Sensation Seeking in Children and Adults with Pediatric-Onset Bipolar Disorder.

Bipolar disorder (BD) is one of the most impairing psychiatric illnesses. Those with pediatric-onset BD tend to have worse outcomes; therefore, accurate conceptualization is important for aspects of care, such as tailored treatment interventions. Sensation seeking behaviors may be a window into the psychopathology of pediatric-onset BD. Participants with BD and healthy controls (HC) ages 7-27 completed self-report assessments, including the Sensation Seeking Scale- V (SSS-V). Among the BD group, there was a significant positive correlation between the Disinhibition subscale and age. Analyses indicated that the BD group scored lower on the Thrill and Adventure Seeking subscale but higher on the Disinhibition scale when compared to the HC group. We found that individuals with pediatric-onset BD are more likely to engage in socially risky behaviors. These results are an important step in understanding sensation seeking characteristics in BD youth and improving treatment, ultimately helping individuals live a more stable life.

Relationship between cognitive flexibility and subsequent course of mood symptoms and suicidal ideation in young adults with childhood-onset bipolar disorder.

Neurocognitive deficits, such as cognitive flexibility impairments, are common in bipolar disorder (BD) and predict poor academic, occupational, and functional outcomes. However, the association between neurocognition and illness trajectory is not well understood, especially across developmental transitions. This study examined cognitive flexibility and subsequent mood symptom and suicidal ideation (SI) course in young adults with childhood-onset BD-I (with distinct mood episodes) vs. BD-not otherwise specified (BD-NOS) vs. typically-developing controls (TDCs). Sample included 93 young adults (ages 18-30) with prospectively verified childhood-onset DSM-IV BD-I (n = 34) or BD-NOS (n = 15) and TDCs (n = 44). Participants completed cross-sectional neuropsychological tasks and clinical measures. Then participants with BD completed longitudinal assessments of mood symptoms and SI at 6-month intervals (M = 39.18 ± 16.57 months of follow-up data). Analyses included ANOVAs, independent-samples t tests, chi-square analyses, and multiple linear regressions. Participants with BD-I had significant deficits in cognitive flexibility and executive functioning vs. BD-NOS and TDCs, and impaired spatial working memory vs. TDCs only. Two significant BD subtype-by-cognitive flexibility interactions revealed that cognitive flexibility deficits were associated with subsequent percentage of time depressed and with SI in BD-I but not BD-NOS, regardless of other neurocognitive factors (full-scale IQ, executive functioning, spatial working memory) and clinical factors (current and prior mood and SI symptoms, age of BD onset, global functioning, psychiatric medications, comorbidity). Thus, cognitive flexibility may be an important etiological brain/behavior mechanism, prognostic indicator, and intervention target for childhood-onset BD-I, as this deficit appears to endure into young adulthood and is associated with worse prognosis for subsequent depression and SI.

Facial emotion recognition and mood symptom course in young adults with childhood-onset bipolar disorder.

Facial emotion recognition deficits are common in bipolar disorder (BD) and associated with impairment. However, the relationship between facial emotion recognition and mood course is not well understood. This study examined facial emotion recognition and subsequent mood symptoms in young adults with childhood-onset BD versus typically developing controls (TDCs). The sample included 116 young adults (ages 18-30, 58% male, 78% White) with prospectively verified childhood-onset BD (n = 52) and TDCs (n = 64). At baseline, participants completed a facial emotion recognition task (Diagnostic Analysis of Non-Verbal Accuracy-2) and clinical measures. Then, participants with BD completed mood symptom assessments every 6 months (M = 8.7 ± 5.2 months) over two years. Analyses included independent-samples t tests and mixed-effects regression models. Participants with BD made significantly more recognition errors for child expressions than TDCs. There were no significant between-group differences for recognition errors for adult expressions, or errors for specific child or adult emotional expressions. Participants had moderate baseline mood symptoms. Significant time-by-facial emotion recognition interactions revealed more recognition errors for child emotional expressions predicted lower baseline mania and stable/consistent trajectory; fewer recognition errors for child expressions predicted higher baseline mania and decreasing trajectory. In addition, more recognition errors for adult sad expressions predicted stable/consistent depression trajectory and decreasing mania; fewer recognition errors for adult sad expressions predicted decreasing depression trajectory and stable/consistent mania. Effects remained when controlling for baseline demographics and clinical variables. Facial emotion recognition may be an important brain/behavior mechanism, prognostic indicator, and intervention target for childhood-onset BD, which endures into young adulthood and is associated with mood trajectory.

