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While research has linked alterations in functional connectivity of the default mode (DMN), cognitive control (CCN), and salience networks (SN) to depression and anxiety, little research has examined whether these alterations may be premorbid vulnerabilities. This study examined resting state functional connectivity (RSFC) of the CCN, DMN, and SN as markers of risk for developing an onset of a depressive or anxiety disorder in adolescents at high familial risk for these disorders. At baseline, 135 participants aged 11–17 completed resting-state functional magnetic resonance imaging, measures of internalizing symptoms, and diagnostic interviews to assess history of depressive and anxiety disorders. Diagnostic assessments were completed again at 9- or 18-month follow-up for 112 participants. At baseline, increased CCN connectivity to areas of the visual network, and decreased connectivity between the left SN and the precentral gyrus, predicted an increased likelihood of a new onset at follow-up. Increased connectivity between the right SN and postcentral gyrus at baseline predicted first episode onsets at follow-up. Altered connectivity between these regions may represent a risk factor for developing a clinically significant onset of an internalizing disorder. Results may have implications for understanding the neural bases of internalizing disorders for early identification and prevention efforts.

Youth with chronic pain and their parents face uncertainty regarding their diagnosis, treatment, and prognosis. Given the uncertain nature of chronic pain and high comorbidity of anxiety among youth, intolerance of uncertainty (IU) may be critical to the experience of pediatric chronic pain. This study longitudinally examined major tenets of the Interpersonal Fear Avoidance Model of Pain and included parent and youth IU as key factors in the model. Participants included 152 youth with chronic pain (Mage = 14.23 years; 72% female) and their parents (93% female). At baseline, parents and youth reported on their IU and catastrophic thinking about youth pain; youth reported on their fear of pain, pain intensity, and pain interference; and parents reported on their protective responses to child pain. Youth reported on their pain interference 3 months later. Cross-lagged panel models, controlling for baseline pain interference, showed that greater parent IU predicted greater parent pain catastrophizing, which, in turn, predicted greater parent protectiveness, greater youth fear of pain, and subsequently greater youth 3-month pain interference. Youth IU had a significant indirect effect on 3-month pain interference through youth pain catastrophizing and fear of pain. The results suggest that parent and youth IU contribute to increases in youth pain interference over time through increased pain catastrophizing, parent protectiveness, and youth fear of pain. Thus, parent and youth IU play important roles as risk factors in the maintenance of pediatric chronic pain over time and may be important targets for intervention.

Background: Cost-efficient and non-invasive predictors of antidepressant response to repetitive transcranial magnetic stimulation (rTMS) are required. The personality vulnerabilities—neuroticism and self-criticism—are associated with antidepressant outcomes in other modalities; however, self-criticism has not been examined in response to rTMS, and the literature on neuroticism and rTMS is inconsistent. Methods: This naturalistic, 4-week study involved daily dorsolateral prefrontal cortex (DLFPC) rTMS for major depression (15 unipolar, 2 bipolar). Participants completed the Big Five Inventory (neuroticism) and the Depressive Experiences Questionnaire (self-criticism) at baseline and at the end of treatment. Changes in depressive symptoms, as rated by the clinician, were quantified using the 21-item Hamilton Depression Rating Scale. Given the inconsistencies in data regarding the stability of neuroticism in patients receiving rTMS, we performed a systematic review and quantitative meta-analysis of trials examining rTMS and neuroticism. Results: rTMS significantly improved depressive symptoms, and this was predicted by higher levels of self-criticism but not neuroticism. Self-criticism was stable over the 4 weeks of rTMS; however, neuroticism decreased, and this was not related to decreases in depressive symptoms. Our quantitative meta-analysis of 4 rTMS trials in major depression ( n = 52 patients) revealed decreases in neuroticism, with a moderate effect size. Limitations: Our results are limited by a small sample size, and the absence of a sham-rTMS group. Our meta-analysis included only 4 trials. Conclusion: Highly self-critical patients appear to benefit more from rTMS than less self-critical patients. Neuroticism, a conceptually similar but distinct personality domain, does not appear to predict antidepressant response, yet this vulnerability factor for depression decreases after rTMS.

