Refine
Year of publication
- 2011 (31) (remove)
Document Type
- Doctoral Thesis (13)
- Article (11)
- Book (5)
- Preprint (1)
- Review (1)
Has Fulltext
- yes (31) (remove)
Is part of the Bibliography
- no (31)
Keywords
- fMRI (2)
- Anstrengung (1)
- Belohnung (1)
- Computer (1)
- Depression (1)
- Diversity Beliefs (1)
- Diversity Climates (1)
- Diversity Management (1)
- Diversität (1)
- Diversitätsüberzeugungen (1)
Institute
- Psychologie (31) (remove)
The current work investigated the association of trait anxiety and the neural efficiency of cognitive processing for affectively neutral (not threat-related) information. In a sample of 46 healthy volunteers, three fMRI experiments were conducted to test the prediction derived from attentional control theory (Eysenck et al., 2007) that high as compared to low trait-anxious individuals expend more neural effort on tasks requiring the top-down control of attention to reach a given level of performance. In a colour-word Stroop task requiring the inhibition of irrelevant stimulus information and associated responses as well as in a working-memorymanipulation task requiring the shifting of attention between items in working memory, trait anxiety (as measured with the State-Trait Anxiety Inventory; Spielberger et al., 1970) was positively associated with task-related increases in the activation of two adjacent regions in the right dorsolateral prefrontal cortex (DLPFC). The finding that along with a stronger activation of this brain region commonly implicated in top-down control processes, the high-anxious subjects showed equal (working memory manipulation) or worse (Stroop) performance when compared to low-anxious subjects, does support the assumption that processing is less efficient in the high anxious. However, in contrast to the predictions, trait anxiety did not show a significant association with task-related brain activation in a task-switching paradigm requiring shifting between task sets. It is discussed how different attentional control demands of the task may account for differences in the effects of trait anxiety on overt behavioural performance and underlying neural processes. In addition to DLPFC activation, trait anxiety modulated the functional connectivity of distributed regions involved in processing of the Stroop and the working-memory-manipulation task. It is discussed how the observed differences in regional DLPFC activation and network connectivity relate to each other. A possible interpretation suggests that activation increases in the DLPFC reflect an attempt to compensate for suboptimal connectivity by investing more effort in prefrontally supported control processes. Overall, the current work shows an association of trait anxiety with the neural efficiency of cognitive processing in affectively neutral tasks involving attentional control. Furthermore, it suggests that investigations of neural efficiency should take into account difference in functional integration in addition to regional activation.
The construct diversity describes the collective amount of differences among members within a social unit. The present dissertation is based on the assumption that, through engagement with diversity, people acquire an understanding of what role diversity plays in the societies, organizations, work groups, or other social units they are part of. This understanding of the role diversity plays in a given social unit provides a vantage point from which people will engage with diversity in the future. These vantage points from which people engage with diversity are the general subject matter of the present dissertation. Two main research questions are addressed in this regard: First, whether the role diversity is given in a particular context does have effects on groups and the individual members therein. Second, if such effects exist, it seeks to explore the processes and mechanisms they are based on. Both questions are addressed from different perspectives in the three main chapters of this dissertation. Chapter 5 contains two meta-analyses on the effects of diversity beliefs and diversity climates. Diversity beliefs are individual attitudes that describe the degree to which diversity is ascribed an instrumental value for achieving beneficial outcomes or avoiding detrimental ones. Diversity climates depict such a value of diversity on the group-level. Building on the social identity approach, I explain how diversity beliefs and climates can obviate diversity’s detrimental effects and foster beneficial ones. As both diversity beliefs and climates can cause such effects, they are considered together in the main analyses in the chapter. In the first part of the chapter, a meta-analysis on these moderator effects of diversity beliefs/climates is presented (k = 23). The majority of studies that addressed such effects reported significant results. The patterns of these results showed that, in general, diversity will be more positively related to beneficial outcomes the more it is valued. However, the analysis also revealed that there are at least two types of patterns of this moderation. So far, it cannot be explained which pattern will occur under what circumstances. In the second part of the chapter, a meta-analysis on the main effects of diversity beliefs/climates on beneficial outcomes is