Reduced anterior internal capsule and thalamic volumes in first-episode psychosis

Unilateral anterior capsulotomy combined with deep brain stimulation for Parkinson's disease psychosis and motor dysfunctions

Psychosis is a frequent and debilitating non-motor symptom of Parkinson's disease (PD). This study aimed to evaluate the availability of unilateral anterior capsulotomy combined with subthalamic nucleus deep brain stimulation (STN-DBS) in managing advanced PD patients comorbid with psychosis. Five advanced PD patients with psychosis who had been treated with unilateral anterior capsulotomy combined with bilateral STN-DBS were assessed. The positive subscore of the Positive and Negative Syndrome Scale (PANSS) and the Unified Parkinson's Disease Rating Scale III (UPDRS-III) were used to assess the efficacy parameter of psychosis and the improved motor symptoms, respectively. The quality of life (QoL) was accessed by an 8-item Parkinson's disease Questionnaire (PDQ-8). Clinical outcome assessments were performed at baseline and follow-ups after one or two years. Significant improvement was observed in PD patients during follow-up after the combined treatment. The positive subscore of PANSS improved by 13.4 (5.7) (mean (SD), p = 0.006). Item P1 (delusions) and Item P3 (hallucinations) of the PANSS improved by 5.0 (0.71) (p < 0.0001) and 3.6 (0.89) (p = 0.0008), respectively. Furthermore, the motor symptoms improved by 32.4 (5.7) (UPDRS-III, p = 0.0002), and the QoL improved by 6.4 (3.8) (PDQ-8, p = 0.021). No significant side effects or complications occurred during the study. For advanced PD patients with refractory psychosis, unilateral anterior capsulotomy combined with bilateral STN-DBS improved PD psychosis and motor dysfunction, providing an effective therapeutic option for such patients.

Combined fractional anisotropy and subcortical volumetric deficits in patients with mild-to-moderate depression: Evidence from the treatment of antidepressant traditional Chinese medicine

Numerous neuroimaging studies have demonstrated that diverse brain structural plasticity could occur in a human brain during a depressive episode. However, there is a lack of knowledge regarding the underlying mechanisms of mild-to-moderate depression (MMD), especially the changes of brain structural characteristics after treatment with the Shuganjieyu capsule (SG), a kind of traditional Chinese medicine that has been recommended for the specialized treatment of MMD. In this study, we investigated the structural brain plasticity in MMD that have been undergoing 8 weeks of SG treatment compared with age- and sex-matched healthy controls (HCs) and assessed the relationship between these brain structural alternations and clinical symptoms in MMD. At the baseline, we found that: (1) fractional anisotropy (FA) values in patients with MMD were found to be significantly increased in the regions of anterior limb of internal capsule (ALIC) [MNI coordinates: Peak (x/y/z) = 102, 126, 77; MMD FA_peak (Mean ± SD) = 0.621 ± 0.043; HCs FA_peak (Mean ± SD) = 0.524 ± 0.052; MMD > HCs, t = 9.625, p < 0.001] and posterior limb of internal capsule (PLIC) [MNI coordinates: Peak (x/y/z) = 109, 117, 87; MMD FA_peak (Mean ± SD) = 0.694 ± 0.042; HCs FA_peak (Mean ± SD) = 0.581 ± 0.041; MMD > HCs, t = 12.90, p < 0.001], and FA values were significantly positively correlated with HAMD scores in patients with MMD. (2) Patients with MMD showed smaller gray matter volume (GMV) of the dorsolateral prefrontal cortex (DLPFC), frontal cortex, occipital cortex, and precuneus, and the GMV of DLPFC was negatively correlated with HAMD scores. After SG treatment, we found that (1) the HAMD scores decreased; (2) FA values were significantly decreased in the regions of the ALIC and PLIC compared to those at baseline and TBSS revealed no significant differences in FA values between patients with MMD and HCs. (3) The structural characteristics of DLPFC in patients with MMD obtained at the 8th week were improved, e.g., no significant differences in GMV of DLPFC between the two groups. Taken together, our results provided neuroimaging evidence suggesting that SG is an effective treatment for patients with MMD. Moreover, alterations of GMV after 8 weeks of SG treatment indicated a potential modulation mechanism in brain structural plasticity within the DLPFC in patients with MMD.

Neural mechanisms of psychosis vulnerability and perceptual abnormalities in the ALS-FTD spectrum

OBJECTIVE

The aims of this study were to (i) explore psychotic experiences across the entire amyotrophic lateral sclerosis-frontotemporal dementia (ALS-FTD) spectrum from a clinical and genetic perspective, (ii) determine the rate of abnormal perceptual experiences across the five sensory modalities and (iii) explore the neurobiological factors that lead to psychosis vulnerability in ALS-FTD.

METHODS

In a prospective case-controlled study design, 100 participants were enrolled including ALS (n = 37, 24% satisfied criteria for ALS-Plus), ALS-FTD (n = 11), bvFTD (n = 27) and healthy controls (n = 25). Psychotic experiences, perceptual abnormalities and psychosocial factors were determined by means of the clinical interview and carer and patient reports. Voxel-based morphometry analyses determined atrophy patterns in patients experiencing psychosis-like experiences and other perceptual abnormalities.

RESULTS

The rates of psychotic experiences and abnormalities of perception in each sensory modality were high across the entire ALS-FTD continuum. The rate was highest in those with C9orf72 expansions. Rates were also high in patients with pure ALS including psychosis measured by carer-based reports (18%) and self-report measures of psychotic-like experiences (21%). In an ENTER regression model, social anxiety and ACE-III scores were the best predictors of psychosis proneness, accounting for 44% of the score variance. Psychosis-like experiences and perceptual abnormalities were associated with a predominantly frontal and temporal pattern of atrophy that extended to the cerebellum and centred on the anterior thalamus.

INTERPRETATION

The model for psychosis proneness in ALS-FTD likely includes complex interactions between cognitive, social and neurobiological factors that determine vulnerability to psychosis and that may have relevance for individualised patient management.

Multimodal MRI assessment for first episode psychosis: A major change in the thalamus and an efficient stratification of a subgroup

Multi‐institutional brain imaging studies have emerged to resolve conflicting results among individual studies. However, adjusting multiple variables at the technical and cohort levels is challenging. Therefore, it is important to explore approaches that provide meaningful results from relatively small samples at institutional levels. We studied 87 first episode psychosis (FEP) patients and 62 healthy subjects by combining supervised integrated factor analysis (SIFA) with a novel pipeline for automated structure‐based analysis, an efficient and comprehensive method for dimensional data reduction that our group recently established. We integrated multiple MRI features (volume, DTI indices, resting state fMRI—rsfMRI) in the whole brain of each participant in an unbiased manner. The automated structure‐based analysis showed widespread DTI abnormalities in FEP and rs‐fMRI differences between FEP and healthy subjects mostly centered in thalamus. The combination of multiple modalities with SIFA was more efficient than the use of single modalities to stratify a subgroup of FEP (individuals with schizophrenia or schizoaffective disorder) that had more robust deficits from the overall FEP group. The information from multiple MRI modalities and analytical methods highlighted the thalamus as significantly abnormal in FEP. This study serves as a proof‐of‐concept for the potential of this methodology to reveal disease underpins and to stratify populations into more homogeneous sub‐groups.

