Sökning: "acoustic startle response"
Visar resultat 1 - 5 av 8 avhandlingar innehållade orden acoustic startle response.
1. Fear, Startle, and Fear-Potentiated Startle : Probing Emotion in the Human Brain
Sammanfattning : The present thesis explored the neurobiological basis of three aspects of defense behaviors in humans. Positron emission tomography methodology was used, and changes in regional cerebral blood flow (rCBF) were measured as an index of neural activity. LÄS MER
2. The Effect of Steroid Hormones in the Female Brain During Different Reproductive States
Sammanfattning : Women are twice as likely as men to suffer from depression and anxiety disorders and have an increased risk of onset during periods associated with hormonal changes, such as the postpartum period and the menopausal transition. Furthermore, some women seem more sensitive to normal hormone fluctuations across the menstrual cycle, since approximately 3-5% suffers from premenstrual dysphoric disorder (PMDD). LÄS MER
3. Physiological Stress Reactivity in Late Pregnancy
Sammanfattning : During pregnancy, the basal activity is increased in both of our major stress response systems: the sympathetic nervous system and the hypothalamic-pituitary-adrenal axis. At the same time, the reactivity towards stressors is reduced. These alterations sustain maternal and fetal homeostasis, and are involved in the regulation of gestational length. LÄS MER
4. Schizophrenia and Nitric Oxide: Deficits in Information Processing Invetigated in Animal Models
Sammanfattning : Rationale: Schizophrenia-like symptoms can be induced in humans by phencyclidine (PCP), a non-competitive antagonist of the N-methyl-D-aspartate (NMDA) receptor. Schizophrenic patients and PCP-treated animals display deficits in pre-attentive information processing, as assessed by e.g. prepulse inhibition of the acoustic startle response. LÄS MER
5. Hormones, Mood and Cognition
Sammanfattning : Ovarian steroid hormones are neuroactive steroids with widespread actions in the brain, and are thus able to influence mood, behavior and cognition. In this thesis the effects of progesterone withdrawal and the direct effects of the progesterone metabolite allopregnanolone are evaluated. LÄS MER