Placebos have been shown to affect both subjective experiences and physiological markers. However, their influence on defensive responses to threat has yet to be investigated. This study examines...Show morePlacebos have been shown to affect both subjective experiences and physiological markers. However, their influence on defensive responses to threat has yet to be investigated. This study examines whether a placebo manipulation can impact subjective pain ratings in response to the shock, as well as heart rate during shock anticipation, in healthy individuals. Participants (n=72) were tested in a Pavlovian threat conditioning paradigm over two days with a 24-hour interval, in a within-subject design. A sham analgesic electrical stimulation (TENS) was used to induce a placebo effect. The placebo conditioning process paired a placebo stimulus ("painful shock + TENS") with a low pain response, followed by two sessions of associative threat conditioning. Subjective pain ratings and heart rate, as an indicator of the freezing response, were measured across different conditions. The STAI-trait questionnaire was also completed. Results indicated higher subjective pain levels in response to the painful shock compared to the TENS shock during the threat acquisition phase. Importantly, during this phase, stronger heart rate deceleration, indicative of freezing, was observed when anticipating the painful shock versus the TENS shock. There was no evidence the placebo effect persisted during the threat retention stage, as there were no significant differences in heart rate while anticipating the two conditions. Trait anxiety did not significantly influence the placebo response. These findings demonstrate that a placebo intervention affects not only subjective experiences but also physiological responses to threat, highlighting the potential of using placebos as co-interventions for individuals experiencing anxiety.Show less
Worry and anxiety are associated with an increase in absolute heart rate, while heart rate variability decreases. Low heart rate variability is associated with an active anterior insula. A...Show moreWorry and anxiety are associated with an increase in absolute heart rate, while heart rate variability decreases. Low heart rate variability is associated with an active anterior insula. A hyperactive anterior insula is observed in individuals with anxiety disorders. However, it is not yet known whether a hyperactive anterior insula makes a person vulnerable to developing anxiety disorders or whether the anterior insula becomes hyperactive as a result of the disorder. Therefore, this study aims to investigate these associations in healthy participants. The following research questions were asked, "Is there a correlation between absolute heart rate and trait worry?" and "Is trait worry associated with low heart rate variability?" the same questions are posed in the context of anxiety. Finally, the question "Is trait anxiety associated with a hyperactive insula?" is asked. To examine this, data from the HADS, PSWQ, vectorcardiogram measures of heart rate and the heart rate variability, and the functional connectivity of the salience network from the 30 female participants were used. Results show no significant relationship between absolute heart rate, heart rate variability, and trait worry and anxiety in healthy participants. A significant relationship between the functional connectivity in the anterior insula and trait anxiety was found in our sample (r = .42, p = <.05). The effects of worry and anxiety on cardiac activity are mainly seen in clinically diagnosed individuals under an unpredictable and uncontrollable stressful environment. Our sample were healthy individuals, so symptoms were apparently not severe enough. The effects of trait anxiety are directly reflected in brain connectivity in the anterior insula observed in our analysis. The results can be applied to treatments reducing anxiety and worry.Show less
Research master thesis | Developmental Psychopathology in Education and Child Studies (research) (MSc)
open access
2019-07-19T00:00:00Z
Objective. To examine the effect of the parenting style of the mother on the relation between maternal depression and the infant’s stress response system. Method. The sample consisted of 55 mothers...Show moreObjective. To examine the effect of the parenting style of the mother on the relation between maternal depression and the infant’s stress response system. Method. The sample consisted of 55 mothers and their infants. Maternal depressive symptoms were assessed during pregnancy and when the infant was six months old, by means of the Beck Depression Inventory-II. Maternal parenting style was observed from mother-infant interaction during the Still Face Paradigm, when the infant was six months old. When the infant was 12 months old, a stress-paradigm was conducted during which both physiological and behavioral measures of infant stress reactivity were obtained. Results. Maternal postnatal depressive symptoms were found to be negatively related to maternal sensitivity. In addition, maternal prenatal as well as postnatal depressive symptoms were found to predict infant baseline heart rate, infant stress reactivity and infant heart rate recovery, but only in interaction with certain characteristics of the mother’s parenting style. Conclusions. The present study underlines that the way a mother interacts with her child is very important for the development of the child’s neurobiological system and that her parenting style can either buffer or enhance the effect of maternal psychopathology. Teaching mothers at risk how to interact positively and adequately with their child and how to respond to its needs, could possibly decrease the deleterious effects of maternal depression on child development.Show less
