Hippocampal subdivision and amygdalar volumes in patients in an at-risk mental state for schizophrenia

Background

Accumulating evidence from postmortem and magnetic resonance imaging (MRI) studies suggests that abnormalities of medial temporal lobe structures are critically involved in the pathogenesis of schizophrenia. It is still unclear, however, whether certain abnormalities are already present in individuals at ultra high-risk (UHR) for transition into psychosis. Recent studies involving patients at UHR showed contradictory results for hippocampal volume, and only 1 study reported that amygdalar volume was unchanged between healthy patients and those at UHR. Furthermore, no subregions of the hippocampus have been investigated in people at UHR.

Methods

We recruited 29 UHR patients, 23 first-episode patients and 29 age-and sex-matched healthy controls. We measured hippocampal and amygdalar volumes from MRI scans by use of BRAINS2 to manually trace the regions of interest. The hippocampi were divided in 2 regions: head and corpus/tail.

Results

Patients at UHR had significantly smaller volumes of the hippocampus corpus and tail bilaterally, but not of the head, compared with healthy controls. Group differences for the right hippocampus corpus and tail volume remained significant after we controlled for whole brain volume and other covariates. We found that UHR patients who later developed psychosis had smaller right hippocampus corpus and tail volumes than did those who did not develop psychosis. First-episode patients had significantly smaller left amygdalar volumes than did healthy individuals or those at UHR.

Limitations

Our study had a small sample size, and we were unable to control for the effects of medication.

Conclusion

Our findings suggest that parts of the hippocampal–amygdalar complex are involved in the pathogenesis of schizophrenia. Reduction of hippocampus corpus and tail volumes may be indicative of the prodromal phase of schizophrenia and represent risk factors for transition into psychosis. Further investigations are needed to determine whether structural changes of the left amygdala play a role during transition from the prodromal phase to the first manifest episode of schizophrenia.     

Pituitary Volumes Are Reduced in Patients with Somatization Disorder

Objective

Despite of the suggested physiological relationship between somatoform disorder and disturbances in HPA axis function no volumetric study of pituitary volumes in somatization disorder has been carried out. Therefore, we aimed to use structural MRI to evaluate the pituitary volumes of the patients with somatization disorder.

Methods

Eighteen female patients with somatization disorder according to DSM-IV and same number of healthy controls were included into the study. All subjects were scanned using a 1.5-T General Electric (GE; Milwaukee, USA) scanner. Pituitary volume measurements were determined by using manuallly tracings according to standard antomical atlases.

Results

It was found significantly smaller pituitary volumes of the whole group of somatization patients compared to healthy (t=-3.604, p=0.001). ANCOVA predicting pituitary volumes demonstrated a significant main effect of diagnostic group (F=13.530, p<0.001) but TBV (F=1.924, p>0.05) or age (F=1.159, p>0.05). It was determined that there was no significant correlation between smaller pituitary volumes and the duration of illness (r=0.16, p>0.05) in the patient group.

Conclusion

In conclusion, we suggest that the patients with somatization disorder might have significantly smaller pituitary volumes compared to healthy control subjects.     

Progressive structural brain changes during development of psychosis

Background:

Ultra-high risk (UHR) for psychosis has been associated with widespread structural brain changes in young adults. The onset of these changes and their subsequent progression over time are not well understood.

Methods:

Rate of brain change over time was investigated in 43 adolescents at UHR for psychosis compared with 30 healthy controls. Brain volumes (total brain, gray matter, white matter [WM], cerebellum, and ventricles), cortical thickness, and voxel-based morphometry were measured at baseline and at follow-up (2 y after baseline) and compared between UHR individuals and controls. Post hoc analyses were done for UHR individuals who became psychotic (N = 8) and those who did not (N = 35).

Results:

UHR individuals showed a smaller increase in cerebral WM over time than controls and more cortical thinning in the left middle temporal gyrus. Post hoc, a more pronounced decrease over time in total brain and WM volume was found for UHR individuals who became psychotic relative to controls and a greater decrease in total brain volume than individuals who were not psychotic. Furthermore, UHR individuals with subsequent psychosis displayed more thinning than controls in widespread areas in the left anterior cingulate, precuneus, and temporo-parieto-occipital area. Volume loss in the individuals who developed psychosis could not be attributed to medication use.

