prefer consonant over dissonant information. The authors found that following mortality salience, people indeed showed an increased preference for information that supported their decision compared to information conflicting with it. However, this only occurred with regard to a worldview-relevant decision case. For a fictitious decision scenario, mortality salience did not affect information seeking. Practical and theoretical implications are discussed.     

Information sampling and group decision making: the effects of an advocacy decision procedure and task experience

Group discussions tend to focus on information that was previously known by all members (shared information) rather than information known by only 1 member (unshared information). If the shared information implies a suboptimal alternative, this sampling bias is associated with inaccurate group decisions. The present study examines the impact of 2 factors on information exchange and decision quality: (a) an advocacy group decision procedure versus unstructured discussion and (b) task experience. Results show that advocacy groups discussed both more shared and unshared information than free-discussion groups. Further, with increasing experience, more unshared information was mentioned in advocacy groups. In contrast, there was no such increase in unstructured discussions. Yet advocacy groups did not significantly improve their decision quality with experience.     

Subjective Well-Being and Policy

This paper analyses whether the aggregation of individual happiness scores to a National Happiness Index can still be trusted once governments have proclaimed their main objective to be the pursuit—or even maximization—of this National Happiness Index. The answer to this investigation is clear-cut: as soon as the National Happiness Index has become a policy goal, it can no longer be trusted to reflect people’s true happiness. Rather, the Index will be systematically distorted due to the incentive for citizens to answer strategically and the incentive for government to manipulate the Index in its favour. Such a distortion would arise even if the measurement of subjective well-being correctly reflected actual happiness before the intervention of government. Governments in a democracy should establish the conditions enabling individuals to become happy. The valuable and important results of happiness research should be introduced into the political process. Each person should be free to pursue happiness according to his or her preferences. This process is supported by obedience to the rule of law, human rights and free media, as well as by extended political participation rights, decentralized public decision-making, an open and effective education system fostering upward mobility and the possibility to find suitable employment.