Gray matter changes and cognitive predictors of 2-year follow-up abnormalities in early-onset first-episode psychosis

Neural dysfunction underlying working memory processing at different stages of the illness course in schizophrenia: a comparative meta-analysis

Schizophrenia, as a chronic and persistent disorder, exhibits working memory deficits across various stages of the disorder, yet the neural mechanisms underlying these deficits remain elusive with inconsistent neuroimaging findings. We aimed to compare the brain functional changes of working memory in patients at different stages: clinical high risk, first-episode psychosis, and long-term schizophrenia, using meta-analyses of functional magnetic resonance imaging studies. Following a systematic literature search, 56 whole-brain task-based functional magnetic resonance imaging studies (15 for clinical high risk, 16 for first-episode psychosis, and 25 for long-term schizophrenia) were included. The separate and pooled neurofunctional mechanisms among clinical high risk, first-episode psychosis, and long-term schizophrenia were generated by Seed-based d Mapping toolbox. The clinical high risk and first-episode psychosis groups exhibited overlapping hypoactivation in the right inferior parietal lobule, right middle frontal gyrus, and left superior parietal lobule, indicating key lesion sites in the early phase of schizophrenia. Individuals with first-episode psychosis showed lower activation in left inferior parietal lobule than those with long-term schizophrenia, reflecting a possible recovery process or more neural inefficiency. We concluded that SCZ represent as a continuum in the early stage of illness progression, while the neural bases are inversely changed with the development of illness course to long-term course.

Shared and Distinct Neurobiological Bases of Bipolar Disorder and Attention-Deficit/Hyperactivity Disorder in Children and Adolescents: A Comparative Meta-Analysis of Structural Abnormalities

OBJECTIVE

Pediatric bipolar disorder (PBD) and attention-deficit/hyperactivity disorder (ADHD) frequently co-occur and share dysfunctions in affective and cognitive domains. As the neural substrates underlying their overlapping and dissociable symptomatology have not been well delineated, a meta-analysis of whole-brain voxel-based morphometry studies in PBD and ADHD was conducted.

METHOD

A systematic literature search was performed in PubMed, Web of Science, and Embase. The seed-based d mapping toolbox was used to identify altered clusters of PBD or ADHD and obtain their conjunctive and comparative abnormalities. Suprathreshold patterns were subjected to large-scale network analysis to identify affected brain networks.

RESULTS

The search revealed 10 PBD studies (268 patients) and 32 ADHD studies (1,333 patients). Decreased gray matter volumes in the right insula and anterior cingulate cortex relative to typically developing individuals were conjunctive in PBD and ADHD. Reduced volumes in the right inferior frontal gyrus, left orbitofrontal cortex, and hippocampus were more substantial in PBD, while decreased volumes in the left precentral gyrus, left inferior frontal gyrus, and right superior frontal gyrus were more pronounced in ADHD. Neurodevelopmental effects modulated patterns of the left hippocampus in PBD and those of the left inferior frontal gyrus in ADHD.

CONCLUSION

These findings suggest that PBD and ADHD are characterized by both common and distinct patterns of gray matter volume alterations. Their overlapping abnormalities may represent a transdiagnostic problem of attention and emotion regulation shared by PBD and ADHD, whereas the disorder-differentiating substrates may contribute to the relative differences in cognitive and affective features that define the 2 disorders.

PLAIN LANGUAGE SUMMARY

Pediatric bipolar disorder (BD) and attention-deficit/hyperactivity disorder (ADHD) frequently co-occur, with overlapping changes in emotional and cognitive functioning. This meta-analysis summarizes findings from 10 articles on BD and 32 articles on ADHD to identify similarities and differences in brain structure between youth with BD and youth with ADHD. The authors found that both disorders share decreased gray matter volumes in the right insula and anterior cingulate cortex, which play important roles in emotion processing and attention, respectively. Youth with BD had decreased gray matter volume in the right inferior frontal gyrus, left orbitofrontal gyrus, and left hippocampus, while youth with ADHD had decreased volumes in the left precentral gyrus, left inferior frontal gyrus, and right superior frontal gyrus.

STUDY PREREGISTRATION INFORMATION

Structural Brain Abnormalities of Attention-Deficit/Hyperactivity Disorder and Bipolar Disorder in Children/Adolescents: An Overlapping Meta-analysis; https://osf.io; trg4m.