Family-focused cognitive behavioral treatment for depressed adolescents in suicidal crisis with co-occurring risk factors: a randomized trial.

BACKGROUND: Suicide is the second leading cause of death among adolescents. The purpose of this study was to test a family-focused outpatient cognitive behavioral treatment (F-CBT) protocol for depressed adolescents following psychiatric hospitalization for a suicide attempt or suicidal ideation, and who had a co-occurring risk factor (suicidal behavior prior to the index admission, nonsuicidal self-injury, and/or a substance use disorder), in a randomized Phase 2 efficacy trial. METHOD: One hundred forty-seven adolescents (mean age = 14.91 years; 76.2% female, 85.5% White) and their families, recruited primarily from an inpatient psychiatric hospitalization program, were randomly assigned to F-CBT or enhanced treatment-as-usual (E-TAU). A suicide attempt was the primary outcome variable. Depression, suicidal ideation, and nonsuicidal self-injury are also reported here. Assessments were completed at pretreatment as well as 6, 12, and 18-months postrandomization (Trial Registration ClinicalTrials.gov Identifier: NCT01732601). RESULTS: In the sample as a whole, rates of attempts decreased from 20% at 6 months to 9% at 12 months to 7% at 18 months. There was no evidence of a significant difference between treatment arms in rates of suicide attempts, major depressive disorder, suicidal ideation, or nonsuicidal self-injury at any of the postrandomization assessment points. CONCLUSIONS: Though F-CBT was associated with reductions in suicidality, depression, and nonsuicidal self-injury, E-TAU showed an equally strong effect. Greater frequency of F-CBT treatment sessions, particularly at the start of care, and alternative approaches to transitioning to care at 12 months, may be necessary when using F-CBT with this population.

Cognitive performance of youth with primary generalized anxiety disorder versus primary obsessive-compulsive disorder.

BACKGROUND: Despite gains made in the study of childhood anxiety, differential diagnosis remains challenging because of indistinct boundaries between disorders and high comorbidity. This is certainly true for generalized anxiety disorder (GAD) and obsessive-compulsive disorder (OCD) as they share multiple cognitive processes (e.g., rumination, intolerance of uncertainty, and increased attention to threat). Disentangling such cognitive characteristics and, subsequently, underlying mechanisms could serve to inform assessment and treatment practices, and improve prognoses. METHODS: The current study sought to compare the cognitive performance (working memory, visuospatial memory, planning ability/efficiency, and cognitive flexibility), indexed by the Cambridge Neuropsychological Automated Battery (CANTAB) among three nonoverlapping groups of youth: (1) those diagnosed with OCD (n = 28), (2) those diagnosed with GAD, not OCD (n = 34), and (3) typically-developing controls (TDC) (n = 65). RESULTS: Results showed that OCD and GAD youth demonstrated neurocognitive deficits in planning ability/efficiency, cognitive flexibility, and visual processing when compared to TDC, with potential diagnostic specificity such that youth with GAD or OCD had unique deficits compared to TDC and to one another. Specifically, youth with OCD demonstrated significantly impaired planning ability compared to youth in the GAD and TDS groups, whereas youth with GAD demonstrated greater cognitive inflexibility and delayed visual processing compared to youth in the OCD and TDC groups. CONCLUSIONS: Future studies should expand upon these findings with more comprehensive assessment of cognitive functioning by including self- and parent-report forms, and neuroimaging to link behavioral findings with subjective ratings and neurocircuitry. Altogether, data can then inform future assessment and treatment targets.

