ELUCIDATING BRAIN CONNECTIVITY NETWORKS IN MAJOR DEPRESSIVE DISORDER USING CLASSIFICATION-BASED SCORING.

Graph theory is increasingly used in the field of neuroscience to understand the large-scale network structure of the human brain. There is also considerable interest in applying machine learning techniques in clinical settings, for example, to make diagnoses or predict treatment outcomes. Here we used support-vector machines (SVMs), in conjunction with whole-brain tractography, to identify graph metrics that best differentiate individuals with Major Depressive Disorder (MDD) from nondepressed controls.

The impact of depression on Veterans with PTSD and traumatic brain injury: a diffusion tensor imaging study.

A significant proportion of military personnel deployed in support of Operation Enduring Freedom and Operation Iraqi Freedom were exposed to war-zone events associated with traumatic brain injury (TBI), depression (DEP) and posttraumatic stress disorder (PTSD). The co-occurrence of TBI, PTSD and DEP in returning Veterans has recently increased research and clinical interest. This study tested the hypothesis that white matter abnormalities are further impacted by depression.

CHARACTERIZING WHITE MATTER CONNECTIVITY IN MAJOR DEPRESSIVE DISORDER: AUTOMATED FIBER QUANTIFICATION AND MAXIMUM DENSITY PATHS.

Diffusion-weighted imaging allows for assessment of white matter structure, which can be used to assess aberrations associated with disease. Several new methods permit the automated assessment of important white matter characteristics. In the current study we used Automated Fiber Quantification (AFQ) to assess differences between depressed and nondepressed individuals in 18 major white matter tracts.

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.

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.

Structural abnormality of the corticospinal tract in major depressive disorder.

Background: 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.

Telomere length and cortisol reactivity in children of depressed mothers.

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.

The neuroscience of depression: implications for assessment and intervention.

Major Depressive Disorder (MDD) is among the most prevalent of all psychiatric disorders and is the single most burdensome disease worldwide. In attempting to understand the profound deficits that characterize MDD across multiple domains of functioning, researchers have identified aberrations in brain structure and function in individuals diagnosed with this disorder. In this review we synthesize recent data from human neuroimaging studies in presenting an integrated neural network framework for understanding the impairments experienced by individuals with MDD.

Increased coupling of intrinsic networks in remitted depressed youth predicts rumination and cognitive control.

Objective: Functional connectivity MRI (fcMRI) studies of individuals currently diagnosed with major depressive disorder (MDD) document hyperconnectivities within the default mode network (DMN) and between the DMN and salience networks (SN) with regions of the cognitive control network (CCN). Studies of individuals in the remitted state are needed to address whether effects derive from trait, and not state or chronic burden features of MDD.

Method: fcMRI data from two 3.

Reward processing in healthy offspring of parents with bipolar disorder.

Importance: Bipolar disorder (BD) is highly familial and characterized by deficits in reward processing. It is not known, however, whether these deficits precede illness onset or are a consequence of the disorder.

Objective: To determine whether anomalous neural processing of reward characterizes children at familial risk for BD in the absence of a personal history of a psychopathologic disorder.

Distinctive and common neural underpinnings of major depression, social anxiety, and their comorbidity.

Assessing neural commonalities and differences among depression, anxiety and their comorbidity is critical in developing a more integrative clinical neuroscience and in evaluating currently debated categorical vs dimensional approaches to psychiatric classification. Therefore, in this study, we sought to identify patterns of anomalous neural responding to criticism and praise that are specific to and common among major depressive disorder (MDD), social anxiety disorder (SAD) and comorbid MDD-SAD. Adult females who met formal diagnostic criteria for MDD, SAD or MDD-SAD and psychiatrically healthy participants underwent functional magnetic resonance imaging as they listened to statements directing praise or criticism at them or at another person.

Early signs of anomalous neural functional connectivity in healthy offspring of parents with bipolar disorder.

Objectives: Bipolar disorder (BD) has been associated with dysfunctional brain connectivity and with family chaos. It is not known whether aberrant connectivity occurs before illness onset, representing vulnerability for developing BD amidst family chaos. We used resting-state functional magnetic resonance imaging (fMRI) to examine neural network dysfunction in healthy offspring living with parents with BD and healthy comparison youth.

Children at risk for depression: memory biases, self-schemas, and genotypic variation.