Cognitive predictors of transition and remission of psychosis risk syndrome in a child and adolescent sample: longitudinal findings from the CAPRIS study

Cognitive impairments are proposed as predictors in the differentiation between subjects with psychosis risk syndrome (PRS) who will develop a psychotic disorder (PRS-P) and those who will not (PRS-NP). More in-depth study of the PRS-NP group could contribute to defining the role of cognitive alterations in psychosis. This study aims to analyze cognition of children and adolescents with PRS in terms of their clinical outcome at 18-month follow-up (psychosis, remission, and non-remission) and of determinate predictors of transition to psychosis and remission of PRS. The method is two-site, naturalistic, longitudinal study design, with 98 help-seeking adolescents with PRS and 64 healthy controls (HC). PRS-P (n = 24) and PRS-NP (n = 74) participants were clinically and cognitively assessed at baseline, and when full-blown psychotic disorder had developed or at 18-month follow-up. PRS-P subjects showed lower scores at baseline in processing speed, visuospatial memory, attention, and executive function (cognitive flexibility/processing speed) compared to HC. PRS-NP subjects showed lower baseline scores in verbal working memory and verbal fluency compared to HC. This deficit is also observed in the PRS group of participants still presenting attenuated psychotic symptoms at 18-month follow-up, while PRS subjects in remission showed a similar cognitive profile to HC subjects. Baseline score on processing speed, measured with a coding task, appeared to be a predictive variable for the development of a psychotic disorder. Performance in verbal working memory was predictive of remission in the PRS-NP. Post hoc comparisons indicate the need for careful interpretation of cognitive markers as predictors of psychosis. Cognitive impairments are present in both PRS-P and PRS-NP. Those individuals who recover from PRS show baseline cognitive performance comparable to the HC group. Together with sociodemographic variables, this observation could help in the differentiation of a variety of PRS trajectories in children and adolescents.

Melatonin secretion patterns are associated with cognitive vulnerability and brain structure in bipolar depression

Circadian rhythm disruption is a core symptom of bipolar disorder (BD), also reflected in altered patterns of melatonin release. Reductions of grey matter (GM) volumes are well documented in BD. We hypothesized that levels and timing of melatonin secretion in bipolar depression could be associated with depressive psychopathology and brain GM integrity. The onset of melatonin secretion under dim light conditions (DLMO) and the amount of time between DLMO and midsleep (i.e. phase angle difference; PAD) were used as circadian rhythm markers. To study the time course of melatonin secretion, an exponential curve fitting the melatonin values was calculated, and the slope coefficients (SLP) were obtained for each participant. Significant differences were found between HC and BD in PAD measures and melatonin profiles. Correlations between PAD and depressive psychopathology were identified. Melatonin secretion patterns were found to be associated with GM volumes in the Striatum and Supramarginal Gyrus in BD. Our findings emphasized the role of melatonin secretion role as a biological marker of circadian synchronization in bipolar depression and provided a novel insight for a link between melatonin release and brain structure.

Gray matter alterations in adolescent major depressive disorder and adolescent bipolar disorder

BACKGROUND

Gray matter volume (GMV) alterations in several emotion-related brain areas are implicated in mood disorders, but findings have been inconsistent in adolescents with major depressive disorder (MDD) or bipolar disorder (BD).

METHODS

We conducted a comprehensive meta-analysis of 35 region-of-interest (ROI) and 18 whole-brain voxel-based morphometry (VBM) MRI studies in adolescent MDD and adolescent BD, and indirectly compared the results in the two groups. The effects of age, sex, and other demographic and clinical scale scores were explored using meta-regression analysis.

RESULTS

In the ROI meta-analysis, right putamen volume was decreased in adolescents with MDD, while bilateral amygdala volume was decreased in adolescents with BD compared to healthy controls (HC). In the whole-brain VBM meta-analysis, GMV was increased in right middle frontal gyrus and decreased in left caudate in adolescents with MDD compared to HC, while in adolescents with BD, GMV was increased in left superior frontal gyrus and decreased in limbic regions compared with HC. MDD vs BD comparison revealed volume alteration in the prefrontal-limbic system.

LIMITATION

Different clinical features limit the comparability of the samples, and small sample size and insufficient clinical details precluded subgroup analysis or meta-regression analyses of these variables.

CONCLUSIONS

Distinct patterns of GMV alterations in adolescent MDD and adolescent BD could help to differentiate these two populations and provide potential diagnostic biomarkers.

