Filtern
Erscheinungsjahr
Dokumenttyp
- Dissertation (64)
- Wissenschaftlicher Artikel (30)
Sprache
- Englisch (94) (entfernen)
Schlagworte
- Stress (22)
- Hydrocortison (13)
- Cortisol (9)
- cortisol (9)
- stress (7)
- Lernen (6)
- Physiologische Psychologie (6)
- Aufmerksamkeit (5)
- Depression (4)
- Elektroencephalographie (4)
- Funktionelle NMR-Tomographie (4)
- Kognition (4)
- Lebensmittel (4)
- Neuroendokrines System (4)
- Stressreaktion (4)
- fMRI (4)
- Affekt (3)
- Aggression (3)
- Gedächtnis (3)
- Langzeitgedächtnis (3)
- Memory (3)
- Psychotherapie (3)
- Schmerz (3)
- Selbstbild (3)
- episodic memory (3)
- long-term memory (3)
- Ambivalenz (2)
- Arbeitsgedächtnis (2)
- Augenfolgebewegung (2)
- Brustkrebs (2)
- Distractor-Response Binding (2)
- Dopamin (2)
- Einstellung (2)
- Elektroencephalogramm (2)
- Emotion (2)
- Emotionsregulation (2)
- Episodisches Gedächtnis (2)
- Ereigniskorreliertes Potenzial (2)
- Essstörung (2)
- Evaluation (2)
- Evaluative Konditionierung (2)
- Fibromyalgie (2)
- Gefühl (2)
- Gehirn (2)
- Genanalyse (2)
- Genexpression (2)
- Glucocorticosteroide (2)
- Glucocorticosteroidrezeptor (2)
- HPA axis (2)
- Humangenetik (2)
- Hypothalamus-Hypophysen-Nebennierenrinden-Achse (2)
- Insulin (2)
- Interaktion (2)
- Interozeption (2)
- Kognitive Psychologie (2)
- Learning (2)
- Partnerwahl (2)
- Persönlichkeitsstörung (2)
- Prognose (2)
- Psychobiologie (2)
- Psychological stress (2)
- Rückmeldung (2)
- Schizophrenie (2)
- Schreckreaktion (2)
- Selbstkontrolle (2)
- Stressor (2)
- Therapieerfolg (2)
- Vegetatives Nervensystem (2)
- Vergessen (2)
- academic self-concept (2)
- affective startle modulation (2)
- alternative Transkriptionsvarianten (2)
- alternative transcription variant (2)
- ambivalence (2)
- attitudes (2)
- behavioral genetics (2)
- directed forgetting (2)
- dopamine (2)
- evaluative conditioning (2)
- fibromyalgia (2)
- glucocorticoid receptor (2)
- intervention (2)
- mating preferences (2)
- pain (2)
- psychology (2)
- selective attention (2)
- (ADHD (1)
- 2D DIGE (1)
- 5' UTR (1)
- ACC (1)
- ANS (1)
- Abhängigkeit (1)
- Acetylcholin (1)
- Action control (1)
- Adaptives System (1)
- Affect (1)
- Affektive Schreckreiz-Modulation (1)
- Affektive Startle Modulation (1)
- Affektstörung (1)
- Alter (1)
- Ambivalence (1)
- Angststörung (1)
- Annäherungs-Vermeidungs-Motivation (1)
- Anthropometrie (1)
- Approach-avoidance motivation (1)
- Arbeit (1)
- Assoziatives Lernen (1)
- Aufmerksamkeits-Defizit-Syndrom (1)
- Ausdauer (1)
- Auswahl (1)
- Autismus (1)
- Baroreflex (1)
- Bauchfett (1)
- Beeinflussung (1)
- Begabtenförderung (1)
- Behalten (1)
- Behavioural methods (1)
- Beurteilungsfehler (1)
- Binge-eating Disorder (1)
- Bipolar Disorder (1)
- Bipolare Störung (1)
- Birth weight (1)
- Blinkreflex (1)
- Blinzelreflex (1)
- Borderline Personality Disorder (1)
- Borderline-Persönlichkeitsstörung (1)
- Brain (1)
- Bulimie (1)
- Burnout (1)
- Burnout-Syndrom (1)
- C15orf53 (1)
- CASL (1)
- CBG (1)
- CBT (1)
- COMT Val158Met (1)
- Care (1)
- Catecholmethyltransferase <Catechol-0-Methyltransferase> (1)
- Central Nervous System (1)
- Change (1)
- Chromosom 15 (1)
- Chromosom 22 (1)
- Cingulum (1)
- Cingulum Cerebri (1)
- Cognition (1)
- Cold Pressor Test (1)
- Coming-out (1)
- Conceptual Endophenotypes (1)
- Conduct disorder (1)
- Construal Level Theorie (1)
- Construal Level Theory (1)
- Consumer need for uniqueness (1)
- Continuity (1)
- Control theory (1)
- Corticosteroid-bindendes Globulin (1)
- Corticosteroidrezeptor (1)
- Cortisol-Aufwach-Reaktion (1)
- Cytokine (1)
- Das circadiane System (1)
- Diagnostische Urteilskompetenz (1)
- Differentielle Genexpression (1)
- Dissonance (1)
- Distraktor-Reaktionsbindung (1)
- Distraktor-Verarbeitung (1)
- Distraktorverarbeitung (1)
- EEG (1)
- ERP (1)
- Ecological Momentary Assessment (1)
- Einstellungsforschung (1)
- Elektroenzephalogramm (1)
- Elektrokardiogramm (1)
- Emotions (1)
- Empfindung (1)
- Encodierung (1)
- Entscheidung (1)
- Entwicklung (1)
- Enzym (1)
- Enzyme (1)
- Epigenetik (1)
- Ereigniskorreliertes Potential (1)
- Ergebnis (1)
- Erwartung (1)
- Erzählung (1)
- Essgewohnheit (1)
- Essverhalten (1)
- Event file (1)
- Event-File (1)
- Exekuitive Funktion (1)
- Exekutive Funktionen (1)
- Experiment (1)
- Extraversion (1)
- F0 (1)
- FKBP51 (1)
- Fahrassistenzsystem (1)
- Faktorenanalyse (1)
- Fear (1)
- Feedback (1)
- Feinkartierung (1)
- Fettsucht (1)
- Fetus (1)
- Fissurisation (1)
- Flexibilität (1)
- Fluoreszenzmikroskopie (1)
- Food pictures (1)
- Frequenzbandkopplungen (1)
- Funktionalität (1)
- Funktionelle Kernspintomographie (1)
- Furcht (1)
- Fähigkeitsselbstkonzepte (1)
- GR (1)
- Gamification (1)
- Gedächtnisrepräsentation (1)
- Gedächtnistest (1)
- Gegenstimulation (1)
- Genauigkeit (1)
- Generationsbeziehung (1)
- Genetik (1)
- Geneva Emotional Competence Test (1)
- Gesichtsfeld (1)
- Glucocorticoid Receptor (GR) (1)
- Glucocorticoidrezeptor (1)
- Glucocorticoids (1)
- Glukokortikoidrezeptor (1)
- Grundfrequenz (1)
- Grundschullehrer (1)
- Gyrifikation (1)
- HPA (1)
- HPA-Achse (1)
- Habituation (1)
- Handlungsregulation (1)
- Haushalt (1)
- Heart rate (1)
- Hemisphärendominanz (1)
- Herztransplantation (1)
- Hippocampus (1)
- Hippocampus Aktivierung (1)
- Hippocampus Atrophie (1)
- Hippocampus Volumen (1)
- Hirnforschung (1)
- Hirnfunktion (1)
- Human (1)
- Human behaviour (1)
- Hypothalamic-pituitary-adrenocortical axis (1)
- Immunsystem (1)
- Implizites Lernen (1)
- Implizites Sequenzlernen (1)
- Impulsivität (1)
- Individualisierte Medizin (1)
- Individualisierung (1)
- Information (1)
- Information Retrieval (1)
- Informationsverarbeitung (1)
- Infusion (1)
- Inhibition (1)
- Inhibitorische Kontrolle (1)
- Intelligence Structure Battery (1)
- Intelligence profiles (1)
- Intelligenz (1)
- Intelligenztest (1)
- Intention (1)
- Interoception (1)
- Interpersonale Kommunikation (1)
- Intranasal insulin (1)
- Intrusionen (1)
