Smaller cingulate volumes in unipolar depressed patients.

BACKGROUND: The anterior cingulate cortex is a key structure in brain networks involved in mood regulation. Abnormalities in this brain region are possibly implicated in the pathophysiology of depression. This anatomical magnetic resonance imaging (MRI) study compared cingulate cortex volumes in unipolar depressed patients and age- and gender-matched healthy control subjects. METHODS: Thirty-one unmedicated DSM-IV unipolar patients (24 female, aged 39.2 +/- 11.9 years [mean +/- SD]) and 31 healthy control subjects (24 female, aged 36.7 +/- 10.7 years) were studied in a 1.5-T GE Signa magnet (General Electric Medical Systems, Milwaukee, Wisconsin). Cingulate volumes were compared by analysis of covariance with intracranial volume as the covariate. RESULTS: The unipolar patients had significantly smaller anterior and posterior cingulate volumes bilaterally compared with healthy control subjects. When patients were divided into currently depressed (n = 21) and remitted (n = 10) subgroups, currently depressed patients had significantly smaller anterior and posterior cingulate volumes bilaterally compared with healthy control subjects, whereas remitted patients had significantly smaller left anterior cingulate volumes compared with healthy individuals. CONCLUSIONS: Gray matter abnormalities in the cingulate cortex are implicated in the pathophysiology of unipolar depression. Smaller cingulate volumes in currently depressed patients support the hypothesis that cingulate cortex abnormalities are state dependent, whereas changes in left anterior cingulate might be trait related.     

Subclinical depression severity is associated with distinct patterns of functional connectivity for subregions of anterior cingulate cortex

Depression is a prevalent psychiatric condition characterized by sad mood and anhedonia. Neuroscientific research has consistently identified abnormalities in a network of brain regions in major depression, including subregions of the anterior cingulate cortex (ACC). However, few studies have investigated whether the same neural correlates of depression symptom severity are apparent in subclinical or healthy subjects. In the current study, we used resting-state fMRI to examine functional connectivity for subregions of the ACC in N = 28 participants with subclinical levels of depression. In regression analyses, we examined relationships between depression severity and functional connectivity for pregenual ACC (pgACC), anterior subgenual ACC (sgACC), and posterior sgACC seed regions. Additionally, we examined relationships between ACC subregion connectivity and trait levels of positive and negative affect. We found distinct associations between depression severity and functional connectivity of ACC subregions. Higher depression severity was associated with reduced pgACC-striatum connectivity and reduced anterior sgACC-anterior insula connectivity. Consistent with resting-state findings in major depression, higher depression severity was also related to greater anterior sgACC-posterior cingulate connectivity and greater posterior sgACC-dorsolateral prefrontal connectivity. Lastly, there were distinct correlations between connectivity for anterior versus posterior ACC subregions and positive and negative affective traits. These findings provide novel support linking subclinical depression to the same neural substrates associated with major depression. More broadly, these results contribute to an emerging literature on dimensional approaches to psychiatric illness.     

Increased anterior cingulate cortex volume in bipolar I disorder

OBJECTIVE: Functional neuroimaging studies have implicated the anterior cingulate cortex (ACC) in the pathophysiology of bipolar disorder (BD), but findings from volumetric studies have been less consistent, therefore the purpose of the present study was to further investigate the existence of volumetric abnormalities in the ACC cortex of individuals with BD. In addition to methodological inconsistencies many previous studies have been lacking robustness clinically with respect to characterizing bipolar patients and comparison subjects. Hence, the present study matched the groups closely across a number of demographic parameters. METHODS: Using magnetic resonance imaging, ACC volumes of 24 bipolar patients were compared to 24 gender-, age-, and education-matched control subjects, and these findings were further investigated in relation to both illness and treatment factors. RESULTS: A significantly larger (26%) right ACC in bipolar patients than control subjects was seen, and this difference was not associated with a history of psychosis, familiality, or lithium treatment, after controlling for potential confounds. Patients reporting fewer affective episodes did, however, have significantly larger ACC volumes than controls, suggesting ACC volumetric changes early in the course of BD. CONCLUSIONS: An increase in the size of the ACC may have important implications for the neurobiology of BD. It is suggested that attempts to control affective instability during the early stages of the illness necessitates greater ACC mediation via its role in conflict resolution and hence this is reflected in the increased size of the ACC early in the course of the illness.     

