Cortical thickness predicts the first onset of major depression in adolescence
INTERNATIONAL JOURNAL OF DEVELOPMENTAL NEUROSCIENCE
2015; 46: 125-131
Given the increasing prevalence of Major Depressive Disorder and recent advances in preventative treatments for this disorder, an important challenge in pediatric neuroimaging is the early identification of individuals at risk for depression. We examined whether machine learning can be used to predict the onset of depression at the individual level. Thirty-three never-disordered adolescents (10-15 years old) underwent structural MRI. Participants were followed for 5 years to monitor the emergence of clinically significant depressive symptoms. We used support vector machines (SVMs) to test whether baseline cortical thickness could reliably distinguish adolescents who develop depression from adolescents who remained free of any Axis I disorder. Accuracies from subsampled cross-validated classification were used to assess classifier performance. Baseline cortical thickness correctly predicted the future onset of depression with an overall accuracy of 70% (69% sensitivity, 70% specificity; p=0.021). Examination of SVM feature weights indicated that the right medial orbitofrontal, right precentral, left anterior cingulate, and bilateral insular cortex contributed most strongly to this classification. These findings indicate that cortical gray matter structure can predict the subsequent onset of depression. An important direction for future research is to elucidate mechanisms by which these anomalies in gray matter structure increase risk for developing this disorder.
View details for DOI 10.1016/j.ijdevneu.2015.07.007
View details for Web of Science ID 000362139500018
View details for PubMedID 26315399
Neural markers of familial risk for depression: An investigation of cortical thickness abnormalities in healthy adolescent daughters of mothers with recurrent depression.
Journal of abnormal psychology
2015; 124 (3): 476-485
Having a mother with major depressive disorder (MDD) is one of the strongest predictors of depression in late adolescence and early adulthood. Despite this fact, we know little about the neural mechanisms involved in the intergenerational transmission of risk for depression. Twenty-eight never-disordered daughters of recurrent depressed mothers (high-risk) and 36 never-disordered daughters of never-depressed mothers (low-risk) were scanned using MRI. Scan data were processed to provide measurements of cortical gray matter thickness. A general linear model was conducted at each surface point to assess the main effect of familial risk on cortical structure as well as to explore the interaction of familial risk and age. High-risk girls exhibited significantly thinner cortical gray matter in the right fusiform gyrus relative to low-risk girls. Exploratory analyses indicated interactions of risk group and age in the bilateral anterior insula and right anterior cingulate cortex (ACC); whereas low-risk girls exhibited an inverse association between age and thickness, girls at high risk for depression showed the reverse pattern. Additional exploratory analyses, using scores on the Children's Sadness Management Scale, indicated that thinner gray matter in the ACC of high-risk girls was associated with greater difficulty in managing sadness. These findings indicate that anomalous reductions in the cortical thickness of the fusiform gyrus may be a marker of risk for MDD. The interaction of age and group for gray matter thickness of the insula and ACC suggests a particularly important role for these regions in risk for depression and warrants additional research in longitudinal studies. (PsycINFO Database Record
View details for DOI 10.1037/abn0000050
View details for PubMedID 25894441
- Neural Markers of Familial Risk for Depression: An Investigation of Cortical Thickness Abnormalities in Healthy Adolescent Daughters of Mothers With Recurrent Depression JOURNAL OF ABNORMAL PSYCHOLOGY 2015; 124 (3): 476-485
Telomere length and cortisol reactivity in children of depressed mothers
2015; 20 (5): 615-620
A growing body of research demonstrates that individuals diagnosed with major depressive disorder (MDD) are characterized by shortened telomere length, which has been posited to underlie the association between depression and increased instances of medical illness. The temporal nature of the relation between MDD and shortened telomere length, however, is not clear. Importantly, both MDD and telomere length have been associated independently with high levels of stress, implicating dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis and anomalous levels of cortisol secretion in this relation. Despite these associations, no study has assessed telomere length or its relation with HPA-axis activity in individuals at risk for depression, before the onset of disorder. In the present study, we assessed cortisol levels in response to a laboratory stressor and telomere length in 97 healthy young daughters of mothers either with recurrent episodes of depression (i.e., daughters at familial risk for depression) or with no history of psychopathology. We found that daughters of depressed mothers had shorter telomeres than did daughters of never-depressed mothers and, further, that shorter telomeres were associated with greater cortisol reactivity to stress. This study is the first to demonstrate that children at familial risk of developing MDD are characterized by accelerated biological aging, operationalized as shortened telomere length, before they had experienced an onset of depression; this may predispose them to develop not only MDD but also other age-related medical illnesses. It is critical, therefore, that we attempt to identify and distinguish genetic and environmental mechanisms that contribute to telomere shortening.