A Pilot Study of Neural Correlates of Loss of Control Eating in Children With Overweight/Obesity: Probing Intermittent Access to Food as a Means of Eliciting Disinhibited Eating.

Objective: Neural substrates of loss of control (LOC) eating are undercharacterized. We aimed to model intermittent access to food to elicit disinhibited eating in youth undergoing neuroimaging, given evidence that restricted food access may increase subsequent food intake via enhancing reward value of food and diminishing eating-related self-control. Methods: Participants were 18 preadolescents (aged 9-12 years) who were overweight/obese with recent LOC eating (OW-LOC; n = 6); overweight/obese with no history of LOC eating (OW-CON; n = 5); or non-overweight with no history of LOC eating (NW-CON; n = 7). Participants underwent functional magnetic resonance imaging during a simulated food restriction paradigm in which they were alternately given restricted or unrestricted access to milkshake solutions. Results: There were no significant main effects of restricted versus unrestricted access to milkshake flavors. Group main effects revealed increased activation for OW-LOC relative to OW-CON in areas related to attentional processes (right middle frontal gyrus), inhibitory control/attentional shifts (right and left cuneus), and emotion regulation (left cingulate gyrus); and for OW-LOC relative to NW-CON in areas related to response inhibition (right inferior frontal gyrus). Significant block type × group interaction effects were found for the right middle frontal gyrus, left cingulate gyrus, and left cuneus, but these appeared to be accounted for primarily by group. Discussion: There were clear group differences in neural activity in brain regions related to self-regulation during a food restriction paradigm. Elevations in these regions among OW-LOC relative to OW-CON and NW-CON, respectively, may suggest that youth with LOC eating expended more cognitive effort to regulate ingestive behavior.

Longitudinal cognitive trajectories and associated clinical variables in youth with bipolar disorder.

OBJECTIVE: There is substantial interest in delineating the course of cognitive functioning in bipolar (BP) youth. However, there are no longitudinal studies aimed at defining subgroups of BP youth based on their distinctive cognitive trajectories and their associated clinical variables. METHOD: Cognitive functioning was measured in 135 participants from the Course and Outcome of BP Youth (COBY) study using several subtests of the Cambridge Neuropsychological Test Automated Battery (CANTAB). Youth were prospectively evaluated three times on average every 13.75 months over 2.5 years. Clinical and functional outcomes were assessed using the Longitudinal Interval Follow-Up Evaluation (LIFE). RESULTS: Latent class growth analysis identified three longitudinal patterns of cognitive functioning based on a general cognitive index: class 1, "persistently high" (N=21; 15.6%); class 2, "persistently moderate" (N=82; 60.74%); and class 3, "persistently low" (N=32; 23.7%). All classes showed normal cognitive functioning when compared with the CANTAB normative data. After adjustment for confounders, youth from class 3 had a significantly greater percentage of time with overall, manic, and depressive syndromal symptoms than youth in the other two classes. Also, after adjustment for confounders, youth from class 3 had significantly poorer global, academic, and social functioning than youth from class 1. CONCLUSIONS: BP youth showed normal overall cognitive functioning that remained stable during the follow-up within each class. However, 24% of BP youth showed poorer cognitive functioning than the other BP youth. This subgroup had poorer mood course and functioning, and may benefit from cognitive remediation and early management with evidence-based pharmacological treatments.

Depression with Mixed Features in Adolescent Psychiatric Patients.