presented (k = 71). These effects did not receive much attention in the primary studies. Based on the social identity approach and the fact that diversity is a ubiquitous feature of modern organizations, I argue that they are important nonetheless. The meta-analysis revealed a significant positive main effect of diversity beliefs on beneficial outcomes (r = .25; p < .0001). However, the effect sizes varied considerably across studies. Both moderator and main effects were found across a broad array of outcomes, study designs, levels of analysis, and operationalizations of the constructs involved. They were found irrespective of whether diversity beliefs or diversity climates were considered. The heterogeneity of results in the meta-analyses suggests that there is still much to be learned about when differences in vantage points from which people engage with diversity will have an effect and about the processes that underlie these effects. Chapter 6 is, therefore, predominantly concerned with these underlying processes. Most of the previous research has treated pro-diversity beliefs and pro-similarity beliefs as opposite poles of one underlying continuum. There is, however, evidence that people can hold both types of beliefs simultaneously. Therefore, I propose that both diversity in certain aspects and similarity in other aspects can simultaneously constitute valid and valued parts of an organization’s identity, and that, hence, identifying with the organization can create two forms of solidarity among the employees: organic solidarity – based on meaningfully and synergistically interrelated differences, and mechanic solidarity – based on the common ground that all employees share. Furthermore, I propose that both forms of solidarity can coexist and that both are positively related to the quality of collaboration within the organization. Thus, organizational identification is proposed to influence quality of collaboration indirectly through both organic and mechanic solidarity. These propositions were tested with regard to the collaboration of different teams within two organizations: a German university (Study 1, N = 699) and a Taiwanese hospital (Study 2, N = 591). The results from both studies confirm the predictions. However, the relative importance of each form of solidarity varied across study contexts and across different facets of the quality of collaboration. Chapter 7 also builds on the findings from the meta-analyses and is again predominantly focussed on the processes underlying the effects of diversity beliefs and diversity climates, yet from a different angle. Previously, diversity beliefs and climates have often been discussed with regard to their potential to influence whether diversity will lead to more and deeper elaboration of information within the group. In chapter 7 a theoretical model is developed that complements these cognitive processes by addressing the emotional side of diverse groups. Central to the model is the assumption that group diversity can stimulate group members to engage with each other emotionally, resulting in higher levels of state affective empathy: an emotional state which arises from the comprehension and apprehension of fellow group members’ emotional state. State affective empathy, in turn, is known to lead to a variety of beneficial team processes that can ultimately enhance individual and group-level performance. Thus, the central proposition of the model is that the relationship between diversity and performance is mediated through state affective empathy. The other propositions in the model specify moderators that determine when diversity will indeed have this empathy-stimulating effect. Diversity beliefs and climates are considered second-order moderators that shape the relationship between diversity and empathy through their influence on the first-order moderators. In general, it is proposed that diversity is related to empathy more positively if it is valued by the group or its members. In summary, the results from the meta-analyses in chapter 5, the results from the field studies in chapter 6, and the theoretical arguments presented in chapter 7 can be interpreted such that differences in vantage points from which people engage with diversity can indeed affect groups and their members. Therefore, the first research question of the present dissertation can be answered affirmatively from three different perspectives. However, it also became clear that there is still much uncertainty about the mechanisms underlying these effects. In line with the second research question of the present dissertation, these mechanisms were examined more closely in chapter 6 and 7. The field studies in chapter 6 highlighted the role of identification as the driving force behind the effects of different vantage points on diversity. Furthermore, they also corroborate the proposition that valuing diversity and valuing similarity can be co-occurring phenomena that both influence the collaboration within the group positively. The theoretical model presented in chapter 7 opens up a new emotional way in which diversity beliefs and climates can influence whether diversity will lead to better or worse performance. In sum, therefore, also with regard to the second research question of the present dissertation, progress has been made.