View details for DOI 10.1038/mp.2014.119
View details for Web of Science ID 000353706400012
View details for PubMedID 25266121
Concordance of mother-daughter diurnal cortisol production: Understanding the intergenerational transmission of risk for depression
2015; 108: 98-104
A growing body of research is demonstrating concordance between mother and child diurnal cortisol production. In the context of maternal history of depression, intergenerational concordance of cortisol production could contribute to hypercortisolemia in children of depressed mothers, which has been shown to increase risk for MDD. The current study is the first to examine concordance in diurnal cortisol production between mothers with a history of depression and their never-depressed, but high-risk, children. We collected salivary cortisol across 2 days from mothers with (remitted; RMD) and without (CTL) a history of recurrent episodes of depression and their never-depressed daughters. As expected, RMD mothers and their daughters both exhibited higher cortisol production than did their CTL counterparts. Moreover, both across and within groups, mothers' and daughters' cortisol production were directly coupled. These findings suggest that there is an intergenerational concordance in cortisol dysregulation that may contribute to hypercortisolemia in girls at familial risk for depression.
View details for DOI 10.1016/j.biopsycho.2015.03.019
View details for Web of Science ID 000353996100011
View details for PubMedID 25862380
HPA-axis reactivity interacts with stage of pubertal development to predict the onset of depression
2015; 55: 94-101
Both elevated and blunted levels of cortisol secretion during childhood and adolescence have been linked to the subsequent onset of major depressive disorder (MDD). These mixed findings may be due to developmental changes in HPA-axis functioning, which have not been previously assessed in the context of risk. In the present study, therefore, we examined whether pubertal development moderated the influence of cortisol secretion on the subsequent development of MDD. Eighty-nine never-disordered girls ages 9-15 years, many of whom were at high risk for depression by virtue of having a maternal history of the disorder, completed a laboratory stress task. To index cortisol reactivity, salivary cortisol samples were collected at baseline and 15min following the onset of the stressor. Girls' levels of pubertal development were measured using Tanner staging. All participants were followed through age 18 in order to assess the subsequent development of MDD. Pubertal stage moderated the effects of cortisol stress reactivity on the development of MDD. Specifically, the onset of MDD was predicted by cortisol hyporeactivity in girls who were earlier in pubertal development (Tanner stage≤2), but by cortisol hyperreactivity in girls who were later in pubertal development (Tanner stage≥3.5).These findings demonstrate that girls' cortisol stress reactivity predicts the subsequent onset of MDD, and further, that the nature of this effect depends on the girls' level of pubertal development. Results are discussed in the context of clarifying previous findings, and directions for future research are offered.
View details for DOI 10.1016/j.psyneuen.2015.02.004
View details for Web of Science ID 000353090100009
View details for PubMedID 25745954
Identification of a direct GABAergic pallidocortical pathway in rodents
EUROPEAN JOURNAL OF NEUROSCIENCE
2015; 41 (6): 748-759
Interaction between the basal ganglia and the cortex plays a critical role in a range of behaviors. Output from the basal ganglia to the cortex is thought to be relayed through the thalamus, but an intriguing alternative is that the basal ganglia may directly project to and communicate with the cortex. We explored an efferent projection from the globus pallidus externa (GPe), a key hub in the basal ganglia system, to the cortex of rats and mice. Anterograde and retrograde tracing revealed projections to the frontal premotor cortex, especially the deep projecting layers, originating from GPe neurons that receive axonal inputs from the dorsal striatum. Cre-dependent anterograde tracing in Vgat-ires-cre mice confirmed that the pallidocortical projection is GABAergic, and in vitro optogenetic stimulation in the cortex of these projections produced a fast inhibitory postsynaptic current in targeted cells that was abolished by bicuculline. The pallidocortical projections targeted GABAergic interneurons and, to a lesser extent, pyramidal neurons. This GABAergic pallidocortical pathway directly links the basal ganglia and cortex, and may play a key role in behavior and cognition in normal and disease states.
