Functional connectivity of the amygdala in early-childhood-onset depression

Developmental implications of children's brain networks and learning

The human brain works as a synergistic system where information exchanges between functional neuronal networks. Rudimentary networks are observed in the brain during infancy. In recent years, the question of how functional networks develop and mature in children has been a hotly discussed topic. In this review, we examined the developmental characteristics of functional networks and the impacts of skill training on children's brains. We first focused on the general rules of brain network development and on the typical and atypical development of children's brain networks. After that, we highlighted the essentials of neural plasticity and the effects of learning on brain network development. We also discussed two important theoretical and practical concerns in brain network training. Finally, we concluded by presenting the significance of network training in typically and atypically developed brains.

The impact of age of onset on amygdala intrinsic connectivity in major depression

BACKGROUND

Early-onset major depressive disorder (EO-MDD), beginning during childhood and adolescence, is associated with more illness burden and a worse prognosis than adult-onset MDD (AO-MDD), but little is known about the neural features distinguishing these subgroup phenotypes. Functional abnormalities of the amygdala are central to major depressive disorder (MDD) neurobiology; therefore, we examined whether amygdala intrinsic connectivity (IC) can differentiate EO-MDD from AO-MDD in a cohort of adult MDD patients.

SUBJECTS AND METHODS

Twenty-one EO-MDD (age of onset ≤18 years), 31 AO-MDD patients (age of onset ≥19 years), and 19 healthy controls (HCs) underwent resting-state functional magnetic resonance imaging (7 minutes). Amygdala seed-based resting-state functional connectivity was compared between groups.

RESULTS

AO-MDD patients showed loss of inverse left amygdala-left dorsolateral prefrontal cortex IC and increased inverse left amygdala-left inferior parietal IC, compared to both HCs and EO-MDD. EO-MDD showed a switch from inverse to positive IC with right dorsomedial prefrontal cortex, compared to HCs and AO-MDD. This effect was removed when we controlled for illness burden.

CONCLUSION

Alterations in amygdala IC with the default-mode network were specifically related to EO-MDD, whereas amygdala IC with executive cognitive control regions was preferentially disrupted in AO-MDD. Increased illness burden, an important clinical marker of EO-MDD, accounted for its specific effects on amygdala IC. Brain imaging has the potential for validation of clinical subtypes and can provide markers of prognostic value in MDD patients.

Reduced fronto-amygdalar connectivity in adolescence is associated with increased depression symptoms over time

Depression is common among adolescents, affecting greater than 12% of youth in a given year. Studies have shown aberrant amygdala connectivity in depressed adolescents, compared with controls; however, no studies have examined whether these abnormalities precede and heighten risk for depressive symptom expression. This study used resting state functional connectivity (RSFC) magnetic resonance imaging to examine neurobiological markers of escalating depression symptoms in adolescents (ages 12-16 years; free from psychopathology at baseline). Of a large sample of adolescents, 18 showed ≥ 1 S.D. increase in depression scale t-scores over time ("escalators"; time to escalation ranging from 6 to 54 months in follow up) and were matched and compared to 19 youth showing stable CDI scores over time ("controls"). Whole-brain analyses on baseline RSFC data using an amygdala seed region-of-interest (ROI) showed that controls had greater RSFC, relative to escalators, between the right amygdala and left inferior frontal and supramarginal gyrus and right mid-cingulate cortex. Additionally, relative to escalators, control youth had less RSFC between the left amygdala and cerebellum. Findings suggest a possible neurobiological marker of increasing depressive symptoms during adolescence, characterized in part by reduced fronto-limbic connectivity, suggesting a premorbid deficiency in top-down emotional regulation.

Emotion regulation as a transdiagnostic factor in the development of internalizing and externalizing psychopathology: Current and future directions

In response to rapidly growing rates of comorbidity among psychiatric disorders, clinical scientists have become interested in identifying transdiagnostic processes that can help explain dysfunction across diagnostic categories (e.g., Kring & Sloan, 2009). One factor that has received a great deal of attention is that of emotion regulation, namely, the ability to modulate the intensity and/or duration of emotional states (e.g., Cicchetti, Ackerman, & Izard, 1995; Gross, 1998). Recent theoretical and empirical work has begun to emphasize the role that emotion regulation plays in the temporal comorbidity between internalizing and externalizing conditions (e.g., Aldao & De Los Reyes, 2015; De Los Reyes & Aldao, 2015; Drabick & Kendall, 2010; Jarrett & Ollendick, 2008; Patrick & Hajcak, 2016). However, close inspection of this work reveals two very pertinent areas of growth: (a) this literature is characterized by mixed findings that are likely explained, in part, by methodological heterogeneity; and (b) emotion regulation tends to be studied in relatively narrow terms. To address these issues, we provide a series of recommendations for facilitating cross-study comparisons and leveraging multifaceted approaches to studying emotion regulation processes within a developmental psychopathology framework. We hope that our perspective can enhance the organization and growth of this very important area of inquiry, and ultimately result in more effective prevention and treatment programs.

Insula and amygdala resting-state functional connectivity differentiate bipolar from unipolar depression

OBJECTIVE

Distinguishing depressive episodes due to bipolar disorder (BD) or major depressive disorder (MDD) solely on clinical grounds is challenging. We aimed at comparing resting-state functional connectivity (rsFC) of regions subserving emotional regulation in similarly depressed BD and MDD.

METHOD

We enrolled 76 in-patients (BD, n = 36; MDD, n = 40) and 40 healthy controls (HC). A seed-based approach was used to identify regions showing different rsFC with the insula and the amygdala. Insular and amygdalar parcellations were then performed along with diagnostic accuracy of the main findings.

RESULTS

Lower rsFC between the left insula and the left mid-dorsolateral prefrontal cortex and between bilateral insula and right frontopolar prefrontal cortex (FPPFC) was observed in BD compared to MDD and HC. These results were driven by the dorsal anterior and posterior insula (PI). Lower rsFC between the right amygdala and the left anterior hippocampus was observed in MDD compared to BD and HC. These results were driven by the centromedial and laterobasal amygdala. Left PI/right FPPC rsFC showed 78% accuracy differentiating BD and MDD.

CONCLUSION

rsFC of amygdala and insula distinguished between depressed BD and MDD. The observed differences suggest the possibility of differential pathophysiological mechanisms of emotional dysfunction in bipolar and unipolar depression.

Depression and Anxiety in Preschoolers: A Review of the Past 7 Years

This article reviews recent empirical literature on the prevalence, correlates, assessment, and treatment of preschool-onset internalizing disorders. Major advances in the acceptance and recognition of both preschool-onset depression and anxiety have occurred over the past decade. This work has been greatly enhanced by the discovery of genetic, neural, and physiologic indicators, which further validate these constellations of symptoms in young children. Despite this growth in research, much work still needs to be done to further elucidate the cause, risk, treatment, and protective factors for preschool-onset internalizing disorders.