Depression with mixed features is poorly understood, especially in pediatric samples. This study compares symptoms and correlates of depressed adolescent inpatients with mixed features to inpatients with bipolar disorder and major depression. 407 adolescents were administered diagnostic interviews and self-reports, and 262 were categorized as Depression with Mixed Features (MXD; n = 38), Consensus Bipolar (CB; n = 79), or Depression Only (DO; n = 145). Demographic and morbidity information were collected via chart reviews. MXD adolescents evidenced elevated mania-related symptoms compared to DO adolescents. MXD adolescents had elevated Unusually Energetic symptoms and increases for six additional category B mania-related symptoms compared to CB adolescents. MXD adolescents met criteria for more comorbid disorders and reported elevated suicidality, anger, and trauma symptoms compared to CB and DO adolescents. Overall, MXD adolescents evidenced elevated symptomatology compared to other groups, suggesting mixed depression may represent a unique constellation of symptoms meriting further investigation.

Emotional face recognition in adolescent suicide attempters and adolescents engaging in non-suicidal self-injury.

Little is known about the bio-behavioral mechanisms underlying and differentiating suicide attempts from non-suicidal self-injury (NSSI) in adolescents. Adolescents who attempt suicide or engage in NSSI often report significant interpersonal and social difficulties. Emotional face recognition ability is a fundamental skill required for successful social interactions, and deficits in this ability may provide insight into the unique brain-behavior interactions underlying suicide attempts versus NSSI in adolescents. Therefore, we examined emotional face recognition ability among three mutually exclusive groups: (1) inpatient adolescents who attempted suicide (SA, n = 30); (2) inpatient adolescents engaged in NSSI (NSSI, n = 30); and (3) typically developing controls (TDC, n = 30) without psychiatric illness. Participants included adolescents aged 13-17 years, matched on age, gender and full-scale IQ. Emotional face recognition was evaluated using the diagnostic assessment of nonverbal accuracy (DANVA-2). Compared to TDC youth, adolescents with NSSI made more errors on child fearful and adult sad face recognition while controlling for psychopathology and medication status (ps < 0.05). No differences were found on emotional face recognition between NSSI and SA groups. Secondary analyses showed that compared to inpatients without major depression, those with major depression made fewer errors on adult sad face recognition even when controlling for group status (p < 0.05). Further, compared to inpatients without generalized anxiety, those with generalized anxiety made fewer recognition errors on adult happy faces even when controlling for group status (p < 0.05). Adolescent inpatients engaged in NSSI showed greater deficits in emotional face recognition than TDC, but not inpatient adolescents who attempted suicide. Further results suggest the importance of psychopathology in emotional face recognition. Replication of these preliminary results and examination of the role of context-dependent emotional processing are needed moving forward.

Cognitive flexibility and performance in children and adolescents with threshold and sub-threshold bipolar disorder.

Greater understanding of cognitive function in children and adolescents with bipolar disorder (BD) is of critical importance to improve our ability to design targeted treatments to help with real-world impairment, including academic performance. We sought to evaluate cognitive performance among children with either BD type I, II, or "not otherwise specified" (NOS) participating in multi-site Course and Outcome of Bipolar Youth study compared to typically developing controls (TDC) without psychopathology. In particular, we sought to test the hypothesis that BD-I and BD-II youths with full threshold episodes of mania or hypomania would have cognitive deficits, including in reversal learning, vs. those BD-NOS participants with sub-threshold episodes and TDCs. N = 175 participants (BD-I = 81, BD-II = 11, BD-NOS = 28, TDC = 55) completed Cambridge Neuropsychological Automated Testing Battery (CANTAB) tasks. A priori analyses of the simple reversal stage of the CANTAB intra-/extra-dimensional shift task showed that aggregated BD-I/II participants required significantly more trials to complete the task than either BD-NOS participants with sub-syndromal manic/hypomanic symptoms or than TDCs. BD participants across sub-types had impairments in sustained attention and information processing for emotionally valenced words. Our results align with prior findings showing that BD-I/II youths with distinct episodes have specific alterations in reversal learning. More broadly, our study suggests that further work is necessary to see the interaction between neurocognitive performance and longitudinal illness course. Additional work is required to identify the neural underpinnings of these differences as targets for potential novel treatments, such as cognitive remediation.

