Schizophrenia as a chronic active brain process: a study of progressive brain structural change subsequent to the onset of schizophrenia

Automatic identification of schizophrenia employing EEG records analyzed with deep learning algorithms

Electroencephalography is a method of detecting and analyzing electrical activity in the brain. This electrical activity can be recorded and processed to aid in the clinical diagnosis of mental disorders. In this study, a novel system for classifying schizophrenia patients from EEG recordings is presented. The developed algorithm decomposes the EEG signals into a system of radial basis functions using the method of fuzzy means. This decomposition helps to obtain the information from the various electrodes of the EEG and allows separating between healthy controls and patients with schizophrenia. The proposed method has been compared with classical machine learning algorithms, such as, K-Nearest Neighbor, Adaboost, Support Vector Machine, and Bayesian Linear Discriminant Analysis. The results show that the proposed method obtains the highest values in terms of balanced accuracy, recall, precision and F1 score, close to 93 % in all cases. The model developed in this study can be implemented in brain activity analysis systems that help in the prediction of patients with schizophrenia.

Dementia among older people with schizophrenia: an update on recent studies

PURPOSE OF REVIEW

This narrative review examines recently published research that examines the prevalence, underlying causes, and treatments for dementia among people with schizophrenia.

RECENT FINDINGS

People with schizophrenia have high rates of dementia, compared with the general population, and cognitive decline has been observed 14 years prior to onset of psychosis with accelerated decline in middle age. Underlying mechanisms of cognitive decline in schizophrenia include low cognitive reserve, accelerated cognitive aging, cerebrovascular disease and medication exposure. Although pharmacologic, psychosocial and lifestyle interventions show early promise for preventing and mitigating cognitive decline, few studies have been conducted in older people with schizophrenia.

SUMMARY

Recent evidence supports accelerated cognitive decline and brain changes in middle-aged and older people with schizophrenia, relative to the general population. More research in older people with schizophrenia is needed to tailor existing cognitive interventions and develop novel approaches for this vulnerable and high-risk group.

A systematic review of multimodal brain age studies: Uncovering a divergence between model accuracy and utility

Brain aging is a complex, multifaceted process that can be challenging to model in ways that are accurate and clinically useful. One of the most common approaches has been to apply machine learning to neuroimaging data with the goal of predicting age in a data-driven manner. Building on initial brain age studies that were derived solely from T1-weighted scans (i.e., unimodal), recent studies have incorporated features across multiple imaging modalities (i.e., "multimodal"). In this systematic review, we show that unimodal and multimodal models have distinct advantages. Multimodal models are the most accurate and sensitive to differences in chronic brain disorders. In contrast, unimodal models from functional magnetic resonance imaging were most sensitive to differences across a broad array of phenotypes. Altogether, multimodal imaging has provided us valuable insight for improving the accuracy of brain age models, but there is still much untapped potential with regard to achieving widespread clinical utility.

Factors Contributing to Risk of Persistence of Positive and Negative Symptoms in Schizophrenia during Hospitalization

The aim of the study was to evaluate factors that may contribute to the persistence of positive, negative and other psychopathological symptoms of schizophrenia. All patients were treated in general psychiatric wards between January 2006 and December 2017. The initial study sample comprised of the medical reports of 600 patients. The main, specified inclusion criterion for the study was schizophrenia as a discharge diagnosis. Medical reports of 262 patients were excluded from the study due to no neuroimaging scans being available. The symptoms were categorised into three groups: positive, negative, and other psychopathological symptoms. The statistical analysis comprised modalities such as demographic data, clinical symptoms, as well as neuroimaging scans linking them to a potential impact of sustaining the mentioned groups of symptoms during the period of hospitalization. The analysis revealed that statistically significant risk factors of persistence of the three groups of symptoms are the elderly age, the increasing toll of hospitalizations, suicidal attempts in medical history, a family history of alcohol abuse, the presence of positive, negative and other psychopathological symptoms on admission to the hospital, as well as the absence of cavum septi pellucidi (CSP). The study showed that addiction to psychotropic drugs and a family history of schizophrenia were more frequent in patients with persistent CSP.