Conclusion:

The development of psychosis during adolescence is associated with progressive structural brain changes around the time of onset. These changes cannot be attributed to (antipsychotic) medication use and are therefore likely to reflect a pathophysiological process related to clinical manifestation of psychosis.     

Corpus callosum area in patients with bipolar disorder with and without psychotic features: an international multicentre study

Background

Previous studies have reported MRI abnormalities of the corpus callosum (CC) in patients with bipolar disorder (BD), although only a few studies have directly compared callosal areas in psychotic versus nonpsychotic patients with this disorder. We sought to compare regional callosal areas in a large international multicentre sample of patients with BD and healthy controls.

Methods

We analyzed anatomic T₁ MRI data of patients with BD-I and healthy controls recruited from 4 sites (France, Germany, Ireland and the United States). We obtained the mid-sagittal areas of 7 CC subregions using an automatic CC delineation. Differences in regional callosal areas between patients and controls were compared using linear mixed models (adjusting for age, sex, handedness, brain volume, history of alcohol abuse/dependence, lithium or antipsychotic medication status, symptomatic status and site) and multiple comparisons correction. We also compared regional areas of the CC between patients with BD with and without a history of psychotic features.

Results

We included 172 patients and 146 controls in our study. Patients with BD had smaller adjusted mid-sagittal CC areas than controls along the posterior body, the isthmus and the splenium of the CC. Patients with a positive history of psychotic features had greater adjusted area of the rostral CC region than those without a history of psychotic features.

Limitations

We found small to medium effect sizes, and there was no calibration technique among the sites.

Conclusion

Our results suggest that BD with psychosis is associated with a different pattern of interhemispheric connectivity than BD without psychosis and could be considered a relevant neuroimaging subtype of BD.     

Brain volumes in psychotic youth with schizophrenia and mood disorders

Background

We sought to test the hypothesis that deficits in grey matter volume are characteristic of psychotic youth with early-onset schizophrenia-spectrum disorders (EOSS) but not of psychotic youth with early-onset mood disorders (EOMD).

Methods

We used magnetic resonance imaging to examine brain volume in 24 psychotic youth (13 male, 11 female) with EOSS (n = 12) or EOMD (n = 12) and 17 healthy controls (10 male, 7 female). We measured the volume of grey and white matter using an automated segmentation program.

Results

After adjustment for age and intracranial volume, whole brain volume was lower in the EOSS patients than in the healthy controls (p = 0.001) and EOMD patients (p = 0.002). The EOSS patients had a deficit in grey matter volume (p = 0.005), especially in the frontal (p = 0.003) and parietal (p = 0.006) lobes, with no significant differences in white matter volume.

Limitations

The main limitations of our study were its small sample size and the inclusion of patients with depression and mania in the affective group.

Conclusion

Adolescents with EOSS have grey matter deficits compared with healthy controls and psychotic adolescents with EOMD. Our results suggest that grey matter deficits are not generally associated with psychosis but may be specifically associated with schizophrenia. Larger studies with consistent methods are needed to reconcile the contradictory findings among imaging studies involving psychotic youth.     

Depressive Symptoms and Brain Metabolite Alterations in Subjects at Ultra-high Risk for Psychosis: A Preliminary Study

Objective

Recent neuroimaging studies have suggested that brain changes occur in subjects at ultra-high risk (UHR) for psychosis while experiencing prodromal symptoms, among which depression may increase the risk of developing a psychotic disorder. The goal of this study is to examine brain metabolite levels in the anterior cingulate cortex, the left dorsolateral prefrontal cortex and the left thalamus in subjects at UHR for psychosis and to compare brain metabolite levels between the UHR subjects with comorbid major depressive disorder and healthy controls.