- Isolation <Soziologie> (1)
- Jugend (1)
- Kaltwasserstresstest (1)
- Kaltwasssertest (1)
- Kardiovaskuläre Krankheit (1)
- Kernspintomographie (1)
- Kind (1)
- Klassiche Lidschlagkonditionierung (1)
- Klassische Konditionierung (1)
- Knowledge (1)
- Koerperwahrnehmung (1)
- Kognitive Entwicklung (1)
- Kognitive Verhaltenstherapie (1)
- Konditionierung (1)
- Kontrollierte Therapiestudie (1)
- Konzeptuelle Endophänotypen (1)
- Kopplungs- und Mutationsanalysen (1)
- Kortex (1)
- Kunststoff (1)
- Körpertherapie (1)
- LG children (1)
- Leben (1)
- Lebensqualität (1)
- Lerntechnik (1)
- Literatur (1)
- Long-term memory (1)
- Lymphozyt (1)
- MALDI-TOF MS (1)
- MLC1 (1)
- MR (1)
- Makrophage (1)
- Mann (1)
- Mass Customization (1)
- Mathematik (1)
- Meat Consumption (1)
- Meat Paradox (1)
- Mensch (1)
- Menstruationszyklus (1)
- Meta-Analyse (1)
- Meta-Analysis (1)
- Metabolism (1)
- Methylierung und SNPs (1)
- Methylphenidat (1)
- Milde Depression (1)
- Mindesthaltbarkeitsdatum (1)
- Mineralokortikoidrezeptor (1)
- Moderator (1)
- Moderators and mediators (1)
- Modulation (1)
- Monozyt (1)
- Mortality Salience (1)
- Mortalitätssalienz (1)
- Motor mimicry (1)
- MouseTracker (1)
- Mutation (1)
- Männlichkeit (1)
- NMR-Spektroskopie (1)
- Netzwerkanalyse (1)
- Neuropattern (1)
- Nuklearrezeptoren (1)
- Orbicularis-oculi-Reflex (1)
- P-Glykoprotein (1)
- PERIOD Gene (1)
- PERIOD gene (1)
- PERIOD genes (1)
- PTSD (1)
- Patient (1)
- Patients (1)
- Perfektionismus (1)
- Perfusion (1)
- Personalisierte Psychotherapie (1)
- Personalisierung (1)
- Personalized Medicine (1)
- Personalized mental health (1)
- Phasen-Amplituden-Kopplung (1)
- Physical activity (1)
- Plazenta (1)
- Polymorphismus (1)
- Positive affect (1)
- Positiver Affekt (1)
- Posttraumatisches Stresssyndrom (1)
- Precision mental health (1)
- Pressorezeptor (1)
- Problemlösen (1)
- Prognosis (1)
- Programm (1)
- Promotorregion (1)
- Prosa (1)
- Prosocial behavior (1)
- Proteomanalyse (1)
- Provokation (1)
- Präferenz (1)
- Präpulsinhibierung (1)
- Psychiatric genetics (1)
- Psychische Störung (1)
- Psychisches Trauma (1)
- Psychologiestudierende (1)
- Psychologiestudium (1)
- Psychologische Diagnostik (1)
- Psychologische Distanz (1)
- Psychometrie (1)
- Psychometrischer Intelligenztest (1)
- Psychophysiology (1)
- Psychotherapeutische Versorgung (1)
- Pulsatilität (1)
- Pädagogische Diagnostik (1)
- RCT (1)
- Reaktion (1)
- Reiz-Reaktions Bindung (1)
- Reizverarbeitung (1)
- Reliabilität (1)
- Routine outcome monitoring (1)
- SNP (1)
- Sakkade (1)
- Schizophrenia (1)
- Schreckreflex (1)
- Schule (1)
- Schullaufbahnempfehlung (1)
- Schulleistung (1)
- Schulzeugnis (1)
- Schwangersch (1)
- Schwangerschaft (1)
- Schweißabsonderung (1)
- Sekundärkrankheit (1)
- Selbsteinschätzung (1)
- Selbstkonzept (1)
- Selbstregulation (1)
- Selbstwert (1)
- Selbstwertgefühl (1)
- Selbstwirksamkeit (1)
- Selbstwirksamkeitserwartung (1)
- Selective attention (1)
- Selektion (1)
- Selektivität (1)
- Self-Regulation (1)
- Smoking) (1)
- Social anxiety disorder (1)
- Somatic experiencing (1)
- Sozialangst (1)
- Sozialer Stress (1)
- Sozialpsychologie (1)
- Sozialverhalten (1)
- Spatial learning (1)
- Speichel (1)
- Sprachverarbeitung (1)
- Stability (1)
- Startle modulation (1)
- Startle reflex (1)
- Statistik (1)
- Stereotyp (1)
- Steroidhormonrezeptor (1)
- Stillen (1)
- Stimme (1)
- Stimulus-Response binding (1)
- Stimulus-response learning (1)
- Struktur (1)
- Subarachnoidalblutung (1)
- Sympathikus (1)
- Test-retest (1)
- Testen (1)
- Testergebnis (1)
- Testosteron (1)
- Thalamus (1)
- Therapieabbruch (1)
- Thermal stresses (1)
- Transkript (1)
- Transkription <Genetik> (1)
- Umweltbewusstsein (1)
- Universal Eating Monitor (1)
- Unsicherheit (1)
- Unterkörper Unterdruck (1)
- Unterrichtsfach (1)
- Vagus (1)
- Validierung (1)
- Vater (1)
- Vegetarianism (1)
- Verbesserung (1)
- Verbraucherverhalten (1)
- Verhaltensgenetik (1)
- Verhaltensmuster (1)
- Verhaltensstörung (1)
- Verlangen (1)
- Vermeidung (1)
- Verpackung (1)
- Verschwendung (1)
- Videospiel (1)
- Visceral perception (1)
- Visuelle Aufmerksamkeit (1)
- Viszerale Wahrnehmung (1)
- Vorsorge (1)
- Wandel (1)
- Wartezeit (1)
- Willenskraft (1)
- Wirkung (1)
- Wissen (1)
- Work Stress (1)
- Working memory (1)
- Zeit (1)
- Zentralnervensystem (1)
- Zuckergehalt (1)
- Zytokin (1)
- acetylcholine (1)
- action control (1)
- adaptive hypermedia (1)
- adolescents (1)
- affect (1)
- age stereotypes (1)
- akademisches Selbstkonzept (1)
- analysistransplantation (1)
- anterior cingulate (1)
- arterial spin labeling (1)
- associative learning (1)
- attitude formation (1)
- automatische Handlungsplanung (1)
- automatische Reizverarbeitung (1)
- baroreceptor (1)
- best before (1)
- biases in judgement (1)
- blood oxygen level dependent (BOLD) contrast (1)
- body composition (1)
- bottom-up-therapy (1)
- brain (1)
- bulimia (1)
- central adiposity (1)
- cerebral blood flow (1)
- chronic stress (1)
- chronischer Stress (1)
- circadian clock genes (1)
- circadian clock system (1)
- cognition (1)
- cognitive control (1)
- cold pressor (1)
- coming out (or disclosure) (1)
- cortex (1)
- corticosteroid receptor (1)
- cortisol response to awakening (1)
- counter-stimulation (1)
- cross-frequency coupling (1)
- crystallized abilities (1)
- customer loyalty (1)
- cytokine (1)
- cytokines (1)
- dACC (1)
- date labeling (1)
- decision making (1)
- depression (1)
- development (1)
- die circadiane Uhr-Gene (1)
- distractor processing (1)
- distress (1)
- domestic food waste (1)
- driver assistance system (1)
- dual task interference (1)
- early response (1)
- eating behavior (1)
- eating behaviour (1)
- ecological momentary assessment (1)
- educational assessment (1)
- effectiveness (1)
- efficacy (1)
- electrocardiogram (1)
- electroencephalogram (1)
- emotion regulation (1)
- emotional intelligence (1)
- empirical evaluation (1)
- encoding (1)
