Familial risk for bipolar I disorder is associated with erythrocyte omega-3 polyunsaturated fatty acid deficits in youth with attention-deficit hyperactivity disorder.

Although attention-deficit/hyperactivity disorder (ADHD) and a family history of bipolar I disorder (BD) increase the risk for developing BD, associated pathoetiological mechanisms remain poorly understood. One candidate risk factor is a neurodevelopmental deficiency in omega-3 polyunsaturated fatty acids, including eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). This study investigated erythrocyte EPA+DHA biostatus in psychostimulant-free ADHD youth with ('high-risk', HR) and without ('low-risk', LR) a first-degree relative with BD, and healthy controls (HC). Erythrocyte EPA+DHA composition was determined by gas chromatography, and symptom ratings were performed. A total of n = 123 (HR, n = 41; LR, n = 42; HC, n = 40) youth (mean age: 14.4 ± 2.5 years) were included in the analysis. Compared with HC, erythrocyte EPA+DHA composition was significantly lower in HR (-13%) but not LR (-3%), and there was a trend for HR to be lower than LR (-11%). Both HR and LR differed significantly from HC on all symptom ratings. HR had greater ADHD hyperactivity/impulsive symptom severity, manic symptom severity, and higher parent-reported ratings of internalization, externalization, and dysregulation, compared with LR. ADHD youth with a BD family history exhibit erythrocyte EPA+DHA deficits and a more severe clinical profile, including greater manic and dysregulation symptoms, compared with ADHD youth without a BD family history.

Fish oil supplementation alters emotion-generated corticolimbic functional connectivity in depressed adolescents at high-risk for bipolar I disorder: A 12-week placebo-controlled fMRI trial.

OBJECTIVE: To evaluate the effects of fish oil (FO), a source of the omega-3 polyunsaturated fatty acids (n-3 PUFA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), on emotion-generated corticolimbic functional connectivity in depressed youth at high risk for developing bipolar I disorder. METHODS: Thirty-nine antidepressant-free youth with a current depressive disorder diagnosis and a biological parent with bipolar I disorder were randomized to 12-week double-blind treatment with FO or placebo. At baseline and endpoint, fMRI (4 Tesla) scans were obtained while performing a continuous performance task with emotional and neutral distractors (CPT-END). Seed-to-voxel functional connectivity analyses were performed using bilateral orbitofrontal cortex (OFC) and amygdala (AMY) seeds. Measures of depression, mania, global symptom severity, and erythrocyte fatty acids were obtained. RESULTS: Erythrocyte EPA+DHA composition increased significantly in the FO group (+47%, p ≤ 0.0001) but not in the placebo group (-10%, p = 0.11). Significant group by time interactions were found for functional connectivity between the left OFC and the left superior temporal gyrus (STG) and between the right AMY and right inferior temporal gyrus (ITG). OFC-STG connectivity increased in the FO group (p = 0.0001) and decreased in the placebo group (p = 0.0019), and AMY-ITG connectivity decreased in the FO group (p = 0.0014) and increased in the placebo group (p < 0.0001). In the FO group, but not placebo group, the decrease in AMY-ITG functional connectivity correlated with decreases in Childhood Depression Rating Scale-Revised and Clinical Global Impression-Severity Scale scores. CONCLUSIONS: In depressed high-risk youth FO supplementation alters emotion-generated corticolimbic functional connectivity which correlates with changes in symptom severity ratings.

A preliminary study of the effects of mindfulness-based cognitive therapy on structural brain networks in mood-dysregulated youth with a familial risk for bipolar disorder.

BACKGROUND: Mindfulness-based cognitive therapy for children (MBCT-C), as a psychotherapeutic intervention, has been shown to be effective for treating mood dysregulation (MD). While previous neuroimaging studies of MD have reported both pre-treatment structural and functional alterations, the effects of MBCT-C on brain morphological network organisation has not been investigated. METHODS: We investigated brain morphological network organisation in 10 mood-dysregulated youth with familial risk for bipolar disorder and 15 matched healthy comparison youth (HC). Effects of 12 weeks of MBCT-C were examined in the mood-dysregulated youth. Topological properties of brain networks used for analyses were constructed based on morphological similarities in regional grey matter using a graph-theory approach using MRI data. RESULTS: At baseline, compared with the HC group, the mood-dysregulated group exhibited increased global efficiency (Eglob ), decreased path length (Lp ), and abnormal nodal properties, mainly in the limbic system. Right temporal pole alterations at baseline predicted change in Child and Adolescent Mindfulness Measure scores after treatment. The mood-dysregulated group showed significant decreases in both the Eglob and Lp metrics after MBCT-C, suggesting an improved capacity for optimal information processing. Changes in Lp were correlated with changes in Emotion Regulation Checklist scores. Our results show significant topological alterations in the mood-dysregulated group as compared to controls at baseline. After MBCT-C, disrupted topological properties in the mood-dysregulated group were significantly reduced. CONCLUSION: MBCT-C may facilitate clinically meaningful changes in the brain structural network in mood-dysregulated individuals.