Facial emotion recognition in childhood-onset bipolar I disorder: an evaluation of developmental differences between youths and adults.

OBJECTIVES: Bipolar disorder (BD) is a severe mental illness with high healthcare costs and poor outcomes. Increasing numbers of youths are diagnosed with BD, and many adults with BD report that their symptoms started in childhood, suggesting that BD can be a developmental disorder. Studies advancing our understanding of BD have shown alterations in facial emotion recognition both in children and adults with BD compared to healthy comparison (HC) participants, but none have evaluated the development of these deficits. To address this, we examined the effect of age on facial emotion recognition in a sample that included children and adults with confirmed childhood-onset type-I BD, with the adults having been diagnosed and followed since childhood by the Course and Outcome in Bipolar Youth study. METHODS: Using the Diagnostic Analysis of Non-Verbal Accuracy, we compared facial emotion recognition errors among participants with BD (n = 66; ages 7-26 years) and HC participants (n = 87; ages 7-25 years). Complementary analyses investigated errors for child and adult faces. RESULTS: A significant diagnosis-by-age interaction indicated that younger BD participants performed worse than expected relative to HC participants their own age. The deficits occurred both for child and adult faces and were particularly strong for angry child faces, which were most often mistaken as sad. Our results were not influenced by medications, comorbidities/substance use, or mood state/global functioning. CONCLUSIONS: Younger individuals with BD are worse than their peers at this important social skill. This deficit may be an important developmentally salient treatment target - that is, for cognitive remediation to improve BD youths' emotion recognition abilities.

Self-injurious implicit attitudes among adolescent suicide attempters versus those engaged in nonsuicidal self-injury.

BACKGROUND: Suicide is among the most important mental health issues affecting adolescents today despite much research on its detection and prevention. Beyond suicide attempts (SAs), clinicians are increasingly confronted with another, potentially related problem: non-suicidal self-injury (NSSI)-defined as the deliberate destruction of body tissue without intent to die. NSSI may increase risk for making an SA by sevenfold, but many studies examining this link have involved youths engaging in both NSSI and SAs. Thus, there is a need to compare homogeneous groups of adolescents engaged in NSSI-only or SA-only, but not both, to advance what is known about each form of self-harm. The self-injurious implicit association task (SI-IAT) is a particularly important computerized behavioral task to study such adolescents because the SI-IAT provides objective behavioral data about problems for which people may lack insight or be motivated to conceal, such as SAs and NSSI. METHODS: We evaluated implicit associations with cutting and death/suicide using the computerized SI-IAT in three mutually exclusive groups: (1) adolescents who made an SA but had never engaged in NSSI (n = 47); (2) adolescents who engaged in NSSI but had never made an SA (n = 46); and (3) typically developing control (TDC) adolescents without history of psychiatric problems (n = 43). RESULTS: Nonsuicidal self-injury participants had stronger identification with cutting versus no cutting than either SA or TDC participants. Contrary to our hypothesis, NSSI participants had stronger identification with suicide/death versus life than either SA or TDC participants. CONCLUSIONS: Strong implicit attitudes towards suicide/death among adolescents with NSSI without a prior SA suggest that clinicians should not dismiss NSSI as not serious. Further work is required to elucidate the mechanism by which youths engaged in NSSI acquire these stronger identifications and make a first-time SA to develop novel treatment and prevention strategies blocking this transformation, ultimately reducing youth suicide.

Cognitive remediation: potential novel brain-based treatment for bipolar disorder in children and adolescents.