COVID-19 restrictions led to reduced levels of physical activity, increased screen usage, and declines in mental health in youth, however, in-depth understandings of the experiences of high school student-athletes have yet to be explored. To describe the experiences of the COVID-19 pandemic on student-athletes’ physical activity, social connection, and mental health, 20 high school student-athletes living in Calgary, Alberta participated in semi-structured interviews, designed using phenomenography. Participants reported variations in physical activity, social connections, and mental health which were influenced by stay-at-home restrictions and weather. Access to resources, changes to routines, online classes, and social support all influenced engagement in physical activity. School and sports provided opportunities for in-person social connections, impacted by the onset of the pandemic. Participants reported their mental health was influenced by social connections, online classes, and physical activity. Findings from this study will inform the development of resources for high school student-athletes amidst COVID-19.

Adverse childhood experiences are significant risk factors in the development of adolescent borderline personality disorder symptoms (BPDs). Theorists have posited that two personality vulnerabilities factors, self-criticism and dependency, may inform our understanding of this relationship. However, no research has examined the associations between early negative experiences, personality vulnerabilities, and adolescent BPDs. The current study aimed to identify profiles of dependency and self-criticism to examine the associations of these profiles with cumulative forms of childhood maltreatment (CM) and BPDs as well as to explore the mediating and moderating role of vulnerable personality profiles in the relationship between cumulative CM and BPDs. Two hundred and forty-one nonclinical and clinical adolescents participated in the study (Mage= 16.37,SD= 1.84). The findings indicated three different profiles: average dependent profile, dependent and self-critical profile, and self-critical profile. Individuals in the average dependent profile presented lower levels of CM and BPDs. Mediation analyses showed that relative to the average dependent profile, a higher cumulative CM history predicted a higher probability of belonging in the dependent and self-critical profile or the self-critical profile and, in turn, this was associated with higher levels of BPDs. No moderating effects of profiles of dependency and self-criticism were found.

Parenting has been robustly associated with offspring psychosocial development, and these effects are likely reflected in brain development. However, the claim that parenting influences offspring brain development in humans, as measured by structural and functional Magnetic Resonance Imaging (MRI), is subject to numerous methodological limitations. To interpret the state of the parenting and brain development literature, we review these limitations. Four limitations are common. First, most literature has been cross-sectional. Where longitudinal, studies rarely included multiple assessments of brain structure or function, precluding measurement of actual brain development. Second, parenting has largely been measured via selfor parent-report, as opposed to observational assessment. Third, there has been a focus on extreme forms of developmental adversity which do not necessarily lie on a continuum with normative parenting. Fourth, although not a limitation per se, studies have generally focused on negative as opposed to positive parenting behaviours. While not all studies are subject to all these limitations, the study of parenting in relation to offspring brain development is in its infancy.

Temperament is a core aspect of children's psychological functioning and is assumed to be at least somewhat stable across childhood. However, little research has assessed the stability of temperament from early childhood to early adolescence. Moreover, few studies have examined the influence of measurement and analytic methods on the stability of early temperament over periods of more than a few years. We obtained laboratory observations and mother and father reports of temperamental negative and positive emotionality and effortful control from 559 three–year–olds. Approximately nine years later, children and both parents completed questionnaire measures of similar temperament constructs. Zero–order correlations revealed greater within–informant than cross–informant stability. In addition, compared with parent reports, early childhood laboratory measures showed greater convergent and divergent validity with child, mother, and father reports at age 12. Finally, latent temperament variables at age 3 composed of laboratory and parent–report measures and latent variables at age 12 composed of parent and child reports showed moderate stability. There was also a weak but significant association of early effortful control with later negative and positive emotionality. Results have implications for assessing temperament and knowledge of the stability of temperament across childhood. Copyright © 2018 European Association of Personality Psychology