- epigenetic programming (1)
- evaluation (1)
- evaluation framework (1)
- event file (1)
- executive functions (1)
- exekutive Funktionen (1)
- eyeblink conditioning (1)
- fMRT (1)
- factor analysis (1)
- familial risk (1)
- fathers (1)
- fine mapping (1)
- fissurization (1)
- fluid abilities (1)
- food preference (1)
- functional MRI (1)
- functional specialisation of hemispheres (1)
- funktionelle NMR-Tomographie (1)
- games, experimental (1)
- gene expression (1)
- genetics (1)
- glucocorticoids (1)
- glycaemic index (1)
- growth mixture modeling (1)
- heart failure (1)
- hippocampal atrophy (1)
- hippocampal volume assessment (1)
- homosexuality (1)
- hypothalamic-pituitary-adrenal axis (1)
- hypothalamo-pituitary-adrenal-axis (1)
- hypothalamus-pituitary-adrenal axis (1)
- immune system (1)
- immunity (1)
- implicit learning (1)
- impulsivity (1)
- information processing (1)
- inhibitory control (1)
- interference (1)
- intergenerational programs (1)
- interoception (1)
- intrusions (1)
- judgement accuracy (1)
- kognitive Kontrolle (1)
- language processing (1)
- learning (1)
- linkage and mutational analysis (1)
- lower body negative pressure (1)
- lymphocytes (1)
- macrophages (1)
- maternal care (1)
- mean vector length (1)
- membrane glucocorticoid receptor (1)
- membraner Glucocorticoidrezeptor (1)
- memory (1)
- memory representation (1)
- menstrual cycle (1)
- methylation and SNPs (1)
- methylphenidate (1)
- midcingulate cortex (1)
- mineralocorticoid receptor (1)
- mismatch negativity (1)
- modulation (1)
- modulation index (1)
- monocytes (1)
- motion energy analysis (1)
- natural killer cells (1)
- natürliche Killerzellen (1)
- neuroendocrine system (1)
- neuroimaging (1)
- nicht-genomische Effekte (1)
- non-genomic effects (1)
- nonverbal synchrony (1)
- norepinephrine (1)
- nuclear receptor (1)
- nucleus accumbens (1)
- obesity (1)
- older adults (1)
- p-glycoprotein (1)
- patient-focused psychotherapy research (1)
- patienten-orientierte Psychotherapieforschung (1)
- perception (1)
- periodic catatonia (1)
- periodische Katatonie (1)
- personalized psychotherapy (1)
- phase-amplitude coupling (1)
- placenta (1)
- plastic (1)
- post-transcriptional regulation (1)
- post-transkriptionelle Regulierung (1)
- post-traumatic stress disorder (1)
- postnatal stress factors (1)
- postnatale Stressfaktoren (1)
- posttraumatic stress disorder (1)
- prenatal adversity (1)
- prenatal programming (1)
- prenatal stress (1)
- prenatal stress factors (1)
- prenatal tobacco exposure (1)
- prepulse inhibition (1)
- promoter region (1)
- proof of concept study (1)
- proteomics (1)
- provocation (1)
- pränatale Programmierung (1)
- pränatale Risikofaktoren (1)
- pränatale Stressfaktoren (1)
- pränatale Tabakexposition (1)
- pränataler Stress (1)
- psychological distance (1)
- psychology and behaviorsocial isolation (1)
- psychology students (1)
- psychometric validation (1)
- pulsatility (1)
- quantitative sensory testing (1)
- retrieval practice (1)
- risk factors (1)
- routine care (1)
- saccade (1)
- salivary alpha-amylase (1)
- school (1)
- school performance (1)
- school subject (1)
- selection (1)
- selective forgetting (1)
- selektive Aufmerksamkeit (1)
- self-concept (1)
- self-efficacy (1)
- self-esteem (1)
- self-perception (1)
- simulation study (1)
- social contactssurvival (1)
- social self-concept (1)
- somatische Komorbiditäten (1)
- soziale Selbstkonzepte (1)
- stress hyporesponsive period (1)
- stress reaction (1)
- structure (1)
- subarachnoid haemorrhage (1)
- substance abuse (1)
- teacher judgement (1)
- teachers (1)
- testing (1)
- text memory (1)
- trauma therapy (1)
- uncertainty (1)
- uniqueness seeking (1)
- user modeling (1)
- vagus (1)
- video games (1)
- visceral awareness (1)
- visual change detection (1)
- visuelle Wahrnehmung (1)
- visueller Mismatch (1)
- viszerale Empfindung (1)
- voice (1)
- zerebraler Blutfluss (1)
- Ätiologie (1)
- Überleben (1)
- Übung (1)
Institut
- Psychologie (94) (entfernen)
The stress hormone cortisol as the end-product of the hypothalamic-pituitary-adrenal (HPA) axis has been found to play a crucial role in the release of aggressive behavior (Kruk et al., 2004; Böhnke et al., 2010). In order to further explore potential mechanisms underlying the relationship between stress and aggression, such as changes in (social) information processing, we conducted two experimental studies that are presented in this thesis. In both studies, acute stress was induced by means of the Socially Evaluated Cold Pressor Test (SECP) designed by Schwabe et al. (2008). Stressed participants were classified as either cortisol responders or nonresponders depending on their rise in cortisol following the stressor. Moreover, basal HPA axis activity was measured prior to the experimental sessions and EEG was recorded throughout the experiments. The first study dealt with the influence of acute stress on cognitive control processes. 41 healthy male participants were assigned to either the stress condition or the non-stressful control procedure of the SECP. Before as well as after the stress induction, all participants performed a cued task-switching paradigm in order to measure cognitive control processes. Results revealed a significant influence of acute and basal cortisol levels, respectively, on the motor preparation of the upcoming behavioral response, that was reflected in changes in the magnitude of the terminal Contingent Negative Variation (CNV). In the second study, the effect of acute stress and subsequent social provocation on approach-avoidance motivation was examined. 