Probabilistic Entity-Relationship Diagram: A correlation between functional connectivity and spontaneous brain activity during resting state in major depressive disorder

BACKGROUND

Alterations of functional connectivity (FC) and spontaneous brain activity (SBA) during the resting state has been observed in subjects with major depressive disorder (MDD). Although there are many studies separately describing on the alterations of FC and SBA in major depressive disorder, their correlation are still have not been performed.

METHODS

A literature search based on Pubmed and Embase was conducted until 20 April 2016 to identify studies evaluating the correlation for the alterations between functional connectivity and spontaneous brain activity during resting-state in MDD. Meta-analyses were performed using the Probabilistic Entity-Relationship Diagram (PERD) approach to summarize the relationships among multiple factors in an intuitive manner.

RESULTS

A total of 30 studies (747 individuals with MDD and 757 healthy controls) met the inclusion criteria. In this study, we demonstrated that the functional connectivity and spontaneous brain activity, which was quantitatively measured by the primary analysis methods, was decreased in the parahippocampal gyrus, orbitofrontal cortex (OFC) and postcentral gyrus (PCG), and increased in insula and left dorsal medial prefrontal cortex (DMPFC) in MDD patients. Furthermore, we found that MDD patients presented negative correlation alterations both FC and SBA in the default mode network and the dorsal attention network, but positive correlation alterations both FC and SBA in the insular network, executive control network, the salience network and the other network.

CONCLUSIONS

Our results first suggested that there were correlation alterations between functional connectivity and spontaneous brain activity during resting-state in patients with MDD. Besides, we applied a recent meta-analysis approach (PERD) to summarize and integrate the inconsistence of the existing findings regarding the network dysfunction of MDD.

The Role of Neural Plasticity in Depression: From Hippocampus to Prefrontal Cortex

Neural plasticity, a fundamental mechanism of neuronal adaptation, is disrupted in depression. The changes in neural plasticity induced by stress and other negative stimuli play a significant role in the onset and development of depression. Antidepressant treatments have also been found to exert their antidepressant effects through regulatory effects on neural plasticity. However, the detailed mechanisms of neural plasticity in depression still remain unclear. Therefore, in this review, we summarize the recent literature to elaborate the possible mechanistic role of neural plasticity in depression. Taken together, these findings may pave the way for future progress in neural plasticity studies.

Resting-state functional connectivity of the amygdala and longitudinal changes in depression severity in adolescent depression

BACKGROUND

The incidence of major depressive disorder (MDD) rises during adolescence, yet the neural mechanisms of MDD during this key developmental period are unclear. Altered amygdala resting-state functional connectivity (RSFC) has been associated with both adolescent and adult MDD, as well as symptom improvement in response to treatment in adults. However, no study to date has examined whether amygdala RSFC is associated with changes in depressive symptom severity in adolescents.

METHOD

We examined group differences in amygdala RSFC between medication-naïve depressed adolescents (N=48) and well-matched healthy controls (N=53) cross-sectionally. We then longitudinally examined whether baseline amygdala RSFC was associated with change in depression symptoms three months later in a subset of the MDD group (N=24).

RESULTS

Compared to healthy controls, depressed adolescents showed reduced amygdala-based RSFC with the dorsolateral prefrontal cortex (DLPFC)and the ventromedial prefrontal cortex (VMPFC). Within the depressed group, more positive baseline RSFC between the amygdala and insulae was associated with greater reduction in depression symptoms three months later.

LIMITATIONS

Only a subset of depressed participants was assessed at follow-up and treatment type and delivery were not standardized.

CONCLUSIONS

Adolescent depression may be characterized by dysfunction of frontolimbic circuits (amygdala-DLPFC, amygdala-VMPFC) underpinning emotional regulation, whereas those circuits (amygdala-insula) subserving affective integration may index changes in depression symptom severity and may therefore potentially serve as a candidate biomarker for treatment response. Furthermore, these results suggest that the biomarkers of MDD presence are distinct from those associated with change in depression symptoms over time.

Amygdala functional connectivity, HPA axis genetic variation, and life stress in children and relations to anxiety and emotion regulation

Internalizing pathology is related to alterations in amygdala resting state functional connectivity, potentially implicating altered emotional reactivity and/or emotion regulation in the etiological pathway. Importantly, there is accumulating evidence that stress exposure and genetic vulnerability impact amygdala structure/function and risk for internalizing pathology. The present study examined whether early life stress and genetic profile scores (10 single nucleotide polymorphisms within 4 hypothalamic-pituitary-adrenal axis genes: CRHR1, NR3C2, NR3C1, and FKBP5) predicted individual differences in amygdala functional connectivity in school-age children (9- to 14-year-olds; N = 120). Whole-brain regression analyses indicated that increasing genetic "risk" predicted alterations in amygdala connectivity to the caudate and postcentral gyrus. Experience of more stressful and traumatic life events predicted weakened amygdala-anterior cingulate cortex connectivity. Genetic "risk" and stress exposure interacted to predict weakened connectivity between the amygdala and the inferior and middle frontal gyri, caudate, and parahippocampal gyrus in those children with the greatest genetic and environmental risk load. Furthermore, amygdala connectivity longitudinally predicted anxiety symptoms and emotion regulation skills at a later follow-up. Amygdala connectivity mediated effects of life stress on anxiety and of genetic variants on emotion regulation. The current results suggest that considering the unique and interacting effects of biological vulnerability and environmental risk factors may be key to understanding the development of altered amygdala functional connectivity, a potential factor in the risk trajectory for internalizing pathology.

Addressing Early Childhood Emotional and Behavioral Problems

More than 10% of young children experience clinically significant mental health problems, with rates of impairment and persistence comparable to those seen in older children. For many of these clinical disorders, effective treatments supported by rigorous data are available. On the other hand, rigorous support for psychopharmacologic interventions is limited to 2 large randomized controlled trials. Access to psychotherapeutic interventions is limited. The pediatrician has a critical role as the leader of the medical home to promote well-being that includes emotional, behavioral, and relationship health. To be effective in this role, pediatricians promote the use of safe and effective treatments and recognize the limitations of psychopharmacologic interventions. This technical report reviews the data supporting treatments for young children with emotional, behavioral, and relationship problems and supports the policy statement of the same name.

Altered Intrinsic Functional Brain Architecture in Children at Familial Risk of Major Depression

BACKGROUND

Neuroimaging studies of patients with major depression have revealed abnormal intrinsic functional connectivity measured during the resting state in multiple distributed networks. However, it is unclear whether these findings reflect the state of major depression or reflect trait neurobiological underpinnings of risk for major depression.

METHODS

We compared resting-state functional connectivity, measured with functional magnetic resonance imaging, between unaffected children of parents who had documented histories of major depression (at-risk, n = 27; 8-14 years of age) and age-matched children of parents with no lifetime history of depression (control subjects, n = 16).

RESULTS

At-risk children exhibited hyperconnectivity between the default mode network and subgenual anterior cingulate cortex/orbital frontal cortex, and the magnitude of connectivity positively correlated with individual symptom scores. At-risk children also exhibited 1) hypoconnectivity within the cognitive control network, which also lacked the typical anticorrelation with the default mode network; 2) hypoconnectivity between left dorsolateral prefrontal cortex and subgenual anterior cingulate cortex; and 3) hyperconnectivity between the right amygdala and right inferior frontal gyrus, a key region for top-down modulation of emotion. Classification between at-risk children and control subjects based on resting-state connectivity yielded high accuracy with high sensitivity and specificity that was superior to clinical rating scales.