Emotion-Related Network Reorganization Following Fish Oil Supplementation in Depressed Bipolar Offspring: An fMRI Graph-Based Connectome Analysis.

INTRODUCTION: Mood disorders are associated with fronto-limbic structural and functional abnormalities and deficits in omega-3 polyunsaturated fatty acids including eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Emerging evidence also suggests that n-3 PUFA, which are enriched in fish oil, promote cortical plasticity and connectivity. The present study performed a graph-based connectome analysis to investigate the role of n-3 PUFA in emotion-related network organization in medication-free depressed adolescent bipolar offspring. METHODS: At baseline patients (n = 53) were compared with healthy controls (n = 53), and patients were then randomized to 12-week double-blind treatment with placebo or fish oil. At baseline and endpoint, erythrocyte EPA+DHA levels were measured and fMRI scans (4 Tesla) were obtained while performing a continuous performance task with emotional and neutral distractors (CPT-END). Graph-based analysis was used to characterize topological properties of large-scale brain network organization. RESULTS: Compared with healthy controls, patients exhibited lower erythrocyte EPA+DHA levels (p = 0.0001), lower network clustering coefficients (p = 0.029), global efficiency (p = 0.042), and lower node centrality and connectivity strengths in frontal-limbic regions (p<0.05). Compared with placebo, 12-week fish oil supplementation increased erythrocyte EPA+DHA levels (p<0.001), network clustering coefficient (p = 0.005), global (p = 0.047) and local (p = 0.023) efficiency, and node centralities mainly in temporal regions (p<0.05). LIMITATIONS: The duration of fish oil supplementation was relatively short and the sample size was relatively small. CONCLUSIONS: These findings provide preliminary evidence that abnormalities in emotion-related network organization observed in depressed high-risk youth may be amenable to modification through fish oil supplementation.

Network-level functional topological changes after mindfulness-based cognitive therapy in mood dysregulated adolescents at familial risk for bipolar disorder: a pilot study.

BACKGROUND: Given that psychopharmacological approaches routinely used to treat mood-related problems may result in adverse outcomes in mood dysregulated adolescents at familial risk for bipolar disorder (BD), Mindfulness-Based Cognitive Therapy for Children (MBCT-C) provides an alternative effective and safe option. However, little is known about the brain mechanisms of beneficial outcomes from this intervention. Herein, we aimed to investigate the network-level neurofunctional effects of MBCT-C in mood dysregulated adolescents. METHODS: Ten mood dysregulated adolescents at familial risk for BD underwent a 12-week MBCT-C intervention. Resting-state functional magnetic resonance imaging (fMRI) was performed prior to and following MBCT-C. Topological metrics of three intrinsic functional networks (default mode network (DMN), fronto-parietal network (FPN) and cingulo-opercular network (CON)) were investigated respectively using graph theory analysis. RESULTS: Following MBCT-C, mood dysregulated adolescents showed increased global efficiency and decreased characteristic path length within both CON and FPN. Enhanced functional connectivity strength of frontal and limbic areas were identified within the DMN and CON. Moreover, change in characteristic path length within the CON was suggested to be significantly related to change in the Emotion Regulation Checklist score. CONCLUSIONS: 12-week MBCT-C treatment in mood dysregulated adolescents at familial risk for BD yield network-level neurofunctional effects within the FPN and CON, suggesting enhanced functional integration of the dual-network. Decreased characteristic path length of the CON may be associated with the improvement of emotion regulation following mindfulness training. However, current findings derived from small sample size should be interpreted with caution. Future randomized controlled trials including larger samples are critical to validate our findings.

Mindfulness-based cognitive therapy for children and adolescents with anxiety disorders at-risk for bipolar disorder: A psychoeducation waitlist controlled pilot trial.

