In this thesis four studies assessing putative pathways implicated in cognitive models of depression are presented and discussed. In two initial studies the possibility to manipulate attention... Show moreIn this thesis four studies assessing putative pathways implicated in cognitive models of depression are presented and discussed. In two initial studies the possibility to manipulate attention allocation bias using two types of attention bias modification (ABM) procedures was explored. Neither method successfully or consistently modified attention allocation bias in dysphoric individuals. Putative interactions between 5-HTTLPR genotype and life stress were studied in the third study. Adopting an endophenotype approach, effects on measures of biased information processing were assessed. S-allele carriers showed increased recognition of negative mood state as a function of recent negative life events. Hypothesized interactions with childhood emotional abuse or affection attention allocation bias were found non-significant. A main effect of 5-HTTLPR was observed such that s- allele carriers selectively oriented attention towards negative information. In the fourth study the predictive value of cognitive reactivity to sad mood (measured with the LEIDS-r questionnaire) for the first onset of depression was assessed. Among 834 never previously depressed participants, cognitive reactivity predicted first onset of depression over the subsequent two years, even when various other factors, including baseline symptoms and negative life events, were statistically controlled for. Finally, these findings are discussed and related to the existing literature Show less
This thesis addressed the physiological impact of fear in 4- and 7-year-old children, induced by media and social fear-inducing tasks (the Trier Social Stress Test for Children). The main question... Show moreThis thesis addressed the physiological impact of fear in 4- and 7-year-old children, induced by media and social fear-inducing tasks (the Trier Social Stress Test for Children). The main question pertained to individual differences in physiological reactivity to fear-inducing stimuli. The possibly relevant factors of attachment security, the child’s temperamental fearfulness, and variations in the serotonin transporter gene (5-HTTLPR; long vs. short allele) were taken into account. Results showed that temperament, attachment, and genetic influences play significant and interactive roles in the expression of fear reactivity. A secure relationship affected the reactivity to media-induced fear stimuli in temperamentally more fearful children but not in less fearful children irrespective of children’s ages. This finding adds to the growing literature showing that children high in negative emotion are more susceptible to positive as well as negative rearing influences. Furthermore, we found evidence that reactivity to the social fear-inducing task was explained by a combination of variations in the serotonin transporter gene and attachment security. Children with a secure attachment representation and two long 5-HTT alleles showed the lowest levels of fear reactivity, indicating that physiological reactivity to a social fear-inducing task is a product of the child’s biology and environment. Show less