Background: Daughters of depressed mothers are at increased risk for developing a depressive disorder. We know relatively little, however, about the specific factors that contribute to this elevated risk. The present study investigated the effects of familial risk for depression and the 5-HTTLPR and COMT Val158Met polymorphisms, which have been associated with risk for depression, on biases in endorsement of and memory for positive and negative adjectives.

Melancholia in later life: late and early onset differences in presentation, course, and dementia risk.

Objectives: Depression is a risk factor for cognitive decline and dementia. This risk may vary with age of onset and depression subtype. Late onset depression (LOD, 60 years and older) is associated with more cognitive decline, whereas early onset depression (EOD, before 60 years) is associated with more residual depressive symptoms.

The role of the medial frontal cortex in the maintenance of emotional states.

Evidence is accruing that people can maintain their emotional states, but how they do it and which brain regions are responsible still remains unclear. We examined whether people maintain emotional states 'actively', with explicit elaboration of the emotion, or 'passively', without elaboration. Twenty-four participants completed an emotion maintenance task in which they either maintained the emotional intensity from the first picture of a pair to compare to that of the second picture ('maintain' condition), or only rated their emotional response to the second picture ('non-maintain' condition).

Increased insula coactivation with salience networks in insomnia.

Insomnia is among the most prevalent and costly of all sleep-related disorders. To characterize the neural mechanisms underlying subjective dysfunction in insomnia, we examined brain activity in 17 female insomniacs and 17 female healthy controls using simultaneous functional magnetic resonance imaging (fMRI) and electroencephalography (EEG) while they were resting and while they were trying to fall asleep. In examining the dynamic regional activity within intrinsic brain networks, we found that, compared with controls, insomniacs had greater involvement of the anterior insula with salience networks, as well as insula BOLD correlation with EEG gamma frequency power during rest in insomniacs.

Memory for novel positive information in major depressive disorder.

Major depressive disorder (MDD) is associated with biases in memory, including poor memory for positive stimuli. It is unclear, however, if this impaired memory for positive stimuli in MDD is related to difficulties in the initial processing of stimuli, or alternatively, reflects a decreased ability to draw on memories of positive stimuli after they have been formed. Using two versions of a word-matching task that featured a mixture of novel and practiced emotionally valenced words, we found that depressed individuals experienced greater difficulty learning positively valenced information than did their nondepressed peers.

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.

Activation of the medial prefrontal and posterior cingulate cortex during encoding of negative material predicts symptom worsening in major depression.

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.

DeCon: a tool to detect emotional concordance in multivariate time series data of emotional responding.

The occurrence of concordance among different response components during an emotional episode is a key feature of several contemporary accounts and definitions of emotion. Yet, capturing such response concordance in empirical data has proven to be elusive, in large part because of a lack of appropriate statistical tools that are tailored to measure the intricacies of response concordance in the context of data on emotional responding. In this article, we present a tool we developed to detect two different forms of response concordance-response patterning and synchronization-in multivariate time series data of emotional responding, and apply this tool to data concerning physiological responding to emotional stimuli.

Recalling happy memories in remitted depression: a neuroimaging investigation of the repair of sad mood.

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.

Interoceptive awareness, positive affect, and decision making in major depressive disorder.

Background: Little work has examined the relation between interoceptive awareness and symptoms of Major Depressive Disorder (MDD). Existing research suggests that depressed individuals exhibit impaired heartbeat perception, though the results of this research have been equivocal. Importantly, depressed participants in these studies have had comorbid anxiety disorders, making it difficult to draw inferences about interoceptive awareness in MDD.

The role of attention to emotion in recovery from major depressive disorder.

Major Depressive Disorder (MDD) is characterized by several emotional disturbances. One possible but not well-examined disturbance is in attention to emotion, an important facet of emotional awareness. We examined whether attention to emotion predicted recovery from MDD.

Using multiple methods to characterize the phenotype of individuals with a family history of major depressive disorder.

Background: Unaffected relatives (URs) of individuals with major depressive disorder (MDD) are biologically more vulnerable to depression. We compare healthy URs and controls at the level of phenotype (symptoms and functioning) and endophenotype (negative emotion bias), and further investigate the interrelation between these and the contribution of environmental early life stress.

Methods: URs (n=101), identified using Family History Screen interview methods and matched controls completed written and interview questions assessing symptoms of depression and anxiety, negative cognitive style, life functioning and early life stress.