AIM: Previous studies suggest that Mindfulness-Based Cognitive Therapy for Children (MBCT-C) is feasible and may improve anxiety and emotion regulation in youth with anxiety disorders at-risk for bipolar disorder. However, controlled studies are warranted to replicate and extend these findings. METHODS: In the current study, 24 youth with anxiety disorders who have at least one parent with bipolar disorder participated in a MBCT-C treatment period (n = 24; Mage = 13.6, 75% girls, 79% White) with a subset also participating in a prior psychoeducation waitlist control period (n = 19 Mage = 13.8, 68% girls, 84% White). Participants in both the waitlist and MBCT-C periods completed independently-rated symptom scales at each time point. Participants in the waitlist period received educational materials 12 weeks prior to the beginning of MBCT-C. RESULTS: There were significantly greater improvements in overall clinical severity in the MBCT-C period compared to the waitlist period, but not in clinician- and child-rated anxiety, emotion regulation or mindfulness. However, increases in mindfulness were associated with improvements in anxiety and emotion regulation in the MBCT-C period, but not the waitlist period. CONCLUSIONS: Findings suggest that MBCT-C may be effective for improving overall clinical severity in youth with anxiety disorders who are at-risk for bipolar disorder. However, waitlist controlled designs may inflate effect sizes so interpret with caution. Larger studies utilizing prospective randomized controlled designs are warranted.

Neurophysiological effects of multiple mood episodes in bipolar disorder.

OBJECTIVES: Bipolar disorder is marked by progressive symptomatic changes, which have been linked with episode-related structural findings-particularly in the prefrontal cortex. However, few studies have examined neurofunctional and neurochemical effects of disease burden. In this study, we compared first- and multi-episode bipolar individuals. We hypothesized that the latter would demonstrate evidence of neurophysiological differences consistent with a model of progressive functional degradation of these networks. METHODS: First- and multi-episode manic bipolar subjects participated in functional magnetic resonance imaging (fMRI) including a continuous performance task with emotional distractors, and in single-voxel (1 H) magnetic resonance spectroscopy (MRS). A priori fMRI regions-of-interest (ROI) included structures comprising prefrontal-striatal-amygdala networks; (1 H)MRS voxels were placed within bilateral ventrolateral prefrontal (VLPFC) and anterior cingulate cortex (ACC). Both ROI and voxel-based brain activation in response to emotional stimuli, and neurochemical concentrations derived from (1 H)MRS were compared across bipolar groups. RESULTS: Multi-episode bipolar subjects showed relatively lower regional activation across prefrontal-striatal-amygdala networks, including bilateral VLPFC, orbitofrontal cortex, ACC, putamen, caudate, and amygdala. Exploratory whole-brain, voxel-based analysis suggested additional areas of lower activation extending into Brodmann area 22, posterior parietal regions, and right thalamus. Glutamate and N-acetylaspartate (NAA) concentrations were also relatively lower in the ACC of multi-episode subjects. CONCLUSIONS: Disease burden, exemplified by multiple affective episodes is associated with evidence of widespread decrements in affective network activity. Lower ACC NAA concentration is similarly consistent with a model of progressive functional deficits. These findings support the functional significance of previously observed progressive structural changes throughout these regions.

Cardiometabolic risks and omega-3 index in recent-onset bipolar I disorder.

OBJECTIVES: The aims of the present study were to characterize cardiometabolic risk factors in a cohort of bipolar disorder patients with limited exposure to psychotropic medications, and to evaluate their associations with mood symptoms and omega-3 polyunsaturated fatty acid (PUFA) blood levels. METHODS: Cardiometabolic risk assessments were compared in individuals with bipolar I disorder experiencing a first manic or mixed episode or an early depressive episode (n=117) and healthy subjects (n=56). Patients were medication free at assessment and had no or limited exposure to mood-stabilizer or antipsychotic medications prior to the current admission. Associations among cardiometabolic parameters and Clinical Global Impression-Severity scale (CGI-S), manic (Young Mania Rating Scale [YMRS]), and depressive (Hamilton Depression Rating Scale [HDRS]) symptom ratings were evaluated within the bipolar group. RESULTS: Following adjustment for demographic variables (i.e., age, gender, and parental education), significantly higher fasting triglyceride levels were observed in the bipolar group compared to the healthy group (121.7 mg/dL vs 87.0 mg/dL; P<.01). There were no clear trends for other metabolic indicators, including blood pressure, body mass index, and fasting glucose. Nineteen percent of the bipolar group and 6% of the healthy group met the criteria for metabolic syndrome (P=.23). The omega-3 index was lower in the bipolar group (3.4% vs 3.9%; P<.01). Within the bipolar group, no associations were found between the cardiometabolic parameters and CGI-S, YMRS, and HDRS symptom ratings. CONCLUSIONS: Recent-onset medication-free bipolar disorder is associated with higher triglyceride levels. These findings are suggestive of early metabolic dysregulation prior to long-term psychotropic medication exposure. Lower omega-3 PUFA levels in individuals with bipolar I disorder represent a potential therapeutic target for additional investigation.