Gray matter abnormalities and associated familial risk endophenotype in individuals with first-episode bipolar disorder: Evidence from whole-brain voxel-wise meta-analysis

Gray matter abnormalities have been widely reported in individuals with and at familial risk for bipolar disorder (BD). However, inconsistent findings were reported, and whether shared abnormalities exist between at-risk individuals and patients which can represent an endophenotype remained unclear. This meta-analysis aimed at identifying robust patterns of gray matter changes in patients with first-episode BD (FEBD) and associated risk endophenotype of BD. A systematic literature search was performed to identify eligible voxel-based morphometry studies comparing FEBD patients and healthy controls. Findings of included studies were integrated using the Seed-based d Mapping toolbox. Common and distinct patterns of gray matter abnormalities between FEBD patients and unaffected at-risk individuals were explored. A total of 16 VBM studies comparing 411 FEBD patients and 521 controls were included. FEBD patients showed increased gray matter volume in the cerebellum, posterior cingulate cortex and striatum, and decreased gray matter volume in the medial superior frontal gyrus and gyrus rectus. No common abnormalities were identified between FEBD patients and unaffected at-risk individuals. More gray matter loss in the medial superior frontal gyrus and insula were found in FEBD patients relative to unaffected at-risk individuals. These findings revealed robust gray matter abnormalities in the cortico-striato-cerebellar and default mode network regions in FEBD, and implicated that gray matter deficits may not represent a familial risk endophenotype of BD.

Gray Matter Alterations in Pediatric Schizophrenia and Obsessive-Compulsive Disorder: A Systematic Review and Meta-Analysis of Voxel-Based Morphometry Studies

OBJECTIVE

The aim of this study is comparing gray matter alterations in SCZ pediatric patients with those suffering from obsessive-compulsive disorder (OCD) based on a systematic review and an activation likelihood estimation (ALE) meta-analysis.

METHODS

A systematic literature search was performed in PubMed, Elsevier, and China National Knowledge Infrastructure (CNKI). A systematic review and an ALE meta-analysis were performed to quantitatively examine brain gray matter alterations.

RESULTS

Children and adolescents with schizophrenia had decreased gray matter volume (GMV) mainly in the prefrontal cortex (PFC), temporal cortex (such as the middle temporal gyrus and transverse temporal gyrus), and insula, while children and adolescents with OCD mainly had increased GMV in the PFC and the striatum (including the lentiform nucleus and caudate nucleus), and decreased GMV in the parietal cortex.

CONCLUSIONS

Our results suggest that gray matter abnormalities in the PFC may indicate homogeneity between the two diseases. In children and adolescents, structural alterations in schizophrenia mainly involve the fronto-temporal and cortico-insula circuits, whereas those in OCD mainly involve the prefrontal-parietal and the prefrontal-striatal circuits.

A Systematic Review of Cognition-Brain Morphology Relationships on the Schizophrenia-Bipolar Disorder Spectrum

The nature of the relationship between cognition and brain morphology in schizophrenia-spectrum disorders (SSD) and bipolar disorder (BD) is uncertain. This review aimed to address this, by providing a comprehensive systematic investigation of links between several cognitive domains and brain volume, cortical thickness, and cortical surface area in SSD and BD patients across early and established illness stages. An initial search of PubMed and Scopus databases resulted in 1486 articles, of which 124 met inclusion criteria and were reviewed in detail. The majority of studies focused on SSD, while those of BD were scarce. Replicated evidence for specific regions associated with indices of cognition was minimal, however for several cognitive domains, the frontal and temporal regions were broadly implicated across both recent-onset and established SSD, and to a lesser extent BD. Collectively, the findings of this review emphasize the significance of both frontal and temporal regions for some domains of cognition in SSD, while highlighting the need for future BD-related studies on this topic.

Fronto-Parietal Gray Matter Volume Loss Is Associated with Decreased Working Memory Performance in Adolescents with a First Episode of Psychosis

Cognitive maturation during adolescence is modulated by brain maturation. However, it is unknown how these processes intertwine in early onset psychosis (EOP). Studies examining longitudinal brain changes and cognitive performance in psychosis lend support for an altered development of high-order cognitive functions, which parallels progressive gray matter (GM) loss over time, particularly in fronto-parietal brain regions. We aimed to assess this relationship in a subsample of 33 adolescents with first-episode EOP and 47 matched controls over 2 years. Backwards stepwise regression analyses were conducted to determine the association and predictive value of longitudinal brain changes over cognitive performance within each group. Fronto-parietal GM volume loss was positively associated with decreased working memory in adolescents with psychosis (frontal left (B = 0.096, p = 0.008); right (B = 0.089, p = 0.015); parietal left (B = 0.119, p = 0.007), right (B = 0.125, p = 0.015)) as a function of age. A particular decrease in frontal left GM volume best predicted a significant amount (22.28%) of the variance of decreased working memory performance over time, accounting for variance in age (14.9%). No such association was found in controls. Our results suggest that during adolescence, EOP individuals seem to follow an abnormal neurodevelopmental trajectory, in which fronto-parietal GM volume reduction is associated with the differential age-related working memory dysfunction in this group.