72 healthy students (36 males, 36 females) took part in the study. They performed an approach-avoidance task, using emotional facial expressions as stimuli, before as well as after the experimental manipulation of acute stress (again via the SECP) and social provocation realized by means of the Taylor Aggression Paradigm (Taylor, 1967). Additionally to salivary cortisol, testosterone samples were collected at several points in time during the experimental session. Results indicated a positive relationship between acute testosterone levels and the motivation to approach social threat stimuli in highly provoked cortisol responders. Similar results were found when the testosterone-to-cortisol ratio at baseline was taken into account instead of acute testosterone levels. Moreover, brain activity during the approach-avoidance task was significantly influenced by acute stress and social provocation, as reflected in reductions of early (P2) as well as of later (P3) ERP components in highly provoked cortisol responders. This may indicate a less accurate, rapid processing of socially relevant stimuli due to an acute increase in cortisol and subsequent social provocation. In conclusion, the two studies presented in this thesis provide evidence for significant changes in information processing due to acute stress, basal cortisol levels and social provocation, suggesting an enhanced preparation for a rapid behavioral response in the sense of a fight-or-flight reaction. These results confirm the model of Kruk et al. (2004) proposing a mediating role of changed information processes in the stress-aggression-link.
Every day we are exposed to a large set of appetitive food cues, mostly of high caloric, high carbohydrate content. Environmental factors like food cue exposition can impact eating behavior, by triggering anticipatory endocrinal responses and reinforcing the reward value of food. Additionally, it has been shown that eating behavior is largely influence by neuroendocrine factors. Energy homeostasis is of great importance for survival in all animal species. It is challenged under the state of food deprivation which is considered to be a metabolic stressor. Interestingly, the systems regulating stress and food intake share neural circuits. Adrenal glucocorticoids, as cortisol, and the pancreatic hormone insulin have been shown to be crucial to maintain catabolic and anabolic balance. Cortisol and insulin can cross the blood-brain barrier and interact with receptors distributed throughout the brain, influencing appetite and eating behavior. At the same time, these hormones have an important impact on the stress response. The aim of the current work is to broaden the knowledge on reward related food cue processing. With that purpose, we studied how food cue processing is influenced by food deprivation in women (in different phases of the menstrual cycle) and men. Furthermore, we investigated the impact of the stress/metabolic hormones, insulin and cortisol, at neural sites important for energy metabolism and in the processing of visual food cues. The Chapter I of this thesis details the underlying mechanisms of the startle response and its application in the investigation of food cue processing. Moreover, it describes the effects of food deprivation and of the stress-metabolic hormones insulin and cortisol in reward related processing of food cues. It explains the rationale for the studies presented in Chapter II-IV and describes their main findings. A general discussion of the results and recommendations for future research is given. In the study described in Chapter II, startle methodology was used to study the impact of food deprivation in the processing of reward related food cues. Women in different phases of the menstrual cycle and men were studied, in order to address potential effects of sex and menstrual cycle. All participants were studied either satiated or food deprived. Food deprivation provoked enhanced acoustic startle (ASR) response during foreground presentation of visual food cues. Sex and menstrual cycle did not influence this effect. The startle pattern towards food cues during fasting can be explained by a frustrative nonreward effect (FNR), driven by the impossibility to consume the exposed food. In Chapter III, a study is described, which was carried out to explore the central effects of insulin and cortisol, using continuous arterial spin labeling to map cerebral blood flow patterns. Following standardized periods of fasting, male participants received either intranasal insulin, oral cortisol, both, or placebo. Intranasal insulin increased resting regional cerebral blood flow in the putamen and insular cortex, structures that are involved in the regulation of eating behavior. Neither cortisol nor interaction effects were found. These results demonstrate that insulin exerts an action in metabolic centers during resting state, which is not affected by glucocorticoids. The study described in Chapter IV uses a similar pharmacological manipulation as the one presented in Chapter III, while assessing processing of reward related food cues through the startle paradigm validated in Chapter II. A sample of men was studied during short-term food deprivation. Considering the importance of both cortisol and insulin in glucose metabolism, food pictures were divided by glycemic index. Cortisol administration enhanced ASR during foreground presentation of "high glycemic" food pictures. This result suggests that cortisol provokes an increase in reward value of high glycemic food cues, which is congruent with previous research on stress and food consumption. This thesis gives support to the FNR hypothesis towards food cues during states of deprivation. Furthermore, it highlights the potential effects of stress related hormones in metabolism-connected neuronal structures, and in the reward related mechanisms of food cue processing. In a society marked by increased food exposure and availability, alongside with increased stress, it is important to better understand the impact of food exposition and its interaction with relevant hormones. This thesis contributes to the knowledge in this field. More research in this direction is needed.