Suicidality in psychiatrically hospitalized children and adolescents: Demographics, treatment, and outcome.

BACKGROUND: Despite the high prevalence of suicidality in psychiatrically hospitalized youth, its risk factors and impact on inpatient psychopharmacologic treatment are unknown. We identified characteristics associated with suicidality in psychiatrically hospitalized youth and determined the association of suicidality with subsequent psychopharmacologic interventions. METHODS: Medical records from consecutive psychiatric admissions to a large, acute care, urban, pediatric hospital were analyzed retrospectively (N = 1,309). Demographic, clinical, and treatment-related features of suicidal and nonsuicidal youth were characterized. Logistic regression identified predictors of suicidality, and multiple comparison analyses evaluated the association between suicidality and changes to antidepressant prescribing during inpatient course. RESULTS: Compared with nonsuicidal patients, inpatients who were suicidal were more likely to have a mood disorder or posttraumatic stress disorder, as well as Cannabis and alcohol use, were more commonly girls, and at least 13 years of age (all P ≤ .05). Hospitalization was shorter for suicidal patients, was more likely to be associated with antidepressant treatment (P ≤ .001), and among suicidal patients prescribed antidepressants at the time of admission, was associated with a greater likelihood of changing antidepressant treatment compared with nonsuicidal inpatients (P ≤ .05). CONCLUSIONS: These findings reveal differences between suicidal and nonsuicidal psychiatrically hospitalized youth and suggest that suicidality is associated with specific pharmacologic treatment approaches within this population.

Neural Function Before and After Mindfulness-Based Cognitive Therapy in Anxious Adolescents at Risk for Developing Bipolar Disorder.

OBJECTIVE: We sought to evaluate the neurophysiology of mindfulness-based cognitive therapy for children (MBCT-C) in youth with generalized, social, and/or separation anxiety disorder who were at risk for developing bipolar disorder. METHODS: Nine youth (mean age: 13 ± 2 years) with a generalized, social, and/or separation anxiety disorder and a parent with bipolar disorder completed functional magnetic resonance imaging (fMRI) while performing a continuous processing task with emotional and neutral distractors (CPT-END) prior to and following 12 weeks of MBCT-C. RESULTS: MBCT-C was associated with increases in activation of the bilateral insula, lentiform nucleus, and thalamus, as well as the left anterior cingulate while viewing emotional stimuli during the CPT-END, and decreases in anxiety were correlated with change in activation in the bilateral insula and anterior cingulate during the viewing of emotional stimuli (p < 0.05, uncorrected; p < 0.005 corrected; cluster size, 37 voxels). CONCLUSIONS: MBCT-C treatment in anxious youth with a familial history of bipolar disorder is associated with increased activation of brain structures that subserve interoception and the processing of internal stimuli-functions that are ostensibly improved by this treatment.

Mindfulness-based cognitive therapy for youth with anxiety disorders at risk for bipolar disorder: a pilot trial.