Several studies have demonstrated that child maltreatment (psychological, physical, and sexual abuse, and neglect) may be a significant factor in the development of pathological personality traits that increase the risk for suicidal ideation and behavior from adolescence to adulthood. Currently, the challenge is to understand how different forms of early negative experiences render an individual prone to develop specific personality traits and, in turn, be more vulnerable to suicide risk. To understand the relationship between childhood maltreatment and personality dimensions in suicide risk, our study aims to explore the role of self-criticism and dependency, two different pathological personality traits, as potential mediators of the link between different types of childhood maltreatment and suicide risk in young adults. For this purpose, 306 students from three Italian public universities were recruited. We used the Italian version of the Childhood Experience of Care and Abuse Questionnaire (CECA.Q) to assess experiences of lack of care by parents (i.e., antipathy and neglect) as well as psychological and physical abuse before the age of 17 years. The Depressive Experiences Questionnaire (DEQ) was used to assess the personality dimensions of self-criticism and dependency, and the Suicide History Self-Rating Screening Scale was administered to assess suicide risk. Results revealed that lack of care and psychological abuse were significantly associated with suicide risk and this association was partially mediated by the maladaptive personality dimension of self-criticism. These findings suggest that the combined effect of specific forms of dysfunctional parental behavior during childhood and the development of rigid and dysfunctional negative personality traits may increase the risk for suicidal ideation and behavior during adulthood.

Background Previous cross-sectional findings from adolescents and adults with Bulimia Nervosa (BN) suggest disturbances in fronto-striatal and cingulo-opercular task control circuits that support self-regulatory processes, including the resolution of cognitive conflict. Herein, we used longitudinal data to examine the developmental trajectories of such disturbances and how the functioning of these circuits relates to changes in BN symptoms over adolescence. Methods Thirty-two adolescent females with BN symptoms and 28 healthy control (HC) adolescents participated in the study. Functional magnetic resonance images (fMRI) during performance of a Simon task were acquired at three time points within 2-year intervals over adolescence. From the initial sample, 70% and 30% of the participants completed the second and third time points, respectively. Participants who completed all study time points did not differ from those lost to attrition on baseline demographic characteristics or any outcome measures. Using a region-of-interest approach, growth curve models tested group differences in the trajectory of conflict-related activation in task control circuits over time. Cross-lagged panel models examined transactional relationships between conflict-related activation in the same regions and BN symptoms over time. Results Growth curve models revealed different trajectories of conflict-related activation in right task control regions across BN and HC adolescents, such that HC but not BN adolescents showed activation decreases over time. These group differences were greatest when including only the BN adolescents whose symptoms remitted over time. Cross-lagged panel models revealed that less frequent bulimic episodes at first follow-up predicted later increases in conflict-related activation in bilateral task control regions. Conclusions These longitudinal findings suggest overengagement of task control circuits in BN adolescents, especially those most resilient to persistent illness. Such overengagement may compensate for regulatory disturbances, allowing them to regulate eating behaviors over development. Thus, task control circuits may constitute targets for early interventions that enhance self-regulatory control.

There is substantial evidence that personality traits, such as self-criticism and dependency, predict the development of depression and anxiety symptoms, as well as depressive episodes. However, it is unknown whether self-criticism and dependency predict the first onset of depressive and anxiety disorders, and unclear how to characterize dynamic mechanisms by which these traits, stressful life events, and psychopathology influence one another over time. In this study, 550 female adolescents were assessed at baseline, 528 and 513 of whom were assessed again at Waves 2 and 3, respectively, over the course of 18 months. Self-criticism and dependency were assessed with self-report inventories, depressive and anxiety disorders were assessed with diagnostic interviews, and stressful life events were assessed via semistructured interview. Logistic regression analyses showed that self-criticism and dependency significantly predicted the first onset of nearly all depressive and anxiety disorders (significant polychoric rs ranged from .15-.42). Subsequent path analyses focused on prediction of depression, and supported several conceptual models of personality-stress-psychopathology relationships. In particular, Personality × Stress interactions were evident for both dependency and self-criticism. These interactions took the form of dual vulnerability, such that stressful life events predicted an increased probability of a later depressive disorder only at low levels of each trait. Results suggest the traits of self-criticism and dependency are important to consider in understanding who is at risk for depressive and anxiety disorders. (PsycINFO Database Record

Evidence suggests that parenting is associated cross-generationally and that children’s genes may elicit specific parenting styles (evocative gene-environment correlation). This study examined whether the effect of children’s genotype, specifically 5-HTTLPR, on mothers’ parenting behaviors was moderated by her own parenting experiences from her mother. Two independent samples of three-year-olds (N = 476 and 405) were genotyped for the serotonin transporter gene, and observational measures of parenting were collected. Mothers completed measures of the parenting they received as children. The child having a short allele on 5-HTTLPR was associated with more maternal hostility (sample 1 and 2) and with less maternal support (sample 1), but only if the mother reported lower quality grandmothers’ parenting (abuse and indifference in Sample 1 and lower levels of grandmother care in Sample 2). Results support the possibility of a moderated evocative gene-environment correlation.