Methods

Proton magnetic resonance spectroscopy was used to examine brain metabolite levels. Twenty UHR subjects and 20 age- and intelligence quotient (IQ)-matched healthy controls were included in this study.

Results

Overall, no significant differences were observed in any metabolite between the UHR and healthy control group. However, UHR subjects with major depressive disorder showed significantly higher myo-inositol (Ins) levels in the left thalamus, compared to the healthy control.

Conclusion

Our results demonstrate that increased thalamic Ins level is associated with prodromal depressive symptoms. Further longitudinal follow-up studies with larger UHR sample sizes are required to investigate the function of Ins concentrations as a biomarker of vulnerability to psychosis.     

Does neuroanatomy account for superior temporal dysfunction in early psychosis? A multimodal MRI investigation

Background

Neuroimaging studies of ultra-high risk (UHR) and first-episode psychosis (FEP) have revealed widespread alterations in brain structure and function. Recent evidence suggests there is an intrinsic relationship between these 2 types of alterations; however, there is very little research linking these 2 modalities in the early stages of psychosis.

Methods

To test the hypothesis that functional alteration in UHR and FEP participants would be associated with corresponding structural alteration, we examined brain function and structure in these participants as well as in a group of healthy controls using multimodal MRI. The data were analyzed using statistical parametric mapping.

Results

We included 24 participants in the FEP group, 18 in the UHR group and 21 in the control group. Patients in the FEP group showed a reduction in functional activation in the left superior temporal gyrus relative to controls, and the UHR group showed intermediate values. The same region showed a corresponding reduction in grey matter volume in the FEP group relative to controls. However, while the difference in grey matter volume remained significant after including functional activation as a covariate of no interest, the reduction in functional activation was no longer evident after including grey matter volume as a covariate of no interest.

Limitations

Our sample size was relatively small. All participants in the FEP group and 2 in the UHR group had received antipsychotic medication, which may have impacted neurofunction and/or neuroanatomy.

Conclusion

Our results suggest that superior temporal dysfunction in early psychosis is accounted for by a corresponding alteration in grey matter volume. This finding has important implications for the interpretation of functional alteration in early psychosis.     

White matter alterations related to P300 abnormalities in individuals at high risk for psychosis: an MRI-EEG study

Background

Psychosis onset is characterized by white matter and electrophysiologic abnormalities. The relation between these factors in the development of illness is almost unknown. We studied the relation between white matter volumes and P300 in prodromal psychosis.

Methods

We assessed white matter volume (detected using magnetic resonance imaging) and electrophysiologic response during an oddball task (P300) in healthy controls and individuals at high clinical risk for psychosis (with an “at-risk mental state” [ARMS]).

Results

We included 41 controls and 39 patients with an ARMS in our study. A psychotic disorder developed in 26% of the ARMS group within the follow-up period of 2 years. The P300 amplitude was significantly lower in the ARMS group than in the control group. The ARMS group showed reduced volume of white matter underlying the left superior temporal gyrus and the left superior frontal gyrus and increased volume of white matter underlying the right insula and the right angular gyrus compared with controls. Relative to individuals who did not later become psychotic, the subgroup in whom psychosis subsequently developed had a smaller volume of white matter underlying the left precuneus and the right middle temporal gyrus and increased volume in the white matter underlying the right middle frontal gyrus. We observed a significant interaction in the right middle frontal gyrus: white matter volume was negatively associated with P300 amplitude in the ARMS group and positively associated with P300 amplitude in the control group.

Limitations

The voxel-based morphometry method alone cannot determine whether abnormal white matter volumes are due to an altered number of axonal connections or decreased myelination.

Conclusion

P300 abnormalities precede the onset of psychosis and are directly related to white matter alterations, representing a correlate of an increased vulnerability to disease.     

Normal Birth Weight Variation Is Related to Cortical Morphology Across the Psychosis Spectrum

Background:

Normal birth weight variation affects schizophrenia risk and cognitive performance in schizophrenia patients and healthy controls. Brain cortical anatomy is altered in psychotic disorders and in low birth weight subjects, but if birth weight variation relates to cortical morphology across the psychosis spectrum is not known.