The benefits of prosocial power motivation in leadership: Action orientation fosters a win-win
(2023)
Power motivation is considered a key component of successful leadership. Based on its dualistic nature, the need for power (nPower) can be expressed in a dominant or a prosocial manner. Whereas dominant motivation is associated with antisocial behaviors, prosocial motivation is characterized by more benevolent actions (e.g., helping, guiding). Prosocial enactment of the power motive has been linked to a wide range of beneficial outcomes, yet less has been investigated what determines a prosocial enactment of the power motive. According to Personality Systems Interactions (PSI) theory, action orientation (i.e., the ability to self-regulate affect) promotes prosocial enactment of the implicit power motive and initial findings within student samples verify this assumption. In the present study, we verified the role of action orientation as an antecedent for prosocial power enactment in a leadership sample (N = 383). Additionally, we found that leaders personally benefited from a prosocial enactment strategy. Results show that action orientation through prosocial power motivation leads to reduced power-related anxiety and, in turn, to greater leader well-being. The integration of motivation and self-regulation research reveals why leaders enact their power motive in a certain way and helps to understand how to establish a win-win situation for both followers and leaders.
A lack of ability to inhibit prepotent responses, or more generally a lack of impulse control, is associated with several disorders such as attention-deficit/hyperactivity disorder and schizophrenia as well as general damage to the prefrontal cortex. A stop-signal task (SST) is a reliable and established measure of response inhibition. However, using the SST as an objective assessment in diagnostic or research-focused settings places significant stress on participants as the task itself requires concentration and cognitive effort and is not particularly engaging. This can lead to decreased motivation to follow task instructions and poor data quality, which can affect assessment efficacy and might increase drop-out rates. Gamification—the application of game-based elements in nongame settings—has shown to improve engaged attention to a cognitive task, thus increasing participant motivation and data quality.
During pregnancy every eighth woman is treated with glucocorticoids. Glucocorticoids inhibit cell division but are assumed to accelerate the differentiation of cells. In this review animal models for the development of the human fetal and neonatal hypothalamic-pituitary-adrenal (HPA) axis are investigated. It is possible to show that during pregnancy in humans, as in most of the here-investigated animal models, a stress hyporesponsive period (SHRP) is present. In this period, the fetus is facing reduced glucocorticoid concentrations, by low or absent fetal glucocorticoid synthesis and by reduced exposure to maternal glucocorticoids. During that phase, sensitive maturational processes in the brain are assumed, which could be inhibited by high glucocorticoid concentrations. In the SHRP, species-specific maximal brain growth spurt and neurogenesis of the somatosensory cortex take place. The latter is critical for the development of social and communication skills and the secure attachment of mother and child. Glucocorticoid treatment during pregnancy needs to be further investigated especially during this vulnerable SHRP. The hypothalamus and the pituitary stimulate the adrenal glucocorticoid production. On the other hand, glucocorticoids can inhibit the synthesis of corticotropin-releasing hormone (CRH) in the hypothalamus and of adrenocorticotropic hormone (ACTH) in the pituitary. Alterations in this negative feedback are assumed among others in the development of fibromyalgia, diabetes and factors of the metabolic syndrome. In this work it is shown that the fetal cortisol surge at the end of gestation is at least partially due to reduced glucocorticoid negative feedback. It is also assumed that androgens are involved in the control of fetal glucocorticoid synthesis. Glucocorticoids seem to prevent masculinization of the female fetus by androgens during the sexual gonadal development. In this work a negative interaction of glucocorticoids and androgens is detectable.
Many people are aware of the negative consequences of plastic use on the environment. Nevertheless, they use plastic due to its functionality. In the present paper, we hypothesized that this leads to the experience of ambivalence—the simultaneous existence of positive and negative evaluations of plastic. In two studies, we found that participants showed greater ambivalence toward plastic packed food than unpacked food. Moreover, they rated plastic packed food less favorably than unpacked food in response evaluations. In Study 2, we tested whether one-sided (only positive vs. only negative) information interventions could effectively influence ambivalence. Results showed that ambivalence is resistant to (social) influence. Directions for future research were discussed.
Evaluative conditioning (EC) refers to changes in liking that are due to the pairing of stimuli, and is one of the effects studied in order to understand the processes of attitude formation. Initially, EC had been conceived of as driven by processes that are unique to the formation of attitudes, and that occur independent of whether or not individuals engage in conscious and effortful propositional processes. However, propositional processes have gained considerable popularity as an explanatory concept for the boundary conditions observed in EC studies, with some authors going as far as to suggest that the evidence implies that EC is driven primarily by propositional processes. In this monograph I present research which questions the validity of this claim, and I discuss theoretical challenges and avenues for future EC research.
There is ample evidence that the personality trait of extraversion is associated with frequent experiences of positive affect whereas introversion is associated with less frequent experiences of positive affect. According to a theory of Watson et al. (1997), these findings demonstrate that positive affect forms the conceptual core of extraversion. In contrast, several other researchers consider sociability - and not positive affect - as the core of extraversion. The aim of the present work is to examine the relation between extraversion and dispositional positive affect on the neurobiological level. In 38 participants resting cerebral blood flow was measured with continuous arterial spin labeling (CASL). Each participant was scanned on two measurement occasions separated by seven weeks. In addition, questionnaire measures of extraversion and dispositional positive affect were collected. To employ CASL for investigating the biological basis of personality traits, the psychometric properties of CASL blood flow measurements were examined in two studies. The first study was conducted to validate the CASL technique. Using a visual stimulation paradigm, the expected pattern of activity was found, i.e. there were specific differences in blood flow in the primary and secondary visual areas. Moreover, the results in the first measurement occasion could be reproduced in the second. Thus, these results suggest that CASL blood flow measurements have a high degree of validity. The aim of the second psychometric study was to examine whether resting blood flow measurements are characterized by a sufficient trait stability to be used as a marker for personality traits. Employing the latent state-trait theory developed by Steyer and colleagues, it was shown that about 70 % of the variance of regional blood flow could be explained by individual differences in a latent trait. This suggests that blood flow measurements have sufficient trait stability for investigating the biological basis of personality traits. In the third study, the relation between extraversion and dispositional positive affect was investigated on the neurobiological level. Voxel-based analyses showed that dispositional positive affect was correlated with resting blood flow in the ventral striatum, i.e. a brain structure that is associated with approach behavior and reward processing. This biological basis was also found for extraversion. In addition, when extraversion was statistically controlled, the association between dispositional positive affect and blood flow in the ventral striatum was still present. However, when dispositional positive affect was statistically controlled, the relation between extraversion and the ventral striatum disappeared. Taken together, these results suggest that positive affect forms a core of extraversion on the neurobiological level. The present findings thus add psychophysiological evidence to the theory of Watson et al. (1997), which suggests that positive affect forms the conceptual core of extraversion.