CONCLUSIONS

Children at familial risk for depression exhibited atypical functional connectivity in the default mode, cognitive control, and affective networks. Such task-independent functional brain measures of risk for depression in children could be used to promote early intervention to reduce the likelihood of developing depression.

Alterations in amygdala-prefrontal circuits in infants exposed to prenatal maternal depression

Prenatal exposure to maternal depression is common and puts offspring at risk for developing a range of neuropsychiatric disorders. Despite its prevalence and adverse associations, neurobiological processes by which prenatal maternal depression (PMD) confers risk remain poorly understood. Maternal mood and fetal behavior were assessed between 34 and 37 gestational weeks. Using resting-state functional magnetic resonance imaging (fMRI) and diffusion MRI, we examined functional and structural connectivity within amygdala-prefrontal circuits in 64 infants (mean age=5.8±1.7 weeks) with (n=20) and without (n=44) in utero exposure to PMD. Resting fMRI and diffusion MRI both indicated atypical amygdala-prefrontal connectivity in PMD-exposed infants: Resting fMRI indicated increased inverse, or negative, functional connectivity between the amygdala and the dorsal prefrontal cortex (PFC), bilaterally, and diffusion MRI indicated decreased structural connectivity between the right amygdala and the right ventral PFC. Spectral dynamic causal modeling supported these findings suggesting altered amygdala-PFC effective (or directed) connectivity in PMD-exposed infants. Last, path analyses supported a mechanistic account relating PMD to a third-trimester fetal behavior: PMD alters amygdala-PFC connectivity, which in turn, is associated with an increase in fetal heart rate reactivity to in utero perturbation. These data suggest that the maturation and coordination of central and peripheral physiology are altered by prenatal exposure to maternal depression. To the best of our knowledge, this is the first study to directly associate infant MRI measures with a behavior-fetal heart rate response, and supports hypotheses that PMD-associated variations in the development of amygdala-PFC circuits are relevant for future neurobehavioral maturation.

Decreased anticipated pleasure correlates with increased salience network resting state functional connectivity in adolescents with depressive symptomatology

Previous studies have found dysfunctional resting state functional connectivity (RSFC) in depressed patients. Examining RSFC might aid biomarker discovery for depression. However RSFC in young people at risk of depression has yet to be examined. 35 healthy adolescents (13-18 yrs old.) were recruited. 17 scoring high on the Mood and Feelings Questionnaire (MFQ > 27 (High Risk: HR), and 18 scoring low on the MFQ < 15 (Low Risk: LR) matched on age and gender. We selected seed regions in the salience network (SN: amygdala and pregenual anterior cingulate cortex (pgACC)) and the central executive network (CEN: dorsal medial prefrontal cortex (dmPFC)). Mood and anhedonia measures were correlated with brain connectivity. We found decreased RSFC in the HR group between the amygdala and the pgACC and hippocampus and precuneus. We also found decreased RSFC in the HR group between the pgACC and the putamen and between the dmPFC and the precuneus. The pgACC RSFC with the insula/orbitofrontal cortex correlated inversely with the anticipation of pleasure in all subjects. Increased RSFC was observed between the pgACC and the prefrontal cortex and the amygdala and the temporal pole in the HR group compared to the LR group. Our findings are the first to show that adolescents with depression symptoms have dysfunctional RSFC between seeds in the SN and CEN with nodes in the Default Mode Network. As increased connectivity between the pgACC and the insula correlated with decreased ability to anticipate pleasure, we suggest this might be mechanism underlying the risk of experiencing anhedonia, a suggested biomarker for depression.

Neural Correlates of Antidepressant Treatment Response in Adolescents with Major Depressive Disorder

OBJECTIVE

The neural changes underlying response to antidepressant treatment in adolescents are unknown. Identification of neural change correlates of treatment response could (1) aid in understanding mechanisms of depression and its treatment and (2) serve as target biomarkers for future research.

METHOD

Using functional magnetic resonance imaging, we examined changes in brain activation and functional connectivity in 13 unmedicated adolescents with major depressive disorder (MDD) before and after receiving treatment with a selective serotonin reuptake inhibitor medication for 8 weeks. Specifically, we examined brain activation during a negative emotion task and resting-state functional connectivity (RSFC), focusing on the amygdala to capture networks relevant to negative emotion. We conducted whole-brain analyses to identify how symptom improvement was related to change in brain activation during a negative emotion task or amygdala RSFC.

RESULTS

After treatment, clinical improvement was associated with decreased task activation in rostral and subgenual anterior cingulate cortex and increased activation in bilateral insula, bilateral middle frontal cortices, right parahippocampus, and left cerebellum. Analysis of change in amygdala RSFC showed that treatment response was associated with increased amygdala RSFC with right frontal cortex, but decreased amygdala RSFC with right precuneus and right posterior cingulate cortex.

CONCLUSION

The findings represent a foothold for advancing understanding of pathophysiology of MDD in adolescents by revealing the critical neural circuitry changes that underlie a positive response to a standard treatment. Although preliminary, the present study provides a research platform for future work needed to confirm these biomarkers at a larger scale before using them in future target engagement studies of novel treatments.

Sleep Moderates the Association Between Response Inhibition and Self-Regulation in Early Childhood

Early childhood is a time of rapid developmental changes in sleep, cognitive control processes, and the regulation of emotion and behavior. This experimental study examined sleep-dependent effects on response inhibition and self-regulation, as well as whether acute sleep restriction moderated the association between these processes. Preschool children (N = 19; 45.6 ± 2.2 months; 11 female) followed a strict sleep schedule for at least 3 days before each of 2 morning behavior assessments: baseline (habitual nap/night sleep) and sleep restriction (missed nap/delayed bedtime). Response inhibition was evaluated via a go/no-go task. Twelve self-regulation strategies were coded from videotapes of children while attempting an unsolvable puzzle. We then created composite variables representing adaptive and maladaptive self-regulation strategies. Although we found no sleep-dependent effects on response inhibition or self-regulation measures, linear mixed-effects regression showed that acute sleep restriction moderated the relationship between these processes. At baseline, children with better response inhibition were more likely to use adaptive self-regulation strategies (e.g., self-talk, alternate strategies), and those with poorer response inhibition showed increased use of maladaptive self-regulation strategies (e.g., perseveration, fidgeting); however, response inhibition was not related to self-regulation strategies following sleep restriction. Our results showing a sleep-dependent effect on the associations between response inhibition and self-regulation strategies indicate that adequate sleep facilitates synergy between processes supporting optimal social-emotional functioning in early childhood. Although replication studies are needed, findings suggest that sleep may alter connections between maturing emotional and cognitive systems, which have important implications for understanding risk for or resilience to developmental psychopathology.