The anterior limb of the internal capsule: Anatomy, function, and dysfunction

The last two decades have seen a re-emergence of neurosurgery for severe, refractory psychiatric diseases, largely due to the advent of more precise and safe operative techniques. Nevertheless, the optimal targets for these surgeries remain a matter of debate, and are often grandfathered from experiences in the late 20th century. To better explore the rationale for one target in particular - the anterior limb of the internal capsule (ALIC) - we comprehensively reviewed all available literature on its role in the pathophysiology and treatment of mental illness. We first provide an overview of its functional anatomy, followed by a discussion on its role in several prevalent psychiatric diseases. Given its structural integration into the limbic system and involvement in a number of cognitive and emotional processes, the ALIC is a robust target for surgical treatment of refractory psychiatric diseases. The advent of novel neuroimaging techniques, coupled with image-guided therapeutics and neuromodulatory treatments, will continue to enable study on the ALIC in mental illness.

Alterations in Schizophrenia-Associated Genes Can Lead to Increased Power in Delta Oscillations

Genome-wide association studies have implicated many ion channels in schizophrenia pathophysiology. Although the functions of these channels are relatively well characterized by single-cell studies, the contributions of common variation in these channels to neurophysiological biomarkers and symptoms of schizophrenia remain elusive. Here, using computational modeling, we show that a common biomarker of schizophrenia, namely, an increase in delta-oscillation power, may be a direct consequence of altered expression or kinetics of voltage-gated ion channels or calcium transporters. Our model of a circuit of layer V pyramidal cells highlights multiple types of schizophrenia-related variants that contribute to altered dynamics in the delta-frequency band. Moreover, our model predicts that the same membrane mechanisms that increase the layer V pyramidal cell network gain and response to delta-frequency oscillations may also cause a deficit in a single-cell correlate of the prepulse inhibition, which is a behavioral biomarker highly associated with schizophrenia.

Variation in fourteen brain structure volumes in schizophrenia: A comprehensive meta-analysis of 246 studies

Despite hundreds of structural MRI studies documenting smaller brain volumes on average in schizophrenia compared to controls, little attention has been paid to group differences in the variability of brain volumes. Examination of variability may help interpret mean group differences in brain volumes and aid in better understanding the heterogeneity of schizophrenia. Variability in 246 MRI studies was meta-analyzed for 13 structures that have shown medium to large mean effect sizes (Cohen's d≥0.4): intracranial volume, total brain volume, lateral ventricles, third ventricle, total gray matter, frontal gray matter, prefrontal gray matter, temporal gray matter, superior temporal gyrus gray matter, planum temporale, hippocampus, fusiform gyrus, insula; and a control structure, caudate nucleus. No significant differences in variability in cortical/subcortical volumes were detected in schizophrenia relative to controls. In contrast, increased variability was found in schizophrenia compared to controls for intracranial and especially lateral and third ventricle volumes. These findings highlight the need for more attention to ventricles and detailed analyses of brain volume distributions to better elucidate the pathophysiology of schizophrenia.

Connectivity-based parcellation of the anterior limb of the internal capsule

The anterior limb of the internal capsule (ALIC) is an important locus of frontal-subcortical fiber tracts involved in cognitive and limbic feedback loops. However, the structural organization of its component fiber tracts remains unclear. Therefore, although the ALIC is a promising target for various neurosurgical procedures for psychiatric disorders, more precise understanding of its organization is required to optimize target localization. Using diffusion tensor imaging (DTI) collected on healthy subjects by the Human Connectome Project (HCP), we generated parcellations of the ALIC by dividing it according to structural connectivity to various frontal regions. We then compared individuals' parcellations to evaluate the ALIC's structural consistency. All 40 included subjects demonstrated a posterior-superior to anterior-inferior axis of tract organization in the ALIC. Nonetheless, subdivisions of the ALIC were found to vary substantially, as voxels in the average parcellation were accurately assigned for a mean of only 66.2% of subjects. There were, however, some loci of consistency, most notably in the region maximally connected to orbitofrontal cortex. These findings clarify the highly variable organization of the ALIC and may represent a tool for patient-specific targeting of neuromodulation. Hum Brain Mapp 38:6107-6117, 2017. © 2017 Wiley Periodicals, Inc.

Organization of the Anterior Limb of the Internal Capsule in the Rat

Dysfunction of the orbitofrontal (OFC) and anterior cingulate (ACC) cortices has been linked with several psychiatric disorders, including obsessive-compulsive disorder, major depressive disorder, posttraumatic stress disorder, and addiction. These conditions are also associated with abnormalities in the anterior limb of the internal capsule, the white matter (WM) bundle carrying ascending and descending fibers from the OFC and ACC. Furthermore, deep-brain stimulation (DBS) for psychiatric disorders targets these fibers. Experiments in rats provide essential information on the mechanisms of normal and abnormal brain anatomy, including WM composition and perturbations. However, whereas descending prefrontal cortex (PFC) fibers in primates form a well defined and topographic anterior limb of the internal capsule, the specific locations and organization of these fibers in rats is unknown. We address this gap by analyzing descending fibers from injections of an anterograde tracer in the rat ACC and OFC. Our results show that the descending PFC fibers in the rat form WM fascicles embedded within the striatum. These bundles are arranged topographically and contain projections, not only to the striatum, but also to the thalamus and brainstem. They can therefore be viewed as the rat homolog of the primate anterior limb of the internal capsule. Furthermore, mapping these projections allows us to identify the fibers likely to be affected by experimental manipulations of the striatum and the anterior limb of the internal capsule. These results are therefore essential for translating abnormalities of human WM and effects of DBS to rodent models.SIGNIFICANCE STATEMENT Psychiatric diseases are linked to abnormalities in specific white matter (WM) pathways, and the efficacy of deep-brain stimulation relies upon activation of WM. Experiments in rodents are necessary for studying the mechanisms of brain function. However, the translation of results between primates and rodents is hindered by the fact that the organization of descending WM in rodents is poorly understood. This is especially relevant for the prefrontal cortex, abnormal connectivity of which is central to psychiatric disorders. We address this gap by studying the organization of descending rodent prefrontal pathways. These fibers course through a subcortical structure, the striatum, and share important organization principles with primate WM. These results allow us to model primate WM effectively in the rodent.

Sex/gender differences in the brain and cognition in schizophrenia

The early conceptualizations of schizophrenia have noted some sex/gender differences in epidemiology and clinical expression of the disorder. Over the past few decades, the interest in differences between male and female patients has expanded to encompass brain morphology and neurocognitive function. Despite some variability and methodological shortcomings, a few patterns emerge from the available literature. Most studies of gross neuroanatomy show more enlarged ventricles and smaller frontal lobes in men than in women with schizophrenia; finding reflecting normal sexual dimorphism. In comparison, studies of brain asymmetry and specific corticolimbic structures, suggest a disturbance in normal sexual dimorphism. The neurocognitive findings are somewhat consistent with this picture. Studies of cognitive functions mediated by the lateral frontal network tend to show sex differences in patients which are in the same direction as those observed in the general population, whereas studies of processes mediated by the corticolimbic system more frequently reveal reversal of normal sexual dimorphisms. These trends are faint and future research would need to delineate neurocognitive differences between men and women with various subtypes of schizophrenia (e.g., early versus late onset), while taking into consideration hormonal status and gender of tested participants.