View details for DOI 10.1111/ejn.12822
View details for Web of Science ID 000351439000002
Support vector machine classification of major depressive disorder using diffusion-weighted neuroimaging and graph theory.
Frontiers in psychiatry
2015; 6: 21-?
Recently, there has been considerable interest in understanding brain networks in major depressive disorder (MDD). Neural pathways can be tracked in the living brain using diffusion-weighted imaging (DWI); graph theory can then be used to study properties of the resulting fiber networks. To date, global abnormalities have not been reported in tractography-based graph metrics in MDD, so we used a machine learning approach based on "support vector machines" to differentiate depressed from healthy individuals based on multiple brain network properties. We also assessed how important specific graph metrics were for this differentiation. Finally, we conducted a local graph analysis to identify abnormal connectivity at specific nodes of the network. We were able to classify depression using whole-brain graph metrics. Small-worldness was the most useful graph metric for classification. The right pars orbitalis, right inferior parietal cortex, and left rostral anterior cingulate all showed abnormal network connectivity in MDD. This is the first use of structural global graph metrics to classify depressed individuals. These findings highlight the importance of future research to understand network properties in depression across imaging modalities, improve classification results, and relate network alterations to psychiatric symptoms, medication, and comorbidities.
View details for DOI 10.3389/fpsyt.2015.00021
View details for PubMedID 25762941
Coping with having a depressed mother: the role of stress and coping in hypothalamic-pituitary-adrenal axis dysfunction in girls at familial risk for major depression.
Development and psychopathology
2014; 26 (4): 1401-1409
Having a depressed mother is one of the strongest predictors of depression in adolescence. We investigated whether the stress of having a mother with recurrent depression is associated with dysfunction in adolescents in the HPA axis and whether the tendency to use involuntary coping strategies in dealing with this stress is associated with exacerbation of dysfunction in this system. Sixty-four never-disordered daughters of mothers with recurrent depression (high risk) and 64 never-disordered daughters of never-disordered mothers (low risk) completed diurnal cortisol and stress assessments. High-risk girls secreted more diurnal cortisol than did low-risk girls. Whereas low-risk girls secreted higher levels of cortisol with increasing stress associated with having a depressed mother, no such relation was present in high-risk girls. Finally, in contrast to low-risk girls, girls at familial risk for depression who more frequently used involuntary versus voluntary coping exhibited the greatest elevations in diurnal cortisol. These findings indicate that a tendency to utilize involuntary, as opposed to voluntary, coping strategies in dealing with stress involving maternal depression exacerbates already high levels of cortisol in youth at risk for depression. Future research that examines whether interventions aimed at increasing the use of voluntary coping strategies normalizes HPA axis dysfunction is of interest.
View details for DOI 10.1017/S0954579414001102
View details for PubMedID 25422969
- Coping with having a depressed mother: The role of stress and coping in hypothalamic-pituitary-adrenal axis dysfunction in girls at familial risk for major depression DEVELOPMENT AND PSYCHOPATHOLOGY 2014; 26 (4): 1401-1409
- Recalling happy memories in remitted depression: A neuroimaging investigation of the repair of sad mood COGNITIVE AFFECTIVE & BEHAVIORAL NEUROSCIENCE 2014; 14 (2): 818-826
Recalling happy memories in remitted depression: a neuroimaging investigation of the repair of sad mood.
