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1.
Schizophr Res ; 261: 6-14, 2023 11.
Article in English | MEDLINE | ID: mdl-37678145

ABSTRACT

BACKGROUND: Excessive C4A-gene expression may result in increased microglia-mediated synaptic pruning. As C4A overexpression is observed in schizophrenia spectrum disorders (SSD), this mechanism may account for the altered brain morphology (i.e. reduced volume and cortical thickness) and cognitive symptoms that characterize SSD. Therefore, this study investigates the association of C4A serum protein levels with brain morphology and cognition, and in particular whether this association differs between recent-onset SSD (n = 69) and HC (n = 40). METHODS: Serum C4A protein levels were compared between groups. Main outcomes included total gray matter volume, mean cortical thickness and cognitive performance. Regression analysis on these outcomes included C4A level, group (SSD vs. HC), and C4A*Group interactions. All statistical tests were corrected for age, sex, BMI, and antipsychotic medication dose. Follow-up analyses were performed on separate brain regions and scores on cognitive sub-tasks. RESULTS: The group difference in C4A levels was not statistically significant (p = 0.86). The main outcomes did not show a significant interaction effect (p > 0.13) or a C4A main effect (p > 0.27). Follow-up analyses revealed significant interaction effects for the left medial orbitofrontal and left frontal pole volumes (p < 0.001): C4A was negatively related to these volumes in SSD, but positively in HC. CONCLUSION: This study demonstrated that C4A was negatively related to - specifically - frontal brain volumes in SSD, but this relation was inverse for HC. The results support the hypothesis of complement-mediated brain volume reduction in SSD. The results also suggest that C4A has a differential association with brain morphology in SSD compared to HC.


Subject(s)
Schizophrenia , Humans , Schizophrenia/diagnostic imaging , Schizophrenia/complications , Complement C4a , Brain/metabolism , Gray Matter/metabolism , Cognition , Magnetic Resonance Imaging
2.
Neuroimage Clin ; 37: 103292, 2023.
Article in English | MEDLINE | ID: mdl-36565574

ABSTRACT

BACKGROUND: Physical exercise in cancer patients is a promising intervention to improve cognition and increase brain volume, including hippocampal volume. We investigated whether a 6-month exercise intervention primarily impacts total hippocampal volume and additionally hippocampal subfield volumes, cortical thickness and grey matter volume in previously physically inactive breast cancer patients. Furthermore, we evaluated associations with verbal memory. METHODS: Chemotherapy-exposed breast cancer patients (stage I-III, 2-4 years post diagnosis) with cognitive problems were included and randomized in an exercise intervention (n = 70, age = 52.5 ± 9.0 years) or control group (n = 72, age = 53.2 ± 8.6 years). The intervention consisted of 2x1 hours/week of supervised aerobic and strength training and 2x1 hours/week Nordic or power walking. At baseline and at 6-month follow-up, volumetric brain measures were derived from 3D T1-weighted 3T magnetic resonance imaging scans, including hippocampal (subfield) volume (FreeSurfer), cortical thickness (CAT12), and grey matter volume (voxel-based morphometry CAT12). Physical fitness was measured with a cardiopulmonary exercise test. Memory functioning was measured with the Hopkins Verbal Learning Test-Revised (HVLT-R total recall) and Wordlist Learning of an online cognitive test battery, the Amsterdam Cognition Scan (ACS Wordlist Learning). An explorative analysis was conducted in highly fatigued patients (score of ≥ 39 on the symptom scale 'fatigue' of the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire), as previous research in this dataset has shown that the intervention improved cognition only in these patients. RESULTS: Multiple regression analyses and voxel-based morphometry revealed no significant intervention effects on brain volume, although at baseline increased physical fitness was significantly related to larger brain volume (e.g., total hippocampal volume: R = 0.32, B = 21.7 mm3, 95 % CI = 3.0 - 40.4). Subgroup analyses showed an intervention effect in highly fatigued patients. Unexpectedly, these patients had significant reductions in hippocampal volume, compared to the control group (e.g., total hippocampal volume: B = -52.3 mm3, 95 % CI = -100.3 - -4.4)), which was related to improved memory functioning (HVLT-R total recall: B = -0.022, 95 % CI = -0.039 - -0.005; ACS Wordlist Learning: B = -0.039, 95 % CI = -0.062 - -0.015). CONCLUSIONS: No exercise intervention effects were found on hippocampal volume, hippocampal subfield volumes, cortical thickness or grey matter volume for the entire intervention group. Contrary to what we expected, in highly fatigued patients a reduction in hippocampal volume was found after the intervention, which was related to improved memory functioning. These results suggest that physical fitness may benefit cognition in specific groups and stress the importance of further research into the biological basis of this finding.