Disrupted thalamo-cortical connectivity in schizophrenia: a morphometric correlation analysis

Increasing studies have implicated the thalamus in schizophrenia, supporting the view that this structure has an important role in this disorder. Given that extensive reciprocal connections exist between the thalamus and the cerebral cortex, it is believed that disruptions of the thalamo-cortical connections may underlie the multiplicity of schizophrenic symptoms. Therefore, assessing the relationship between the thalamus and the neocortex may provide new insights into the pathophysiology of schizophrenia. We analyzed magnetic resonance images from a sample of 101 schizophrenic patients and 101 healthy controls. By assessing the correlation between the thalamic volume and cortical thickness at each vertex on the cortical surface, a thalamo-cortical network was obtained for each group. We compared the patterns of thalamo-cortical connectivity between the two groups. Compared with healthy controls, less distributed cortical regions were identified in the thalamo-cortical network in patients with schizophrenia. Vertex-wise comparison revealed decreased thalamo-cortical connectivity in bilateral inferior frontal gyrus, the left superior temporal gyrus and the right parieto-occipital region in schizophrenia. The observed disruptions in thalamo-cortical connectivity might be the substrate underlying the wide range of schizophrenic symptoms and provide further evidence to support the notion of schizophrenia as a disorder of brain dysconnectivity.

fMRI assessment of thalamocortical connectivity during attentional performance

Functional magnetic resonance imaging (fMRI) studies have shown dysfunction in key areas associated with the thalamocortical circuit in patients with schizophrenia. This study examined the functional connectivity involving the frontal-thalamic circuitry during a spatial focusing-of-attention task in 18 unmedicated patients with schizophrenia and 38 healthy controls. Functional connectivity was analyzed by assigning seed regions (in the thalamic nuclei (mediodorsal nucleus (MDN), pulvinar, anterior nucleus (AN)), the dorsolateral prefrontal cortex (Brodmann areas 9 and 46), and the caudate), and correlating their respective activity with that in the non-seed regions voxel-wise. Functional connectivity analysis demonstrated that functional connectivity was significantly impaired in patients, e.g., between the right pulvinar and regions such as the prefrontal and temporal cortices and the cerebellum. On the other hand, enhanced functional connectivity was found in patients, e.g., between the AN and regions such as the prefrontal and temporal cortices. In addition, the patients had significantly lower task performance and less (but non-significant) brain activation than those of controls. These results revealed disturbed functional integration in schizophrenia, and suggested that the functional connectivity abnormalities in the thalamocortical circuitry, especially the frontal-thalamic circuitry, may underlie the attention deficits in schizophrenia patients. Further, this study suggested that functional connectivity analysis might be more sensitive than brain activation analysis in detecting the functional abnormalities in schizophrenia.

Anterior limb of the internal capsule in schizophrenia: a diffusion tensor tractography study

Thalamo-cortical feedback loops play a key role in the processing and coordination of processing and integration of perceptual inputs and outputs, and disruption in this connection has long been hypothesized to contribute significantly to neuropsychological disturbances in schizophrenia. To test this hypothesis, we applied diffusion tensor tractography to 18 patients suffering schizophrenia and 20 control subjects. Fractional anisotropy (FA) was evaluated in the bilateral anterior and posterior limbs of the internal capsule, and correlated with clinical and neurocognitive measures. Patients diagnosed with schizophrenia showed significantly reduced FA bilaterally in the anterior but not the posterior limb of the internal capsule, compared with healthy control subjects. Lower FA correlated with lower scores on tests of declarative episodic memory in the patient group only. These findings suggest that disruptions, bilaterally, in thalamo-cortical connections in schizophrenia may contribute to disease-related impairment in the coordination of mnemonic processes of encoding and retrieval that are vital for efficient learning of new information.

Reduced volume in the anterior internal capsule but its maintained correlation with the frontal gray matter in subjects at ultra-high risk for psychosis

The anterior limb of the internal capsule (ALIC), which interconnects with the frontal cortex and thalamus, is volumetrically altered in schizophrenia patients. However, it is unclear whether an abnormal ALIC volume is apparent prior to the onset of schizophrenia and whether this aberrant ALIC volume is related to the frontal gray matter in individuals at ultra-high risk (UHR) for psychosis. We used magnetic resonance imaging of 43 UHR subjects, 36 schizophrenia patients, and 42 healthy controls to investigate manually traced ALIC volumes. Additionally, we evaluated the correlation between the ALIC volume and the frontal gray matter. Significantly reduced ALIC volumes were observed in the UHR and schizophrenia groups compared to the healthy controls. However, the volume of the frontal gray matter was decreased only in the schizophrenia group. A positive correlation between the volumes in the ALIC and frontal gray matter found in healthy controls was maintained only in UHR subjects. In addition, a negative correlation between the total scores on the Positive and Negative Syndrome Scale and the ALIC volumes was observed only in schizophrenia patients. An aberrant ALIC volume but its maintained correlation with the interconnecting frontal lobe was present prior to the onset of full psychosis, indicating the prodromal phase of psychosis.

Anterior limb of the internal capsule in schizotypal personality disorder: fiber-tract counting, volume, and anisotropy

Mounting evidence suggests that white matter abnormalities and altered subcortical-cortical connectivity may be central to the pathology of schizophrenia (SZ). The anterior limb of the internal capsule (ALIC) is an important thalamo-frontal white-matter tract shown to have volume reductions in SZ and to a lesser degree in schizotypal personality disorder (SPD). While fractional anisotropy (FA) and connectivity abnormalities in the ALIC have been reported in SZ, they have not been examined in SPD. In the current study, magnetic resonance (MRI) and diffusion tensor imaging (DTI) were obtained in age- and sex-matched individuals with SPD (n=33) and healthy controls (HCs; n=38). The ALIC was traced bilaterally on five equally spaced dorsal-to-ventral axial slices from each participant's MRI scan and co-registered to DTI for the calculation of FA. Tractography was used to examine tracts between the ALIC and two key Brodmann areas (BAs; BA10, BA45) within the dorsolateral prefrontal cortex (DLPFC). Compared with HCs, the SPD participants exhibited (a) smaller relative volume at the mid-ventral ALIC slice level but not the other levels; (b) normal FA within the ALIC; (c) fewer relative number of tracts between the most-dorsal ALIC levels and BA10 but not BA45 and (d) fewer dorsal ALIC-DLPFC tracts were associated with greater symptom severity in SPD. In contrast to prior SZ studies that report lower FA, individuals with SPD show sparing. Our findings are consistent with a pattern of milder thalamo-frontal dysconnectivity in SPD than schizophrenia.