Functional connectivity and gray matter deficits within the auditory attention circuit in first-episode psychosis

Background

Selective attention deficits in first episode of psychosis (FEP) can be indexed by impaired attentional modulation of auditory M100. It is unknown if the pathophysiology underlying this deficit is restricted to auditory cortex or involves a distributed attention network. We examined the auditory attention network in FEP.

Methods

MEG was recorded from 27 FEP and 31 matched healthy controls (HC) while alternately ignoring or attending tones. A whole-brain analysis of MEG source activity during auditory M100 identified non-auditory areas with increased activity. Time-frequency activity and phase-amplitude coupling were examined in auditory cortex to identify the attentional executive carrier frequency. Attention networks were defined by phase-locking at the carrier frequency. Spectral and gray matter deficits in the identified circuits were examined in FEP.

Results

Attention-related activity was identified in prefrontal and parietal regions, markedly in precuneus. Theta power and phase coupling to gamma amplitude increased with attention in left primary auditory cortex. Two unilateral attention networks were identified with precuneus seeds in HC. Network synchrony was impaired in FEP. Gray matter thickness was reduced within the left hemisphere network in FEP but did not correlate with synchrony.

Conclusion

Several extra-auditory attention areas with attention-related activity were identified. Theta was the carrier frequency for attentional modulation in auditory cortex. Left and right hemisphere attention networks were identified, with bilateral functional deficits and left hemisphere structural deficits, though FEP showed intact auditory cortex theta phase-gamma amplitude coupling. These novel findings indicate attention-related circuitopathy early in psychosis potentially amenable to future non-invasive interventions.

Brain plasticity, language anomalies, genetic risk and the patient with schizophrenia: Trajectory of change over a lifetime. A commentary

Research on schizophrenia has been pursued for over a century. While the ability to view the brain and also the entire human genome advanced dramatically during this time and particularly in recent years, it is still unclear whether these advances helped to understand the nature of schizophrenia. What appears, however, to be the case is that early detection and treatment of people who are at high risk for developing schizophrenia due to various clinical signs, lead to better outcomes and recovery in many cases. Medications have also dramatically improved and have not been associated with the side-effects of earlier treatments, although they still are not without new sets of adverse effects. Over the years it was shown that structural brain abnormalities were present in the brains of people with chronic schizophrenia and that these observations were present early in the onset of illness. It was then shown these were not static and changed over the years of illness. At the same time it was shown that the brain centers for perceiving and speaking language appeared particularly abnormal in patients with schizophrenia and that these abnormalities could underlie the misperceptions and experiences of auditory hallucinations so characteristic of this illness. In a separate set of investigations that began with family, then twin and adoption studies, it was shown that schizophrenia is inherited, but in a complex manner. At present many genetic studies now find that genes, whose variants can lead to a high risk for schizophrenia, are ones specifically involving brain development and functioning. At present, although still speculative, it can be concluded that the progressive changes in brain structure, particularly related to language processing, take place in genetically vulnerable people and put them ultimately at high risk for developing schizophrenia in a trajectory for a lifelong illness. It is hoped that in the future these brain changes can be prevented by intervening early on the processes of brain growth and plasticity, thus arresting the illness before it begins.

Correlation between duration of untreated psychosis and long-term prognosis in chronic schizophrenia

OBJECTIVE

To explore the relationship between the Duration of Untreated Psychosis (DUP) and long-term clinical outcome, cognitive and social function in patients with chronic schizophrenia (SCZ).

METHODS

A total of 248 subjects with chronic SCZ were enrolled in this study, including 156 in the short DUP group and 92 in the long DUP group. The Positive and Negative Symptoms Scale (PANSS), the Brief Negative Symptoms Scale (BNSS), the Global Assessment of Functioning (GAF) scale and the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) were used to assess all of the subjects.