Error-related hyperactivity of the anterior cingulate cortex in obsessive-compulsive disorder.

BACKGROUND: Hyperactivity of the anterior cingulate cortex (ACC) in patients with obsessive-compulsive disorder (OCD) has been shown to increase with symptom provocation and to normalize with treatment-induced symptom reduction. Although the functional significance of anterior cingulate involvement in OCD remains unknown, electrophysiological evidence has linked this region to error-processing abnormalities in patients with OCD. In this functional magnetic resonance imaging (fMRI) study, we sought to further localize error-processing differences within the ACC of OCD patients compared with healthy subjects. METHODS: Event-related fMRI data were collected for eight OCD patients and seven healthy subjects during the performance of a simple cognitive task designed to elicit errors but not OCD symptoms. RESULTS: Both OCD patients and healthy subjects demonstrated dorsal ACC activation during error commission. The OCD patients exhibited significantly greater error-related activation of the rostral ACC than comparison subjects. Activity in this region was positively correlated with symptom severity in the patients. CONCLUSIONS: Error-processing abnormalities within the rostral anterior cingulate occur in the absence of symptom expression in patients with OCD.     

Rostral anterior cingulate cortex activity in the theta band predicts response to antidepressive medication.

During the last 10 years the knowledge about rostral anterior cingulate cortex (ACC) activity in major depression has substantially increased. Several groups have independently described a relationship between resting activity in this area and response to antidepressant treatment. We have recently confirmed a relationship between resting activity of rostral ACC activity and response in a group of 20 patients with major depression using resting theta activity. In this earlier study regions of interest (ROI) were defined in order to establish regional specificity. Differences between responders and nonresponders were only found in the ACC-ROI, but not in the posterior cingulate region. We have now reanalyzed our data using a whole brain voxelwise approach, in order not to miss any other relevant functional differences. In addition to major differences between responders and nonresponders in the rostral ACC, we have identified a nearby region in the midline orbito-frontal region.     

Anterior cingulate, gyrus rectus, and orbitofrontal abnormalities in elderly depressed patients: an MRI-based parcellation of the prefrontal cortex

OBJECTIVE: To examine structural abnormalities in subregions of the prefrontal cortex in elderly patients with depression, the authors explored differences in gray matter, white matter, and CSF volumes by applying a parcellation method based on magnetic resonance imaging (MRI). METHOD: Twenty-four elderly patients with major depression and 19 group-matched comparison subjects were studied with high-resolution MRI. Cortical surface extraction, tissue segmentation, and cortical parcellation methods were applied to obtain volume measures of gray matter, white matter, and CSF in seven prefrontal subregions: the anterior cingulate, gyrus rectus, orbitofrontal cortex, precentral gyrus, superior frontal cortex, middle frontal cortex, and inferior frontal cortex. RESULTS: Highly significant bilateral volume reductions in gray matter were observed in the anterior cingulate, the gyrus rectus, and the orbitofrontal cortex. Depressed patients also exhibited significant bilateral white matter volume reductions and significant CSF volume increases in the anterior cingulate and the gyrus rectus. Finally, the depressed group showed significant CSF volume reductions in the orbitofrontal cortex relative to the comparison subjects. None of the other regions examined revealed significant structural abnormalities. CONCLUSIONS: The prominent bilateral gray matter deficits in the anterior cingulate and the gyrus rectus as well as the orbitofrontal cortex may reflect disease-specific modifications of elderly depression. The differential pattern of abnormalities detected in the white matter and CSF compartments imply that distinct etiopathological mechanisms might underlie the structural cortical changes in these regions.     