Moral competence and brain connectivity: A resting-state fMRI study

Moral competence (MC) refers to the ability to apply certain moral orientations in a consistent and differentiated manner when judging moral issues. People greatly differ in terms of MC, however, little is known about how these differences are implemented in the brain. To investigate this question, we used functional magnetic resonance imaging and examined resting-state functional connectivity (RSFC) in n=31 individuals with MC scores in the highest 15% of the population and n=33 individuals with MC scores in the lowest 15%, selected from a large sample of 730 Master of Business Administration (MBA) students. Compared to individuals with lower MC, individuals with higher MC showed greater amygdala-ventromedial prefrontal connectivity, which may reflect better ability to cope with emotional conflicts elicited by moral dilemmas. Moreover, individuals with higher MC showed less inter-network connectivity between the amygdalar and fronto-parietal networks, suggesting a more independent operation of these networks. Our findings provide novel insights into how individual differences in moral judgment are associated with RSFC in brain circuits related to emotion processing and cognitive control.

Effect of Hippocampal and Amygdala Connectivity on the Relationship Between Preschool Poverty and School-Age Depression

OBJECTIVE

In this study, the authors tested the hypothesis that poverty experienced in early childhood, as measured by income-to-needs ratio, has an impact on functional brain connectivity at school age, which in turn mediates influences on child negative mood/depression.

METHOD

Participants were from a prospective longitudinal study of emotion development. Preschoolers 3-5 years of age were originally ascertained from primary care and day care sites in the St. Louis area and then underwent annual behavioral assessments for up to 12 years. Healthy preschoolers and those with a history of depression symptoms underwent neuroimaging at school age. Using functional MRI, the authors examined whole brain resting-state functional connectivity with the left and right hippocampus and amygdala.

RESULTS

Lower income-to-needs ratio at preschool age was associated with reduced connectivity between hippocampus and amygdala and a number of regions at school age, including the superior frontal cortex, lingual gyrus, posterior cingulate, and putamen. Lower income-to-needs ratio predicted greater negative mood/depression severity at school age, as did connectivity between the left hippocampus and the right superior frontal cortex and between the right amygdala and the right lingual gyrus. Connectivity mediated the relationship between income-to-needs ratio and negative mood/depression at the time of scanning.

CONCLUSIONS

These findings suggest that poverty in early childhood, as assessed by at least one measure, may influence the development of hippocampal and amygdala connectivity in a manner leading to negative mood symptoms during later childhood.

Affective network and default mode network in depressive adolescents with disruptive behaviors

AIM

Disruptive behaviors are thought to affect the progress of major depressive disorder (MDD) in adolescents. In resting-state functional connectivity (RSFC) studies of MDD, the affective network (limbic network) and the default mode network (DMN) have garnered a great deal of interest. We aimed to investigate RSFC in a sample of treatment-naïve adolescents with MDD and disruptive behaviors.

METHODS

Twenty-two adolescents with MDD and disruptive behaviors (disrup-MDD) and 20 age- and sex-matched healthy control (HC) participants underwent resting-state functional magnetic resonance imaging (fMRI). We used a seed-based correlation approach concerning two brain circuits including the affective network and the DMN, with two seed regions including the bilateral amygdala for the limbic network and the bilateral posterior cingulate cortex (PCC) for the DMN. We also observed a correlation between RSFC and severity of depressive symptoms and disruptive behaviors.

RESULTS

The disrup-MDD participants showed lower RSFC from the amygdala to the orbitofrontal cortex and parahippocampal gyrus compared to HC participants. Depression scores in disrup-MDD participants were negatively correlated with RSFC from the amygdala to the right orbitofrontal cortex. The disrup-MDD participants had higher PCC RSFC compared to HC participants in a cluster that included the left precentral gyrus, left insula, and left parietal lobe. Disruptive behavior scores in disrup-MDD patients were positively correlated with RSFC from the PCC to the left insular cortex.

CONCLUSION

Depressive mood might be correlated with the affective network, and disruptive behavior might be correlated with the DMN in adolescent depression.

Emotion-Dependent Functional Connectivity of the Default Mode Network in Adolescent Depression

BACKGROUND

Functional magnetic resonance imaging research suggests that major depressive disorder (MDD) in both adults and adolescents is marked by aberrant connectivity of the default mode network (DMN) during resting state. However, emotional dysregulation is also a key feature of MDD. No studies to date have examined emotion-related DMN pathology in adolescent depression. Comprehensively understanding the dynamics of DMN connectivity across brain states in individuals with depression with short disease histories could provide insight into the etiology of MDD.

METHODS

We collected functional magnetic resonance imaging data during an emotion identification task and during resting state from 26 medication-free adolescents (13-17 years old) with MDD and 37 well-matched healthy control subjects. We examined between-group differences in blood oxygenation level-dependent task responses and emotion-dependent and resting-state functional connectivity of the two primary nodes of the DMN: medial prefrontal cortex and posterior cingulate cortex (PCC). Additionally, we examined between-group differences in DMN functional connectivity and its relationship to depression severity and onset.

RESULTS

Relative to healthy control subjects, unmedicated adolescents with MDD demonstrated reduced medial prefrontal cortex and PCC emotion-related deactivation and greater medial prefrontal cortex and PCC emotion-dependent functional connectivity with precuneus, cingulate gyrus, and striatum/subcallosal cingulate gyrus. The PCC-subcallosal cingulate connectivity remained inflexibly elevated in the subjects with MDD versus healthy control subjects during resting state. Stronger PCC emotion-dependent functional connectivity was associated with greater depression severity and an earlier age of depression onset.

CONCLUSIONS

Adolescent depression is associated with inflexibly elevated DMN connections. Given more recent evidence of DMN maturation throughout adolescence, our findings suggest that early-onset depression adversely affects normal development of functional brain networks.

Altered functional interaction hub between affective network and cognitive control network in patients with major depressive disorder

Emotional and cognitive dysregulation in major depressive disorder (MDD) have been consistently considered to be attributed to structural and functional abnormalities in affective network (AN) and cognitive control network (CCN). This study was to investigate the functional connectivity (FC) patterns and altered functional interactions between both networks in MDD. We investigated resting-state functional connectivity magnetic resonance imaging in the AN and the CCN in 25 MDD and 35 healthy controls (HC). The seeds were from voxel-based morphometry (VBM) analysis results. Then FC within the AN was assessed from a seed placed in the left amygdala (AMG) and FC within CCN was determined by placing seeds in the right dorsolateral prefrontal cortex (DLPFC). Compared with HC, MDD showed reduced FC between left AMG and bilateral precuneus and right anterior cingulated cortex (ACC) within AN and reduced FC between right DLPFC and left cuneus, left lingual gyrus, and right ACC within CCN. An interaction hub of altered FC in MDD between AN and CCN located in the right ACC. Interestingly, the altered FC between right ACC and left AMG was negatively correlated with depressive symptom score while the altered FC between right ACC and DLPFC was positively correlated the executive function in MDD. The right ACC not only supports the cognitive and emotional processes, but also is an altered functional interaction hub between AN and CCN in MDD. It further suggest multiple sources of dysregulation in AN and CCN implicate both top-down cognitive control and bottom-up emotional expression dysfunction in MDD.