Self-criticism has been shown to be a vulnerability factor that can lead to and maintain depression. We examined the moderating effect of fear of receiving compassion from others on the positive association between self-criticism and depression. Self-report measures were administered to four separate samples (total N = 701) varying in age (students and community adults) and cultural context (Canada, England, and Portugal). Two different measures of self-criticism and of depression were administered to investigate the generalizability of results. Self-criticism, depression, and fear of compassion from others were positively related to one another in all samples. As predicted, fear of compassion from others exerted a moderating effect on the relationship between self-criticism and depression. Low fear of compassion from others weakened the depressogenic effect of self-criticism, while high fear of compassion from others exacerbated the effect. Thus, a self-critic's ability to be open and responsive to care and support from others protected against depression. The aggregate moderating effect across the four studies was of medium size (d + = .53) and highly significant, indicating a robust phenomenon. Implications for working with self-critical depressed patients are discussed.

Many recent studies have explored the potential links between attachment style dimensions, personality vulnerability factors for psychopathology, and psychological and behavioral problems, particularly those along the internalizing and externalizing spectrum. However, previous studies have not examined these links within a structural equation model that can examine multiple predictors and outcomes, and therefore have not fully investigated the specificity of links between these factors. This cross-sectional study examined the mediating role of self-criticism in the relationship between attachment style dimensions and internalizing and externalizing problems. The sample included 420 nonclinical adolescents aged 14–20 years who were recruited in school settings and completed self-reported measures of attachment style dimensions (Attachment Style Questionnaire), self-criticism (Depressive Experiences Questionnaire), and internalizing and externalizing problems (Youth Self-Report). Structural equation modeling was used to test the proposed mediation model and to ascertain direct and indirect effects among study variables. Results shown that self-criticism mediated the link between both attachment avoidance and anxiety, and internalizing problems. Results were not moderated by gender. Results suggest that self-criticism is associated with psychopathology during adolescence, and accounts for the associations of attachment style dimensions with internalizing and externalizing problems.

Seventy-nine 3-year olds and their mothers participated in a laboratory-based task to assess maternal hostility. Mothers also reported their behavioral regulation of their child. Seven years later, functional magnetic resonance imaging data were acquired while viewing emotional faces and completing a reward processing task. Maternal hostility predicted more negative amygdala connectivity during exposure to sad relative to neutral faces with frontal and parietal regions as well as more negative left ventral striatal connectivity during monetary gain relative to loss feedback with the right posterior orbital frontal cortex and right inferior frontal gyrus. In contrast, maternal regulation predicted enhanced cingulo-frontal connectivity during monetary gain relative to loss feedback. Results suggest parenting is associated with alterations in emotion and reward processing circuitry 7-8 years later. [ABSTRACT FROM AUTHOR]

Several studies have demonstrated that child maltreatment (psychological, physical, and sexual abuse, and neglect) may be a significant factor in the development of pathological personality traits that increase the risk for suicidal ideation and behavior from adolescence to adulthood. Currently, the challenge is to understand how different forms of early negative experiences render an individual prone to develop specific personality traits and, in turn, be more vulnerable to suicide risk. To understand the relationship between childhood maltreatment and personality dimensions in suicide risk, our study aims to explore the role of self-criticism and dependency, two different pathological personality traits, as potential mediators of the link between different types of childhood maltreatment and suicide risk in young adults. For this purpose, 306 students from three Italian public universities were recruited. We used the Italian version of the Childhood Experience of Care and Abuse Questionnaire (CECA.Q) to assess experiences of lack of care by parents (i.e., antipathy and neglect) as well as psychological and physical abuse before the age of 17 years. The Depressive Experiences Questionnaire (DEQ) was used to assess the personality dimensions of self-criticism and dependency, and the Suicide History Self-Rating Screening Scale was administered to assess suicide risk. Results revealed that lack of care and psychological abuse were significantly associated with suicide risk and this association was partially mediated by the maladaptive personality dimension of self-criticism. These findings suggest that the combined effect of specific forms of dysfunctional parental behavior during childhood and the development of rigid and dysfunctional negative personality traits may increase the risk for suicidal ideation and behavior during adulthood.