In human neuroscientific research, there has been an increasing interest in how the brain computes the value of an anticipated outcome. However, evidence is still missing about which valuation related brain regions are modulated by the proximity to an expected goal and the previously invested effort to reach a goal. The aim of this dissertation is to investigate the effects of goal proximity and invested effort on valuation related regions in the human brain. We addressed this question in two fMRI studies by integrating a commonly used reward anticipation task in differential versions of a Multitrial Reward Schedule Paradigm. In both experiments, subjects had to perform consecutive reward anticipation tasks under two different reward contingencies: in the delayed condition, participants received a monetary reward only after successful completion of multiple consecutive trials. In the immediate condition, money was earned after every successful trial. In the first study, we could demonstrate that the rostral cingulate zone of the posterior medial frontal cortex signals action value contingent to goal proximity, thereby replicating neurophysiological findings about goal proximity signals in a homologous region in non-human primates. The findings of the second study imply that brain regions associated with general cognitive control processes are modulated by previous effort investment. Furthermore, we found the posterior lateral prefrontal cortex and the orbitofrontal cortex to be involved in coding for the effort-based context of a situation. In sum, these results extend the role of the human rostral cingulate zone in outcome evaluation to the continuous updating of action values over a course of action steps based on the proximity to the expected reward. Furthermore, we tentatively suggest that previous effort investment invokes processes under the control of the executive system, and that posterior lateral prefrontal cortex and the orbitofrontal cortex are involved in an effort-based context representation that can be used for outcome evaluation that is dependent on the characteristics of the current situation.
In Deutschland hängen Bildungschancen wie in kaum einem anderen Land vom Bildungsstatus der Herkunftsfamilie ab. Vom Ideal einer Chancengleichheit sind wir weit entfernt. So verlässt beispielsweise jedes vierte Kind mit Migrationshintergrund die Schule ohne Abschluss. Viele Kinder aus sozial schwierigen Verhältnissen enden wie meist schon ihre Eltern in der Arbeitslosigkeit und in einem Leben am Rande der Gesellschaft.
Während Bildungspolitiker heftig über die Abschaffung der Hauptschule streiten und Hamburger Bürger sich per Volksentscheid für den Erhalt des Gymnasiums ab Klasse 5 einsetzen, sind sich die meisten Bildungsforscher einig: Entscheidend ist nicht, wo, sondern wie Kinder unterrichtet und betreut werden. Wie kann es gelingen, pädagogische Interventionen den unterschiedlichen Lernvoraussetzungen so anzupassen, dass möglichst alle Schülerinnen und Schüler optimal gefördert werden? Um das herauszufi nden, bedarf es intensiver Anstrengungen in der Lehr-Lernforschung, wie sie in Frankfurt im Forschungszentrum IDeA unternommen werden.
Sie sind nicht weniger intelligent als ihre gleichaltrigen Mitschüler, und doch sind ihre schulischen Leistungen meist schlechter: Kinder, die unter einer Störung mit Aufmerksamkeitsdefi zit und Hyperaktivität (ADHS) leiden, haben es schwer im Schulsystem. Wie können sie lernen, ihre Gefühle, Gedanken und Handlungen bewusst zu beeinfl ussen und sich nicht ständig ablenken zu lassen? Frankfurter Studien zeigen zum Beispiel, dass konkrete "Wenn-Dann-Pläne" ihre Konzentrationsfähigkeit deutlich verbessern können.
