In this thesis, in order to shed light on the biological function of the membrane-bound Glucocorticoid Receptor (mGR), proteomic changes induced by 15 min in vivo acute stress and by short in vitro activation of the mGR were analyzed in T-lymphocytes. The numerous overlaps between the two datasets suggest that the mGR mediates physiologically relevant actions and participates in the early stress response, triggering rapid early priming events that pave the way for the slower genomic GC activities. In addition, a new commercially available method with suitable sensitivity to detect the human mGR is reported and the transcriptional origin of this protein investigated. Our results indicates that specific GR-transcripts, containing exon 1C and 1D, are associated with the expression of this membrane isoform.
Zurzeit werden gesundheitliche Auswirkungen von Mobilfunkstrahlung auf den Menschen kontroversiell diskutiert. Die vorliegende Arbeit untersuchte mögliche Auswirkungen auf Befindlichkeit und psychische Variablen in zwei Studien. Es zeigte sich ein Trend bei einer Variable, es gab jedoch keine signifikanten Effekte. Bei den nicht-experimentellen Befunden wiesen Anrainer von Mobilfunksendeanlagen (self-rater) höhere psychische Belastung auf.
Changes in the cardiovascular system are an often described state in eating disorders. Women with anorexia and bulimia nervosa and control persons were studied before and after a treatment in a psychosomatic clinic. Using different methods cardiovascular reactivity was evaluated in rest and during mental stress and exercise. Improvements after treatment were defined by weight gain, an increase of the trijodthyroninlevel and no more purging in the last three weeks. The anorectics showed higher epinephrinlevels than the other women. The cardiovascular parameters demonstrated an increase of parasympathic activity and a decrease of sympathetic activity in eating disorders. However, the reactivities on stressors showed no differences in comparison to the control group. No changes were observed during the treatment apart from the heartrate, which showed a tendency to increase in the last week of therapy. Because the improvements during the therapy were generally small, within the present study it could not be clarified wether the observed alterations are reversible. An increase of the parasympathic activity in autonome regulation of the heart in eating disorders has been demonstrated and the reactivity on stressors appears to be normal.
The startle response in psychophysiological research: modulating effects of contextual parameters
(2013)
Startle reactions are fast, reflexive, and defensive responses which protect the body from injury in the face of imminent danger. The underlying reflex is basic and can be found in many species. Even though it consists of only a few synapses located in the brain stem, the startle reflex offers a valuable research method for human affective, cognitive, and psychological research. This is because of moderating effects of higher mental processes such as attention and emotion on the response magnitude: affective foreground stimulation and directed attention are validated paradigms in startle-related research. This work presents findings from three independent research studies that deal with (1) the application of the established "affective modulation of startle"-paradigm to the novel setting of attractiveness and human mating preferences, (2) the question of how different components of the startle response are affected by a physiological stressor and (3) how startle stimuli affect visual attention towards emotional stimuli. While the first two studies treat the startle response as a dependent variable by measuring its response magnitude, the third study uses startle stimuli as an experimental manipulation and investigates its potential effects on a behavioural measure. The first chapter of this thesis describes the basic mechanisms of the startle response as well as the body of research that sets the foundation of startle research in psychophysiology. It provides the rationale for the presented studies, and offers a short summary of the obtained results. Chapter two to four represent primary research articles that are published or in press. At the beginning of each chapter the contribution of all authors is explained. The references for all chapters are listed at the end of this thesis. The overall scope of this thesis is to show how the human startle response is modulated by a variety of factors, such as the attractiveness of a potential mating partner or the exposure to a stressor. In conclusion, the magnitude of the startle response can serve as a measure for such psychological states and processes. Beyond the involuntary, physiological startle reflex, startle stimuli also affect intentional behavioural responses, which we could demonstrate for eye movements in a visual attention paradigm.