Methods:

Magnetic Resonance Imaging brain scans and clinical-, neurocognitive-, and medical birth registry data were collected from 359 adults including patients with a DSM-IV diagnosis of schizophrenia (n = 90, mean age 29.4±10.2 [95% CI], 62% male), bipolar disorder (n = 79, age 29.4±11.8, 39% male) or other psychosis (n = 40, age 26.3±10.0, 56% male), and healthy controls (n = 140, age 30.8±12.0,53% male). We explored the relationship between whole-range birth weight variation and cortical surface area and thickness and their possible associations to cognitive performance.

Results:

Across all groups, lower birth weight was associated with smaller total surface area (t = 3.87, P = .0001), within specific regions of the temporal, parietal, and frontal cortex bilaterally. There were no associations between birth weight and cortical thickness, and no diagnosis by birth weight interaction effects on cortical thickness or surface area. Smaller cortical area (t = 2.50, P = .013) and lower birth weight (t = 2.53, P = .012) were significantly related to poorer working memory performance in all diagnostic groups except schizophrenia.

Conclusion:

Birth weight relates to adult cortical surface area, but not cortical thickness, in patients across the psychosis spectrum and in healthy controls. Cortical area appears to be a diagnosis-independent general marker of early neurodevelopment, with a dose-response association to normal birth weight variation.Key words: Magnetic Resonance Imaging, cortical area, neurodevelopment, schizophrenia, IQ, working memory     

Grey matter alterations in patients with depersonalization disorder: a voxel-based morphometry study

Background

To our knowledge, no whole brain investigation of morphological aberrations in dissociative disorder is available to date. Previous region-of-interest studies focused exclusively on amygdalar, hippocampal and parahippocampal grey matter volumes and did not include patients with depersonalization disorder (DPD). We therefore carried out an explorative whole brain study on structural brain aberrations in patients with DPD.

Methods

We acquired whole brain, structural MRI data for patients with DPD and healthy controls. Voxel-based morphometry was carried out to test for group differences, and correlations with symptom severity scores were computed for grey matter volume.

Results

Our study included 25 patients with DPD and 23 controls. Patients exhibited volume reductions in the right caudate, right thalamus and right cuneus as well as volume increases in the left dorsomedial prefrontal cortex and right somatosensory region that are not a direct function of anxiety or depression symptoms.

Limitations

To ensure ecological validity, we included patients with comorbid disorders and patients taking psychotropic medication.

Conclusion

The results of this first whole brain investigation of grey matter volume in patients with a dissociative disorder indentified structural alterations in regions subserving the emergence of conscious perception. It remains unknown if these alterations are best understood as risk factors for or results of the disorder.     

How Frequent Are Radiological Abnormalities in Patients With Psychosis? A Review of 1379 MRI Scans

Background

The term psychosis refers to a combination of symptoms, without pointing to the origin of these symptoms. In a subset of psychotic patients, symptoms are attributable to an organic disease. It is important to identify these organic causes of psychosis early, as urgent treatment of the primary disease may be required. Some of these underlying organic disorders can be identified on magnetic resonance imaging (MRI) scans. Whether routine screening for all psychotic patients should therefore include MRI scans is still a matter of debate.

Methods

This study investigated the prevalence of clinically relevant abnormalities detected on MRI scans from psychotic patients and a matched control group. We could include MRI scans from 656 psychotic patients and 722 controls. The standard radiological reports of these scans were classified as normal, as a nonrelevant abnormality or as a clinically relevant brain abnormality by means of consensus, blind to diagnosis.

Results

A normal aspect of the brain was reported in 74.4% of the patients and in 73.4% of the controls. We found clinically relevant pathology in 11.1% of the patients and in 11.8% of the controls. None of the neuropathological findings observed in the patients was interpreted as a possible substrate for organic psychosis. Brain abnormalities that were classified as not clinically relevant were identified in 14.5% of the patients and in 14.8% of the controls.

Conclusions

This suggests that MRI brain scans are not an essential part of routine screening for psychotic patients.     