RESULTS

The negative symptom scores (the PANSS and BNSS) of subjects with long DUP were significantly higher than that in subjects with short DUP. The scores of visual span and speech function in the short DUP group were significantly higher, indicative of decreasing cognitive function with time. In terms of social function, the short DUP group scored higher, with a statistically significant difference. Meanwhile, we found that the length of DUP was positively correlated with the negative symptom score of the PANSS, negatively correlated with visual span scores, and GAF scores.

CONCLUSION

This study demonstrated that the DUP remained a significant association with negative symptom and cognition in long period of chronic SCZ.

Cognitive trajectories following onset of psychosis: a meta-analysis

BACKGROUND

Cognitive impairment is a core feature of schizophrenia, associated with poor functional outcomes. The course of cognitive function in the years following illness onset has remained a subject of debate, with a previous analysis finding no worsening, providing support for the neurodevelopmental model of schizophrenia. Since then, many more studies have reported on longitudinal cognitive performance in early psychosis, with some indicating deterioration, which does not align with this view.

AIMS

This study aims to quantitatively review the literature on the longitudinal trajectory of cognitive deficits in the years following psychosis onset, in comparison with healthy controls. It is the first to also synthesise longitudinal data on social cognition.

METHOD

Electronic databases ('PubMed', 'PsycInfo' and 'Scopus') were searched (to end September 2021). Meta-analyses of 25 longitudinal studies of cognition in early psychosis were conducted (1480 patients, 789 health controls). Unlike previous analyses, randomised controlled trials and those with multiple cognitive testing periods within the first year were excluded to minimise bias (PROSPERO, ID: CRD42021241525).

RESULTS

Small improvements were observed for global cognition (g = 0.25, 95% CI 0.17-0.33) and individual cognitive domains, but these were comparable with healthy controls and likely an artefact of practice effects.

CONCLUSIONS

There is no evidence of continued cognitive decline or improvement in the early years following psychosis onset, with a need for more studies over longer follow-up periods. Practice effects highlight the importance of including control samples in longitudinal and intervention studies. Further data are needed to evaluate the course of social cognition subdomains.

Dynamic and Static Cognitive Deficits in Schizophrenia and Bipolar Disorder After the First Episode

Few studies have comprehensively examined the profile of cognitive functioning in first episode psychosis patients throughout the lifespan, and from first episode to chronic stage. We assessed functioning in general and specific cognitive functions, comparing both schizophrenia (N = 64) and bipolar I (N = 19) patients to controls (N = 103). Participants were from a population-based, case-control study of first episode psychosis patients, who were followed prospectively up to 10 years post first admission. A cognitive battery was administered at baseline and follow-up. By combining longitudinal and cross-sectional data, we were able to examine the cognitive profile of patients and controls throughout the entire age range of our sample (16-65). Schizophrenia patients exhibited widespread declines in IQ, executive function, visual memory, language ability, and verbal knowledge. However, the ages at which these declines occurred differed between functions. Deficits in verbal memory, working memory, processing speed, and visuospatial ability, on the other hand, were present at the first episode, and remained relatively static thereafter. Bipolar I patients also showed declines in IQ, verbal knowledge, and language ability, albeit at different ages to schizophrenia patients and only in verbal functions. Deficits on measures of verbal memory, processing speed, and executive function remained relatively static. Thus, both schizophrenia and bipolar I patients experienced cognitive decline in general and specific functions after the first episode, but the age at which these declines occurred differed between disorder and function. Cognitive remediation efforts may be most fruitful when targeting individual functions during specific time periods throughout adulthood.