AIM: Children and adolescents with bipolar parents have an elevated risk for anxiety disorders. However, antidepressant medications commonly used to treat symptoms of anxiety may accelerate the onset of mania in these already at-risk youth. Therefore, studies evaluating innovative non-pharmacologic treatments for anxiety in this population are urgently needed. METHODS: Subjects participated in 12 weekly sessions of mindfulness-based cognitive therapy for children (MBCT-C), a manualized group psychotherapeutic intervention utilizing cognitive behavioural principles and mindfulness exercises to increase regulation of attention and non-judgmental acceptance of present moment thoughts, emotions and experiences. Independent raters administered symptoms rating scales prior to each treatment session. Spearman correlations and paired-samples signed rank tests were used to examine outcomes. After-intervention surveys and session transcripts were reviewed to assess feasibility and acceptability of the intervention. RESULTS: Participants included 10 youth (meanage = 13.2; 80% girls; 40% biracial) with generalized, social and/or separation anxiety disorders, and a parent with bipolar disorder. Clinician-rated anxiety was significantly reduced after intervention (meanbefore = 11.1; meanafter = 4.3; P < 0.01), as well as youth-rated trait anxiety (P = 0.03). Parent-rated emotion regulation significantly increased from before to after intervention (P = 0.05). Increases in mindfulness were associated with decreases in anxiety (P = 0.03). Finally, children and parents/guardians reported high levels of feasibility, acceptability and usefulness of the intervention. CONCLUSION: Findings support the feasibility, acceptability and preliminary efficacy of MBCT-C for treating anxiety in youth at risk for bipolar disorder. Future controlled and larger studies are needed to confirm these preliminary findings.

Effects of fish oil supplementation on prefrontal metabolite concentrations in adolescents with major depressive disorder: a preliminary 1H MRS study.

OBJECTIVE: To use proton magnetic resonance spectroscopy ((1)H MRS) to investigate the effects of fish oil (FO) supplementation on cortical metabolite concentrations in adolescents with major depressive disorder (MDD). METHODS: Metabolite concentrations were determined by (1)H MRS in the anterior cingulate cortex and bilateral dorsolateral prefrontal cortex (DLPFC) of adolescents with MDD before and following 10-week open-label supplementation with low (2.4 g/day, n = 7) or high (16.2 g/day, n = 7) dose FO. Depressive symptom severity scores and erythrocyte fatty acid levels were also determined. RESULTS: Baseline erythrocyte eicosapentaenoic acid (EPA) composition was positively correlated, and arachidonic acid (AA) and the AA/EPA ratio were inversely correlated, with choline (Cho) concentrations in the right DLPFC. Docosahexaenoic acid (DHA) composition was inversely correlated with myo-inositol (mI) concentrations in the left DLPFC. Erythrocyte EPA and DHA composition increased, and AA decreased, significantly following low-dose and high-dose FO supplementation. In the intent-to-treat sample, depressive symptom severity scores decreased significantly in the high-dose group (-40%, P < 0.0001) and there was a trend in the low-dose group (-20%, P = 0.06). There were no significant baseline-endpoint changes in metabolite levels in each voxel. In the low-dose group there were changes with large effect sizes, including a decrease in mI in the left DLPFC (-12%, P = 0.18, d = 0.8) and increases in glutamate + glutamine (Glx) (+12%, P = 0.19, d = 0.8) and Cho (+15%, P = 0.08, d = 1.2) in the right DLPFC. In the high-dose group, there was a trend for increases in Cho in the right DLPFC (+10%, P = 0.09, d = 1.2). DISCUSSION: These preliminary data suggest that increasing the LCn-3 fatty acid status of adolescent MDD patients is associated with subtle changes in Glx, mI, and Cho concentrations in the DLPFC that warrant further evaluation in a larger controlled trial.

Correlations of inflammatory gene pathways, corticolimbic functional activities, and aggression in pediatric bipolar disorder: a preliminary study.

The mechanisms underlying aggression in adolescents with bipolar disorder have been poorly understood. The present study has investigated the associations among TNF gene expressions, functional brain activations under the frustrative non-reward task, and aggression in adolescents with bipolar disorder. Baseline gene expressions and aggressive tendencies were measured with the RNA-sequencing and Brief Rating of Aggression by Children and Adolescents (BRACHA), respectively. Our results show that activity levels of left subgenual anterior cingulate gyrus (ACG), right amygdala, left Brodmann area 10 (orbitofrontal cortex), and right thalamus were inversely correlated with BRACHA scores and were activated with frustrative non-reward during the affective Posner Task. In addition, 11 TNF related gene expressions were significantly correlated with activation of amygdala or ACG during the affective Posner Task. Three TNF gene expressions were inversely correlated with BRACHA score while one TNF gene (TNFAIP3) expression was positively correlated with BRACHA score. Therefore, TNF-related inflammatory cytokine genes may play a role in neural activity associated with frustrative non-reward and aggressive behaviors in pediatric bipolar disorder.

Detection and Treatment of Long-Chain Omega-3 Fatty Acid Deficiency in Adolescents with SSRI-Resistant Major Depressive Disorder.