Emotion Awareness Predicts Body Mass Index Percentile Trajectories in Youth

OBJECTIVE

To examine the rate of change in body mass index (BMI) percentile across 3 years in relation to emotion identification ability and brain-based reactivity in emotional processing regions.

STUDY DESIGN

A longitudinal sample of 202 youths completed 3 functional magnetic resonance imaging-based facial processing tasks and behavioral emotion differentiation tasks. We examined the rate of change in the youth's BMI percentile as a function of reactivity in emotional processing brain regions and behavioral emotion identification tasks using multilevel modeling.

RESULTS

Lower correct identification of both happiness and sadness measured behaviorally predicted increases in BMI percentile across development, whereas higher correct identification of both happiness and sadness predicted decreases in BMI percentile, while controlling for children's pubertal status, sex, ethnicity, IQ score, exposure to antipsychotic medication, family income-to-needs ratio, and externalizing, internalizing, and depressive symptoms. Greater neural activation in emotional reactivity regions to sad faces also predicted increases in BMI percentile during development, also controlling for the aforementioned covariates.

CONCLUSION

Our findings provide longitudinal developmental data demonstrating links between both emotion identification ability and greater neural reactivity in emotional processing regions with trajectories of BMI percentiles across childhood.

Brain-behavior relationships in the experience and regulation of negative emotion in healthy children: implications for risk for childhood depression

Structural and functional alterations in a variety of brain regions have been associated with depression and risk for depression across the life span. A majority of these regions are associated with emotion reactivity and/or regulation. However, it is generally unclear what mechanistic role these alterations play in the etiology of depression. A first step toward understanding this is to characterize the relationships between variation in brain structure/function and individual differences in depression severity and related processes, particularly emotion regulation. To this end, the current study examines how brain structure and function predict concurrent and longitudinal measures of depression symptomology and emotion regulation skills in psychiatrically healthy school-age children (N = 60). Specifically, we found that smaller hippocampus volumes and greater responses to sad faces in emotion reactivity regions predict increased depressive symptoms at the time of scan, whereas larger amygdala volumes, smaller insula volumes, and greater responses in emotion reactivity regions predict decreased emotion regulation skills. In addition, larger insula volumes predict improvements in emotion regulation skills even after accounting for emotion regulation at the time of scan. Understanding brain-behavior relationships in psychiatrically healthy samples, especially early in development, will help inform normative developmental trajectories and neural alterations in depression and other affective pathology.

Cognitive impairment after chemotherapy related to atypical network architecture for executive control

OBJECTIVES

A common complaint of cancer patients is the experience of cognitive difficulty during and after chemotherapy. We hypothesized that cognitive impairment may result from dysfunction in large-scale brain networks, particularly those involved in attentional control.

METHODS

Using a case-control design, this study includes women with a history of invasive ductal or lobular triple-negative breast cancer who completed standard adjuvant chemotherapy within 2 years of study entry. Women who reported cognitive impairment by the Global Rating of Cognition question were considered to be cases (n = 15). Women who reported no cognitive impairment were considered to be controls (n = 13). All enrolled participants were eligible for MRI investigation and underwent resting-state functional connectivity MRI.

RESULTS

Women who self-reported cognitive impairment were found to have disrupted resting-state functional connectivity, as measured by MRI, when compared to women who did not self-report cognitive impairment. These findings suggest that some women may be more sensitive to the standard treatments for breast cancer and that this increased sensitivity may result in functional connectivity alterations in the brain networks supporting attention and executive function.

CONCLUSIONS

Neuroimaging analyses confirmed self-reported cognitive deficits in women with breast cancer treated with chemotherapy.

Decreased amygdala-insula resting state connectivity in behaviorally and emotionally dysregulated youth

The Research Domain Criteria (RDoC) adopts a dimensional approach for examining pathophysiological processes underlying categorically defined psychiatric diagnoses. We used this framework to examine relationships among symptom dimensions, diagnostic categories, and resting state connectivity in behaviorally and emotionally dysregulated youth selected from the Longitudinal Assessment of Manic Symptoms study (n=42) and healthy control youth (n=18). Region of interest analyses examined relationships among resting state connectivity, symptom dimensions (behavioral and emotional dysregulation measured with the Parent General Behavior Inventory-10 Item Mania Scale [PGBI-10M]; dimensional severity measures of mania, depression, anxiety), and diagnostic categories (Bipolar Spectrum Disorders, Attention Deficit Hyperactivity Disorder, Anxiety Disorders, and Disruptive Behavior Disorders). After adjusting for demographic variables, two dimensional measures showed significant inverse relationships with resting state connectivity, regardless of diagnosis: 1) PGBI-10M with amygdala-left posterior insula/bilateral putamen; and 2) depressive symptoms with amygdala-right posterior insula connectivity. Diagnostic categories showed no significant relationships with resting state connectivity. Resting state connectivity between amygdala and posterior insula decreased with increasing severity of behavioral and emotional dysregulation and depression; this suggests an intrinsic functional uncoupling of key neural regions supporting emotion processing and regulation. These findings support the RDoC dimensional approach for characterizing pathophysiologic processes that cut across different psychiatric disorders.

Anterior insula volume and guilt: neurobehavioral markers of recurrence after early childhood major depressive disorder

IMPORTANCE

This is the first study to date to examine volumetric alterations in the anterior insula (AI) as a potential biomarker for the course of childhood major depressive disorder (MDD).

OBJECTIVES

To examine whether children with a history of preschool-onset (PO) MDD show reduced AI volume, whether a specific symptom of PO MDD (pathological guilt) is related to AI volume reduction (given the known relationship between AI and guilt processing), and whether AI volumes predict subsequent likelihood of having an episode of MDD.

DESIGN, SETTING, AND PARTICIPANTS

In a prospective longitudinal study, 306 children (age range, 3.00-5.11 years) and caregivers completed DSM diagnostic assessments at 6 annual time points during 10 years as part of the Preschool Depression Study. Magnetic resonance imaging was completed on a subset of 145 school-age children (age range, 6.11-12.11 years).

MAIN OUTCOMES AND MEASURES

Whole-brain-adjusted AI volume measured using magnetic resonance imaging at school age and children's diagnosis of MDD any time after their imaging.

RESULTS

Compared with children without a history of PO MDD, school-age children previously diagnosed as having PO MDD had smaller left and right AI volumes (Wilks Λ = 0.94, F2,124 = 3.37, P = .04, Cohen d = 0.23). However, the effect of PO MDD on reduced AI volumes was better explained by children's experience of pathological guilt during preschool (Λ = 0.91, F2,120 = 6.17, P = .003, d = .30). When covarying for children's lifetime history of MDD episodes, their experience of pathological guilt during preschool, as well as their sex and age at the time of imaging, schoolchildren's right-side AI volume was a significant predictor of being diagnosed as having an MDD episode after imaging (odds ratio, 0.96; 95% CI, 0.01-0.75; P = .03).

CONCLUSIONS AND RELEVANCE

These results provide evidence that structural abnormalities in AI volume are related to the neurobiology of depressive disorders starting in early childhood. The present findings are consistent with mounting research in adult MDD suggesting that insula function and structure may be a target biomarker for major depression.