Cognitive, affective & behavioral neuroscience
2014; 14 (2): 818-826
Major depressive disorder (MDD) is a recurrent mood disorder. The high rate of recurrence of MDD suggests the presence of stable vulnerability factors that place individuals with a history of major depression at an increased risk for the onset of another episode. Previous research has linked the remitted state, and therefore increased vulnerability for depressive relapse, with difficulties in the use of pleasant autobiographical memories to repair sad mood. In the present study, we examined the neural correlates of these difficulties. Groups of 16 currently euthymic, remitted depressed individuals and 16 healthy (control) women underwent functional magnetic resonance imaging (fMRI) during sad mood induction and during recovery from a sad mood state through recall of mood-incongruent positive autobiographical memories. Sad mood was induced in participants by using film clips; participants then recalled positive autobiographical memories, a procedure previously shown to repair negative affect. During both the sad mood induction and automatic mood regulation, control participants exhibited activation in the left ventrolateral prefrontal cortex (vlPFC) and cuneus; in contrast, remitted participants exhibited a decrease in activation in these regions. Furthermore, exploratory analyses revealed that reduced activation levels during mood regulation predicted a worsening of depressive symptoms at a 20-month follow-up assessment. These findings highlight a dynamic role of the vlPFC and cuneus in the experience and modulation of emotional states and suggest that functional anomalies of these brain regions are associated with a history of, and vulnerability to, depression.
View details for DOI 10.3758/s13415-013-0216-0
View details for PubMedID 24146315
Activation of the medial prefrontal and posterior cingulate cortex during encoding of negative material predicts symptom worsening in major depression
2014; 25 (5): 324-329
Considerable research indicates that depressed individuals have better memory for negative material than do nondepressed individuals, and that this bias is associated with differential patterns of neural activation. It is not known, however, whether these aberrant activation patterns predict illness course. Using functional neuroimaging, we examined whether change in depressive symptoms is predicted by baseline patterns of neural activation that underlie negative memory biases in major depressive disorder. Depressed participants viewed negative and neutral pictures during functional MRI at baseline and completed an incidental memory task for these pictures 1 week later. Depression severity was assessed by administering the Beck Depression Inventory both at baseline (Time 1) and at Time 2, an average of 18 months later. Contrast maps of activation for subsequently remembered negative versus subsequently remembered neutral pictures were regressed against change in Beck Depression Inventory scores between Time 1 and Time 2, controlling for initial symptom severity. Results from this analysis revealed no associations between memory sensitivity for negative stimuli and symptom change. In contrast, whole brain analyses revealed significant positive associations between within-subject changes in depressive symptoms and baseline neural activation to successfully recalled negative pictures in the posterior cingulate cortex and medial prefrontal cortex. These findings indicate that neural activation in cortical midline regions is a better predictor of long-term symptomatic outcome than is memory sensitivity for negative material.
View details for DOI 10.1097/WNR.0000000000000095
View details for Web of Science ID 000332601600009
- Understanding Familial Risk for Depression: A 25-Year Perspective PERSPECTIVES ON PSYCHOLOGICAL SCIENCE 2014; 9 (1): 94-108
Understanding Familial Risk for Depression: A 25-Year Perspective.
Perspectives on psychological science
2014; 9 (1): 94-108
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.
View details for DOI 10.1177/1745691613513469
View details for PubMedID 26173248
Structural abnormality of the corticospinal tract in major depressive disorder.
Biology of mood & anxiety disorders
2014; 4: 8-?
Scientists are beginning to document abnormalities in white matter connectivity in major depressive disorder (MDD). Recent developments in diffusion-weighted image analyses, including tractography clustering methods, may yield improved characterization of these white matter abnormalities in MDD. In this study, we acquired diffusion-weighted imaging data from MDD participants and matched healthy controls. We analyzed these data using two tractography clustering methods: automated fiber quantification (AFQ) and the maximum density path (MDP) procedure. We used AFQ to compare fractional anisotropy (FA; an index of water diffusion) in these two groups across major white matter tracts. Subsequently, we used the MDP procedure to compare FA differences in fiber paths related to the abnormalities in major fiber tracts that were identified using AFQ.FA was higher in the bilateral corticospinal tracts (CSTs) in MDD (p's < 0.002). Secondary analyses using the MDP procedure detected primarily increases in FA in the CST-related fiber paths of the bilateral posterior limbs of the internal capsule, right superior corona radiata, and the left external capsule.This is the first study to implicate the CST and several related fiber pathways in MDD. These findings suggest important new hypotheses regarding the role of CST abnormalities in MDD, including in relation to explicating CST-related abnormalities to depressive symptoms and RDoC domains and constructs.