Residual depressive symptoms are commonly observed in adolescents with major depressive disorder (MDD) following treatment with selective serotonin reuptake inhibitors (SSRIs). This study combined a case-control analysis and an open-label fish oil (FO) trial to investigate the relationship between long-chain omega-3 (LCn-3) fatty acid status and residual depressive symptoms in SSRI-resistant adolescent MDD patients. Baseline erythrocyte docosahexaenoic acid (DHA)(-28%, p=0.0003), but not eicosapentaenoic acid (EPA)(-18%, p=0.2), was significantly lower in patients (n=20) compared with healthy controls (n=20). Patients receiving 10-week low-dose (2.4 g/d, n=7) and high-dose (16.2 g/d, n=7) FO exhibited significant increases in erythrocyte EPA and DHA composition. In the intent-to-treat sample, depressive symptoms decreased significantly in the high-dose group (n=7, -40%, p<0.0001), and there was a trend in the low-dose group (n=10, -20%, p=0.06). Symptom remission was observed in 40% of patients in the low-dose group and 100% of patients in the high-dose group. There were no significant changes in vital signs and adverse events were rated as mild or moderate in severity. These preliminary findings demonstrate that adolescents with SSRI-resistant depression exhibit robust DHA deficits, and suggest that adjunctive FO supplementation is well-tolerated and effective for increasing LCn-3 fatty acid status and augmenting SSRI antidepressant effects.

Docosahexaenoic acid supplementation increases prefrontal cortex activation during sustained attention in healthy boys: a placebo-controlled, dose-ranging, functional magnetic resonance imaging study.

BACKGROUND: Emerging evidence suggests that docosahexaenoic acid (DHA, 22:6n-3), the principal omega-3 (n-3) fatty acid in brain gray matter, positively regulates cortical metabolic function and cognitive development. However, the effects of DHA supplementation on functional cortical activity in human subjects are unknown. OBJECTIVE: The objective was to determine the effects of DHA supplementation on functional cortical activity during sustained attention in human subjects. DESIGN: Healthy boys aged 8-10 y (n = 33) were randomly assigned to receive placebo or 1 of 2 doses of DHA (400 or 1200 mg/d) for 8 wk. Relative changes in cortical activation patterns during sustained attention at baseline and endpoint were determined by functional magnetic resonance imaging. RESULTS: At 8 wk, erythrocyte membrane DHA composition increased significantly from baseline in subjects who received low-dose (by 47%) or high-dose (by 70%) DHA but not in those who received placebo (-11%). During sustained attention, both DHA dose groups had significantly greater changes from baseline in activation of the dorsolateral prefrontal cortex than did the placebo group, and the low-dose and high-dose DHA groups had greater decreases in the occipital cortex and cerebellar cortex, respectively. Relative to low-dose DHA, high-dose DHA resulted in greater decreases in activation of bilateral cerebellum. The erythrocyte DHA composition was positively correlated with dorsolateral prefrontal cortex activation and was inversely correlated with reaction time, at baseline and endpoint. CONCLUSION: Dietary DHA intake and associated elevations in erythrocyte DHA composition are associated with alterations in functional activity in cortical attention networks during sustained attention in healthy boys. This trial was registered at clinicaltrials.gov as NCT00662142.

The functional neuroanatomy of bipolar disorder.

In this manuscript, research articles using functional magnetic resonance imaging (fMRI) to study adult patients with bipolar disorder were reviewed. The findings from these studies identify altered brain activation in five regions in cortico-limbic pathways responsible for emotional regulation: portions of the prefrontal cortex; anterior cingulate cortex; amygdala; thalamus; and striatum. The most consistent findings were overactivation of amygdala, striatum, and thalamus. Findings in prefrontal cortex were less consistent, but most studies also showed increased activation in ventrolateral and dorsolateral prefrontal cortical areas. Excessive activation in brain regions associated with emotional regulation may contribute to the affective symptoms of bipolar disorder. However, there are several important limitations in this body of research. Even when similar tasks were used, brain activation was often discrepant among studies. Most fMRI studies examined small samples (ten or fewer bipolar subjects) limiting statistical power. Additionally, most studies were confounded by patients taking psychotropic medications. Nonetheless, from this work an anterior limbic over-activation model of bipolar disorder is emerging.

Neuroanatomical characterization of child offspring of bipolar parents.