Longitudinal grey matter changes following first episode mania in bipolar I disorder: A systematic review

BACKGROUND

While widespread grey matter (GM) changes are seen in bipolar I disorder (BD-I), it is unclear how early in the illness such changes emerge. To date there has been little synthesis of findings regarding longitudinal grey matter changes early in the course of BD-I. We conducted a systematic review to examine the evolution of GM changes in BD-I patients following the first episode of mania (FEM).

METHODS

Following PRISMA guidelines, we conducted a systematic review of studies examining longitudinal changes in GM volume (GMV), cortical thickness and/or surface area in BD-I patients following FEM. We qualitatively synthesized results regarding longitudinal GM changes in BD-I patients.

RESULTS

Fifteen studies met inclusion criteria, all examining GMV changes. Longitudinal ACC volume decrease following FEM was the most replicated finding, but was only reported in 4 out of 7 studies that examined this region as part of a whole brain/region of interest analysis, with 2 of these positive studies using an overlapping patient sample. The impact of episode recurrence, medications, and other clinical factors was inconsistently examined.

LIMITATIONS

The literature regarding GM changes early in BD-I is highly inconsistent, likely due to heterogeneity in participant characteristics, imaging methodology/analysis and duration of follow up.

CONCLUSIONS

Though there was some suggestion that structural ACC changes may represent a marker for neuroprogression following FEM, results were too inconsistent to draw any conclusions. Larger longitudinal studies examining cortical thickness/surface area, and the influence of relevant clinical factors, are needed to better understand neuroprogression in early BD-I.

Abnormality of subcortical volume and resting functional connectivity in adolescents with early-onset and prodromal schizophrenia

OBJECTIVE

Studies have found that there may be qualitative changes in brain structure and function in adolescents with early-onset schizophrenia (EOS) and prodromal schizophrenia (PDS). However, the abnormal brain structure and function of adolescents with EOS and PDS have received little attention, and their underlying neural mechanisms are still unknown.

METHODS

In this study, structural and resting-state functional magnetic resonance imaging (fMRI) were used to compare the subcortical volume and functional connectivity (FC) among EOS, PDS, and a control group. The Positive and Negative Symptom Scale (PNASS) questionnaire was used for clinical evaluation. Structural MRI was used to calculate cortical-based morphological volume and subcortical volume, and resting-state fMRI was used to analyze seed-based FC.

RESULTS

Structural MRI analyses showed that the gray matter volume of the hippocampus in EOS was significantly smaller than that in the control group, and the gray matter volume of the hippocampus, amygdala, and caudate nucleus in PDS was significantly smaller than that in the control group. Additionally, correlation analysis showed that the gray matter volume of the hippocampus was significantly negatively correlated with the negative symptom score of PANSS in EOS. When the hippocampus was used as the seed, fMRI analysis found that the FC between the hippocampus and the posterior cingulate gyrus and precuneus in EOS was significantly weaker than that in the control group.

CONCLUSION

Our results indicate that the brain structure and function are abnormal in EOS and PDS, with abnormalities mainly concentrated in the limbic system, including the hippocampus, amygdala, caudate nucleus, cingulate gyrus, and precuneus. These findings provide a new direction for early intervention and improvement of the prognosis of schizophrenic patients.

Grey matter abnormalities in first-episode mania: A systematic review and meta-analysis of voxel-based morphometry studies

OBJECTIVES

It has been proposed that different stages of bipolar disorder may be underpinned by distinct neurobiological substrates. However, structural neuroimaging studies in early stages of the illness are limited by small sample sizes yielding inconsistent findings. The purpose of this systematic review and meta-analysis, therefore, was to identify regional grey matter volume (GMV) changes that are consistently associated with first episode of mania (FEM).