Subject(s)
Breast Neoplasms , Humans , Adult , Middle Aged , Female , Breast Neoplasms/diagnostic imaging , Breast Neoplasms/pathology , Gray Matter/diagnostic imaging , Quality of Life , Exercise , Hippocampus/diagnostic imaging , Hippocampus/pathology , Magnetic Resonance Imaging/methods
3.
Schizophr Res ; 241: 228-237, 2022 03.
Article in English | MEDLINE | ID: mdl-35176721

ABSTRACT

INTRODUCTION: Cognitive deficits are present in some, but not all patients with schizophrenia-spectrum disorders (SSD). We and others have demonstrated three cognitive clusters: cognitively intact patients, patients with deficits in a few domains and those with global cognitive deficits. This study aimed to identify cognitive subtypes of early-phase SSD with matched controls as a reference group, and evaluated cognitive subgroups regarding clinical and brain volumetric measures. METHODS: Eighty-six early-phase SSD patients were included. Hierarchical cluster analysis was conducted using global performance on the Brief Assessment of Cognition in Schizophrenia (BACS). Cognitive subgroups were subsequently related to clinical and brain volumetric measures (cortical, subcortical and cortical thickness) using ANCOVA. RESULTS: Three distinct cognitive clusters emerged: relative to controls we found one cluster of patients with preserved cognition (n = 25), one moderately impaired cluster (n = 38) and one severely impaired cluster (n = 23). Cognitive subgroups were characterized by differences in volume of the left postcentral gyrus, left middle caudal frontal gyrus and left insula, while differences in cortical thickness were predominantly found in fronto-parietal regions. No differences were demonstrated in subcortical brain volume. DISCUSSION: Current results replicate the existence of three distinct cognitive subgroups including one relatively large group with preserved cognitive function. Cognitive subgroups were characterized by differences in cortical regional brain volume and cortical thickness, suggesting associations with cortical, but not subcortical development and cognitive functioning such as attention, executive functions and speed of processing.


Subject(s)
Cognition Disorders , Cognitive Dysfunction , Schizophrenia , Brain/diagnostic imaging , Cognition , Cognition Disorders/complications , Cognition Disorders/etiology , Cognitive Dysfunction/diagnostic imaging , Cognitive Dysfunction/etiology , Humans , Magnetic Resonance Imaging , Schizophrenia/complications , Schizophrenia/diagnostic imaging
4.
NPJ Schizophr ; 6(1): 10, 2020 Apr 20.
Article in English | MEDLINE | ID: mdl-32313047

ABSTRACT

Language deviations are a core symptom of schizophrenia. With the advances in computational linguistics, language can be easily assessed in exact and reproducible measures. This study investigated how language characteristics relate to schizophrenia diagnosis, symptom, severity and integrity of the white matter language tracts in patients with schizophrenia and healthy controls. Spontaneous speech was recorded and diffusion tensor imaging was performed in 26 schizophrenia patients and 22 controls. We were able to classify both groups with a sensitivity of 89% and a specificity of 82%, based on mean length of utterance and clauses per utterance. Language disturbances were associated with negative symptom severity. Computational language measures predicted language tract integrity in patients (adjusted R2 = 0.467) and controls (adjusted R2 = 0.483). Quantitative language analyses have both clinical and biological validity, offer a simple, helpful marker of both severity and underlying pathology, and provide a promising tool for schizophrenia research and clinical practice.