Orbito-Frontal Cortex Volumes in Panic Disorder

Objective

Given the association between the pathophysiology of panic disorder and prefrontal cortex function, we aimed to perform a volumetric MRI study in patients with panic disorder and healthy controls focusing on the in vivo neuroanatomy of the OFC.

Methods

Twenty right-handed patients with panic disorder and 20 right-handed healthy control subjects were studied. The volumes of whole brain, total white and gray matters, and OFC were measured by using T1-weighted coronal MRI images, with 1.5-mm-thick slices, at 1.5T. In addition, for psychological valuation, Hamilton Depression Rating (HDRS) and Panic Agoraphobia Scales (PAS) were administered.

Results

Unadjusted mean volumes of the whole brain volume, total white and gray matter were not different between the patients and healthy controls while the patient group had significantly smaller left (t=-6.70, p<0.0001) and right (t=-5.86, p<0.0001) OFC volumes compared with healthy controls.

Conclusion

Our findings indicate an alteration of OFC morphology in the panic disorder and suggest that OFC abnormalities may be involved in the pathophysiology of panic disorder.     

Emotion recognition and experience in Huntington disease: a voxel-based morphometry study

Background

The neuroanatomic basis of affective processing deficits in Huntington disease is insufficiently understood. We investigated whether Huntington disease–related deficits in emotion recognition and experience are associated with specific changes in grey matter volume.

Method

We assessed grey matter volume in symptomatic patients with Huntington disease and healthy controls using voxel-based morphometry, and we correlated regional grey matter volume with participants’ affective ratings.

Results

We enrolled 18 patients with Huntington disease and 18 healthy controls in our study. Patients with Huntington disease showed normal affective experience but impaired recognition of negative emotions (disgust, anger, sadness). The patients perceived the emotions as less intense and made more classification errors than controls. These deficits were correlated with regional atrophy in emotion-relevant areas (insula, orbitofrontal cortex) and in memory-relevant areas (dorsolateral prefrontal cortex, hippocampus).

Limitations

Our study was limited by the small sample size and the resulting modest statistical power relative to the number of tests.

Conclusion

Our study sheds new light on the importance of a cognitive–affective brain circuit involved in the affect recognition impairment in patients with Huntington disease.     

Hippocampus and amygdala volumes in patients with borderline personality disorder with or without posttraumatic stress disorder

Background

Several studies have investigated volumetric brain changes in patients with posttraumatic stress disorder (PTSD) and borderline personality disorder (BPD). Both groups exhibit volume reductions of the hippocampus and amygdala. Our aim was to investigate the influence of comorbid PTSD on hippocampus and amygdala volumes in patients with BPD.

Methods

We compared 2 groups of unmedicated female patients with BPD (10 with and 15 without comorbid PTSD) and 25 healthy female controls. We used T₁- and T₂-weighted magnetic resonance images for manual tracing and 3-dimensional reconstruction of the hippocampus and amygdala.

Results

Hippocampus volumes of patients with BPD and PTSD were smaller than those of healthy controls. However, there was no significant difference between patients with BPD but without PTSD and controls. Impulsiveness was positively correlated with hippocampus volumes in patients with BPD.

Limitations

Our study did not allow for disentangling the effects of PTSD and traumatization. Another limitation was the relatively small sample size.

Conclusion

Our findings highlight the importance of classifying subgroups of patients with BPD. Comorbid PTSD may be related to volumetric alterations in brain regions that are of central importance to our understanding of borderline psychopathology.     

Event-related potentials and changes of brain rhythm oscillations during working memory activation in patients with first-episode psychosis

Background

Earlier contributions have documented significant changes in sensory, attention-related endogenous event-related potential (ERP) components and θ band oscillatory responses during working memory activation in patients with schizophrenia. In patients with first-episode psychosis, such studies are still scarce and mostly focused on auditory sensory processing. The present study aimed to explore whether subtle deficits of cortical activation are present in these patients before the decline of working memory performance.