Fibromyalgia is a disorder of unknown etiology characterized by widespread, chronic musculoskeletal pain of at least three month duration and pressure hyperalgesia at specific tender points on clinical examination. The disorder is accompanied by a multitude of additional symptoms such as fatigue, sleep disturbances, morning stiffness, depression, and anxiety. In terms of biological disturbances, low cortisol concentrations have been repeatedly observed in blood and urine samples of fibromyalgia patients, both under basal and stress-induced conditions. The aim of this dissertation was to investigate the presence of low cortisol concentrations (hypocortisolism) and potential accompanying alterations on sympathetic and immunological levels in female fibromyalgia patients. Beside the expected hypocortisolism, a higher norepinephrine secretion and lower natural killer cell levels were found in the patient group compared to a control group consisting of healthy, age-matched women. In addition, an increased activity of some pro-inflammatory markers was observed thus leading to alterations in the balance of pro-/anti-inflammatory activity. The results underline the relevance of simultaneous investigations of interacting bodily systems for a better understanding of underlying biological mechanisms in stress-related disorders.
The efficacy and effectiveness of psychotherapeutic interventions have been proven time and again. We therefore know that, in general, evidence-based treatments work for the average patient. However, it has also repeatedly been shown that some patients do not profit from or even deteriorate during treatment. Patient-focused psychotherapy research takes these differences between patients into account by focusing on the individual patient. The aim of this research approach is to analyze individual treatment courses in order to evaluate when and under which circumstances a generally effective treatment works for an individual patient. The goal is to identify evidence based clinical decision rules for the adaptation of treatment to prevent treatment failure. Patient-focused research has illustrated how different intake indicators and early change patterns predict the individual course of treatment, but they leave a lot of variance unexplained. The thesis at hand analyzed whether Ecological Momentary Assessment (EMA) strategies could be integrated into patient-focused psychotherapy research in order to improve treatment response prediction models. EMA is an electronically supported diary approach, in which multiple real-time assessments are conducted in participants" everyday lives. We applied EMA over a two-week period before treatment onset in a mixed sample of patients seeking outpatient treatment. The four daily measurements in the patients" everyday environment focused on assessing momentary affect and levels of rumination, perceived self-efficacy, social support and positive or negative life events since the previous assessment. The aim of this thesis project was threefold: First, to test the feasibility of EMA in a routine care outpatient setting. Second, to analyze the interrelation of different psychological processes within patients" everyday lives. Third and last, to test whether individual indicators of psychological processes during everyday life, which were assessed before treatment onset, could be used to improve prediction models of early treatment response. Results from Study I indicate good feasibility of EMA application during the waiting period for outpatient treatment. High average compliance rates over the entire assessment period and low average burdens perceived by the patients support good applicability. Technical challenges and the results of in-depth missing analyses are reported to guide future EMA applications in outpatient settings. Results from Study II shed further light on the rumination-affect link. We replicated results from earlier studies, which identified a negative association between state rumination and affect on a within-person level and additionally showed a) that this finding holds for the majority but not every individual in a diverse patient sample with mixed Axis-I disorders, b) that rumination is linked to negative but also to positive affect and c) that dispositional rumination significantly affects the state rumination-affect association. The results provide exploratory evidence that rumination might be considered a transdiagnostic mechanism of psychological functioning and well-being. Results from Study III finally suggest that the integration of indicators derived from EMA applications before treatment onset can improve prediction models of early treatment response. Positive-negative affect ratios as well as fluctuations in negative affect measured during patients" daily lives allow the prediction of early treatment response. Our results indicate that the combination of commonly applied intake predictors and EMA indicators of individual patients" daily experiences can improve treatment response predictions models. We therefore conclude that EMA can successfully be integrated into patient-focused research approaches in routine care settings to ameliorate or optimize individual care.
The midcingulate cortex has become the focus of scientific interest as it has been associated with a wide range of attentional phenomena. This survey found evidence indicating the relevance of gender and handedness for measures of regional cortical morphology. Although gender was associated with structural variations concerning the neuroanatomy of the midcingulum bundle as well, handedness did not emerge in the analyses of white matter characteristics as significant factor. Hemispheric differences were found at the level of both gray and white matter. Turning to the functional implications of neuroanatomical variations and comparing subjects with a pronounced and a low degree of midcingulate folding, which indicates differential expansions of cytoarchitectural areas, behavioral and electrophysiological differences in the processing of interference became evident. A high degree of leftward midcingulate fissurization was associated with better behavioral performance, presumably caused by a more effective conflict-monitoring system triggering fast and automatic attentional filtering mechanisms. Subjects exhibiting a lower degree of midcingulate fissurization rather seem to rely on more effortful control processes. These results carry implications not only concerning neuronal representations of individual differences in attentional processes, but might also be of relevance for the refinement of models for mental disorders.
Phase-amplitude cross-frequency coupling is a mechanism thought to facilitate communication between neuronal ensembles. The mechanism could underlie the implementation of complex cognitive processes, like executive functions, in the brain. This thesis contributes to answering the question, whether phase-amplitude cross-frequency coupling - assessed via electroencephalography (EEG) - is a mechanism by which executive functioning is implemented in the brain and whether an assumed performance effect of stress on executive functioning is reflected in phase-amplitude coupling strength. A huge body of studies shows that stress can influence executive functioning, in essence having detrimental effects. In two independent studies, each being comprised of two core executive function tasks (flexibility and behavioural inhibition as well as cognitive inhibition and working memory), beta-gamma phase-amplitude coupling was robustly detected in the left and right prefrontal hemispheres. No systematic pattern of coupling strength modulation by either task demands or acute stress was detected. Beta-gamma coupling might also be present in more basic attention processes. This is the first investigation of the relationship between stress, executive functions and phase-amplitude coupling. Therefore, many aspects have not been explored yet. For example, studying phase precision instead of coupling strength as an indicator for phase-amplitude coupling modulations. Furthermore, data was analysed in source space (independent component analysis); comparability to sensor space has still to be determined. These as well as other aspects should be investigated, due to the promising finding of very robust and strong beta-gamma coupling for all executive functions. Additionally, this thesis tested the performance of two widely used phase-amplitude coupling measures (mean vector length and modulation index). Both measures are specific and sensitive to coupling strength and coupling width. The simulation study also drew attention to several confounding factors, which influence phase-amplitude coupling measures (e. g. data length, multimodality).
Stress related disorders increase continuously. It is not yet clear if stress also promotes breast cancer. This dissertation provides an analyses of the current state of research and focuses on the significance of pre-/postnatal stress factors and chronic stress. The derived hypotheses are empirically examined on breast cancer patients. The clinical study investigates the links between those factors and prognosis and outcome.
