|
|
Biological and related theories of aggression and its humoral regulation
Bradáč, Ondřej ; Komárek, Stanislav (advisor) ; Havlíček, Jan (referee)
Aggression is a phenomenon which acquired a substantial share on attention of biological literature, especially since the beginning of 20th century. In this thesis, various approaches to the problem from the field of biology are summarized. Intensified attention is dedicated to the theoretical concepts of aggression, especially the concepts consulting the problem of aggression from the evolutionary point of view and to the research on the field of hormonal regulation of aggression, stressing out the role of the hormone testosterone, and to particular hypothesis, which take account on its mutual relationship with behavior. The empirical part of the thesis is dedicated to verification of premises of the challenge hypothesis according to the relationship between testosterone and aggressive behavior. Significant findings of the empirical part refer to the existence of a link between basal level of testosterone and aggressive tendencies and to the existence of a negative link between basal level of testosterone and its increase in reaction to a competitive situation.
|
|
| |
|
| |
|
| |
|
|
16-androstenes Anosmia in Men
Vondrová, Marta ; Havlíček, Jan (advisor) ; Martinec Nováková, Lenka (referee)
16-androstenes Anosmia in Men 16-androstens are compounds of steroid character which are secreted to the skin as part of apocrine glands secrets and they participate in creating body odor. It was found that androstenes influence affective state and psychophysiological reactions. The effect of androstenes can be also found on subliminal level. However, it has not yet been tested whether individuals with specific anosmia could also be influenced this way. Specific anosmia is described as an individual's incapability of conscious detection of particular odor while the detection of other compounds remains unaffected. The aim of the thesis is to test whether specifically anosmic individuals can be influenced by compounds to which they are anosmic to. This hypothesis is based on research of sensitization. Previous research indicates that olfactory perception may be of larger plasticity than thought. The theoretical part focuses on critical analysis of androstenes and research on specific anosmia. This field contains topics such as influence of chemical structure on androstenes perception, genetic influences, sensitization, functions of androstenes in interpersonal interactions and research on brain imagining. The experimental part focused on measuring subjective ratings of mood and psychophysiological...
|
|
|
Úleková reakce u osob s latentní toxoplasmosou
Příplatová, Lenka ; Flegr, Jaroslav (advisor) ; Havlíček, Jan (referee)
Possible connection between latent toxoplasmosis and schizophrenia is a very interesting and medically important topic. In this thesis I tried to map current state of knowledge in the interdisciplinary research of schizophrenia and Toxoplasma gondii and their possible connections as well as to show differences in responses between Toxoplasma-positive and Toxoplasma-negative subjects using simple computer-administered tests of prepulse inhibition of startle reaction (PPI). Such differences would suggest another similarity between schizophrenia patients and subjects with latent toxoplasmosis as the sensorimotor gating responsible for PPI was found to be disrupted in schizophrenia patients. Side goal of the study was to test newly developed PC software for testing PPI and to determine its applicability in further research. Subjects for the tests were recruited among adepts of professional military service; 409 subjects completed the test of acoustic PPI and 276 subjects completed the test of visual PPI. All the subjects were tested on presence of specific anti-Toxoplasma IgG in their blood serum. Both tests revealed significant (p<0.001) differences between responses on prepulse-preceded stimuli and plain stimuli without prepulse, no significant results were, however, gained for the effects of latent...
|
|
|
Vztah atraktivity a MHC: Role menstruačního cyklu a partnerského statusu.
Vávrová, Kateřina ; Havlíček, Jan (advisor) ; Flegr, Jaroslav (referee)
Extremely polymorphic genes of major histocompatibility complex (MHC) play a significant role in the function of immune system by recognizing heterogeneous particles, mainly pathogenic origin. Previous research on various vertebrate species indicates that MHC influences individual body odour and mate choice preferences. Many individuals tend to prefer MHC dissimilar partner so that warrants them an offspring resistant against wider spectrum of infections. Research on MHC-related mate preferences in humans, however, is inconclusive to date. Several studies indicate that women not taking hormonal contraceptives prefer the smell of MHC dissimilar partners while other studies have not come to this conclusion. This can be caused by the absence of potentially influencing factors like the menstrual cycle phase. The aim of this study was to test MHC-similarity mate choice preferences in odour, facial and vocal modalities. In particular, we focused on a potential effect of hormonal contraception. Furtermore, we tested preferential shifts across the menstrual cycle by comparing women's preferences in the follicular and the luteal phase in pill and non-pill users. A group of 52 women in different phases of their menstrual cycle rated odour samples, photos and vocal recordings taken from 51 men. All...
|
|
| |
|
|
The effect of stress on hedonic quality body odor
Piškule, Petra ; Havlíček, Jan (advisor) ; Martinec Nováková, Lenka (referee)
There are many environmental factors that influence the human body odour, one of them is emotional state. Several previous studies focused on changes in hedonic quality of human body odor, caused by emotional state. The theoretical part of this study focuses on analysis of odor individuality, environmental factors that influence human body odor and on description of current stress models. The primary objective of the empiric part of this project was to test the effect of stress on subjectively perceived axillary odour. We expected that the stress situation will decrease pleasantness and increase intensity of body odor. This hypothesis was chosen because of other similar studies that focused on the effect of stress on human body odor. The experimental part of this study consists of three experiments, in which we recorded women's ratings of men sweat samples. We found significant results in rating of intensity in the first experiment, which focused on the stress during a writing exam at the university. In the second experiment, there were found significant results in ratings of intensity and pleasantness during stressful conditions. We achieved the most innovative result and acceptance of our determine hypothesis in our last experiment. The sweat samples of fans's winning team were judged as...
|
|
|
The effect of caloric intake and aromatic substances on the human body odour quality
Fialová, Jitka ; Havlíček, Jan (advisor) ; Martinec Nováková, Lenka (referee)
Previous work has shown that mate choice is in part affected by cues associated with quality and condition of potential mate. These cues could be based on visual characteristics or as shown recently on chemical cues. There is growing evidence which suggest that body odour plays relatively significant role in mate choice. Moreover, body odour is to some extent affected by ingested diet. Therefore, we focused on the effect of caloric restriction and garlic consumption on axilary odour. Our results suggest that restoration of food intake improve body odour in terms of pleasantness and attractiveness (probably as a consequence of recommended specific diet), but during caloric restriction it is rated lower. The garlic consumption improves hedonic assessment of body odour. This effect could be ascribed to his well-known health effects. Our findings thus confirm assumption that ingested diet affects body odour and these changes in odour attractiveness could serve as a cue to individual condition and quality.
|
guest ::
RSS feed.