Aberrant resting-state functional connectivity in limbic and salience networks in treatment--naïve clinically depressed adolescents

BACKGROUND

Depression is prevalent and typically has its onset in adolescence. Resting-state fMRI could help create a better understanding of the underlying neurobiological mechanisms during this critical period. In this study, resting-state functional connectivity (RSFC) is examined using seed regions-of-interest (ROIs) associated with three networks: the limbic network, the default mode network (DMN) and the salience network.

METHODS

Twenty-six treatment-naïve, clinically depressed adolescents of whom 18 had comorbid anxiety, and 26 pair-wise matched healthy controls underwent resting-state fMRI. The three networks were investigated using a seed-based ROI approach with seeds in the bilateral amygdala (limbic network), bilateral dorsal anterior cingulate cortex (dACC; salience network) and bilateral posterior cingulate cortex (default mode network).

RESULTS

Compared to healthy controls, clinically depressed adolescents showed increased RSFC of the left amygdala with right parietal cortical areas, and decreased right amygdala RSFC with left frontal cortical areas including the ACC, as well as with right occipito-parietal areas. The bilateral dACC showed decreased RSFC with the right middle frontal gyrus, frontal pole, and inferior frontal gyrus in clinically depressed adolescents. No abnormalities in DMN RSFC were found, and differences in RSFC did not correlate with clinical measures.

CONCLUSIONS

The aberrant RSFC of the amygdala network and the dACC network may be related to altered emotion processing and regulation in depressed adolescents. Our results provide new insights into RSFC in clinically depressed adolescents and future models on adolescent depression may include abnormalities in the connectivity of salience network.

Abnormal amygdala resting-state functional connectivity in adolescent depression

IMPORTANCE

Major depressive disorder (MDD) frequently emerges during adolescence and can lead to persistent illness, disability, and suicide. The maturational changes that take place in the brain during adolescence underscore the importance of examining neurobiological mechanisms during this time of early illness. However, neural mechanisms of depression in adolescents have been understudied. Research has implicated the amygdala in emotion processing in mood disorders, and adult depression studies have suggested amygdala-frontal connectivity deficits. Resting-state functional magnetic resonance imaging is an advanced tool that can be used to probe neural networks and identify brain-behavior relationships.

OBJECTIVE

To examine amygdala resting-state functional connectivity (RSFC) in adolescents with and without MDD using resting-state functional magnetic resonance imaging as well as how amygdala RSFC relates to a broad range of symptom dimensions.

DESIGN, SETTING, AND PARTICIPANTS

A cross-sectional resting-state functional magnetic resonance imaging study was conducted within a depression research program at an academic medical center. Participants included 41 adolescents and young adults aged 12 to 19 years with MDD and 29 healthy adolescents (frequency matched on age and sex) with no psychiatric diagnoses.

MAIN OUTCOMES AND MEASURES

Using a whole-brain functional connectivity approach, we examined the correlation of spontaneous fluctuation of the blood oxygen level-dependent signal of each voxel in the whole brain with that of the amygdala.

RESULTS

Adolescents with MDD showed lower positive RSFC between the amygdala and hippocampus, parahippocampus, and brainstem (z >2.3, corrected P < .05); this connectivity was inversely correlated with general depression (R = -.523, P = .01), dysphoria (R = -.455, P = .05), and lassitude (R = -.449, P = .05) and was positively correlated with well-being (R = .470, P = .03). Patients also demonstrated greater (positive) amygdala-precuneus RSFC (z >2.3, corrected P < .05) in contrast to negative amygdala-precuneus RSFC in the adolescents serving as controls.

CONCLUSIONS AND RELEVANCE

Impaired amygdala-hippocampal/brainstem and amygdala-precuneus RSFC have not previously been highlighted in depression and may be unique to adolescent MDD. These circuits are important for different aspects of memory and self-processing and for modulation of physiologic responses to emotion. The findings suggest potential mechanisms underlying both mood and vegetative symptoms, potentially via impaired processing of memories and visceral signals that spontaneously arise during rest, contributing to the persistent symptoms experienced by adolescents with depression.

Developmental Resting State Functional Connectivity for Clinicians

Resting state functional magnetic imaging (fMRI) is a novel means to examine functional brain networks. It allows investigators to identify functional networks defined by distinct, spontaneous signal fluctuations. Resting state functional connectivity (RSFC) studies examining child and adolescent psychiatric disorders are being published with increasing frequency, despite concerns about the impact of motion on findings. Here we review important RSFC findings on typical brain development and recent publications of child and adolescent psychiatric disorders. We close with a summary of the major findings and current strengths and limitations of RSFC studies.

Practitioner review: Dysphoria and its regulation in child and adolescent depression

BACKGROUND

By emphasizing the importance of emotions, the 'affect revolution' in how human behavior is conceptualized has inspired a new generation of studies on dysphoric experience and its regulation in clinical depression, and novel efforts to characterize the precursors of affective disorders in juveniles at familial risk for depression.

METHOD

We review clinical, behavioral, and functional neuroimaging studies of dysphoric experience and its regulation in depressed children and adolescents, and in juvenile offspring of parents with histories of clinical depression. We discuss the implication of the literature in the context of maternal depression.

RESULTS

Findings confirm the high rate of clinically significant dysphoria in depressed children and adolescents and reveal notable affective lability in daily life as a function of context and activity. Findings also show that depressed youngsters have problems in attenuating dysphoria. Similarly, never-depressed offspring at familial risk for depression display problems in mood repair and impaired mood repair mechanisms. Brain neuroimaging findings indicate that, overall, depressed, and high-risk youngsters differ from never depressed controls in neural functioning (activation, connectivity) both at rest and in response to emotion triggers.

CONCLUSION

The evaluation of depressed youngsters should include questions about reactivity of dysphoric mood to the changing contexts of daily life and about how they manage (respond to) their own sadness and distress. The resultant information may help the clinician to restructure a young patient's day for the better and identify helpful mood repair responses. Evidence of impaired mood repair mechanisms in youngsters at high-risk for depression suggests the need for early intervention. But interventions must consider that many depressed and high-risk children have depressed mothers, who may be constrained in their ability to help offspring's emotion regulation efforts. To optimize treatment response of offspring, mothers of depressed children should therefore be routinely screened for depression and treated, as warranted.

Functional connectivity of negative emotional processing in adolescent depression

BACKGROUND

The subgenual anterior cingulate cortex (sgACC) and its connected circuitry have been heavily implicated in emotional functioning in adolescent-onset major depressive disorder (MDD). While several recent studies have examined sgACC functional connectivity (FC) in depressed youth at rest, no studies to date have investigated sgACC FC in adolescent depression during negative emotional processing.

METHODS

Nineteen medication-naïve adolescents with MDD and 19 matched healthy controls (HCL) performed an implicit fear facial affect recognition task during functional magnetic resonance imaging (fMRI). We defined seeds in bilateral sgACC and assessed FC using the psychophysiological interaction method. We also applied cognitive behavioral modeling to estimate group differences in perceptual sensitivity in this task. Finally, we correlated connectivity strength with clinical data and perceptual sensitivity.