The present study examined associations between fathers’ masculinity orientation and their anticipated reaction toward their child’s coming out as lesbian or gay (LG). Participants were 134 German fathers (28 to 60years) of a minor child. They were asked how they would personally react if, one day, their child disclosed their LG identity to them. As hypothesized, fathers with a stronger masculinity orientation (i.e., adherence to traditional male gender norms, such as independence, assertiveness, and physical strength) reported that they would be more likely to reject their LG child. This association was serially mediated by two factors: fathers’ general anti-LG attitudes (i.e., level of homophobia) and their emotional distress due to their child’s coming out (e.g., feelings of anger, shame, or sadness). The result pattern was independent of the child’s gender or age. The discussion centers on the problematic role of traditional masculinity when it comes to fathers’ acceptance of their non-heterosexual child.
This intervention study explored the effects of a newly developed intergenerational encounter program on cross-generational age stereotyping (CGAS). Based on a biographical-narrative approach, participants (secondary school students and nursing home residents) were invited to share ideas about existential questions of life (e.g., about one’s core experiences, future plans, and personal values). Therefore, the dyadic Life Story Interview (LSI) had been translated into a group format (the Life Story Encounter Program, LSEP), consisting of 10 90-min sessions. Analyses verified that LSEP participants of both generations showed more favorable CGAS immediately after, but also 3 months after the program end. Such change in CGAS was absent in a control group (no LSEP participation). The LSEP-driven short- and long-term effects on CGAS could be partially explained by two program benefits, the feeling of comfort with and the experience of learning from the other generation.
The contribution of three genes (C15orf53, OXTR and MLC1) to the etiology of chromosome 15-bound schizophrenia (SCZD10), bipolar disorder (BD) and autism spectrum disorder (ASD) were studied. At first, the uncharacterized gene C15orf53 was comprehensively analyzed. Previous genome-wide association studies (GWAS) in bipolar disorder samples have identified an association signal in close vicinity to C15orf53 on chromosome 15q14. This gene is located in exactly the genomic region, which is segregating in our SCZD10 families. An association study with bipolar disorder (BD) and SCZD10 individual samples did not reveal any association of single nucleotide polymorphisms (SNPs) in C15orf53. Mutational analysis of C15orf53 in SCZD10-affected individuals from seven multiplex families did not show any mutations in the 5'-untranslated region, the coding region and the intron-exon boundaries. Gene expression analysis revealed that C15orf53 was expressed in a subpopulation of leukocytes, but not in human post-mortem limbic brain tissue. Summarizing these studies, C15orf53 is unlikely to be a strong candidate gene for the etiology of BD or SCZD10. The second investigated gene was the human oxytocin receptor gene (OXTR). Five well described SNPs located in the OXTR gene were taken for a transmission-disequilibrium test (TDT) in parents-child trios with ASD-affected children. Neither in the complete sample nor in a subgroup with children that had an intelligence quotient (IQ) above 70, association was found, independent from the application of Haploview or UNPHASED for analysis. The third gene, MLC1, was investigated with regards to its implication in the etiology of SCZD10. Mutations in the MLC1 gene lead to megalencephalic leukoencephalopathy with subcortical cysts (MLC) and one variant coding for the amino acid methionine (Met) instead of leucine (Leu) at position 309 was identified to segregate in a family affected with SCZD10. For further investigation of MLC1 and its possible implication in the etiology of SCZD10, a constitutive Mlc1 knockout mouse model should be created. Mouse embryonic stem cells (mES) were electroporated with a knockout vector construct and analyzed with respect to homologous recombination of the knockout construct with the genomic DNA (gDNA) of the mES. Polymerase chain reaction (PCR) on the available stem cell clones did not reveal any homologous recombined ES. Additionally, we conducted experiments to knockdown MLC1 and using microRNAs. The 3'-untranslated region of the MLC1 gene was analyzed with the bioinformatics tool TargetScan to screen for potential microRNA target sites. In the 3'-untranslated region of the MLC1 gene, a potential binding site for miR-137 was identified. The gene expression level of genes that had been linked to psychiatric disorders and carried a predicated miR-137 binding site has been proven to be immediately responsive to miR-137. Thus, there is new evidence that MLC1 is a candidate gene for the etiology of SCZD10.
Stress and pain are common experiences in human lives. Both, the stress and the pain system have adaptive functions and try to protect the organism in case of harm and danger. However, stress and pain are two of the most challenging problems for the society and the health system. Chronic stress, as often seen in modern societies, has much impact on health and can lead to chronic stress disorders. These disorders also include a number of chronic pain syndromes. However, pain can also be regarded as a stressor itself, especially when we consider how much patients suffer from long-lasting pain and the impact of pain on life quality. In this way, the effects of stress on pain can be fostered. For the generation and manifestation of chronic pain symptoms also learning processes such as classical conditioning play an important role. Processes of classical conditioning can also be influenced by stress. These facts illustrate the complex and various interactions between the pain and the stress systems. Both systems communicate permanently with each other and help to protect the organism and to keep a homeostatic state. They have various ways of communication, for example mechanisms related to endogenous opioids, immune parameters, glucocorticoids and baroreflexes. But an overactivation of the systems, for example caused by ongoing stress, can lead to severe health problems. Therefore, it is of great importance to understand these interactions and their underlying mechanisms. The present work deals with the relationship of stress and pain. A special focus is put on stress related hypocortisolism and pain processing, stress induced hypoalgesia via baroreceptor related mechanisms and stress related cortisol effects on aversive conditioning (as a model of pain learning). This work is a contribution to the wide field of research that tries to understand the complex interactions of stress and pain. To demonstrate the variety, the selected studies highlight different aspects of these interactions. In the first chapter I will give a short introduction on the pain and the stress systems and their ways of interaction. Furthermore, I will give a short summary of the studies presented in Chapter II to V and their background. The results and their meaning for future research will be discussed in the last part of the first chapter. Chronic pain syndromes have been associated with chronic stress and alterations of the HPA axis resulting in chronic hypocortisolism. But if these alterations may play a causal role in the pathophysiology of chronic pain remains unclear. Thus, the study described in Chapter II investigated the effects of pharmacological induced hypocortisolism on pain perception. Both, the stress and the pain system are related to the cardiovascular system. Increase of blood pressure is part of the stress reaction and leads to reduced pain perception. Therefore, it is important for the usage of pain tests to keep in mind potential interferences from activation of the cardiovascular system, especially when pain inhibitory processes are investigated. For this reason we compared two commonly and interchangeably used pain tests with regard to the triggered autonomic reactions. This study is described in chapter III. Chapter IV and V deal with the role of learning processes in pain and related influences of stress. Processes of classical conditioning play an important role for symptom generation and manifestation. In both studies aversive eyeblink conditioning was used as a model for pain learning. In the study described in Chapter IV we compared classical eyeblink conditioning in healthy volunteers to patients suffering from fibromyalgia, a chronic pain disorder. Also, differences of the HPA axis, as part of the stress system, were taken in account. The study of Chapter V investigated effects of the very first stress reaction, particularly rapid non-genomic cortisol effects. Healthy volunteers received an intravenous cortisol administration immediately before the eyeblink conditioning. Rapid effects have only been demonstrated on a cellular level and on animal behavior so far. In general, the studies presented in this work may give an impression of the broad variety of possible interactions between the pain and the stress system. Furthermore, they contribute to our knowledge about theses interactions. However, more research is needed to complete the picture.
