Background: The fetal origins hypothesis poses that adverse intrauterine conditions predispose to cardiovascular and metabolic diseases in adulthood. Evidence is accumulating that similar mechanisms to those identified for physical disorders may also apply to psychiatric disorders. Focusing on the activity of neurophysiological systems thought to regulate emotions from very early in life may be key to understanding how maternal stress in pregnancy impacts on the developing baby with possible long-lasting consequences for behaviour and psychopathology. Respiratory Sinus Arrhythmia (RSA), "vagal tone", is thought to reflect autonomic regulatory capabilities that may underpin emotion regulation. However, little is known about possible fetal origins of vagal tone. Animal studies increasingly point to sex differences in the effects of prenatal stress, and this is supported by human studies of the prenatal origins of cardiovascular functioning and psychopathology. The current investigation examines whether prenatal depression and anxiety predict vagal tone in infancy, and whether the associations are modified by infant sex. Method: Two hundred mothers and infants from a high-risk consecutive community sample were examined prospectively from the first trimester of pregnancy until 29 weeks postnatal. Maternal self-reports of stress (EPDS and STAI) were collected in pregnancy (20 and 32 weeks) and postnatally (5 weeks and 29 weeks). Vagal tone was ascertained across five procedures, the "Helper-Hinderer" social evaluation task, toy exploration and the "Still Face" paradigm (2 minutes of social engagement, followed by 2 minutes of maternal unresponsiveness and concluded by 2 minutes of social reunion). Results: Principal Component Analysis of the RSA scores yielded a one-factor solution explaining over 70% of the variance, and so mean of RSA scores was used as the index of overall vagal tone, and the difference between overall and RSA during the Still Face as the estimate of vagal withdrawal. There were no main effects of prenatal maternal depression or anxiety on vagal tone or vagal withdrawal. However, there were significant prenatal stress by sex of infant interactions. Follow-up analyses revealed that increasing maternal depression and anxiety at 20 weeks gestation were associated with decreasing vagal tone in males and increasing vagal tone in females. Vagal withdrawal in response to the still face showed similar patterns i.e. decreased in males and increased in girls with elevated maternal anxiety at 32 weeks gestation. These associations were not explained by possible confounding variables assessed in pregnancy, nor by postnatal maternal depression and anxiety. Conclusions: The findings support the fetal origins hypothesis for vagal tone and vagal withdrawal, but only in interaction with sex of the infant. Longitudinal study is required to determine conditions under which increasing vagal tone and withdrawal in girls associated with prenatal depression and anxiety, and decreasing vagal tone and withdrawal in boys, are associated with later resilience or vulnerability to psychopathology.

No description available.

Empirical evidence suggests that complex cognitive processes such as decision-making can be influenced by incidental affect (i.e. emotional states unrelated to the decision), which may have importance implications for furthering our understanding and treatment of mood disorders. Following up on previous behavioral findings suggesting that sad mood leads to biases in social decision-making, the present research first investigated how such biases are implemented in the brain. Nineteen adult participants made decisions that involved accepting or rejecting monetary offers from others in an Ultimatum Game (a well known economic task), while undergoing functional magnetic resonance imaging (fMRI). Prior to each set of decisions, participants watched a short video clip aimed at inducing either sadness or a neutral emotional state. Results indicated that sad participants rejected more "unfair" offers than those in the neutral condition, thereby replicating our previous findings. Neuroimaging analyses revealed that receiving unfair offers while in a sad mood elicited activity in brain areas related to aversive emotional states and somatosensory integration (anterior insula) and to cognitive conflict (anterior cingulate cortex). Sad participants also showed a diminished sensitivity in neural regions associated with reward processing (ventral striatum). Importantly, insular activation uniquely mediated the relationship between sadness and decision bias, demonstrating how subtle mood states can be integrated at the neural level to bias decision-making.In a second study, we assessed to what extent such affect infusion in decision-making may translate to clinical depression, a mood disorder involving chronic sad affect. Fifteen depressed and twenty-three nondepressed individuals made decisions to accept or reject monetary offers from other players in the Ultimatum Game. Like transiently sad, but healthy, individuals, depressed participants reported a more negative emotional reaction to unfair offers. However, unlike sad healthy individuals, they accepted significantly more of these offers than did controls. A positive relationship was observed in the depressed group, but not in controls, between acceptance rates of unfair offers and resting cardiac vagal tone, a physiological index of emotion regulation capacity. These findings suggest distinct biasing processes in depression, which may be related to higher reliance on regulating negative emotion.