Bipolar disorder (BD) is among the most impairing psychiatric disorders affecting children and adolescents, despite our best psychopharmacological and psychotherapeutic treatments. Cognitive remediation, defined as a behavioral intervention designed to improve cognitive functions so as to reduce psychiatric illness, is an emerging brain-based treatment approach that has thus far not been studied in pediatric BD. The present article reviews the basic principles of cognitive remediation, describes what is known about cognitive remediation in psychiatric disorders, and delineates potential brain/behavior alterations implicated in pediatric BD that might be targets for cognitive remediation. Emerging data show that cognitive remediation may be useful in children and adults with schizophrenia, ADHD, and anxiety disorders, and in adults with BD. Potential targets for cognitive remediation in pediatric BD include face processing, response inhibition, frustration, and cognitive flexibility. Further study is warranted to determine if cognitive remediation for these targets, or others, may serve as a novel, brain-based treatment for pediatric BD.

Affective processing bias in youth with primary bipolar disorder or primary attention-deficit/hyperactivity disorder.

High rates of comorbidity and overlapping diagnostic criteria between pediatric bipolar disorder (BD) and attention-deficit/hyperactivity disorder (ADHD) contribute to diagnostic and treatment confusion. To advance what is known about both disorders, we compared effect of emotional stimuli on response control in children with primary BD, primary ADHD and typically developing controls (TDC). Participants included 7-17 year olds with either "narrow-phenotype" pediatric BD (n = 25), ADHD (n = 25) or TDC (n = 25). Groups were matched on participant age and FSIQ. The effect of emotional stimuli on response control was assessed using the Cambridge Neuropsychological Test Automated Battery Affective Go/No-Go task (CANTAB AGN). We found a group by target valence interaction on commission errors [F(2,71) = 5.34, p < 0.01, ƞ p (2) = 0.13] whereby ADHD, but not TDC participants, made more errors on negative than positive words [t(24) = -2.58, p < 0.05, r = 0.47]. In contrast, there was a nonsignificant trend for BD participants to make fewer errors on negative versus positive words compared to ADHD and TDC participants. Between-subjects effects showed that ADHD participants made more errors than TDC, but not BD participants. Our main finding advances what is known about the effect of emotional stimuli on response control in children with ADHD. Our results suggesting a positive affective processing bias in children with ADHD compliment emerging literature show that difficulties with emotional processing and regulation may be core features of ADHD. Further, given the observed pattern of results in children with ADHD compared to BD children, our behavioral results suggest the importance of examining differences in the brain-behavior mechanisms involved in affective processing in children with ADHD compared to BD children.

Irritability in Youths: A Critical Integrative Review.

Irritability, defined as proneness to anger that may impair an individual's functioning, is common in youths. There has been a recent upsurge in relevant research. The authors combine systematic and narrative review approaches to integrate the latest clinical and translational findings and provide suggestions for addressing research gaps. Clinicians and researchers should assess irritability routinely, and specific assessment tools are now available. Informant effects are prominent, are stable, and vary by age and gender. The prevalence of irritability is particularly high among individuals with attention deficit hyperactivity disorder, autism spectrum disorder, and mood and anxiety disorders. Irritability is associated with impairment and suicidality risk independent of co-occurring diagnoses. Developmental trajectories of irritability (which may begin early in life) have been identified and are differentially associated with clinical outcomes. Youth irritability is associated with increased risk of anxiety, depression, behavioral problems, and suicidality later in life. Irritability is moderately heritable, and genetic associations differ based on age and comorbid illnesses. Parent management training is effective for treating psychological problems related to irritability, but its efficacy in treating irritability should be tested rigorously, as should novel mechanism-informed interventions (e.g., those targeting exposure to frustration). Associations between irritability and suicidality and the impact of cultural context are important, underresearched topics. Analyses of large, diverse longitudinal samples that extend into adulthood are needed. Data from both animal and human research indicate that aberrant responses to frustration and threat are central to the pathophysiology of irritability, revealing important translational opportunities.