White matter tract abnormalities in first-episode psychosis

Fibers connecting fronto-temporal and fronto-medial structures that pass through the anterior limb of the internal capsule (ALIC) subserve executive and psychomotor functioning. Both of these functions are adversely affected in schizophrenia, and may be abnormal at illness onset. In a study of first-episode psychosis, we used diffusion tensor imaging (DTI) and cognitive testing to examine ALIC integrity. Fourteen early psychosis patients and 29 healthy volunteers were included. Symptoms were assessed with the Positive and Negative Syndromes Scale (PANSS). All structural and diffusion scans were acquired on a GE Signa 1.5T scanner. A T1-weighted 3D FSPGR Inversion Recovery imaging series was acquired for manual seeding in structural space. Diffusion tensor imaging (DTI) was performed, and all DTI images were co-registered to structural space. Seeds were manually drawn bilaterally on the coronal plane at a specified location. Diffusion images were post-processed for subsequent Tract-based Spatial Statistics (TBSS) analysis. First-episode psychosis patients had significantly smaller fronto-medial and fronto-temporal AIC tract volumes compared to healthy volunteers on the left and the right (p-values<0.04). No differences in mean fractional anisotropy (FA) were seen within either left or right tracts (p-values>0.05), nor did TBSS reveal any other differences in FA values between groups in other regions. Relationships between tract volumes and symptom severity were not observed in this study.

Functional and anatomical connectivity abnormalities in cognitive division of anterior cingulate cortex in schizophrenia

Introduction

Current pathophysiological theories of schizophrenia highlight the role of altered brain functional and anatomical connectivity. The cognitive division of anterior cingulate cortex (ACC-cd) is a commonly reported abnormal brain region in schizophrenia for its importance in cognitive control process. The aim of this study was to investigate the functional and anatomical connectivity of ACC-cd and its cognitive and clinical manifestation significance in schizophrenia by using the resting-state functional magnetic resonance imaging (fMRI) and the diffusion tensor imaging (DTI).

Methods

Thirty-three medicated schizophrenics and 30 well-matched health controls were recruited. Region-of-interest (ROI)-based resting-state functional connectivity analysis and Tract-Based Spatial Statistics (TBSS) were performed on 30 patients and 30 controls, and 24 patients and 29 controls, respectively. The Pearson correlation was performed between the imaging measures and the Stroop performance and scores of the Positive and Negative Syndrome Scale (PANSS), respectively.

Results

Patients with schizophrenia showed significantly abnormal in the functional connectivity and its hemispheric asymmetry of the ACC-cd with multiple brain areas, e.g., decreased positive connectivity with the bilateral putamen and caudate, increased negative connectivity with the left posterior cingulated cortex (PCC), increased asymmetry of connectivity strength with the contralateral inferior frontal gyrus (IFG). The FA of the right anterior cingulum was significantly decreased in patients group (p = 0.014). The abnormal functional and structural connectivity of ACC-cd were correlated with Stroop performance and the severity of the symptoms in patients.

Conclusions

Our results suggested that the abnormal connectivity of the ACC-cd might play a role in the cognitive impairment and clinical symptoms in schizophrenia.

Fractional anisotropy and radial diffusivity: diffusion measures of white matter abnormalities in the anterior limb of the internal capsule in schizophrenia

INTRODUCTION

Higher cognitive functioning is mediated by frontal-subcortical cognitive and limbic feedback sub-loops. The thalamo-cortical projection through the anterior limb of the internal capsule (ALIC) serves as the final step in these feedback sub-loops. We evaluated abnormalities in the ALIC fiber tract in schizophrenia using both structural MRI and diffusion tensor imaging (DTI).

METHODS

20 chronic schizophrenia patients and 22 male, normal controls group matched for handedness, age, and parental SES, underwent structural and DTI brain imaging on a 1.5 Tesla GE system. We manually measured ALIC volume normalized for intracranial contents (ICC) using structural brain images and then registered these high resolution structural brain scan derived ALIC label maps to DTI space allowing for the measurement in the ALIC of diffusion indices including, fractional anisotropy (FA) mean diffusivity (MD), radial diffusivity (RD), and axial diffusivity (AD).

RESULTS

We found in the ALIC of chronic schizophrenia subjects, compared with normal controls, bilaterally lower FA and bilaterally higher RD, but no differences in AD, MD, or relative volume. Cognitive correlations in schizophrenia patients showed, in particular, that higher left ALIC FA correlated positively with better verbal and nonverbal declarative/episodic memory performance.

DISCUSSION

Using a novel approach to assess both diffusion and volume measures in the ALIC in schizophrenia, we found abnormalities in measures of diffusion, but not volume, supporting their importance as sensitive indices of abnormalities in white matter fiber bundles in schizophrenia. Our findings also support the role of ALIC white matter tract FA abnormalities in declarative/episodic memory in schizophrenia.

Understanding aberrant white matter development in schizophrenia: an avenue for therapy?

Although historically gray matter changes have been the focus of neuropathological and neuroradiological studies in schizophrenia, in recent years an increasing body of research has implicated white matter structures and its constituent components (axons, their myelin sheaths and supporting oligodendrocytes). This article summarizes this body of literature, examining neuropathological, neurogenetic and neuroradiological evidence for white matter pathology in schizophrenia. We then look at the possible role that antipsychotic medication may play in these studies, examining both its role as a potential confounder in studies examining neuronal density and brain volume, but also the possible role that these medications may play in promoting myelination through their effects on oligodendrocytes. Finally, the role of potential novel therapies is discussed.

Correlations of cerebello-thalamo-prefrontal structure and neurological soft signs in patients with first-episode psychosis

OBJECTIVE

This study aimed at determining brain structural imaging correlates of neurological soft signs (NSS) in patients suffering from a first-episode psychosis.

METHOD

Fifty-two patients with a DSMIV diagnosis of first-episode psychosis (schizophrenia or schizophrenia spectrum disorder) were consecutively included. Subjects were assessed using a standardized neurological examination for motor coordination, motor integration and sensory integration. Anatomical magnetic resonance images (MRI) were analysed in the whole brain using optimized voxel-based morphometry.

RESULTS

Neurological soft signs (NSS) total score (P-corrected = 0.013) and motor integration subscore (P-corrected = 0.035) were found to negatively correlate with grey matter structure of the dorsolateral prefrontal cortices. Motor coordination subscore was positively correlated with grey matter structure of the thalami (P-corrected = 0.002) and negatively with white matter structure of the cerebellum (P-corrected = 0.034). The addition of age and gender as covariate yielded similar results. We did not find any correlation between neither sensory integration subscore and grey matter structure nor NSS total score, motor integration subscore and voxel-based morphometry (VBM) white matter structure.

CONCLUSION

Structural alteration in the cerebello-thalamo-prefrontal network is associated with neurological soft signs in schizophrenia, a candidate network for 'cognitive dysmetria'.