RESULTS

Depressed adolescents showed increased sgACC-amygdala FC and decreased sgACC-fusiform gyrus, sgACC-precuneus, sgACC-insula, and sgACC-middle frontal gyrus FC compared to HCL (p<0.05, corrected). Among the MDD, sgACC-precuneus FC negatively correlated with depression severity (p<0.05, corrected). Lastly, MDD adolescents exhibited poorer perceptual sensitivity in the task than HCL, and individual differences in perceptual sensitivity significantly correlated with sgACC FC and depression scores (p<0.05, corrected).

LIMITATIONS

Subjects were clinically homogenous, possibly limiting generalizability of the findings.

CONCLUSIONS

Adolescent depression is associated with biased processing of negative stimuli that may be driven by sgACC dysregulation and may possibly lead to an imbalance among intrinsic functional brain networks. This work also establishes the use of combining neuroimaging and cognitive behavioral modeling methods to investigate cognitive and neural differences between psychiatric and healthy populations.

Understanding Familial Risk for Depression: A 25-Year Perspective

Major depressive disorder (MDD) is among the most prevalent, debilitating, and costly of all illnesses worldwide. Investigators have made considerable progress in elucidating psychological and biological correlates of MDD; however, far less is known about factors that are implicated in risk for depression. Given the high risk for MDD associated with a family history of depression, investigators have worked to understand both the effects of parental depression on offspring and the mechanisms that might underlie familial risk for MDD. In this article, we describe the evolution of investigators' understanding of the psychobiological functioning of children of depressed parents, and we present recent findings concerning cognitive and neural aspects of risk for MDD using our high-risk sample as a context and foundation for this discussion. We integrate these data in a conceptualization of mechanisms underlying risk for depression, focusing on the constructs of emotion dysregulation and stress reactivity. Recognizing the 25-year anniversary of the Association for Psychological Science, we place this presentation in the context of the past 25 years of research on depression. We conclude by discussing the significance of emotion dysregulation and stress reactivity for studying risk for depression, for developing approaches to prevent MDD, and for moving theory and research in this field forward.

A translational neuroscience framework for the development of socioemotional functioning in health and psychopathology

The development of socioemotional functioning is a complex process that occurs over a protracted time period and requires coordinating affective, cognitive, and social faculties. At many points in development, the trajectory of socioemotional development can be deleteriously altered due to a combination of environmental insults and individual vulnerabilities. The result can be psychopathology. However, researchers are just beginning to understand the neural and genetic mechanisms involved in the development of healthy and disordered socioemotional functioning. We propose a translational developmental neuroscience framework to understand the transactional process that results in socioemotional functioning in both healthy and disordered populations. We then apply this framework to healthy socioemotional development, pediatric anxiety, pediatric depression, and autism spectrum disorder, selectively reviewing current literature in light of the framework. Finally, we examine ways that the framework can help to frame future directions of research on socioemotional development and translational implications for intervention.

Resting state FMRI research in child psychiatric disorders

Concurring with the shift from linking functions to specific brain areas towards studying network integration, resting state FMRI (R-FMRI) has become an important tool for delineating the functional network architecture of the brain. Fueled by straightforward data collection, R-FMRI analysis methods as well as studies reporting on R-FMRI have flourished, and already impact research on child- and adolescent psychiatric disorders. Here, we review R-FMRI analysis techniques and outline current methodological debates. Furthermore, we provide an overview of the main R-FMRI findings related to child- and adolescent psychiatric disorders. R-FMRI research has contributed significantly to our understanding of brain function in child and adolescent psychiatry: existing hypotheses based on task-based FMRI were confirmed and new insights into the brain's functional architecture of disorders were established. However, results were not always consistent. While resting state networks are robust and reproducible, neuroimaging research in psychiatric disorders is especially complicated by tremendous phenotypic heterogeneity. It is imperative that we overcome this heterogeneity when integrating neuroimaging into the diagnostic and treatment process. As R-FMRI allows investigating the richness of the human functional connectome and can be easily collected and aggregated into large-scale datasets, it is clear that R-FMRI can be a powerful tool in our quest to understand psychiatric pathology.

Resting state functional connectivity of the ventral attention network in children with a history of depression or anxiety

OBJECTIVE

We examined whether depression and anxiety disorders in early childhood were associated with changes in resting state functional connectivity (RSFC) of the ventral attention network (VAN), and whether RSFC in the VAN was associated with alterations in attention specific to these disorders. Important clinical features of these illnesses, including changes in attention toward novel stimuli and changes in attention to stimuli of negative valence (threat/sad bias), indirectly implicate the VAN.

METHOD

We collected resting state functional magnetic resonance imaging data in children aged 8 to 12 years. Data were volume censored to reduce artifact from submillimeter movement, resulting in analyzable data from 30 children with a history of depression and/or anxiety and 42 children with no psychiatric history. We compared pairwise RSFC among the following VAN regions: right ventro-lateral prefrontal cortex (VLPFC), right posterior superior temporal gyrus (pSTG), and right ventral supramarginal gyrus (vSMG). We also collected measures of threat bias and current clinical symptoms.

RESULTS

Children with a history of depression and/or anxiety had reduced RSFC among the regions of the VAN compared to children with no psychiatric history. The magnitude of VAN RSFC was correlated with measures of attention bias toward threat but not with current depressive, internalizing, or externalizing symptoms. No RSFC changes were detected between groups among homotopic left hemisphere regions.

CONCLUSIONS

Disruption in the VAN may be an early feature of depression and anxiety disorders. VAN changes were associated with attention bias and clinical history but not with current symptoms of depression and anxiety.

Abnormal functional connectivity of amygdala in late-onset depression was associated with cognitive deficits

BACKGROUND

Major depressive disorder (MDD) is associated with decreased function of cortico-limbic circuits, which play important roles in the pathogenesis of MDD. Abnormal functional connectivity (FC) with the amygdala, which is involved in cortico-limbic circuits, has also been observed in MDD. However, little is known about connectivity alterations in late-onset depression (LOD) or whether disrupted connectivity is correlated with cognitive impairment in LOD.

METHODS AND RESULTS

A total of twenty-two LOD patients and twenty-two matched healthy controls (HC) underwent neuropsychological tests and resting state functional magnetic resonance imaging (rs-fMRI). Regional homogeneity (ReHo) and FC with bilateral amygdala seeds were used to analyze blood oxygen level-dependent fMRI data between two groups. Compared with HC, LOD patients showed decreased ReHo in the right middle frontal gyrus and left superior frontal gyrus. In the LOD group, the left amygdala had decreased FC with the right middle frontal gyrus and the left superior frontal gyrus in the amygdala positive network, and it had increased FC with the right post-central gyrus in the amygdala negative network. However, significantly reduced FC with the right amygdala was observed in the right middle occipital gyrus in the amygdala negative network. Further correlative analyses revealed that decreased FC between the amygdala and the right middle occipital gyrus was negatively correlated with the verbal fluency test (VFT, r = -0.485, P = 0.022) and the digit span test (DST, r = -0.561, P = 0.007).