View details for DOI 10.1186/2045-5380-4-8
View details for PubMedID 25295159
The Neural Basis of Difficulties Disengaging From Negative Irrelevant Material in Major Depression
2013; 24 (3): 334-344
Recurrent uncontrollable negative thoughts are a hallmark of depressive episodes. Deficits in cognitive control have been proposed to underlie this debilitating aspect of depression. Here, we used functional neuroimaging during an emotional working memory (WM) task to elucidate the neural correlates of these difficulties in cognitive control. In a WM manipulation involving depressed participants, the dorsal anterior cingulate and parietal and bilateral insular cortices were activated significantly more when negative words were removed from WM than when they were maintained in WM; in contrast, nondepressed participants exhibited stronger neural activations in these regions for positive than for negative material. These findings implicate anomalous activation of components of the task-positive network, known to be modulated by cognitive effort, in depression-associated difficulties in expelling negative material from WM. Future studies should examine the association between these aberrations and the maintenance of depressive symptoms.
View details for DOI 10.1177/0956797612457380
View details for Web of Science ID 000316640900014
Neurobiological markers of familial risk for depression.
Current topics in behavioral neurosciences
2013; 14: 181-206
Major depression is associated with a wide range of neurobiological disturbances, including anomalies in the structure and function of cortical and subcortical gray matter and dysregulation of the HPA axis. In this chapter, we review research demonstrating that many of these abnormalities are also present in never-depressed offspring of adults with recurrent depression and discuss how such findings might reflect dysfunctional neuroregulatory systems that precede the onset of this disorder. We also briefly discuss candidate genes and environmental factors that have been posited to be directly involved in the transmission of neural and HPA-axis abnormalities from depressed parents to their offspring, and we review how, by obtaining a better understanding of the neurobiological markers of depression risk, we can facilitate the development of targeted strategies for the prevention and treatment of major depression.
View details for DOI 10.1007/7854_2012_213
View details for PubMedID 22573472
ADHD comorbidity can matter when assessing cortical thickness abnormalities in patients with bipolar disorder
2012; 14 (8): 843-855
Attention-deficit hyperactivity disorder (ADHD) is prevalent in patients with bipolar disorder (BP), but very few studies consider this when interpreting magnetic resonance imaging findings. No studies, to our knowledge, have screened for or controlled for the presence of ADHD when examining cortical thickness in patients with BP. We used a 2 × 2 design to evaluate the joint effects of BP and ADHD on cortical thickness and uncover the importance of ADHD comorbidity in BP subjects.The study included 85 subjects: 31 healthy controls, 17 BP-only, 19 ADHD-only, and 18 BP/ADHD. All patients with BP were subtype I, euthymic, and not taking lithium. Groups did not differ significantly in age or gender distribution. We used cortical thickness measuring tools combined with cortical pattern matching methods to align sulcal/gyral anatomy across participants. Significance maps were used to check for both main effects of BP and ADHD and their interaction. Post-hoc comparisons assessed how the effects of BP on cortical thickness varied as a function of the presence or absence of ADHD.Interactions of BP and ADHD diagnoses were found in the left subgenual cingulate and right orbitofrontal cortex, demonstrating that the effect of BP on cortical thickness depends on ADHD status.Some brain abnormalities attributed to BP may result from the presence of ADHD. Diagnostic interactions were found in regions previously implicated in the pathophysiology of BP, making it vital to control for an ADHD comorbid diagnosis when attempting to isolate neural or genetic abnormalities specific to BP.