Anterior internal capsule volumes increase in patients with schizophrenia switched from typical antipsychotics to olanzapine

Abnormalities in connectivity are thought to contribute to the symptoms of schizophrenia. Accumulating evidence suggests that antipsychotic medication affects both subcortical and cortical grey and white matter volumes. The goal of this study was to investigate the effects of antipsychotic medication on two white matter tracts: a subcortical-cortical tract, the anterior and posterior limbs of the internal capsule; and a cortical-cortical tract, the corpus callosum. Magnetic resonance imaging was conducted on 10 chronic schizophrenia patients treated with typical antipsychotics and 20 healthy controls at baseline. Patients were switched to olanzapine and both groups were rescanned after 1 year. At baseline, the volume of the anterior limb of the internal capsule was 24% smaller in typical-treated patients than controls (p = 0.009). Patients treated with greater amounts of chlorpromazine-equivalent daily dosage had smaller anterior internal capsule volumes at baseline (r = -0.65, p = 0.04). At follow-up, after being switched to olanzapine, there were no significant differences between patients and controls. Patients with schizophrenia had a significant 25% increase in anterior internal capsule volume from baseline to follow-up compared with controls (p = 0.04). These effects were most prominent in the anterior limb of the internal capsule, which consists of fronto-thalamic pathways, and were not statistically significant in the posterior limb of the internal capsule or corpus callosum. Olanzapine may be effective in normalizing fronto-thalamic structural connectivity in schizophrenia.

Diagnostic yield of computed tomography of the brain in first episode psychosis

INTRODUCTION

Brain computed tomography (CT) is inconsistently recommended worldwide in the investigative algorithm of patients presenting with first episode psychosis (FEP). The objective of this study is to investigate the clinical efficacy of brain CT in patients presenting with FEP without neurological signs in a major metropolitan teaching hospital.

METHODS

The CT brain scan reports of 237 consecutive patients, for which the imaging requests or reports provided a history of FEP but no focal neurological signs, were retrospectively identified within a 6-year period in a 750-bed tertiary referral teaching hospital using the radiology information system text-search function (170 male, 67 female; mean age, 28.3 years). All reports were authored or approved by consultant radiologist. They were reviewed for the presence of any lesion that could cause psychosis and hence alter clinical management. Minor neuroradiological abnormalities were also noted. Hospital Ethics Committee registration and approval were obtained and patient informed consent was not required.

RESULTS

No focal brain lesion potentially responsible for the psychosis or focal lesion requiring surgical intervention was identified in any patient. Findings unable to be directly linked to the psychosis such as evidence of small vessel ischaemic disease, arachnoid cysts, cerebral atrophy, and normal variants were present in 17.6% of patients (45 of 237 studies), none of which led to an alteration of clinical management.

CONCLUSION

The results of this study postulate that brain CT should not be universally performed in the initial assessment of patients with first episode psychosis without neurological signs.

A diffusion tensor imaging study of the anterior limb of the internal capsule in schizophrenia

Frontal-subcortical cognitive and limbic feedback loops modulate higher cognitive functioning. The final step in these feedback loops is the thalamo-cortical projection through the anterior limb of the internal capsule (AL-IC). Using diffusion tensor imaging (DTI), we evaluated abnormalities in the AL-IC fiber tract in schizophrenia. Participants comprised 16 chronic schizophrenia patients and 19 male, normal controls, who were group matched for handedness, age, and parental socioeconomic status, and underwent DTI on a 1.5 Tesla GE system. We measured the diffusion indices, fractional anisotropy (FA), mean diffusivity (MD), radial diffusivity (RD), and axial diffusivity (AD), and manually segmented, based on FA maps, AL-IC volume, normalized for intracranial contents (ICC). The results showed a significant reduction in the ICC-corrected volume of the AL-IC in schizophrenia, but did not show diffusion measure group differences in the AL-IC in FA, MD, RD or AD. In addition, in the schizophrenia patients, AL-IC FA correlated positively with performance on measures of spatial and verbal declarative/episodic memory, and right AL-IC ICC-corrected volume correlated positively with more perseverative responses on the Wisconsin Card Sort Test (WCST). We found a reduction in AL-IC ICC-corrected volume in schizophrenia, without FA, MD, RD or AD group differences, implicating the presence of a structural abnormality in schizophrenia in this subcortical white matter region which contains important cognitive, and limbic feedback pathways that modulate prefrontal cortical function. Despite not demonstrating a group difference in FA, we found that AL-IC FA was a good predictor of spatial and verbal declarative/episodic memory performance in schizophrenia.

Proteome analysis of the thalamus and cerebrospinal fluid reveals glycolysis dysfunction and potential biomarkers candidates for schizophrenia

Schizophrenia (SCZ) is the result of DNA alterations and environmental factors, which together lead to differential protein expression and ultimately to the development of the illness. The diagnosis is based on clinical symptoms, and the molecular background of SCZ is not completely understood. The thalamus, whose dysfunction has been associated with SCZ based in diverse lines of evidences, plays for instance a pivotal role in the central nervous system as a relay center by re-distributing auditory and visual stimuli from diverse brain regions to the cerebral cortex. We analyzed the proteome of postmortem mediodorsal thalamus (MDT) samples from 11 SCZ patients and 8 non-SCZ individuals by using quantitative shotgun-mass spectrometry and two-dimensional gel electrophoresis. Our analyses identified 551 proteins, 50 of which showed significant differential expression. The main pathways affected by the differentially expressed proteins include energy metabolism, oligodendrocyte metabolism, and cytoskeleton assembly. The potential protein biomarkers candidates myelin basic protein and myelin oligodendrocyte protein were validated by Western blot in the MDT samples and also in cerebrospinal fluid from a separate set of samples of 17 first-episode SCZ patients and 10 healthy controls. The differential expression of μ-crystallin, protein kinase C-gamma, and glial fibrillary acidic protein were confirmed in MDT. Because we found several glycolysis enzymes to be differentially expressed, we measured the levels of pyruvate and NADPH and found them to be altered in MDT. The protein changes described here corroborate the importance of myelin/oligodendrocyte and energy metabolism in SCZ and highlight new potential biomarkers candidates that may contribute to the understanding of the pathogenesis of this complex disease.

Updated meta-analyses reveal thalamus volume reduction in patients with first-episode and chronic schizophrenia

OBJECTIVES

Although several structural MRI studies report significant thalamus volume reduction in patients with schizophrenia, many other studies do not. Therefore, the present meta-analyses aimed to clarify whether a reduction in thalamic volume characterizes patients diagnosed with schizophrenia by considering first-episode and chronic phases of the illness and right and left thalamus separately.

METHODS

Using Pubmed databases, we made a detailed literature search for structural MRI studies on patients with schizophrenia that reported physical volumetric measures of the right and left thalamus. Thirteen structural MRI studies were considered eligible for meta-analysis of the entire sample of patients and of the healthy control subjects. Individual meta-analyses were also performed on 6 studies of first-episode patients only and on 7 studies of chronic patients only. These were followed by additional meta-analyses to investigate the role of the factors "illness phase" and "side" on thalamic volume reduction.

RESULTS

Overall, the patient group showed a significant bilateral thalamus volume reduction compared to healthy control subjects. This was found in both first-episode and chronic patients. Furthermore, left thalamus was smaller than right in both patients and healthy control subjects.