10 Lessons Learned in Launching a Division-Wide Measurement-Based Care Initiative.

Mental health problems are a major source of morbidity and mortality for children and adolescents, affecting 15% to 20% of those under 18 years of age in the US.1 Half of all mental health conditions start by age 14 years, although most cases remain undetected and untreated.2 Despite knowing much about mental health conditions affecting children, many speculate that the lack of standardized approaches to patient care contribute to poor outcomes, including substantial diagnostic variation, few remissions, risk for relapse or recidivism, and, ultimately, greater mortality due to an inability to accurately predict who will make a suicide attempt.3-5 Studies support this over-reliance on the "art of medicine" (ie, subjective judgment without use of standardized measures), finding that only 17.9% of psychiatrists and 11.1% of psychologists in the US routinely administer symptom rating scales to their patients, despite studies suggesting that when using clinical judgment alone, mental health providers detect deterioration for only 21.4% of patients.4.

Neural activation to peer acceptance and rejection in relation to concurrent and prospective depression risk in adolescent and pre-adolescent girls.

Neurobiological sensitivity to peer interactions is a proposed marker of risk for adolescent depression. We investigated neural response to peer rejection and acceptance in relation to concurrent and prospective depression risk in adolescent and pre-adolescent girls. Participants were 76 girls (Mage=13, 45% racial/ethnic minorities) varying in depression risk: 22 with current major depressive disorder (MDD), 30 at High Risk for MDD based on parental history, and 24 at Low Risk with no psychiatric history. Girls participated in the Chatroom-Interact task-involving rejection and acceptance feedback from fictitious peers-while undergoing functional magnetic resonance neuroimaging. Activation in response to peer rejection and acceptance was extracted from regions of interest. Depressive symptoms were assessed at 6- and 12-month follow-up. Girls with MDD showed blunted left subgenual anterior cingulate response to acceptance versus girls in High and Low Risk groups. Girls in the High Risk group showed greater right temporo-parietal junction (rTPJ) and right anterior insula (AI) activation to both acceptance and rejection versus girls in the MDD (rTPJ) and Low Risk (rTPJ, AI) groups. Greater rTPJ response to rejection was associated with fewer depressive symptoms at 12-months and mediated the association between High Risk group status and 12-month depressive symptoms; greater rTPJ response to acceptance mediated the association between High Risk and increased 12-month depressive symptoms. Our finding of associations between altered neural response to peer interactions and concurrent and prospective depression risk/resilience highlights the importance of neural underpinnings of social cognition as risk and compensatory adaptations along the pathway to depression.

Systematic Review: White Matter Microstructural Organization in Adolescents With Depression.

Objective: A growing body of literature has focused on the neural mechanisms of depression. Our goal was to conduct a systematic review on the white matter microstructural differences in adolescents with depressive disorders vs adolescents without depressive disorders. Method: We searched PubMed and PsycINFO for publications on August 3, 2022 (original search conducted in July 2021). The review was registered on PROSPERO (registration number: CRD42021268200), and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed. Eligible studies were original research papers comparing diffusion tensor/spectrum imaging findings in adolescents with vs without depression (originally ages 12-19 years, later expanded to 11-21 years). Studies were excluded if they focused on depression exclusively in the context of another condition, used only dimensional depressive symptom assessment(s), or used the same dataset as another included publication. Results: The search yielded 575 unique records, of which 14 full-text papers were included (824 adolescents with depression and 686 without depression). The following white matter regions showed significant differences in fractional anisotropy in at least 3 studies: uncinate fasciculus, cingulum, anterior corona radiata, inferior fronto-occipital fasciculus, and corpus callosum (genu and body). Most studies reported decreased, rather than increased, fractional anisotropy in adolescents with depression. Limitations include the possibility for selective reporting bias and risk of imprecision, given the small sample sizes in some studies. Conclusion: Our systematic review suggests aberrant white matter microstructure in limbic-cortical-striatal-thalamic circuits, and the corpus callosum, in adolescents with depression. Future research should focus on developmental trajectories in depression, identifying sources of heterogeneity and integrating findings across imaging modalities.