Reduced glutamate in the anterior cingulate cortex in depression: an in vivo proton magnetic resonance spectroscopy study.

BACKGROUND: Functional imaging studies suggest a specific role of the anterior brain regions in the pathogenesis of major depression. The aim of this study was to evaluate possible neurochemical alterations in the frontomesial cortex in patients with major depressive episode using in vivo proton magnetic resonance spectroscopy ((1)H-MRS). METHODS: Single voxel (1)H-MRS was performed in 19 patients with major depressive episodes and 18 age-matched healthy controls within the anterior cingulate cortex and the parietal white matter. Absolute concentrations were estimated for N-acetyl-aspartate, choline-containing compounds, total creatine, myo-inositol, unresolved glutamate and glutamine (Glx) and glutamate alone (Glu). Voxel composition was analyzed by image segmentation into cerebrospinal fluid (CSF), grey and white matter. RESULTS: MANOVA test for Glx and Glu using age, percent CSF and percent grey matter contribution as covariates yielded a significant group effect within the anterior cingulate due to decrease of Glx in patients (-10.4%, p =.013). Considering only severely depressed patients, both Glx and Glu (-14.3%, p =.03) showed a significant decrease. There was no significant group effect for the neuronal marker NAA, creatine, choline or myo-inositol in either localization. CONCLUSIONS: This study suggests a possible role of altered glutamatergic neurotransmission within the anterior cingulate in the pathogenesis of mood disorders. The otherwise unremarkable findings of major brain metabolites confirms lack of neurodegenerative or membrane metabolic changes in major depression.     

Female specific anterior cingulate abnormality and its association with empathic disability in schizophrenia

Evidence suggests that impairments of empathy are present in schizophrenia and that such deficits lead to social dysfunction. However, the relationship between brain morphological abnormalities of the disorder and empathic disabilities has not been fully investigated. As the anterior cingulate cortex (ACC) is one of the critical structures for empathy processing, the pathology of this structure might be a major source of social dysfunction, including interpersonal miscommunication in schizophrenia. In addition, as recent studies suggest that different facets of empathic ability depend on different subdivisions of the ACC, pathology of each subdivision would affect the empathic disability of schizophrenia differentially. Structural MRI data were acquired at 3.0 T from 24 schizophrenic patients and 20 healthy participants, and the volumes of ventral and dorsal ACC were measured and compared between the groups. Subjects' empathic abilities were evaluated using a multidimensional questionnaire, the Interpersonal Reactivity Index (IRI). The relationships of structural abnormalities with empathic disabilities were investigated, by correlating ACC subdivisional volumes with each IRI subscale score. Female schizophrenic patients exhibited volume reductions in the ventral ACC bilaterally and in the left dorsal ACC compared with healthy subjects. Schizophrenic patients performed poorly on fantasy and personal distress subscales of the IRI. Furthermore, volumes of the left dorsal ACC were inversely correlated with personal distress subscale scores within female patients with schizophrenia. These results suggest that pathology of specific ACC subdivisions would have an impact on specific empathic disabilities in schizophrenia, with potential gender specificity.     

Reduced anterior cingulate cortex glutamatergic concentrations in childhood major depression