Neurodegenerative model of schizophrenia: Growing evidence to support a revisit

Multidimensional progressive declines in the absence of standard biomarkers for neurodegeneration are observed commonly in the development of schizophrenia, and are accepted as consistent with neurodevelopmental etiological hypotheses to explain the origins of the disorder. Far less accepted is the possibility that neurodegenerative processes are involved as well, or even that key dimensions of function, such as cognition and aspects of biological integrity, such as white matter function, decline in chronic schizophrenia beyond levels associated with normal aging. We propose that recent research germane to these issues warrants a current look at the question of neurodegeneration. We propose the view that a neurodegenerative hypothesis provides a better explanation of some features of chronic schizophrenia, including accelerated aging, than is provided by neurodevelopmental hypotheses. Moreover, we suggest that neurodevelopmental influences in early life, including those that may extend to later life, do not preclude the development of neurodegenerative processes in later life, including some declines in cognitive and biological integrity. We evaluate these views by integrating recent findings in representative domains such as cognition and white and gray matter integrity with results from studies on accelerated aging, together with functional implications of neurodegeneration for our understanding of chronic schizophrenia.

A systematic review of the neural correlates of multisensory integration in schizophrenia

Multisensory integration (MSI), in which sensory signals from different modalities are unified, is necessary for our comprehensive perception of and effective adaptation to the objects and events around us. However, individuals with schizophrenia suffer from impairments in MSI, which could explain typical symptoms like hallucination and reality distortion. Because the neural correlates of aberrant MSI in schizophrenia help us understand the physiognomy of this psychiatric disorder, we performed a systematic review of the current research on this subject. The literature search concerned investigated MSI in diagnosed schizophrenia patients compared to healthy controls using brain imaging. Seventeen of 317 identified studies were finally included. To assess risk of bias, the Newcastle-Ottawa quality assessment was used, and the review was written according to the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA). The results indicated that multisensory processes in schizophrenia are associated with aberrant, mainly reduced, neural activity in several brain regions, as measured by event-related potentials, oscillations, activity and connectivity. The conclusion is that a fronto-temporal region, comprising the frontal inferior gyrus, middle temporal gyrus and superior temporal gyrus/sulcus, along with the fusiform gyrus and dorsal visual stream in the occipital-parietal lobe are possible key regions of deficient MSI in schizophrenia.

Mental Illness and Amyloid: A Scoping Review of Scientific Evidence over the Last 10 Years (2011 to 2021)

Amyloid precursor protein and its derivates represent a central factor in the process of neurodegeneration in Alzheimer’s disease (AD). Since mental illnesses share with AD cognitive impairment, amyloid indicators have been used to explore the unknown pathophysiologic mechanisms underlining psychiatric illness. This work aims to compare the role of amyloid markers, together with tau proteins, among various mental disorders evaluating the possible role of altered amyloid metabolism in the onset and in the course of psychiatric diseases, considering the relationship with cognitive impairment in dementia. This review includes articles written in English, published between 1 January 2011 and 31 January 2021, which evaluated amyloid and tau proteins in psychiatric patients. After screening, 31 studies were included in the review. Results suggest that amyloid metabolism is altered in major psychiatric disorders and that it could be a marker of cognitive impairment. Nevertheless, the role of amyloid in mental diseases seems to be related to neurodevelopmental alteration as well as neurodegeneration processes, like in AD. The role of amyloid in the pathogenesis of mental disorders is still unknown. Amyloid should not be only considered as a marker of cognitive impairment in mental illness, but also for altered neurodevelopment.

Magnetic resonance imaging of brain anomalies in adult and pediatric schizophrenia patients: Experience of a Romanian tertiary hospital