Theory and research suggests a link between self-esteem and cardiac vagal tone (parasympathetic nervous system influence on the heart). A literature review suggests that vagal tone protects the body against physiological threat responding (e.g., sympathetic responding) and that vagal tone is highest when we feel secure. Terror management theory posits that humans, who live in a largely symbolic world, derive feelings of security and protection from threat by way of acquiring and maintaining self-esteem. Thus we hypothesized that if vagal tone provides physiological security, and we derive a sense of security through symbolic means by way of self-esteem, then high or increased self-esteem should lead to high or increased vagal tone. To test this hypothesis we conducted two studies in which we manipulated self-esteem by giving participants positive or negative feedback. We predicted that positive feedback would lead to higher vagal tone than negative feedback. Consistent with these predictions, in both studies we found indications that positive feedback increased vagal tone relative to negative feedback. In Study 2, to more fully test our theoretical perspective we induced threat by leading participants to believe they would receive electric shocks. We predicted that both self-esteem and vagal tone would buffer against sympathetic threat responding. Consistent with our model we found that the positive feedback eliminated the sympathetic response to threat of shock that was elicited in the negative feedback condition. Also consistent with our model, higher vagal tone predicted lower sympathetic responding to threat of shock. We discuss future directions for this research and implications for physical health.

Autism Spectrum Disorder (ASD) is a neurodevelopmental disorder characterised by impaired socialisation. The current project examines the hypothesis that ASD represents a broad range of distinct disease processes typified by environmental insult(s) during a period crucial for the development of any of the systems responsible for social integration skills, sharing simply the fundamental disruption to social functioning with various, definable systemic pathologies related to the initial insult conferring the heterogeneity of the condition. ASD will therefore have both modifiable environmental factors relating to the aetio-pathogenesis of the condition and likely, remediable disease processes. Following an examination of the relevant literature this project presents the Variable Insult Model of Autism. As part of a wider research strategy, this project goes on to explore potential modifiable environmental factors in patients with ASD.Zinc deficiency was explored as a potential environmental modifiable factor involved in the pathophysiology of autism and co-morbid disease. 72 patients with ASD were compared with 234 non-ASD controls. Mean serum zinc levels in the ASD group vs. the control group were 10.01 umol/l (SD 1.52 umol/l) vs. 11.61 umol/l (SD 2.14 umol/l, with a statistically significant difference - p < 0.0001, CI 1.2 – 2.1). The findings withstood correction for age and sex, and zinc did not correlate with diet or supplement use in the ASD group. Total lymphocyte count increased as zinc increased in the ASD group with zinc levels of 10.5 umol/l or above, suggesting zinc status is poor in patients with autism and this is affecting immune function. Urinary metabolomics, quantitative PCR stool analysis and autonomic function were also explored in ASD, as biomarkers of systemic disease processes presenting potential modifiable factors. The urinary organic acids of 49 patients were analysed versus population norms. 90% of patients with ASD had at least one abnormality. A follow-up study of 122 patients revealed succinic acid and 2-hydroxyhippuric acid were significantly raised in the ASD group versus population means (p = < 0.0001 and < 0.0001 respectively). Quantitative PCR analysis was conducted on 29 patients with autism versus 7 age-matched controls. Firmicutes to Bacteriodetes ratio was significantly elevated in the autism group versus the controls 69:41 (SD 8) vs. 54:46 (SD 8) (p < 0.003). A follow-up study of 143 patients and 12 controls showed consistent abnormalities in the composition of firmicutes and bacteriodetes (p = 0.005) and this withstood correction for age and sex (p = 0.009), suggesting an on-going abnormality in gut flora composition in the ASD-cohort. Autonomic profiles were available in 45 patients with ASD. There was marked variability in vagal tone, however in 11 patients with ASD who had both autonomic profile and qPCR stool analysis there was suggestion of a positive correlation between vagal tone and microflora composition (represented by firmicutes to bacteriodetes ratio) (p < 0.003).In summary, evidence suggests there are modifiable environmental factors associated with the aetiology, pathophysiology and disease evolution in ASD, and this is worthy of further consideration and investigation. From the preliminary results presented here, zinc status is poor in ASD and may be affecting immune function; gut flora abnormalities appear common and may be affecting neurological function in ASD.

This study examined the development of attachment as it relates to co-regulation and vagal tone over the second half of the first year of life. Links to infants' attachment and developmental status were also examined. Symmetrical and unilateral co-regulated patterns of interactions at 6 months demonstrated significant linkages with attachment. Developmental status did not show direct linkages with attachment. Direct links between vagal tone and attachment were also not identified. Correlations between co-regulation and vagal tone at the 6 month time point were identified. Findings suggest an important role of co-regulation as it relates to attachment development. Future studies may benefit from evaluating the role of co-regulation as a mediating variable between vagal tone and attachment development.

No description available.