5.
Neurosci Biobehav Rev ; 36(1): 198-205, 2012 Jan.
Article in English | MEDLINE | ID: mdl-21672551

ABSTRACT

For major depressive disorder (MDD), magnetic resonance spectroscopy ((1)H-MRS) studies of glutamate, glutamine and Glx (the composite measure of mainly glutamate and glutamine) have yielded inconclusive or seemingly inconsistent results. We therefore systematically reviewed whether in vivo concentrations of glutamate, glutamine and Glx measured with (1)H-MRS differ between MDD patients and controls. Meta-analysis including meta-regression, sensitivity, statistical heterogeneity, and publication bias analyses were conducted. Glutamate and Glx concentrations were found to be lower in the anterior cingulate cortex (ACC) in patients compared to controls (standardized mean difference (SMD) for glutamate with 95% CIs: -0.86, -1.55 to -0.17; and for Glx: -1.15, -1.86 to -0.44). In addition, Glx was decreased in all brain regions together in current episode patients (SMD: -0.62, -1.17 to -0.07). We conclude that in MDD, glutamate and possibly glutamine are downregulated primarily in the ACC and during depressive states. These results fit the central role of the ACC in depressive symptomatology and suggest that in MDD changes in glutamatergic neurotransmission are state-dependent.


Subject(s)
Brain , Depressive Disorder, Major , Down-Regulation/physiology , Electrons , Glutamic Acid/metabolism , Magnetic Resonance Spectroscopy , Brain/diagnostic imaging , Brain/metabolism , Brain/pathology , Depressive Disorder, Major/diagnostic imaging , Depressive Disorder, Major/metabolism , Depressive Disorder, Major/pathology , Humans , Models, Biological , Radionuclide Imaging
6.
Schizophr Res ; 130(1-3): 68-77, 2011 Aug.
Article in English | MEDLINE | ID: mdl-21641775

ABSTRACT

Auditory verbal hallucinations (AVH) is a common and stressful symptom of schizophrenia. Disrupted connectivity between frontal and temporo-parietal language areas, giving rise to the misattribution of inner speech, is speculated to underlie this phenomenon. Disrupted connectivity should be reflected in the microstructure of the arcuate fasciculi (AF); the main connection between frontal and temporo-parietal language areas. In this study we compared microstructural properties of the AF and three other fiber tracts (cortical spinal tract, cingulum and uncinate fasciculus), between 44 schizophrenia patients with chronic severe hallucinations and 42 control subjects using diffusion tensor imaging (DTI) and magnetic transfer imaging (MTI). The DTI scans were used to compute fractional anisotropy (FA) and to reconstruct the fiber bundles of interest, while the MTI scans were used to compute magnetic transfer ratio (MTR) values. The patient group showed a general decrease in FA for all bundles. In the arcuate fasciculus this decreased FA was coupled to a significant increase in MTR values. A correlation was found between mean MTR values in both arcuate fasciculi and the severity of positive symptoms. The combination of decreased FA and increased MTR values observed in the arcuate fasciculi in patients suggests increased free water concentrations, probably caused by degraded integrity of the axons or the supportive glia cells. This suggests that disintegrated fiber integrity in the connection between frontal and temporo-parietal language areas in the schizophrenia patients is associated with their liability for auditory verbal hallucinations.


Subject(s)
Brain Mapping , Hallucinations/etiology , Neural Pathways/pathology , Schizophrenia/complications , Schizophrenia/pathology , Adolescent , Adult , Analysis of Variance , Diffusion Tensor Imaging , Female , Frontal Lobe/pathology , Humans , Image Processing, Computer-Assisted , Male , Middle Aged , Psychiatric Status Rating Scales , Temporal Lobe/pathology , Young Adult
7.
Neuroimage ; 21(4): 1805-17, 2004 Apr.
Article in English | MEDLINE | ID: mdl-15050601

ABSTRACT

Transcranial Magnetic Stimulation (TMS) delivers short magnetic pulses that penetrate the skull unattenuated, disrupting neural processing in a noninvasive, reversible way. To disrupt specific neural processes, coil placement over the proper site is critical. Therefore, a neural navigator (NeNa) was developed. NeNa is a frameless stereotactic device using structural and functional magnetic resonance imaging (fMRI) data to guide TMS coil placement. To coregister the participant's head to his MRI, 3D cursors are moved to anatomical landmarks on a skin rendering of the participants MRI on a screen, and measured at the head with a position measurement device. A method is proposed to calculate a rigid body transformation that can coregister both sets of coordinates under realistic noise conditions. After coregistration, NeNa visualizes in real time where the device is located with respect to the head, brain structures, and activated areas, enabling precise placement of the TMS coil over a predefined target region. NeNa was validated by stimulating 5 x 5 positions around the 'motor hotspot' (thumb movement area), which was marked on the scalp guided by individual fMRI data, while recording motor-evoked potentials (MEPs) from the abductor pollicis brevis (APB). The distance between the center of gravity (CoG) of MEP responses and the location marked on the scalp overlying maximum fMRI activation was on average less then 5 mm. The present results demonstrate that NeNa is a reliable method for image-guided TMS coil placement.