OBJECTIVE: To examine in vivo glutamatergic neurochemical alterations in the anterior cingulate cortex of children with major depressive disorder (MDD). METHOD: Single-voxel proton magnetic resonance spectroscopic (H-MRS) examinations of the anterior cingulate cortex were conducted in 13 psychotropic-na?ve children and adolescents with MDD and 13 age- and sex-matched healthy children and adolescents. Ten of the 13 MDD patient-control pairs also had a H-MRS examination of occipital cortex. RESULTS: Anterior cingulate glutamatergic (Glx) concentrations were significantly lower (19% decrease) in MDD patients versus controls (9.27 +/- 0.43 versus 11.47 +/- 0.26, respectively, p = 0.000). Reduced anterior cingulate Glx in MDD patients was associated with increased severity of functional impairment. These results remained comparably significant after controlling for age and anterior cingulate volume. Occipital cortex Glx did not differ between MDD patients and controls. CONCLUSIONS: These preliminary findings provide new evidence of localized functional neurochemical marker alterations in Glx in anterior cingulate cortex in pediatric MDD. Altered anterior cingulate Glx neurotransmission may be involved in the pathogenesis of MDD.     

Anterior cingulate dysfunction in geriatric depression

BACKGROUND: Although several brain abnormalities have been identified in geriatric depression, their relationship to the pathophysiological mechanisms leading to the development and perpetuation of this syndrome remain unclear. METHODS: This paper reviews findings on the anterior cingulate cortex (ACC) function and on the relationship of ACC abnormalities to the clinical presentation and the course of geriatric depression in order to elucidate the pathophysiological role of ACC in this disorder. RESULTS: The ACC is responsible for conflict detection and emotional evaluation of error and is connected to brain structures that regulate mood, emotional valence of thought and autonomic and visceral responses, which are functions disturbed in depression. Geriatric depression often is accompanied by abnormalities in some executive functions and has a clinical presentation consistent with ACC abnormalities. Indices of ACC dysfunction are associated with adverse outcomes of geriatric depression. CONCLUSIONS: Converging findings suggest that at least some ACC functions are abnormal in depression and these abnormalities are pathophysiologically meaningful. Indices of ACC dysfunction may be used to identify subgroups of depressed elderly patients with distinct illness course and treatment needs and serve as the theoretical background for novel treatment development.     

NMDA receptor-dependent long-term depression in the anterior cingulate cortex

Neurons and synapses in the mammalian brain exhibit plastic changes, which occur not only during development and under physiological conditions, but also under pathological conditions. One major cellular hypothesis is that activity-dependent changes in synaptic strength may contribute to the formation of memory and the expression of persistent inflammatory pain. Recently, the anterior cingulate cortex (ACC) has been proposed to play an important role for learning, memory and chronic pain. Long-term potentiation (LTP) and long-term depression (LTD) are well-studied phenomena which may be related to learning and memory. NMDA receptors are the most important trigger for LTP and LTD of synaptic strength. Here, we review recent studies and present new experimental data on the roles of NMDA receptors during synaptic depression in the ACC. Furthermore, we consider the physiological and pathological significance of LTD in the ACC.     

Functional impairment‐based segmentation of anterior cingulate cortex in depression and its relationship with treatment effects

In major depressive disorder (MDD), the anterior cingulate cortex (ACC) is widely related to depression impairment and antidepressant treatment response. The multiplicity of ACC subdivisions calls for a fine‐grained investigation of their functional impairment and recovery profiles. We recorded resting state fMRI signals from 59 MDD patients twice before and after 12‐week antidepressant treatment, as well as 59 healthy controls (HCs). With functional connectivity (FC) between each ACC voxel and four regions of interests (bilateral dorsolateral prefrontal cortex [DLPFC] and amygdalae), subdivisions with variable impairment were identified based on groups'' dissimilarity values between MDD patients before treatment and HC. The ACC was subdivided into three impairment subdivisions named as MedialACC, DistalACC, and LateralACC according to their dominant locations. Furthermore, the impairment pattern and the recovery pattern were measured based on group statistical analyses. DistalACC impaired more on its FC with left DLPFC, whereas LateralACC showed more serious impairment on its FC with bilateral amygdalae. After treatment, FCs between DistalACC and left DLPFC, and between LateralACC and right amygdala were normalized while impaired FC between LateralACC and left amygdala kept dysfunctional. Subsequently, FC between DistalACC and left DLPFC might contribute to clinical outcome prediction. Our approach could provide an insight into how the ACC was impaired in depression and partly restored after antidepressant treatment, from the perspective of the interaction between ACC subregions and critical frontal and subcortical regions.     