CONCLUSIONS

When only studies that used physical volumetric measures were considered, the present meta-analyses confirmed that thalamic volume reduction characterizes patients with schizophrenia, both at the first-episode and chronic phases of the illness.

Anterior thalamic radiation integrity in schizophrenia: a diffusion-tensor imaging study

The anterior limb of the internal capsule (ALIC) is a white matter structure, the medial portion of which includes the anterior thalamic radiation (ATR) carrying nerve fibers between thalamus and prefrontal cortex. ATR abnormalities have a possible link with cognitive abnormalities and negative symptoms in schizophrenia. We aimed to study the fiber integrity of the ATR more selectively by isolating the medial portion of the ALIC using region-of-interest based methodology. Diffusion-tensor imaging was used to measure the anisotropy of total ALIC (tALIC) and medial ALIC (mALIC) in 39 schizophrenia and 33 control participants, matched for age/gender/handedness. Relationships between anisotropy, psychopathology, and cognitive performance were analyzed. Compared with controls, schizophrenia participants had 4.55% lower anisotropy in right tALIC, and 5.38% lower anisotropy in right mALIC. There were no significant group anisotropy differences on the left. Significant correlations were observed between right ALIC integrity and relevant domains of cognitive function (e.g., executive function, working memory). Our study suggests an asymmetric microstructural change in ALIC in schizophrenia involving the right side, which is only minimally stronger in mALIC, and which correlates with cognitive impairment. Microstructural changes in the ALIC may be linked to cognitive dysfunction in schizophrenia.

Opposite roles of dopamine and orexin in quinpirole-induced excessive drinking: a rat model of psychotic polydipsia

RATIONALE

Repeated administration of the dopamine D2/D3 agonist quinpirole (QNP) progressively increases non-regulatory water intake. This effect may model psychotic polydipsia, a potentially fatal but poorly understood condition.

OBJECTIVES

The growing evidence for a role of orexin in mediating arousal and cognition has linked this peptide to schizophrenia, hence we examined whether manipulations of dopaminergic and orexinergic systems, as well as of setting, would further characterize the model.

METHODS

Water intake was measured in rats sequentially tested in home and then operant conditioning setting, with chronic administration of D2 antagonist haloperidol (Hal) prior to QNP treatment. A group of rats similarly treated was also assessed for orexin A (OxA) expression in the cortex. Finally, the effect of the orexin-1 receptor antagonist SB-334867 on QNP-induced polydipsia was evaluated.

RESULTS

In rats made polydipsic by QNP the amount of water drank during the first 4 h was strongly correlated with the degree of dissociation between appetitive and consummatory components of drinking behavior in the following hour of operant access to water. Hal 0.2 mg/kg prevented both polydipsia and the dissociation, while 0.1 mg/kg only blocked the dissociation. Chronic QNP treatment increased, in a Hal-reversible way, OxA expression in the somatosensory cortex (SI). Moreover, pretreatment with SB-334867 sped up and potentiated QNP-induced polydipsia.

CONCLUSIONS

Results disclose compulsive components in QNP-induced polydipsia that are mediated by dopamine D2 receptors. QNP also regulates OxA expression in the SI, while the block of orexin-1 receptors enhances QNP-induced polydipsia. We suggest that dopamine and OxA play opposite roles in QNP-induced polydipsia.

Thalamic nuclear abnormalities as a contributory factor in sudden cardiac deaths among patients with schizophrenia

Patients with schizophrenia have a two- to three-fold increased risk of premature death as compared to patients without this disease. It has been established that patients with schizophrenia are at a high risk of developing cardiovascular disease. Moreover, an important issue that has not yet been explored is a possible existence of a "cerebral" focus that could trigger sudden cardiac death in patients with schizophrenia. Along these lines, several structural and functional alterations in the thalamic complex are evident in patients with schizophrenia and have been correlated with the symptoms manifested by these patients. With regard to abnormalities on the cellular and molecular level, previous studies have shown that schizophrenic patients have fewer neuronal projections from the thalamus to the prefrontal cortex as well as a reduced number of neurons, a reduced volume of either the entire thalamus or its subnuclei, and abnormal glutamate signaling. According to the glutamate hypothesis of schizophrenia, hypofunctional corticostriatal and striatothalamic projections are directly involved in the pathophysiology of the disease. Animal and post-mortem studies have provided a large amount of evidence that links the sudden unexpected death in epilepsy (SUDEP) that occurs in patients with schizophrenia and epilepsy to thalamic changes. Based on the results of these prior studies, it is clear that further research regarding the relationship between the thalamus and sudden cardiac death is of vital importance.

Modeling "psychosis" in vitro by inducing disordered neuronal network activity in cortical brain slices

INTRODUCTION

Dysregulation of neuronal networks has been suggested to underlie the cognitive and perceptual abnormalities observed schizophrenia.

DISCUSSIONS

An in vitro model of psychosis is proposed based on the two different approaches to cause aberrant network activity in layer V pyramidal cells of prefrontal brain slices: (1) psychedelic hallucinogens such as lysergic acid diethylamide and (2) minimal GABA(A) receptor antagonism, modeling the GABA interneuron deficit in schizophrenia. A test of this model would be to determine if drugs that normalize aberrant networks in brain slices have efficacy in the treatment of schizophrenia. Selective agonists of glutamate mGlu2/3 metabotropic receptors, which are highly effective in suppressing aberrant network activity in slices, are the most advanced toward reaching that clinical endpoint. In accord with the model, a recent phase II clinical trial shows that an mGlu2/3 receptor agonist is equivalent in efficacy to a standard antipsychotic drug for both negative and positive symptoms in schizophrenic patients, but without the usual side effects. D1/5 dopamine receptor agonists are also effective in normalizing aberrant network activity induced by both hallucinogens and minimal GABA(A) antagonism; clinical efficacy remains to be determined. A general model of network regulation is presented, involving astrocytes, GABA interneurons, and glutamatergic pyramidal cells, revealing a wide range of potential sites hitherto not considered as therapeutic targets.

Omega-3 consumption and sudden cardiac death in schizophrenia

People with schizophrenia show a two- to three-fold increased risk to die prematurely. Mortality is accounted for by a combination of factors (patients' life style, suicide, premature cardiovascular disease, metabolic syndromes and, not so often mentioned, sudden death). The cause of sudden death in schizophrenia is unknown, but cardiac arrhythmia plays a potential role. Patients with schizophrenia are at high risk for cardiovascular disease, and some antipsychotics may be associated with cardiovascular adverse events (e.g., electrocardiograph QT interval prolongation), suggesting that this could lead to sudden cardiac death. Animal and clinical studies have shown that omega-3 fatty acids could be useful in the prevention and treatment of schizophrenia. As omega-3 fatty acids have been considered a cardioprotector agent, reducing cardiac arrhythmias and hence sudden cardiac deaths and given their relative safety and general health benefits, our update article summarizes the knowledge by the possible positive effects of omega-3 supplementation and fish consumption against sudden cardiac death in patients with schizophrenia. However, fish species should be selected with caution due to contamination with toxic methylmercury.