Subject(s)
Brain/physiology , Image Processing, Computer-Assisted/instrumentation , Imaging, Three-Dimensional/instrumentation , Magnetic Resonance Imaging/instrumentation , Neuronavigation/instrumentation , Stereotaxic Techniques/instrumentation , Transcranial Magnetic Stimulation/therapeutic use , Algorithms , Brain Mapping , Electromyography/instrumentation , Equipment Design , Evoked Potentials, Motor/physiology , Humans , Motor Activity/physiology , Motor Cortex/physiology , Reproducibility of Results , Software , Synaptic Transmission/physiology , Thumb/innervation , Transcranial Magnetic Stimulation/instrumentation
8.
Schizophr Res ; 60(2-3): 183-90, 2003 Apr 01.
Article in English | MEDLINE | ID: mdl-12591582

ABSTRACT

Gender differences in schizophrenia are among the most consistently reported findings in schizophrenia research. However, the biological substrate underlying these gender differences is still largely unknown. Differences in language lateralization between men and women may underlie some gender differences in schizophrenia. In previous functional imaging studies, language lateralization was found to be decreased in male schizophrenia patients as compared to healthy males, which was due to enhanced language activation of the right hemisphere as compared to the healthy males. It could be hypothesized that decreased language lateralization in schizophrenia is gender specific, i.e. decreased lateralization in male patients and normal lateralization in female patients. To test this hypothesis, language activation was measured in 12 right-handed female patients with schizophrenia and 12 healthy females, and compared to findings in 12 male patients and 12 male controls of an earlier study. Language lateralization was significantly lower in the female patients (0.44) as compared to the female controls (0.75), which was due to increased activation of the right-sided language areas (patients: 19 voxels; controls: 8 voxels), while left hemisphere activation was similar in patients and controls. When these data are compared to the male patients and controls, both patient groups had lower lateralization than their healthy counterparts, but there was no difference between male and female patients. In both sexes, decreased lateralization resulted from increased right hemispheric language activation, which suggests a failure to inhibit nondominant language areas in schizophrenia. These findings indicate that lower language lateralization in women is not likely to underlie gender differences in schizophrenia.


Subject(s)
Cerebral Cortex/physiopathology , Dominance, Cerebral , Language , Schizophrenia, Paranoid/physiopathology , Adult , Analysis of Variance , Brain Mapping , Case-Control Studies , Female , Humans , Magnetic Resonance Imaging , Sex Factors
9.
Brain ; 125(Pt 12): 2710-8, 2002 Dec.
Article in English | MEDLINE | ID: mdl-12429598

ABSTRACT

An unexpectedly high percentage of monozygotic twin pairs is discordant for handedness. Some of these twins show mirror-imaging of several ectodermally derived features. Both features of discordant left-right asymmetry may be caused by relatively late monozygotic twinning, when the original embryo has already lost its bilateral symmetry. Language lateralization is related to handedness and may therefore also be altered during the development of embryological asymmetry in some monozygotic twins. Language lateralization was measured with functional MRI in 12 monozygotic twin pairs who were concordant for handedness and in 13 monozygotic twin pairs discordant for handedness. Lateralization indices were calculated from individual language activation patterns. Correlations were calculated to test intra-pair resemblance for language lateralization. The intra-pair correlation for language lateralization was significant in the handedness-concordant group, but not in the handedness-discordant group. In the handedness-discordant group, five twin pairs were also discordant for cerebral dominance; the other twin pairs of discordant handedness exhibited remarkable similarity in language lateralization. The high intra-pair correlation for language lateralization in the handedness-concordant twins suggests a genetic basis for language lateralization. However, in monozygotic twin pairs of discordant handedness, discordance for language dominance occurs in a significant number of twins. Discordant language dominance may be caused by a relatively late time of splitting of the original embryo, which disrupts the normal development of left-right asymmetry.