The perception of and actual ability to control emotional responses during stressful, taxing situations are important to an individual’s well-being. Studies have shown that both low perceived control and a low actual ability for emotional control are related to internalizing and externalizing problems in youth. However, significant gaps in research exist in terms of testing theoretical predictions about how perceived and actual emotional control are associated with anxiety and aggressive behavior problems, particularly among adolescents. The first goal of this study was to examine two objective measures of actual control (i.e., vagal tone and vagal regulation) and their link with anxiety and aggressive behavior problems in youth ages 11-17 years. The second goal was to examine individual differences in youths’ ability to voluntarily control their heart rate and its association with youths’ perceived control and/or anxiety and aggressive behavior. The final goal was to expand upon Scott and Weems’ (2010) recent work by testing an adapted model of control using these two measures of actual emotional control. Eighty youth (aged 11-17 years; 51% female; 37.5% African American) and their primary caregivers participated in this study. Youth completed a physiological assessment in which they watched a relaxing video, rested quietly, increased and decreased their heart rate, and performed a mildly challenging cognitive task while their heart rate, skin conductance and body temperature were measured. Youth and their caregivers also completed questionnaires measuring youths’ anxiety, aggression, and perceived control. The results indicated that resting vagal tone (i.e., high frequency – heart rate variability) was negatively associated with anxiety symptoms (and perceived anxiety control) in this adolescent sample but not aggression. Conversely, anxiety (child-reported) and aggression (parent-reported) were both associated with a maladaptive vagal augmentation in response to a challenging cognitive task. The findings also suggested there were individual differences in youths’ heart rate control (but were better at increasing it) and that less change in increasing heart rate was related to more child-reported anxiety symptoms. However, the results did not provide support for differential of prediction of anxiety symptoms versus aggressive behavior problems between control profiles.

Research indicates that learning how to regulate one’s emotions is critical to successful child development and is associated with adaptive social functioning and psychological adjustment (Dunn & Brown, 1994; Eisenberg, Fabes, Guthrie, & Reiser, 2000; Eisenberg, Fabes, & Murphy, 1996). Children’s emotion regulation abilities are thought to be influenced by both child (e.g., age, temperament) and parent characteristics (e.g., parenting behaviors, parental regulation; Eisenberg, Cumberland, & Spinrad, 1998). Resting heart rate variability (HRV) has emerged as a potentially important biomarker associated with emotion regulation (Porges, 2007; Thayer & Lane, 2000); however, there are still significant gaps in research. In particular, research indicates genetic correlates associated with HRV as well as an important role of parents in children’s emotion socialization, but research has yet to establish a strong link between parent and child HRV. Theoretically, parent and child HRV may be linked but only in specific contexts. For example, parent and child resting HRV may become more or less strongly related in the context of specific parenting behaviors, but research has yet to test this hypothesis. The present study examined the association between parenting behaviors and child resting HF-HRV (i.e., high frequency HRV), the links between parent and child resting HF-HRV, and potential moderating effects of parenting behaviors on the association in youth. Additional analyses examined associations between parent and child vagal regulation. Ninety-seven youth (11-17 years) and their caregivers (n = 81) participated in a physiological assessment and completed questionnaires assessing parenting behaviors. Results indicated that parent’s inconsistent discipline and corporal punishment were negatively associated with their child’s resting HF-HRV while positive parenting and parental involvement were positively associated. Furthermore, parent’s inconsistent discipline and parent’s involvement moderated the relationship between parent and child resting HF-HRV, such that in the context of high inconsistent discipline and high parental involvement, high parent resting HF-HRV was associated with low child resting HF-HRV. Findings add to the literature by providing evidence for the role of parenting behaviors in shaping the development of children’s HF-HRV and indicating that inconsistent discipline and parental involvement may affect the entrainment of HF-HRV in parents and their adolescent children.

abstract: This study examines the relations among three aspects of temperament (shyness, impulsivity, and effortful control), resting respiratory sinus arrhythmia (RSA) recorded during a calming film and RSA suppression during three behavioral measures of effortful control, and adjustment (anxiety and externalizing behavior) in a sample of 101 preschool-age children. Principal components analysis was used to create composites for effortful control, shyness, impulsivity, anxiety, and externalizing behavior, and hierarchical regression analysis was used to test the study hypotheses. As expected, baseline RSA was negatively related to effortful control in shy children, but was unrelated to effortful control in children who were not shy. It was hypothesized that high baseline RSA would reduce the relation between shyness and anxiety, and between impulsivity and externalizing behavior; this hypothesis was supported for externalizing behavior, but not for anxiety. The interaction between impulsivity and RSA as a predictor of externalizing was statistically independent of effortful control, indicating that these are unique effects. Finally, it was hypothesized that RSA suppression would be positively related to effortful control for children low, but not high, in shyness. There was a marginal interaction between shyness and RSA suppression, with RSA suppression marginally negatively related to EC for children low in shyness, but unrelated to effortful control for children high in shyness; the direction of this association was opposite predictions. These findings indicate that RSA is more strongly related to effortful control for children high in shyness, and that it consequently may not be appropriate to use RSA as an index of EC for all children. This study also draws attention to the need to consider the context in which baseline RSA is measured because a true baseline may not be obtained for shy children if RSA is measured in an unfamiliar laboratory context. The finding that high RSA moderated (but did not eliminate) the relation between impulsivity and externalizing behavior is consistent with the conceptualization of RSA as a measure of self-regulation, but further research is needed to clarify the mechanism underlying this effect. / Dissertation/Thesis / M.A. Psychology 2012