View details for DOI 10.1111/bdi.12024
View details for Web of Science ID 000311403600006
View details for PubMedID 23167934
Deficits in inferior frontal cortex activation in euthymic bipolar disorder patients during a response inhibition task
2012; 14 (4): 442-450
The inferior frontal cortical-striatal network plays an integral role in response inhibition in normal populations. While inferior frontal cortex (IFC) impairment has been reported in mania, this study explored whether this dysfunction persists in euthymia.Functional magnetic resonance imaging (fMRI) activation was evaluated in 32 euthymic patients with bipolar I disorder and 30 healthy subjects while performing the Go/NoGo response inhibition task. Behavioral data were collected to evaluate accuracy and response time. Within-group and between-group comparisons of activation were conducted using whole-brain analyses to probe significant group differences in neural function.Both groups activated bilateral IFC. However, between-group comparisons showed a significantly reduced activation in this brain region in euthymic patients with bipolar disorder compared to healthy subjects. Other frontal and basal ganglia regions involved in response inhibition were additionally significantly reduced in bipolar disorder patients, in both the medicated and the unmedicated subgroups. No areas of greater activation were observed in bipolar disorder patients versus healthy subjects.Bipolar disorder patients, even during euthymia, have a persistent reduction in activation of brain regions involved in response inhibition, suggesting that reduced activation in the orbitofrontal cortex and striatum is not solely related to the state of mania. These findings may represent underlying trait abnormalities in bipolar disorder.
View details for DOI 10.1111/j.1399-5618.2012.01020.x
View details for Web of Science ID 000304441200008
View details for PubMedID 22631623
Anterior cingulate activation relates to local cortical thickness
2012; 23 (7): 420-424
Few studies have examined the relationship between local anatomic thickness of the cortex and the activation signals arising from it. Using structural and functional MRI, we examined whether a relationship exists between cortical thickness and brain activation. Twenty-eight participants were asked to perform the Go/NoGo response inhibition task known to activate the anterior cingulate and the prefrontal cortex. Structural data of the same regions were simultaneously collected. We hypothesized that cortical thickness in these brain regions would positively correlate with brain activation. Data from the structural MRI were aligned with those of functional MRI activation. There was a positive linear correlation between cortical thickness and activation during response inhibition in the right anterior cingulate cortex (Brodmann's Area 24). No significant thickness-activation correlations were found in the prefrontal cortex. Correlations between cortical thickness and activation may occur only in certain brain regions.
View details for DOI 10.1097/WNR.0b013e3283525a95
View details for Web of Science ID 000302948500003
View details for PubMedID 22440976
Cognitive and neural aspects of information processing in major depressive disorder: an integrative perspective.
Frontiers in psychology
2012; 3: 489-?
Researchers using experimental paradigms to examine cognitive processes have demonstrated that Major Depressive Disorder (MDD) is associated not with a general deficit in cognitive functioning, but instead with more specific anomalies in the processing of negatively valenced material. Indeed, cognitive theories of depression posit that negative biases in the processing of information play a critical role in influencing the onset, maintenance, and recurrence of depressive episodes. In this paper we review findings from behavioral studies documenting that MDD is associated with specific difficulties in attentional disengagement from negatively valenced material, with tendencies to interpret information in a negative manner, with deficits in cognitive control in the processing of negative material, and with enhanced memory for negative material. To gain a better understanding of the neurobiological basis of these abnormalities, we also examine findings from functional neuroimaging studies of depression and show that dysfunction in neural systems that subserve emotion processing, inhibition, and attention may underlie and contribute to the deficits in cognition that have been documented in depressed individuals. Finally, we briefly review evidence from studies of children who are at high familial risk for depression that indicates that abnormalities in cognition and neural function are observable before the onset of MDD and, consequently, may represent a risk factor for the development of this disorder. By integrating research from cognitive and neural investigations of depression, we can gain a more comprehensive understanding not only of how cognitive and biological factors interact to affect the onset, maintenance, and course of MDD, but also of how such research can aid in the development of targeted strategies for the prevention and treatment of this debilitating disorder.
View details for DOI 10.3389/fpsyg.2012.00489
View details for PubMedID 23162521
- Cognitive and neural aspects of information processing in major depressive disorder: an integrative perspective FRONTIERS IN PSYCHOLOGY 2012; 3