METHODS

Following PRISMA guidelines, we conducted a systematic search of the literature to identify Voxel-Based Morphometry (VBM) studies in FEM patients compared with healthy individuals. We then conducted a voxel-wise meta-analysis using Seed-based d-Mapping technique. Finally, we performed univariate meta-regression analyses to explore the potential effects of moderator variables including age, gender, and percentage of lithium users on GMV alterations.

RESULTS

We identified 15 VBM studies and included 12 studies in the meta-analysis. Four studies found no regional differences in GM volumes while other 11 studies reported volume changes in frontal and temporal regions as well as anterior cingulate cortex (ACC), cerebellum and basal ganglia. The meta-analysis revealed a single cluster of GMV reduction in bilateral pregenual ACC in patients with FEM compared to healthy individuals (P < .001). The Egger's test showed no evidence of publication bias at peak voxel level (P = .447). Meta-regression analyses revealed no significant effects of moderators evaluated.

CONCLUSIONS

Structural brain changes are evident in the early stages of bipolar disorder. GMV reduction in bilateral pregenual ACC is the most consistent finding in VBM studies of FEM.

"First-episode psychosis: Structural covariance deficits in salience network correlate with symptoms severity"

BACKGROUND

Patterns of coordinated variations of gray matter (GM) morphology across individuals are promising indicators of disease. However, it remains unclear if they can help characterize first-episode psychosis (FEP) and symptoms' severity.

METHODS

Sixty-seven FEP and 67 matched healthy controls (HC) were assessed with structural MRI to evaluate the existence of distributed GM structural covariance patterns associated to brain areas belonging to salience network. Voxel-based morphometry (VBM) and structural covariance differences, investigated with salience network seed-based Partial Least Square, were applied to explore differences between groups. GM density associations with Raven's intelligent quotient (IQ) and Positive and Negative Syndrome Scale (PANSS) scores were investigated.

RESULTS

Univariate VBM results gave trend without significant GM differences across groups. GM and IQ correlated positively in both groups: in FEP, mostly in hippocampus, insula, and fronto-temporal structures, while in HC mostly in amygdala, thalamus and fronto-temporal regions. GM and PANSS scores correlated negatively in FEP, with widespread clusters located in limbic regions. Multivariate analysis showed strong and opposite structural GM covariance with salience network for FEP and HC. Moreover, structural covariance of the salience network in FEP correlated negatively with severity of clinical symptoms.

CONCLUSION

Our study provides evidence supporting the insular dysfunction model of psychosis. Reduced structural GM covariance of the salience network, with its association to symptom's severity, appears a promising morphometry feature for FEP detection.

A Meta-analysis of Structural and Functional Brain Abnormalities in Early-Onset Schizophrenia

Early-onset schizophrenia (EOS) patients demonstrate brain changes that are similar to severe cases of adult-onset schizophrenia. Neuroimaging research in EOS is limited due to the rarity of the disorder. The present meta-analysis aims to consolidate MRI and functional MRI findings in EOS. Seven voxel-based morphometry (VBM) and 8 functional MRI studies met the inclusion criteria, reporting whole-brain analyses of EOS vs healthy controls. Activation likelihood estimation (ALE) was conducted to identify aberrant anatomical or functional clusters across the included studies. Separate ALE analyses were performed, first for all task-dependent studies (Cognition ALE) and then only for working memory ones (WM ALE). The VBM ALE revealed no significant clusters for gray matter volume reductions in EOS. Significant hypoactivations peaking in the right anterior cingulate cortex (rACC) and the right temporoparietal junction (rTPJ) were detected in the Cognition ALE. In the WM ALE, consistent hypoactivations were found in the left precuneus (lPreC), the right inferior parietal lobule (rIPL) and the rTPJ. These hypoactivated areas show strong associations with language, memory, attention, spatial, and social cognition. The functional co-activated networks of each suprathreshold ALE cluster, identified using the BrainMap database, revealed a core co-activation network with similar topography to the salience network. Our results add support to posterior parietal, ACC and rTPJ dysfunction in EOS, areas implicated in the cognitive impairments characterizing EOS. The salience network lies at the core of these cognitive processes, co-activating with the hypoactivating regions, and thus highlighting the importance of salience dysfunction in EOS.