In den vorgelegten drei Studien wurden Lebenserzählungen zum einen über die Adoleszenzentwicklung und zum anderen im Adult Attachment Interview textanalytisch, über semantisch-syntaktische Kodes, untersucht. Die ersten beiden Studien untersuchen die Variablen globale Kohärenz, bzw. narrative Verantwortungsübernahme in Lebenserzählungen von 102 Kindern, Jugendlichen und jungen Erwachsenen (8, 12, 16 und 20 Jahre). Hypothesen sind, dass beide Variablen in der Adoleszenz aufgrund der Identitätsentwicklung ansteigen. Die Haupthypothesen zeigen sich als bestätigt. In der dritten Studie wird die narrative Verantwortungsübernahme anhand einer Sekundäranalyse von Adult Attachment Interviews von 28 Frauen untersucht. Die Hypothese lautet, dass sichere Bindungsrepräsentationen mehr narrative Verantwortungsübernahme zeigen als unsichere Bindungsrepräsentationen und dass unsichere Bindungsrepräsentationen mehr narrative Abstufungen von Verantwortung zeigen als sichere Bindungsrepräsentationen. Während die erste Hypothese keine signifikanten Ergebnisse zeigt, stellt sich die zweite Hypothese als bestätigt dar. Die Ergebnisse werden in den ersten beiden Studien in Bezug auf die Identitätsentwicklung und in der dritten Studie im Zusammenhang mit einer Grammatik von unsicherer Bindung diskutiert. Enth. 3 Sonderabdr. aus verschiedenen Zeitschr: Developmental Psychology 2008, Vol. 44, No. 3, 707–721 The Development of Global Coherence in Life Narratives Across Adolescence: Temporal, Causal, and Thematic Aspects de Silveira, Cybèle and Habermas, Tilmann(2011) 'Narrative Means to Manage Responsibility in Life Narratives Across Adolescence', The Journal of Genetic Psychology, 172: 1, 1 — 20 de Silveira, Cybèle and Habermas, Tilmann(2010) 'Narrative Grading of Responsibility of Secure and Insecure Attachment Representations in the Adult Attachment Interview'
Background: Although literature provides support for cognitive behavioral therapy (CBT) as an efficacious intervention for social phobia, more research is needed to improve treatments for children. Methods: Forty four Caucasian children (ages 8-14) meeting diagnostic criteria of social phobia according to the Diagnostic and Statistical Manual of Mental Disorders (4th ed.; APA, 1994) were randomly allocated to either a newly developed CBT program focusing on cognition according to the model of Clark and Wells (n = 21) or a wait-list control group (n = 23). The primary outcome measure was clinical improvement. Secondary outcomes included improvements in anxiety coping, dysfunctional cognitions, interaction frequency and comorbid symptoms. Outcome measures included child report and clinican completed measures as well as a diagnostic interview. Results: Significant differences between treatment participants (4 dropouts) and controls (2 dropouts) were observed at post test on the German version of the Social Phobia and Anxiety Inventory for Children. Furthermore, in the treatment group, significantly more children were free of diagnosis than in wait-list group at post-test. Additional child completed and clinician completed measures support the results. Discussion: The study is a first step towards investigating whether CBT focusing on cognition is efficacious in treating children with social phobia. Future research will need to compare this treatment to an active treatment group. There remain the questions of whether the effect of the treatment is specific to the disorder and whether the underlying theoretical model is adequate. Conclusion: Preliminary support is provided for the efficacy of the cognitive behavioral treatment focusing on cognition in socially phobic children. Active comparators should be established with other evidence-based CBT programs for anxiety disorders, which differ significantly in their dosage and type of cognitive interventions from those of the manual under evaluation (e.g. Coping Cat).
Forgotten features of head zones and their relation to diagnostically relevant acupuncture points
(2011)
In the 1890s Sir Henry Head discovered certain areas of the skin that develop tenderness (allodynia) in the course of visceral disease. These areas were later termed ‘Head zones’. In addition, he also emphasized the existence of specific points within these zones, that he called ‘maximum points’, a finding that seems to be almost forgotten today. We hypothesized that two important groups of acupuncture points, the diagnostically relevant Mu and Shu points, spatially and functionally coincide with these maximum points to a large extent. A comparison of Head's papers with the Huang Di Neijing (Yellow Thearch's Inner Classic) and the Zhen Jiu Jia Yi Jing (Systematic Classic of Acupuncture and Moxibustion), two of the oldest still extant Chinese sources on acupuncture, revealed astonishing parallels between the two concepts regarding both point locations and functional aspects. These findings suggest that the Chinese discovery of viscerocutaneous reflexes preceded the discovery in the West by more than 2000 years. Furthermore, the fact that Chinese medicine uses Mu and Shu points not only diagnostically but also therapeutically may give us new insights into the underlying mechanisms of acupuncture.