Methods

We assessed exogenous and endogenous ERPs and frontal θ event-related synchronization (ERS) in patients with first-episode psychosis and healthy controls who successfully performed an adapted 2-back working memory task, including 2 visual n-back working memory tasks as well as oddball detection and passive fixation tasks.

Results

We included 15 patients with first-episode psychosis and 18 controls in this study. Compared with controls, patients with first-episode psychosis displayed increased latencies of early visual ERPs and phasic θ ERS culmination peak in all conditions. However, they also showed a rapid recruitment of working memory–related neural generators, even in pure attention tasks, as indicated by the decreased N200 latency and increased amplitude of sustained θ ERS in detection compared with controls.

Limitations

Owing to the limited sample size, no distinction was made between patients with first-episode psychosis with positive and negative symptoms. Although we controlled for the global load of neuroleptics, medication effect cannot be totally ruled out.

Conclusion

The present findings support the concept of a blunted electroencephalographic response in patients with first-episode psychosis who recruit the maximum neural generators in simple attention conditions without being able to modulate their brain activation with increased complexity of working memory tasks.     

Nonlinear analysis of electroencephalogram at rest and during cognitive tasks in patients with schizophrenia

Background

In spite of the large number of studies on schizophrenia, a full understanding of its core pathology still eludes us. The application of the nonlinear theory of electroencephalography (EEG) analysis provides an interesting tool to differentiate between physiologic conditions (e.g., resting state and mathematical task) and normal and pathologic brain activities. The aim of the present study was to investigate nonlinear EEG activity in patients with schizophrenia.

Methods

We recorded 19-lead EEGs in patients with stable schizophrenia and healthy controls under 4 different conditions: eyes closed, eyes open, forward counting and backward counting. A nonlinear measure of complexity was calculated by means of correlation dimension (D2).

Results

We included 17 patients and 17 controls in our analysis. Comparing the 2 populations, we observed greater D2 values in the patient group. In controls, increased D2 values were observed during active states (eyes open and the 2 cognitive tasks) compared with baseline conditions. This increase of brain complexity, which can be interpreted as an increase of information processing and integration, was not preserved in the patient population.

Limitations

Patients with schizophrenia were taking antipsychotic medications, so the presence of medication effects cannot be excluded.

Conclusion

Our results suggest that patients with schizophrenia present changes in brain activity compared with healthy controls, and this pathologic alteration can be successfully studied with nonlinear EEG analysis.     

Cognitive Biases Questionnaire for Psychosis

Objective:

The Cognitive Biases Questionnaire for psychosis (CBQp) was developed to capture 5 cognitive distortions (jumping to conclusions, intentionalising, catastrophising, emotional reasoning, and dichotomous thinking), which are considered important for the pathogenesis of psychosis. Vignettes were adapted from the Cognitive Style Test (CST),¹ relating to “Anomalous Perceptions” and “Threatening Events” themes.

Method:

Scale structure, reliability, and validity were investigated in a psychosis group, and CBQp scores were compared with those of depressed and healthy control samples.

Results:

The CBQp showed good internal consistency and test-retest reliability. The 5 biases were not independent, with a 2-related factor scale providing the best fit. This structure suggests that the CBQp assesses a general thinking bias rather than distinct cognitive errors, while Anomalous Perception and Threatening Events theme scores can be used separately. Total CBQp scores showed good convergent validity with the CST, but individual biases were not related to existing tasks purporting to assess similar reasoning biases. Psychotic and depressed populations scored higher than healthy controls, and symptomatic psychosis patients scored higher than their nonsymptomatic counterparts, with modest relationships between CBQp scores and symptom severity once emotional disorders were partialled out. Anomalous Perception theme and Intentionalising bias scores showed some specificity to psychosis.

Conclusions:

Overall, the CBQp has good psychometric properties, although it is likely that it measures a different construct to existing tasks, tentatively suggested to represent a bias of interpretation rather than reasoning, judgment or decision-making processes. It is a potentially useful tool in both research and clinical arenas.Key words: schizophrenia, thinking errors, delusions, hallucinations, cognitive behavior therapy for psychosis     

Nightmares in Patients With Psychosis: The Relation With Sleep,Psychotic, Affective,and Cognitive Symptoms

Objective:

To examine the prevalence of nightmares in people with psychosis and to describe the link between nightmares and sleep quality, psychotic, affective, and cognitive symptoms.