Neuroprogression across the Early Course of Psychosis

Psychotic disorders are severe, debilitating, and even fatal. The development of targeted and effective interventions for psychosis depends upon on clear understanding of the timing and nature of disease progression to target processes amenable to intervention. Strong evidence suggests early and ongoing neuroprogressive changes, but timing and inflection points remain unclear and likely differ across cognitive, clinical, and brain measures. Additionally, granular evidence across modalities is particularly sparse in the "bridging years" between first episode and established illness-years that may be especially critical for improving outcomes and during which interventions may be maximally effective. Our objective is the systematic, multimodal characterization of neuroprogression through the early course of illness in a cross-diagnostic sample of patients with psychosis. We aim to (1) interrogate neurocognition, structural brain measures, and network connectivity at multiple assessments over the first eight years of illness to map neuroprogressive trajectories, and (2) examine trajectories as predictors of clinical and functional outcomes. We will recruit 192 patients with psychosis and 36 healthy controls. Assessments will occur at baseline and 8- and 16-month follow ups using clinical, cognitive, and imaging measures. We will employ an accelerated longitudinal design (ALD), which permits ascertainment of data across a longer timeframe and at more frequent intervals than would be possible in a single cohort longitudinal study. Results from this study are expected to hasten identification of actionable treatment targets that are closely associated with clinical outcomes, and identify subgroups who share common neuroprogressive trajectories toward the development of individualized treatments.

Transdiagnostic neuroimaging in psychiatry: A review

Transdiagnostic approach has a long history in neuroimaging, predating its recent ascendance as a paradigm for new psychiatric nosology. Various psychiatric disorders have been compared for commonalities and differences in neuroanatomical features and activation patterns, with different aims and rationales. This review covers both structural and functional neuroimaging publications with direct comparison of different psychiatric disorders, including schizophrenia, bipolar disorder, major depressive disorder, autism spectrum disorder, obsessive-compulsive disorder, attention-deficit/hyperactivity disorder, conduct disorder, anorexia nervosa, and bulimia nervosa. Major findings are systematically presented along with specific rationales for each comparison.

Structural imaging biomarkers for bipolar disorder: Meta-analyses of whole-brain voxel-based morphometry studies

BACKGROUND

Bipolar disorder (BD) is a common and destructive psychiatric illness worldwide. Although it is known that BD is associated with morphological abnormalities of the brain, the regions implicated in BD remain unclear. Therefore, we aimed to update current knowledge on potential structural imaging biomarkers of BD.

METHODS

Studies published up to January 31, 2018, were identified by a comprehensive literature search of PubMed, EBSCO, and BrainMap voxel-based morphometry (VBM) database. Whole-brain VBM studies that examined gray matter (GM) abnormalities of group comparisons between BD and healthy controls (HC) and reported results as coordinates in a standard reference space were included. Different meta-analyses were performed by activation likelihood estimation (ALE) algorithm.

RESULTS

A total of 46 studies with 56 experiments, including 1720 subjects and 268 foci were included. Seven different meta-analyses were calculated separately across experiments reporting decreased or increased GM volume among BD, BDΙ, BD-adults, and BD-youths groups. Fifteen regions of significantly different GM volume between four groups and HC were identified. There were extensive GM deficits in the prefrontal and temporal cortex, and enlargements in the putamen, cingulate cortex, and precuneus.

CONCLUSIONS

The results revealed that the thinning of prefrontal cortex was a key region in the pathophysiology of BD. The enlargement of the cingulate cortex may be implicated in a compensatory mechanism. It underscored important differences between BD-adults and BD-youths and specific biomarkers of three subgroups.

Meta-analysis of regional white matter volume in bipolar disorder with replication in an independent sample using coordinates, T-maps, and individual MRI data

Converging evidence suggests that bipolar disorder (BD) is associated with white matter (WM) abnormalities. Meta-analyses of voxel based morphometry (VBM) data is commonly performed using published coordinates, however this method is limited since it ignores non-significant data. Obtaining statistical maps from studies (T-maps) as well as raw MRI datasets increases accuracy and allows for a comprehensive analysis of clinical variables. We obtained coordinate data (7-studies), T-Maps (12-studies, including unpublished data) and raw MRI datasets (5-studies) and analysed the 24 studies using Seed-based d Mapping (SDM). A VBM analysis was conducted to verify the results in an independent sample. The meta-analysis revealed decreased WM volume in the posterior corpus callosum extending to WM in the posterior cingulate cortex. This region was significantly reduced in volume in BD patients in the independent dataset (p=0.003) but there was no association with clinical variables. We identified a robust WM volume abnormality in BD patients that may represent a trait marker of the disease and used a novel methodology to validate the findings.