Anterior cingulate volumes associated with trait impulsivity in individuals with bipolar disorder

Objective:  Impulsivity is associated with the clinical outcome and likelihood of risky behaviors among bipolar disorder (BD) patients. Our previous study showed an inverse relationship between impulsivity and orbitofrontal cortex (OFC) volume in healthy subjects. We hypothesized that BD patients would show an inverse relationship between impulsivity and volumes of the OFC, anterior cingulate cortex (ACC), medial prefrontal cortex, and amygdala, which have been implicated in the pathophysiology of BD.
Methods:  Sixty-three BD patients were studied (mean ± SD age = 38.2 ± 11.5 years; 79% female). The Barratt Impulsiveness Scale (BIS), version 11A, was used to assess trait impulsivity. Images were processed using SPM2 and an optimized voxel-based morphometry protocol. We examined the correlations between BIS scores and the gray matter (GM) and white matter (WM) volumes of the prespecified regions.
Results:  Left rostral ACC GM volume was inversely correlated with the BIS total score ( t  =   3.95, p_corrected = 0.003) and the BIS motor score ( t  =   5.22, p_corrected < 0.001). In contrast to our hypothesis, OFC volumes were not significantly associated with impulsivity in BD. No WM volume of any structure was significantly correlated with impulsivity. No statistical association between any clinical variable and the rostral ACC GM volumes reached significance.
Conclusions:  Based on our previous findings and the current results, impulsivity may have a different neural representation in BD and healthy subjects, and the ACC may be involved in the pathophysiology of abnormal impulsivity regulation in BD patients.     

Reduced volume of orbitofrontal cortex in major depression.

BACKGROUND: Functional neuroimaging studies have implicated dysfunction of orbitofrontal cortex in the symptoms of depression, and a recent postmortem study of depressed patients found reduced density of neurons and glia in this area. The purpose of this study was to measure volume of orbitofrontal cortex and other frontal cortical subregions in patients with major depression. METHODS: Magnetic resonance imaging was used to measure volume of the orbitofrontal cortex and other frontal cortical regions in patients with major depression in remission (n = 15) and comparison subjects (n = 20). RESULTS: Patients with depression had a statistically significant 32% smaller medial orbitofrontal (gyrus rectus) cortical volume, without smaller volumes of other frontal regions including anterior cingulate Brodmann's area 24 (subgenual gyrus), anterior cingulate Brodmann's area 32, subcallosal gyrus (Brodmann's area 25), or whole brain volume. The findings were significant after statistically controlling for brain size. CONCLUSIONS: These findings are consistent with smaller orbitofrontal cortical volume in depression.     

Anterior cingulate subregion volumes and executive function in bipolar disorder

OBJECTIVE: Although research findings suggest a relationship between the function of anterior cingulate cortex (ACC) and both cognitive ability and the pathophysiology of bipolar disorder (BPD), few studies have examined cognitive correlates of specific ACC subregion volumes in BPD. Therefore, the primary aim of this study was to examine the relationship between magnetic resonance imaging (MRI)-derived gray and white matter volumes of ACC subregions (caudal, rostral, and subgenual) and performance on tests of executive function in 27 patients with BPD and 22 healthy subjects. METHODS: 1.5T MRI and neuropsychological assessment were conducted with all participants. RESULTS: MANCOVA revealed statistically significant group differences in performance on executive function measures. However, no group differences were observed in any of the ACC white matter or gray matter regions of interest. Multiple regression analyses revealed that rostral and subgenual gray matter each interacted significantly with group in predicting performance on the Wisconsin Card Sorting Test. In addition, a significant interaction was observed between group and both rostral gray and white matter in predicting performance on the Trail Making Test. CONCLUSIONS: The results of this preliminary study support the extant literature that suggests that patients with BPD perform more poorly than healthy subjects on tests of executive function. Furthermore, the relationship between ACC subregion volumes and cognitive test performance was found to differ between patients with BPD and healthy subjects, despite comparable ACC volumes in the two groups.     