OBJECTIVE: To examine structural differences in selected anterior limbic brain regions between at-risk children of parents with bipolar I disorder and children with healthy parents. We hypothesized that at-risk (AR) children would exhibit abnormalities in brain regions that are involved in mood regulation. METHOD: Children (8-12 years old) of parents with bipolar I disorder (AR children, n = 21) and of parents without any DSM-IV Axis I disorder (healthy controls, n = 24) were evaluated using diagnostic assessments and brain magnetic resonance imaging. Morphometric analyses were used to examine group differences in the prefrontal cortical, thalamic, striatal, and amygdalar volumes. RESULTS: Nine (43%) of the AR children met DSM-IV-TR criteria for a nonbipolar mood disorder at the time of assessment. AR and healthy control children did not demonstrate statistically significant differences across regions of interest (Wilks lambda =.86, F4,39 = 1.64, p = .18; effect size, f = 0.19). Post hoc analyses of covariance showed the largest relative effect size was contributed by the prefrontal cortex (f = 0.26). CONCLUSIONS: Eight- to 12-year-old children with a familial risk for mania do not exhibit any statistically significant volumetric differences in the prefrontal cortex, thalamus, striatum, or amygdala as compared with age-matched children of parents without any psychopathology. Longitudinal studies examining whether structural changes over time may be associated with vulnerability for developing subsequent bipolar disorder are needed to clarify the underlying pathophysiology of this disorder.

Voxel-based study of structural changes in first-episode patients with bipolar disorder.

BACKGROUND: Although morphometric studies of bipolar disorder (BD) suggest that neurofunctional abnormalities reflect underlying structural changes, it remains unclear whether abnormalities are present at illness onset or reflect disease progression. Previous voxel-based morphometry (VBM) findings suggest that ventrolateral prefrontal cortex (VLPFC) changes develop over time, whereas morphologic abnormalities elsewhere in the anterior limbic network (ALN) are present early in BD. In this study, we used VBM to explore structural brain changes in first-episode bipolar patients. METHODS: First-episode bipolar (n = 33) and healthy (n = 33) subjects underwent magnetic resonance imaging. Images were normalized and compared on a voxel-by-voxel basis. RESULTS: Bipolar subjects showed no change in VLPFC density or volume. We observed increased volume in left thalamus and fusiform and cerebellum bilaterally; increased gray matter density in anterior cingulate and posterior parietal structures; and increased gray matter volume and density in middle/superior temporal and posterior cingulate gyri. No areas of decreased volume or density were observed. CONCLUSIONS: These data indicate that structural changes are absent from VLPFC early in the course of BD. Morphologic abnormalities are present in other portions of the ALN and in structures previously observed to mediate neurofunctional changes in BD, suggesting that dysfunctional neuronal proliferation or pruning may occur in bipolar patients.

Magnetic resonance imaging analysis of amygdala and other subcortical brain regions in adolescents with bipolar disorder.

OBJECTIVES: Few studies have examined the abnormalities that underlie the neuroanatomy of bipolar disorder in youth. The aim of this study was to evaluate brain regions that are thought to modulate mood utilizing quantitative analyses of thin-slice magnetic resonance imaging (MRI) scans of adolescents with bipolar disorder. We hypothesized that adolescents with bipolar disorder would exhibit abnormalities in brain regions that are involved in the regulation of mood including the amygdala, globus pallidus, caudate, putamen, and thalamus. METHODS: Bipolar adolescents (n = 23) and healthy subjects (n = 20) matched for age, race, sex, socioeconomic status, IQ, education and Tanner stage, were evaluated using the Washington University at St Louis Kiddie-Schedule for Affective Disorders and Schizophrenia (WASH-U K-SADS). Contiguous 1 mm axial T1-weighted MRI slices were obtained using a GE 1.5 T MR scanner. Regions of interest (ROI) included total cerebral volume, amygdala, globus pallidus, caudate, putamen, and thalamus. RESULTS: Total cerebral volume was smaller in bipolar adolescents than in healthy adolescents. A MANCOVA revealed a significant group difference in overall ROI volumes after adjusting for total cerebral volume. Specifically, adolescents with bipolar disorder exhibited smaller amygdala and enlarged putamen compared with healthy subjects. CONCLUSIONS: Our findings indicate that adolescents with bipolar disorder exhibit abnormalities in some of the brain regions that are thought to be involved in the regulation of mood. Additional structural and functional neuroimaging investigations of children, adolescents, and adults with bipolar disorder are necessary to clarify the role of these brain regions in the neurophysiology of adolescent bipolar disorder.