Methods:

Forty participants with psychotic symptoms completed an assessment of nightmares, sleep quality, positive symptoms of psychosis, affect, posttraumatic stress, social functioning, and working memory.

Results:

Among the patients, 55% reported weekly distressing nightmares. Experience of more frequent nightmares was related to poorer sleep quality and sleep efficiency. More distressing nightmares were positively associated with greater delusional severity, depression, anxiety, stress, and difficulties with working memory.

Conclusions:

Nightmares might be common in those with psychosis and are associated with increased day- and nighttime impairment. Future research should investigate treatments for nightmares, for people presenting with psychotic symptoms.     

Effect of childhood maltreatment on brain structure in adult patients with major depressive disorder and healthy participants

Background

Childhood maltreatment has been found to play a crucial role in the development of psychiatric disorders. However, whether childhood maltreatment is associated with structural brain changes described for major depressive disorder (MDD) is still a matter of debate. The aim of this study was to investigate whether patients with MDD and a history of childhood maltreatment display more structural changes than patients without childhood maltreatment or healthy controls.

Methods

Patients with MDD and healthy controls with and without childhood maltreatment experience were investigated using high-resolution magnetic resonance imaging (MRI), and data were analyzed using voxel-based morphometry.

Results

We studied 37 patients with MDD and 46 controls. Grey matter volume was significantly decreased in the hippocampus and significantly increased in the dorsomedial prefrontal cortex (DMPFC) and the orbitofrontal cortex (OFC) in participants who had experienced childhood maltreatment compared with those who had not. Patients displayed smaller left OFC and left DMPFC volumes than controls. No significant difference in hippocampal volume was evident between patients with MDD and healthy controls. In regression analyses, despite effects from depression, age and sex on the DMPFC, OFC and hippocampus, childhood maltreatment was found to independently affect these regions.

Limitations

The retrospective assessment of childhood maltreatment; the natural problem that patients experienced more childhood maltreatment than controls; and the restrictions, owing to sample size, to investigating higher order interactions among factors are discussed as limitations.

Conclusion

These results suggest that early childhood maltreatment is associated with brain structural changes irrespective of sex, age and a history of depression. Thus, the study highlights the importance of childhood maltreatment when investigating brain structures.     

Increased Laterality of the Thalamus in Children and Adolescents with Asperger's Disorder: An MRI and Proton Spectroscopy Study

Objective

Thalamic abnormalities have been reported in people with pervasive developmental disorders (PDD) including Asperger''s Disorder (ASP). The aim of the present study was to compare the volume and volume fraction of the thalamus and the metabolite concentrations in children and adolescents with ASP using the magnetic resonance imaging and proton magnetic resonance spectroscopy. Additionally, the relationships between thalamic abnormalities and clinical features were examined.

Methods

Volume and volume fractional and metabolic measurements of bilateral thalamus were collected from 15 boys with ASP with a total IQ over 70 (age range 7-18 years, mean age 11.6±3.79 years), and 15 healthy controls matching age, sex and IQ. The thalamic volumes, hemisphere volumes and total brain volumes (TBV) were estimated using the stereological methods on magnetic resonance images. Chemical metabolites of thalamus were evaluated by ¹H spectroscopy.

Results

No differences in thalamic volumes, volume fractions and metabolites were observed between the groups. There were significant correlation between thalamic volume and total brain volume in both groups. The ASP group showed a significant left-minus-right thalamus difference as well as a significantly greater laterality index. In addition, a significant correlation between the laterality index and Autism Behavior Checklist language scores was observed.

Conclusion

Findings from this investigation point to a significant increase in laterality of the thalamus and a relationship with language problems in individuals with ASP. Our findings suggest that thalamic abnormalities may be related to mild language problems observed in ASP.