Internal capsule size associated with outcome in first-episode schizophrenia

Subtle structural brain abnormalities are an established finding in first-episode psychosis. Nevertheless their relationship to the clinical course of schizophrenia is controversially discussed. In a multicentre study 45 first-episode schizophrenia patients (FE-SZ) underwent standardized MRI scanning and were followed up to 1 year. In 32 FE-SZ volumetric measurement of three regions of interests (ROIs) potentially associated with disease course, hippocampus, lateral ventricle and the anterior limb of the internal capsule (ALIC) could be performed. The subgroups of FE-SZ with good (12 patients) and poor outcome (11 patients), defined by a clinically relevant change of the PANSS score, were compared with regard to these volumetric measures. Multivariate analysis of covariance revealed a significant reduced maximal cross sectional area of the left ALIC in FE-SZ with clinically relevant deterioration compared to those with stable psychopathology. There were no differences in the other selected ROIs between the two subgroups. In conclusion, reduced maximal area of ALIC, which can be interpreted as a disturbance of fronto-thalamic connectivity, is associated with poor outcome during the 1 year course of first-episode schizophrenia.

Metabolic abnormalities in fronto-striatal-thalamic white matter tracts in schizophrenia

The anterior limb of the internal capsule (ALIC) is the major white matter tract providing reciprocal connections between the frontal cortex, striatum and thalamus. Mounting evidence suggests that this tract may be affected in schizophrenia, with brain imaging studies reporting reductions in white matter volume and density, changes in fractional anisotropy and reduced asymmetry. However, the molecular correlates of these deficits are currently unknown. The aim of this study was to identify alterations in protein and metabolite levels in the ALIC in schizophrenia. Samples were obtained post-mortem from individuals with schizophrenia (n=15) and non-psychiatric controls (n=13). Immunoreactivity for the myelin-associated protein myelin basic protein (MBP), and the axonal-associated proteins phosphorylated neurofilament and SNAP-25 was measured by enzyme-linked immunoadsorbent assay (ELISA). Metabolite concentrations were quantified by proton nuclear magnetic resonance ((1)H NMR) spectroscopy. Levels of myelin- or axonal-associated proteins did not differ between groups. Overall differences in metabolite concentrations were observed between the two groups (MANOVA F=2.685, p=0.036), with post-hoc tests revealing lower lactate (19%) and alanine (24%) levels in the schizophrenia group relative to controls. Observed changes in lactate and alanine levels indicate metabolic abnormalities within the ALIC in schizophrenia.

Volumetric and shape analysis of the thalamus in first-episode schizophrenia

Thalamic abnormalities have been implicated in the pathogenesis of schizophrenia, although the majority of studies used chronic samples treated extensively with antipsychotics. Moreover, the clinical and neuropsychological correlates of these abnormalities remain largely unknown. Using high-resolution MR imaging and novel methods for shape analysis, we investigated thalamic subregions in 35 (25 M/10 F) first-episode schizophrenia patients compared with 33 (23 M/10 F) healthy volunteers. The right and left thalami were traced bilaterally on coronal brain slices and volumes were compared between groups. In addition, regional abnormalities were identified by comparing distances, measured from homologous thalamic surface points to the central core of each individual's surface model, between groups in 3D space. Patients had significantly less total thalamic volume compared with healthy volunteers. Statistical mapping demonstrated most pronounced shape abnormalities in the pulvinar; however, estimated false discovery rates in these regions were sizable. Smaller thalamus volume was significantly correlated with worse overall neuropsychological functioning and specific deficits were observed in the language, motor, and executive domains. There were no significant associations between thalamus volume and positive or negative symptoms. Our findings suggest that thalamic abnormalities are evident at the onset of a first episode of schizophrenia prior to extensive pharmacologic intervention and that these abnormalities have neuropsychological correlates.

The thalamus and schizophrenia: current status of research

The thalamus provides a nodal link for multiple functional circuits that are impaired in schizophrenia (SZ). Despite inconsistencies in the literature, a meta analysis suggests that the volume of the thalamus relative to that of the brain is decreased in SZ. Morphometric neuroimaging studies employing deformation, voxel-based and region of interest methodologies suggest that the volume deficit preferentially affects the thalamic regions containing the anterior and mediodorsal nuclei, and the pulvinar. Postmortem design-based stereological studies have produced mixed results regarding volume and neuronal deficits in these nuclei. This review examines those aspects of thalamic circuitry and function that suggest salience to SZ. Evidence for anomalies of thalamic structure and function obtained from postmortem and neuroimaging studies is then examined and directions for further research proposed.

The anatomy of first-episode and chronic schizophrenia: an anatomical likelihood estimation meta-analysis

OBJECTIVE

The authors sought to map gray matter changes in first-episode schizophrenia and to compare these with the changes in chronic schizophrenia. They postulated that the data would show a progression of changes from hippocampal deficits in first-episode schizophrenia to include volume reductions in the amygdala and cortical gray matter in chronic schizophrenia.

METHOD

A systematic search was conducted for voxel-based structural MRI studies of patients with first-episode schizophrenia and chronic schizophrenia in relation to comparison groups. Meta-analyses of the coordinates of gray matter differences were carried out using anatomical likelihood estimation. Maps of gray matter changes were constructed, and subtraction meta-analysis was used to compare them.

RESULTS

A total of 27 articles were identified for inclusion in the meta-analyses. A marked correspondence was observed in regions affected by both first-episode schizophrenia and chronic schizophrenia, including gray matter decreases in the thalamus, the left uncus/amygdala region, the insula bilaterally, and the anterior cingulate. In the comparison of first-episode schizophrenia and chronic schizophrenia, decreases in gray matter volume were detected in first-episode schizophrenia but not in chronic schizophrenia in the caudate head bilaterally; decreases were more widespread in cortical regions in chronic schizophrenia.

CONCLUSIONS

Anatomical changes in first-episode schizophrenia broadly coincide with a basal ganglia-thalamocortical circuit. These changes include bilateral reductions in caudate head gray matter, which are absent in chronic schizophrenia. Comparing first-episode schizophrenia and chronic schizophrenia, the authors did not find evidence for the temporolimbic progression of pathology from hippocampus to amygdala, but there was evidence for progression of cortical changes.

Schizophrenia, hypocretin (orexin), and the thalamocortical activating system

Diminished connectivity between midline-intralaminar thalamic nuclei and prefrontal cortex has been suggested to contribute to cognitive deficits that are detectable even in early stages of schizophrenia. The midline-intralaminar relay cells comprise the final link in the ascending arousal pathway and are selectively excited by the wake-promoting peptides hypocretin 1 and 2 (orexin A and B). This excitation occurs both at the level of the relay cell bodies and their axon terminals within prefrontal cortex. In rat brain slices, the release of glutamate from midline-intralaminar thalamocortical terminals induces excitatory postsynaptic currents (EPSCs) in layer V pyramidal cells in prefrontal cortex. When hypocretin is infused into medial prefrontal cortex of behaving animals, it improves performance in a complex cognitive task requiring divided attention. Chronic restraint stress causes atrophy of the apical dendritic arbors in layer V prefrontal pyramidal cells and leads to a reduction in hypocretin-induced EPSCs, indicating impairment in excitatory thalamocortical transmission. Thus, taken together with evidence for an underlying loss of excitatory thalamocortical connectivity in schizophrenia, stress in this illness could further exacerbate a breakdown in cortical processing of incoming information from the ascending arousal system.