Subject(s)
Functional Laterality/genetics , Language , Twins, Monozygotic/genetics , Female , Humans , Magnetic Resonance Imaging/methods , Male
10.
Br J Psychiatry Suppl ; 43: s66-72, 2002 Sep.
Article in English | MEDLINE | ID: mdl-12271803

ABSTRACT

BACKGROUND: Although brain volume changes are found in schizophrenia, only a limited number of structural magnetic resonance imaging studies have exclusively examined antipsychotic-naïve patients. AIMS: To comprehensively investigate multiple brain structures in a single sample of patients who were antipsychotic-naïve. METHOD: Twenty antipsychotic-naïve patients with first-episode schizophrenia and 20 healthy comparison subjects were included. Intracranial, total brain, frontal lobe, grey and white matter, cerebellar, hippocampal, parahippocampal, thalamic, caudate nucleus and lateral and third ventricular volumes were measured. Repeated-measures analyses of (co)variance were conducted with intracranial volume as covariate. RESULTS: Third ventricle volume enlargement was found in patients compared with the healthy subjects. No differences were found in other brain regions. CONCLUSIONS: These findings suggest that some brain abnormalities are present in the early stages of schizophrenia. Moreover, it suggests that brain abnormalities reported in patients with chronic schizophrenia develop in a later stage of the disease and/or are medication induced.


Subject(s)
Brain/pathology , Schizophrenia/pathology , Adolescent , Adult , Brain Diseases/diagnosis , Caudate Nucleus/pathology , Cerebellum/pathology , Cerebral Ventricles/pathology , Female , Frontal Lobe/pathology , Hippocampus/pathology , Humans , Magnetic Resonance Imaging/methods , Male , Thalamus/pathology
11.
Arch Gen Psychiatry ; 58(12): 1118-25, 2001 Dec.
Article in English | MEDLINE | ID: mdl-11735840

ABSTRACT

BACKGROUND: The view that schizophrenia is a brain disease particularly involving decrements in gray matter is supported by findings from many imaging studies. However, it is unknown whether the (progressive) loss of tissue affects the brain globally or whether tissue loss is more prominent in some areas than in others. METHODS: Magnetic resonance whole brain images were acquired from 159 patients with schizophrenia or a schizophreniform disorder and 158 healthy subjects across a 55-year age span. Gray matter density maps were made and analyzed using voxel-based morphometry. RESULTS: Compared with healthy subjects, decreases in gray matter density were found in the left amygdala; left hippocampus; right supramarginal gyrus; thalamus; (orbito) frontal, (superior) temporal, occipitotemporal, precuneate, posterior cingulate, and insular cortices bilaterally in patients with schizophrenia or schizophreniform disorder. Compared with healthy subjects, increases in gray matter density were exclusively found in the right caudate and globus pallidus in patients with schizophrenia or schizophreniform disorder. A group-by-age interaction for density was found in the left amygdala, owing to a negative regression slope of gray matter density on age in the left amygdala in patients compared with healthy subjects. CONCLUSIONS: Gray matter density is decreased in distinct focal areas in the brains of patients with schizophrenia or schizophreniform disorder. The decreased density in the left amygdala is more pronounced in older patients with schizophrenia.


Subject(s)
Brain/pathology , Image Processing, Computer-Assisted , Magnetic Resonance Imaging , Psychotic Disorders/diagnosis , Schizophrenia/diagnosis , Adolescent , Adult , Aged , Brain Mapping , Dominance, Cerebral/physiology , Echo-Planar Imaging , Female , Humans , Male , Middle Aged , Reference Values
12.
Med Staff Couns ; 6(1): 49-59, 1992.
Article in English | MEDLINE | ID: mdl-10115451

ABSTRACT

The last few years have brought rapid developments in the law regarding advance directives--both statutory and case law. This article provides an overview of these changes, including the recent amendments to the Medicare and Medicaid laws requiring hospitals and other institutional health care providers to inform adult patients and educate staff and the community about the availability and use of advance directives and the New York and Massachusetts statutes providing for the appointment of health care agents by proxy.


Subject(s)
Advance Directives/legislation & jurisprudence , Health Facilities/legislation & jurisprudence , Legal Guardians/legislation & jurisprudence , Euthanasia, Passive/legislation & jurisprudence , Liability, Legal , Massachusetts , Medicaid/legislation & jurisprudence , Medicare/legislation & jurisprudence , New York , Policy Making , United States
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