Surface-based morphometry of the anterior cingulate cortex in first episode schizophrenia

The anterior cingulate cortex (ACC) appears to be critically involved in the pathophysiology of schizophrenia, but past attempts at characterizing pathological changes in the region using magnetic resonance imaging have been restricted by a limited appreciation of its functional and anatomical diversity and a reliance on relatively coarse metrics (e.g., volume) to index anatomical change. In this study, we applied a novel, surface-based protocol to T1-weighted scans acquired from 40 first episode schizophrenia patients and 40 healthy controls individually matched for age, sex, and morphology of the paracingulate sulcus, a major anatomical variation that has been shown to affect morphometric estimates in the region. The surface-based approach enabled calculation of regional grey matter volume, surface area and curvature, cortical thickness, and depth of the cingulate sulcus, with sub-millimeter precision. Relative to controls, schizophrenia patients displayed a bilateral reduction in thickness of paralimbic regions of the ACC, along with a concomitant increase in surface area of both the limbic and paralimbic ACC. No differences were identified for regional grey matter volume, surface curvature, or CS depth. These findings illustrate the advantages of moving beyond traditional volume-based approaches when investigating cortical morphometry, and indicate that the early stages of schizophrenia are associated with a specific pattern of ACC abnormalities that cannot be attributed to variations in sulcal and gyral morphology.     

Decreased dopamine D2 receptor binding in the anterior cingulate cortex in schizophrenia.

BACKGROUND: The clinical efficacy of dopamine D2 receptor antagonism on the psychotic symptoms of schizophrenia has been widely demonstrated. However, most in vivo imaging studies have not been able to detect significant changes in striatal D2 receptors in schizophrenia. On the other hand, a number of studies have reported abnormalities in the cerebral cortex of schizophrenia. The aim of this study was to examine the extrastriatal D2 receptors of patients with schizophrenia. METHODS: Eleven drug-naive male patients with schizophrenia were examined with positron emission tomography using carbon 11-labeled FLB 457. Symptoms were assessed using the Brief Psychiatric Rating Scale. Eighteen healthy controls were used for comparison. Region-of-interest analysis was performed using the reference tissue method, and binding potential (BP) was used for the index of dopamine D2 receptor binding. RESULTS: The BP value was significantly lower, by about 12.5%, in the anterior cingulate cortex in drug-naive patients with schizophrenia than in healthy controls. A significant negative correlation was observed between BP in the anterior cingulate cortex and the positive symptom score on Brief Psychiatric Rating Scale. CONCLUSIONS: The lower BP values indicate fewer D2 receptors in the anterior cingulate cortex in patients with schizophrenia. Alterations in D2 receptor function in the extrastriatal region may underlie the positive symptoms of schizophrenia.     

Anterior cingulate cortex volume reduction in patients with panic disorder

Aim:  Recent neuroimaging studies have suggested that the anterior cingulate cortex (ACC) has an important role in the pathology of panic disorder. Despite numerous functional neuroimaging studies that have elucidated the strong relationship between functional abnormalities of the ACC and panic disorder and its symptoms and response to emotional tasks associated with panic disorder, there has been no study showing volumetric changes of the ACC or its subregions.
Methods:  To clarify the structural abnormalities of ACC and its subregions, the combination of region of interest (ROI) and optimized voxel-based morphometry (VBM) methods were performed on 26 patients with panic disorder, and 26 age and sex-matched healthy subjects. In the ROI study, ACC was divided into four subregions: dorsal, rostral, subcallosal and subgenual ACC.
Results:  The results of the manually traced ROI volume comparison showed significant volume reduction in the right dorsal ACC. VBM also showed a volume reduction in the right dorsal as well as a part of the rostral ACC as a compound mass.
Conclusions:  Both manual ROI tracing and optimized VBM suggest a subregion-specific pattern of ACC volume deficit in panic disorder. In addition to functional abnormalities, these results suggest that structural abnormalities of the ACC contribute to the pathophysiology of panic disorder.     