Little research has examined the effect of subtypes of social withdrawal on the development of psychopathology across childhood. Parents of 493 children (220 females) completed a measure of their child's conflicted shyness and social disinterest as well as the Child Behaviour Checklist (CBCL) when their child was age 3, and again at age 6. When children were age 9, parents completed the CBCL. From 3 to 6, conflicted shyness predicted increases in anxiety symptoms in boys and girls, and predicted depressive symptoms in boys. From 6 to 9, social disinterest predicted increases in anxiety symptoms in girls and boys, and predicted increases in depressive symptoms in boys. In addition, in boys, conflicted shyness at age 6 predicted increases in externalizing symptoms at age 9. Conflicted shyness appears to be particularly problematic in early to middle childhood, while social disinterest appears to be more maladaptive in later childhood, with some differences by gender.

The Depressive Experiences Questionnaire (DEQ) is a self-report measure that assesses self-criticism and dependency, 2 personality traits that confer vulnerability to depression (Blatt, 2004). Over several decades, different, shortened versions of the DEQ have been constructed to offer an alternative to the complex scoring procedure of the original DEQ. This study explores the factor structure as well as the construct and convergent validity of the DEQ by comparing a clinical and nonclinical sample. We also compared the original DEQ with 5 shortened versions. There were 621 participants (358 university students and 263 outpatients). Fit indexes for models of the original DEQ did not meet minimum fit criteria. Moreover, the only versions with satisfactory fit were the Theoretical Depressive Experiences Questionnaire – 21 (TDEQ –21) and the Theoretical Depressive Experiences Questionnaire – 12 (TDEQ–12), which also showed acceptable construct and convergent validity. Finally, the diagnostic and clinical applicability of the DEQ is discussed.

The link between parental depressive history and parenting styles is well established, as is the association of parenting with child psychopathology. However, little research has examined whether a depressive history in one parent predicts the parenting style of the other parent. As well, relatively little research has tested transactional models of the parenting–child psychopathology relationship in the context of parents' depressive histories. In this study, mothers and fathers of 392 children were assessed for a lifetime history of major depression when their children were 3 years old. They then completed measures of permissiveness and authoritarianism and their child's internalizing and externalizing symptoms when children were 3, 6, and 9 years old. The results showed that a depressive history in one parent predicted the other parent's permissiveness. Analyses then showed that child externalizing symptoms at age 3 predicted maternal permissiveness and authoritarianism and paternal permissiveness at age 6. Maternal permissiveness at age 6 predicted child externalizing symptoms at age 9. No relationships in either direction were found between parenting styles and child internalizing symptoms. The results highlight the importance of considering both parents' depressive histories when understanding parenting styles, and support transactional models of parenting styles and child externalizing symptoms.

The current study evaluated the psychometric properties of the Italian validation of the Depressive Experiences Questionnaire (DEQ), conceived as a measure of self-criticism and dependency, i.e. two personality factors acting, according to Blatt (2004), as risk factors for depression in particular and psychopathology in general. A series of standardized measures [Beck Depression Inventory-II (BDI-II), DEQ, Symptom Checklist-90-R (SCL-90-R), Millon Clinical Multiaxial Inventory, 3rd edition (MCMI-III)] was administered to three samples (i.e., students, community and clinical). Factorial validity was evaluated along with convergent and predictive validity. In order to evaluate the reliability and internal consistency, a specific subgroup of participants was retested on the DEQ and BDI-II. Results showed correlations between DEQ dimensions and some personality traits of the MCMI-III. The traditional three-factor model of the DEQ structure as identified by principal component analysis appears to be as stable factors as typically found in American samples, although some items showed elevated cross-loading or low loadings on any factor. Clinical and diagnostic implications of the findings will be discussed.