Cerebral Disconnectivity: An Early Event in Schizophrenia

Neuroimaging and electrophysiological investigations have demonstrated numerous differences in brain morphology and function of chronic schizophrenia patients compared to healthy controls. Studying patients at the beginning of their disease without the confounding effects of chronicity, medication, and institutionalization may provide a better understanding of schizophrenia. Recently, at many institutions around the world, special projects have been launched for specialized treatment and research of this interesting patient group. Using the PubMed search engine in this update, the authors summarize recent investigations between January 2002 and September 2006 that focus on whether signs of disconnectivity already exist early in the disease process. They discuss gray and white matter changes, their impact on symptomatology, electroencephalogram-based studies on connectivity, and possible influences of medication. NEUROSCIENTIST 14(1):19—45, 2008. DOI: 10.1177/1073858406298391

A neuropsychiatry service in a state hospital. Adolf Meyer's approach revisited

In the spirit of Adolf Mayer's medico-biological approach to the understanding of mental illnesses the article describes the advantages that neuropsychiatric approach brings to the diagnostic evaluation and treatment of psychiatric patients in a state hospital. Our review discusses the neuropsychiatric approach to the evaluation of state hospital patients with mild, moderate, and severe cognitive disturbances showing the role of neuropsychological testing, electroencephalography (EEG), and brain imaging in the neuropsychiatric assessment of primary and secondary mental illnesses. Neuropsychiatric evaluation helps to assess the peculiarities of movement disorder as a of side effects of regular psychiatric medications, e.g. the differences in diagnostic signs and treatment implication between Parkinson's disease and extrapyramidal syndrome (EPS) as a side effect of neuroleptics as well as the development of abnormal reflexes as a sign of tardive dyskinesia (TD) not directly related to the lesion of upper motor neuron. The article also discusses the development of hypokinetic delirium in the course of treatment of psychiatric patients not only as a side effect of neuroleptics but also of anticonvulsants, increasingly used as the mood stabilizers in modern psychiatry. Since aggressive behavior of psychiatric patients represents one of the major criteria for admission and often long term treatment in a state hospital, special consideration is given to the role of brain paroxysmal activity in the development of aggressive behavior, especially rage attacks, one of the main manifestations of aggressive behavior in a state hospital patients. Correspondingly, the use of anticonvulsants in the treatment of rage attacks is discussed. This article may serve as a model for the use of neuropsychiatric service in improvement of diagnostic evaluation and treatment of psychiatric patients in a state hospital.

A longitudinal study on the effects of typical versus atypical antipsychotic drugs on hippocampal volume in schizophrenia

BACKGROUND

Previous studies have reported that hippocampal volumes correlate with symptom severity in schizophrenia. This longitudinal study measured changes in symptoms and hippocampal volume in patients switched from typical antipsychotics to olanzapine.

METHODS

MRI scans were acquired from patients with chronic schizophrenia (n=10) and healthy volunteers (n=20). At baseline, patients were treated with typical antipsychotics for at least one year, then switched to olanzapine, and rescanned approximately one year later.

RESULTS

Olanzapine treatment resulted in no significant change in right or left hippocampal volume. Individual changes in right hippocampal volume correlated significantly with changes in symptoms.

CONCLUSIONS

Hippocampal volume change may serve as a marker of symptom change in patients on olanzapine.

Internal capsule, corpus callosum and long associative fibers in good and poor outcome schizophrenia: a diffusion tensor imaging survey

BACKGROUND

Prior voxelwise studies of white matter anisotropy found widespread reductions involving all major fiber tracts of the schizophrenic brain. We set out to confirm these exploratory findings and evaluate their relation to illness severity using a hypothesis-driven region-of-interest approach.

METHODS

104 schizophrenia patients (51 with good outcomes, 53 with poor outcomes) and 41 matched comparison subjects participated in the study. Regions of interest were selected on the basis of published voxelwise findings and placed within major fiber tracts using Talairach's stereotaxic coordinates.

RESULTS

Fractional anisotropy reductions in schizophrenia patients were confirmed in the left cingulum, anterior thalamic radiation, fronto-occipital and inferior longitudinal fasciculi, as well as bilaterally in the corpus callosum, anterior and posterior limbs of internal capsule, superior longitudinal fasciculus, optic radiation, and frontotemporal extrafascicular white matter. Anisotropy reductions were more extensive in patients with poor outcomes ("Kraepelinian"), particularly in the posterior corpus callosum, fronto-occipital fasciculus, left optic radiation and frontotemporal white matter. Lower anisotropy in the right hemisphere tracts was associated with more prominent positive symptomatology, whereas negative symptoms were inversely associated with anisotropy values in both hemispheres.

CONCLUSIONS

These results support a global neural disconnectivity in schizophrenia patients, which is more severe in those with poor clinical outcomes.

Reduced thalamic volume in first-episode non-affective psychosis: correlations with clinical variables, symptomatology and cognitive functioning

Structural studies have inconsistently shown the presence of thalamic volume differences in patients with schizophrenia. However, only a few studies have examined the relation between thalamic structure and clinical and cognitive variables in early phases of the illness. Thalamic volumes in right-handed minimally treated first episode patients with non-affective psychosis (N=61) relative to those of right-handed healthy comparison subjects (N=40) were measured. Thalamic volumes in the right and left hemispheres and total thalamic volume were automatically segmented and analyzed using BRAINS2. Analysis of covariance was used to control for intracranial volume. Clinical symptoms were assessed by total scores of BPRS, SAPS and SANS. The relationship between three cognitive dimensions (verbal learning and memory, speed processing/executive functioning and sustained attention/vigilance), and thalamic volume was evaluated. The impact of the duration of untreated illness, untreated psychosis and prodrome period in thalamic morphometry was also explored. Right, left, and total thalamic volumes of the patients with non-affective psychosis were significantly smaller than those of the healthy subjects. Larger thalamic volumes were associated with an earlier age of onset, a poorer cognitive functioning and a more severe negative symptomatology. Thalamic volumetric differences between patients with non-affective psychosis and healthy controls are already present at early phases of the illness. However, further investigations are warranted to fully clarify the relationship between those structural anomalies and clinical and cognitive outcomes.

Diffusion tensor imaging of frontal lobe white matter tracts in schizophrenia

We acquired diffusion tensor and structural MRI images on 103 patients with schizophrenia and 41 age-matched normal controls. The vector data was used to trace tracts from a region of interest in the anterior limb of the internal capsule to the prefrontal cortex. Patients with schizophrenia had tract paths that were significantly shorter in length from the center of internal capsule to prefrontal white matter. These tracts, the anterior thalamic radiations, are important in frontal-striatal-thalamic pathways. These results are consistent with findings of smaller size of the anterior limb of the internal capsule in patients with schizophrenia, diffusion tensor anisotropy decreases in frontal white matter in schizophrenia and hypothesized disruption of the frontal-striatal-thalamic pathway system.