Reduced gray matter volume of dorsal cingulate cortex in patients with obsessive-compulsive disorder: a voxel-based morphometric study

Aims: Previous morphometric studies using magnetic resonance imaging (MRI) have revealed structural brain abnormalities in obsessive–compulsive disorder (OCD). The aim of the present study was to investigate the alterations in brain structure of patients with OCD using a voxel‐based morphometry (VBM) method. Methods: Sixteen patients with OCD free of comorbid major depression, and 32 sex‐ and age‐matched healthy subjects underwent MRI using a 1.5‐T MR scanner. OCD severity was assessed with the Yale–Brown Obsessive–Compulsive Scale (mean ± SD: 22 ± 7.6; range: 7–32). MR images were spatially normalized and segmented using the VBM5 package ( http://dbm.neuro.uni‐jena.de/vbm/ ). Statistical analysis was performed using statistical parametric mapping software. Results: Significant reductions in regional gray matter volume were detected in the left caudal anterior cingulate cortex and right dorsal posterior cingulate cortex in the patients with OCD as compared to healthy controls (uncorrected, P < 0.001). No significant differences in white matter volumes were observed in any brain regions of the patients. No significant correlation between Yale–Brown Obsessive–Compulsive Scale score and regional gray matter or white matter volume was observed. Conclusions: Regional gray matter alteration in the dorsal cingulate cortex, which is suggested to play a role in non‐emotional cognitive processes, may be related to the pathophysiology in OCD.     

Microvascular changes in late‐life schizophrenia and mood disorders: stereological assessment of capillary diameters in anterior cingulate cortex

L. Sinka, E. Kovari, M. Santos, F. R. Herrmann, G. Gold, P. R. Hof, C. Bouras and P. Giannakopoulos (2012) Neuropathology and Applied Neurobiology 38, 696–709 Microvascular changes in late‐life schizophrenia and mood disorders: stereological assessment of capillary diameters in anterior cingulate cortex Aims: Previous neuroimaging reports described morphological and functional abnormalities in anterior cingulate cortex (ACC) in schizophrenia and mood disorders. In earlier neuropathological studies, microvascular changes that could affect brain perfusion in these disorders have rarely been studied. Here, we analysed morphological parameters of capillaries in this area in elderly cases affected by these psychiatric disorders. Methods: We analysed microvessel diameters in the dorsal and subgenual parts of the ACC in eight patients with schizophrenia, 10 patients with sporadic bipolar disorder, eight patients with sporadic major depression, and seven age‐ and gender‐matched control cases on sections stained with modified Gallyas silver impregnation using a stereological counting approach. All individuals were drug‐naïve or had received psychotropic medication for less than 6 months, and had no history of substance abuse. Statistical analysis included Kruskal–Wallis group comparisons with Bonferroni correction as well as multivariate regression models. Results: Mean capillary diameter was significantly decreased in the dorsal and subgenual parts of areas 24 in bipolar and unipolar depression cases, both in layers III and V, whereas schizophrenia patients were comparable with controls. These differences persisted when controlling for age, local neuronal densities, and cortical thickness. In addition, cortical thickness was significantly smaller in both layers in schizophrenia patients. Conclusions: Our findings indicate that capillary diameters in bipolar and unipolar depression but not in schizophrenia are reduced in ACC. The significance of these findings is discussed in the light of the cytoarchitecture, brain metabolism and perfusion changes observed in ACC in mood disorders.