CONCLUSIONS

Our findings of reduced activity of the prefrontal gyrus and abnormal FC with the bilateral amygdala may be key markers of cognitive dysfunction in LOD patients.

Structural-functional correlations between hippocampal volume and cortico-limbic emotional responses in depressed children

Although hippocampal atrophy and altered functional brain responses to emotional stimuli have been found in major depressive disorder (MDD), the relationship between the two is not yet well understood. The present study focused on children with and without a history of preschool onset MDD (PO-MDD) and directly examined the relations between hippocampal volume and functional brain activation to affect-eliciting stimuli. Children completed annual diagnostic assessments starting at preschool. When children were school-aged, high-resolution structural MRI and task-related functional MRI data were acquired from N = 64 nonmedicated children. During fMRI, subjects were shown emotional faces. Results from the total sample indicated that smaller bilateral hippocampal volumes were associated with greater cortico-limbic (e.g., amygdala, hippocampus, dorsolateral prefrontal cortex) activation to sad or negative faces versus neutral faces. Left hippocampal volume was negatively associated with the cortico-limbic activation in both the PO-MDD and healthy children. Right hippocampal volume was negatively correlated with amygdala responses in the PO-MDD group, but not in the healthy comparison group. These findings suggest that there may be important interrelationships between reduced hippocampal volume and hyperactivation of brain responses in children, both those with and those without a history of PO-MDD.

Treatment of anxiety and depression in the preschool period

OBJECTIVE

Empirical studies have established that clinical anxiety and depressive disorders may arise in preschool children as young as 3.0 years. Because empirical studies validating and characterizing these disorders in preschoolers are relatively recent, less work has been done on the development and testing of age-appropriate treatments.

METHOD

A comprehensive literature search yielded several small randomized controlled trials of psychotherapeutic treatments for preschool anxiety and depression. The literature also contained case series of behavioral and psychopharmacologic interventions for specific anxiety disorders. However, to date, no large-scale randomized controlled trials of treatment for any anxiety or depressive disorder specifically targeting preschool populations have been published.

RESULTS

Several age-adapted forms of cognitive-behavioral therapy have been developed and preliminarily tested in small randomized controlled trials and appear promising for different forms of preschool anxiety disorders. Notably, these adaptations centrally involve primary caregivers and use age-adjusted methodology such as cartoon-based materials and co-constructed drawing or narratives. Modified forms of parent child interaction therapy have been tested and appear promising for anxiety and depression. Although preventive interventions that target parenting have shown significant promise in anxiety, these methods have not been explored in early childhood depression. Studies of the impact of parental treatment on infants suggest that direct treatment of the youngest children may be necessary to affect long-term change.

CONCLUSIONS

Recommendations are made for the clinical treatment of these disorders when psychotherapy is the first line of intervention.

Evidence for a cerebral cortical thickness network anti-correlated with amygdalar volume in healthy youths: implications for the neural substrates of emotion regulation

Recent functional connectivity studies have demonstrated that, in resting humans, activity in a dorsally-situated neocortical network is inversely associated with activity in the amygdalae. Similarly, in human neuroimaging studies, aspects of emotion regulation have been associated with increased activity in dorsolateral, dorsomedial, orbital and ventromedial prefrontal regions, as well as concomitant decreases in amygdalar activity. These findings indicate the presence of two countervailing systems in the human brain that are reciprocally related: a dorsally-situated cognitive control network, and a ventrally-situated limbic network. We investigated the extent to which this functional reciprocity between limbic and dorsal neocortical regions is recapitulated from a purely structural standpoint. Specifically, we hypothesized that amygdalar volume would be related to cerebral cortical thickness in cortical regions implicated in aspects of emotion regulation. In 297 typically developing youths (162 females, 135 males; 572 MRIs), the relationship between cortical thickness and amygdalar volume was characterized. Amygdalar volume was found to be inversely associated with thickness in bilateral dorsolateral and dorsomedial prefrontal, inferior parietal, as well as bilateral orbital and ventromedial prefrontal cortices. Our findings are in line with previous work demonstrating that a predominantly dorsally-centered neocortical network is reciprocally related to core limbic structures such as the amygdalae. Future research may benefit from investigating the extent to which such cortical-limbic morphometric relations are qualified by the presence of mood and anxiety psychopathology.

Childhood depression: a systematic review

As an important public health issue, childhood depression deserves special attention, considering the serious and lasting consequences of the disease to child development. Taking this into consideration, the present study was based on the following question: what practical contributions to clinicians and researchers does the current literature on childhood depression have to offer? The objective of the present study was to conduct a systematic review of articles regarding childhood depression. To accomplish this purpose, a systematic review of articles on childhood depression, published from January 1, 2010 to November 24, 2012, on MEDLINE and SciELO databases was carried out. Search terms were "depression" (medical subject headings [MeSH]), "child" (MeSH), and "childhood depression" (keyword). Of the 180 retrieved studies, 25 met the eligibility criteria. Retrieved studies covered a wide range of aspects regarding childhood depression, such as diagnosis, treatment, prevention and prognosis. Recent scientific literature regarding childhood depression converge to, directly or indirectly, highlight the negative impacts of depressive disorders to the children's quality of life. Unfortunately, the retrieved studies show that childhood depression commonly grows in a background of vulnerability and poverty, where individual and familiar needs concerning childhood depression are not always taken into consideration. In this context, this review demonstrated that childhood-onset depression commonly leads to other psychiatric disorders and co-morbidities. Many of the retrieved studies also confirmed the hypothesis that human resources (eg, health care team in general) are not yet adequately trained to address childhood depression. Thus, further research on the development of programs to prepare health care professionals to deal with childhood depression is needed, as well as complementary studies, with larger and more homogeneous samples, centered on prevention and treatment of childhood depression.

Education and depression

This article is intended to assist educators in the medical field in promoting competency among medical students and trainees on the key issues in child and adolescent depression, including approach, understanding, and management. Using clinical vignettes, up-to-date research, and expert opinion and referencing accessible guidelines, resources, and tools, the authors' goal is to create information that is engaging and useful. It is designed to reach a broad audience with emphasis on trainees who are early in their career path (eg, medical students or interns) and/or who are going into primary care.

Anomalous functional brain activation following negative mood induction in children with pre-school onset major depression

While major depressive disorder has been shown to be a significant mental health issue for school-age children, recent research indicates that depression can be observed in children as early as the preschool period. Yet, little work has been done to explore the neurobiological factors associated with this early form of depression. Given research suggesting a relation between adult depression and anomalies in emotion-related neural circuitry, the goal of the current study was to elucidate changes in functional activation during negative mood induction and emotion regulation in school-age children with a history of preschool-onset depression. The results suggest that a history of depression during the preschool period is associated with decreased activity in prefrontal cortex during mood induction and regulation. Moreover, the severity of current depressed mood was associated with increased activity in limbic regions, such as the amygdala, particularly in children with a history of depression. Similar to results observed in adult depression, the current findings indicate disruptions in emotion-related neural circuitry associated with preschool-onset depression.