One mechanism underlying the acquisition of interpersonal attitudes is the formation of an association between a valenced unconditioned stimulus (US) and an affectively neutral conditioned stimulus (CS). However, a stimulus (e.g., a person) is not always and necessarily perceived to be unambiguously positive or negative. An individual can be negative regarding abstract (trait) information but at the same time display a positive (concrete) behavior. The present research deals with the question of whether the valence of abstract or concrete information about a US is encoded and subsequently transferred to an associated CS. The central assumptions are that the valence of the concrete information is more important for the evaluation of the US, whereas the abstract information is more important for the evaluation of the CS. The rationale behind these assumptions is that the US is a psychologically proximal stimulus because it elicits a more direct affective reaction. The CS, however, is psychologically more distal because it is merely associated with the US and is therefore only experienced indirectly. It is postulated that the associative relation between US and CS constitutes a dimension of psychological distance. In four studies, the valence of abstract and concrete information about a number of USs was manipulated. Within an evaluative learning paradigm, these stimuli were associated with affectively neutral CSs. As predicted, ambivalent USs were evaluated according to the valence of the concrete information. The evaluation of CSs, however, was influenced more strongly by the valence of the abstract information. Moreover, in a subsequent lexical decision task, participants were faster to categorize abstract (vs. concrete) stimuli when the stimuli were preceded by a CS prime as compared to a US prime. The results provide first evidence that perceived psychological distance influences the evaluations of US and CS in an associative evaluative learning paradigm.
The last decades of stress research have yielded substantial advancements highlighting the importance of the phenomenon for basic psychological functions as well as physical health and well-being. Progress in stress research heavily relies on the availability of suitable and well validated laboratory stressors. Appropriate laboratory stressors need to be able to reliably provoke a response in the relevant parameters and be applicable in different research settings or experimental designs. This thesis focuses on the Cold Pressor Test (CPT) as a stress induction technique. Three published experiments are presented that show how the advantages of the CPT can be used to test stress effects on memory processes and how some of its disadvantages can be met by a simple modification that retains its feasibility and validity. The first experiment applies the CPT in a substantial sample to investigate the consolidation effects of post-learning sympathetic arousal. Stressed participants with high increases in heart rate during the CPT showed enhanced memory performance one day after learning compared to both the warm water control group and low heart rate responders. This finding suggests that beta-adrenergic activation elicited shortly after learning enhances memory consolidation and that the CPT induced heart rate response is a predictor for this effect. Moreover, the CPT proved to be an appropriate stressor to test hypothesis about endogenous adrenergic effects on memory processes. The second experiment addresses known practical limitations of the standard dominant hand CPT protocol. A bilateral feet CPT modification is presented, the elicited neuroendocrine stress response assessed and validated against the standard CPT in a within-subjects design. The bilateral feet CPT elicited a substantial neuroendocrine stress response. Moreover, with the exception of blood pressure responses, all stress parameters were enhanced compared to the standard CPT. This shows that the bilateral feet CPT is a valid alternative to the standard CPT. The third experiment further validates the bilateral feet CPT and its corresponding control procedure by employing it in a typical application scenario. Specifically, the bilateral feet CPT was used to modulate retrieval of event files in a distractor-response binding paradigm that required lateralized bimanual responses. Again, the bilateral feet CPT induced significant increases in heart rate, blood pressure and cortisol, no such increases could be observed in the warm water control condition. Moreover, stressed participants showed diminished retrieval compared to controls. These results provide further evidence for the feasibility and validity of the bilateral feet CPT and its warm water control procedure. Together the experiments presented here highlight the usefulness of the CPT as a tool in psychophysiological stress research. It is especially well suited to test hypothesis concerning stress effects on memory processes and its applicability can be further increased by the bilateral feet modification.
Stress is a common phenomenon for animals living in the wild, but also for humans in modern societies. Originally, the body's stress response is an adaptive reaction to a possibly life-threatening situation, and it has been shown to impact on energy distribution and metabolism, thereby increasing the chance of survival. However, stress has also been shown to impact on mating behaviour and reproductive strategies in animals and humans. This work deals with the effect of stress on reproductive behavior. Up to now, research has only focused on the effects of stress on reproduction in general. The effects of stress on reproduction may be looked at from two points of view. First, stress affects reproductive functioning by endocrine (e.g. glucocorticoid) actions on the reproductive system. However, stress can also influence reproductive behavior, i.e. mate choice and mating preferences. Animals and humans do not mate randomly, but exhibit preferences towards mating partners. One factor by which animals and humans choose their mating partners is similarity vs. dissimilarity: Similar mates usually carry more of one's own genes and the cooperation between similar mates is, at least theoretically, less hampered by expressing diverse behaviors. By mating with dissimilar mates on the other hand one may acquire new qualities for oneself, but also for one's offspring, useful to cope with environmental challenge. In humans we usually find a preference for similar mates. Due to the high costs of breeding, variables like cooperation and life-long partnerships may play a greater role than the acquaintance of new qualities.The present work focuses on stress effects on mating preferences of humans and will give a first answer to the question whether stress may affect our preference for similar mates. Stress and mating preferences are at the centre of this work. Thus, in the first Chapter I will give an introduction on stress and mating preferences and link these topics to each other. Furthermore, I will give a short summary of the studies described in Chapter II - Chapter IV and close the chapter with a general discussion of the findings and directions for further research on stress and mating preferences. Human mating behavior is complex, and many aspects of it may not relate to biology but social conventions and education. This work will not focus on those aspects but rather on cognitive and affective processing of erotic and sexually-relevant stimuli, since we assume that these aspects of mating behaviour are likely related to psychobiological stress mechanisms. Therefore, a paradigm is needed that measures such aspects of mating preferences in humans. The studies presented in Chapter II and Chapter III were performed in order to develop such a paradigm. In these studies we show that affective startle modulation may be used to indicate differences in sexual approach motivation to potential mating partners with different similarity levels to the participant. In Chapter IV, I will describe a study that aimed to investigate the effects of stress on human mating preferences. We showed that stress reverses human mating preferences: While unstressed individuals show a preference for similar mates, stressed individuals seem to prefer dissimilar mates. Overall, the studies presented in this work showed that affective startle modulation can be employed to measure mating preferences in humans and that these mating preferences are influenced by stress.