Objective Cross-sectional data suggest functional and anatomical disturbances in inferior and orbital frontal regions in bulimia nervosa (BN). Using longitudinal data, we investigated whether reduced cortical thickness (CT) in these regions arises early and persists over adolescence in BN, independent of symptom remission, and whether CT reductions are markers of BN symptoms. Method A total of 33 adolescent females with BN symptoms (BN or other specified feeding or eating disorder) and 28 healthy adolescents participated in this study. Anatomical magnetic resonance imaging and clinical data were acquired at 3 time points within 2-year intervals over adolescence, with 31% average attrition between assessments. Using a region-of-interest approach, we assessed group differences in CT at baseline and over time, and tested whether between- and within-subject variations in CT were associated with the frequency of BN symptoms. Results Reduced CT in the right inferior frontal gyrus persisted over adolescence in BN compared to healthy adolescents, even in those who achieved full or partial remission. Within the BN group, between-subject variations in CT in the inferior and orbital frontal regions were inversely associated with specific BN symptoms, suggesting, on average over time, greater CT reductions in individuals with more frequent BN symptoms. Conclusion Reduced CT in inferior frontal regions may contribute to illness persistence into adulthood. Reductions in the thickness of the inferior and orbital frontal regions may be markers of specific BN symptoms. Because our sample size precluded correcting for multiple comparisons, these findings should be replicated in a larger sample. Future study of functional changes in associated fronto-striatal circuits could identify potential circuit-based intervention targets.

Considerable research exists documenting the relationship between maternal mood disorders, primarily major depressive disorder (MDD), and a variety of negative child outcomes. By contrast, research exploring the reverse pathway whereby child traits are associated with later maternal mood disorders is much more limited. We examined whether young children’s temperament and psychopathology predicted maternal mood disorders approximately 6 years later. Child temperament and symptoms were assessed at age three using semi-structured diagnostic interviews and parent-report inventories. Maternal psychopathology was assessed with semi-structured interviews when children were three and nine years old. Mothers also reported on their marital satisfaction when children were three and six years old. Child temperamental negative affectivity (NA), depressive symptoms, and externalizing behavior problems significantly predicted maternal mood disorders over and above prior maternal mood, anxiety, and substance disorders. The link between children’s early externalizing symptoms and maternal mood disorders 6 years later was mediated by maternal marital satisfaction 3 years after the initial assessment. These findings suggest that early child temperament and psychopathology contribute to risk for later maternal mood disorders both directly and through their impact on the marital system. Research indicates that effective treatment of maternal depression is associated with positive outcomes for children; however, this study suggests that treating early child problems may mitigate the risk of later maternal psychopathology.

BackgroundAccording to diathesis–stress models, personality traits, such as negative emotionality (NE) and positive emotionality (PE), may moderate the effects of stressors on the development of depression. However, relatively little empirical research has directly examined whether NE and PE act as diatheses in the presence of stressful life events, and no research has examined whether they moderate the effect of disaster exposure on depressive symptoms. Hurricane Sandy, the second costliest hurricane in US history, offers a unique opportunity to address these gaps.MethodA total of 318 women completed measures of NE and PE 5 years prior to Hurricane Sandy. They were also assessed for lifetime depressive disorders on two occasions, the latter occurring an average of 1 year before the hurricane. Approximately 8 weeks after the disaster (mean = 8.40, s.d. = 1.48 weeks), participants completed a hurricane stress exposure questionnaire and a measure of current depressive symptoms.ResultsAdjusting for lifetime history of depressive disorders, higher levels of stress from Hurricane Sandy predicted elevated levels of depressive symptoms, but only in participants with high levels of NE or low levels of PE.ConclusionsThese findings support the role of personality in the development of depression and suggest that personality traits can be useful in identifying those most vulnerable to major stressors, including natural disasters.

Positive parenting has been related both to lower cortisol reactivity and more adaptive temperament traits in children, whereas elevated cortisol reactivity may be related to maladaptive temperament traits, such as higher negative emotionality (NE) and lower positive emotionality (PE). However, no studies have examined whether hypothalamic-pituitary-adrenal axis activity, as measured by cortisol reactivity, moderates the effect of the quality of the parent-child relationship on changes in temperament in early childhood. In this study, 126 3-year olds were administered the Laboratory Temperament Assessment Battery (Lab-TAB; Goldsmith et al., 1995) as a measure of temperamental NE and PE. Salivary cortisol was collected from the child at 4 time points during this task. The primary parent and the child completed the Teaching Tasks battery (Egeland et al., 1995), from which the quality of the relationship was coded. At age 6, children completed the Lab-TAB again. From age 3 to 6, adjusting for age 3 PE or NE, a better quality relationship with their primary parent predicted decreases in NE for children with elevated cortisol reactivity and predicted increases in PE for children with low cortisol reactivity. Results have implications for our understanding of the interaction of biological stress systems and the parent-child relationship in the development of temperament in childhood.