Schizophrenia is a severe mental illness with a significant impact on the life of both the patient and the patient's family. Magnetic resonance imaging has proven a useful tool for studying structural changes of the brain in schizophrenia. However, interpreting the published literature presents several challenges. Despite thorough research in recent years, which has included anatomopathological, imaging, electrophysiological, and genetic studies, the intimate pathophysiological mechanisms of this disease are not yet fully elucidated. The present study included patients with schizophrenia diagnosed in the psychiatric clinics from the ‘Prof. Dr. Alexandru Obregia’ Clinical Psychiatry Hospital between September 2019 and December 2020. Three Tesla magnetic resonance neuroimaging studies were performed. In a significant number of cases, the neuroimaging studies showed association of cerebral modifications such as enlargement of the Virchow spaces, lesions of the white matter with demyelinating appearance, and inflammatory sinus reactions. Cortical atrophy and hemosiderotic spots were present in a statistically significant proportion in the patient group with an age range of 29-61 years. MRI is indicated as a useful technique in the follow-up process of schizophrenia patients. However, whether the anomalies revealed in this disorder can be utilised as diagnostic biomarkers is still being debated.

Analysis of the superior temporal gyrus as a possible biomarker in schizophrenia using voxel-based morphometry of the brain magnetic resonance imaging: a comprehensive review

The lack of predictive biomarkers for therapeutic responses to schizophrenia leads clinical procedures to be decided without taking into account the subjects' neuroanatomical features, a consideration, which could help in identifying specific pharmacological treatments for the remission of symptoms. Magnetic resonance imaging (MRI) is a technique widely used for radiological diagnosis and produces 3-dimensional images in excellent anatomical detail, and with a great capacity to differentiate soft tissue. Various MRI techniques of the human brain have emerged as a result of research, enabling structural tests that may help to in consolidate previous findings and lead to the discovery of new patterns of abnormality in schizophrenia. A literature review was undertaken to assess the superior temporal gyrus (STG) as a possible biomarker in schizophrenia with the use of voxel-based morphometry of the brain using MRI. Many findings in studies of schizophrenia using MRI have been inconclusive and, in some cases, conflicting, although interesting results have been obtained when attempting to correlate neuroimaging changes with aspects of clinical features and prognosis of the disease. The individuals affected by this mental illness appear to have smaller STG volumes when compared to healthy controls and also to subjects with a diagnosis of first-episode affective psychosis or groups of individuals at high risk of psychosis. However, the wide variety of definitions surrounding the STG found in a number of studies is a contributing factor to the lack of correlation between brain abnormalities and clinical symptoms. For instance, disagreements have arisen due to studies using regions of interest to analyze the STG whereas other studies prioritize the analysis of only STG subregions or specific supratemporal plane regions. It is necessary to standardize the nomenclature of the areas to be studied in the future, as this will enable more consistent results, allowing higher clinical and morphological correlations.

Strucutural brain imaging at the onset of schizophrenia:What have we learned and what have we missed

Over the past 50 years, the application of structural neuroimaging techniques to schizophrenia research has added relevant information about the pathophysiology of the disorder. Several lines of investigation gave strong evidence that schizophrenia is associated with multiple subtle brain abnormalities that involve both cerebral grey and white matter volumes and structure. The time of onset and longitudinal course of brain morphological abnormalities support the notion that brain pathology of schizophrenia has a neurodevelopmental component and a progressive course, although several confounders of brain changes should be carefully taken into account. Brain anomalies detected before and close to the onset of schizophrenia are likely to be unrelated to confounders of brain changes such as antipsychotic drug treatment, duration of illness or illicit substance abuse, i.e. they related to the pathological process of the disorder per se. Nonetheless, clinically useful diagnostic or prognostic biomarkers have not derived from neuroimaging studies and this is likely related to the neurobiological heterogeneity of the disorder. Thus, there is the compelling need to set new methodological standards for developing innovative hypothesis-driven studies to overcome what we have missed to date in neuroimaging research in schizophrenia.

Magnetic resonance imaging in schizophrenia: Luxury or necessity? (Review)

Schizophrenia, one of the most common psychiatric disorders, with a worldwide annual incidence rate of approximately 0.3-0.7%, known to affect the population below 25 years of age, is persistent throughout lifetime and includes people from all layers of society. With recent technological progress that allows better imaging techniques, such as the ones provided by computed tomography and particularly magnetic resonance imaging (MRI), research on schizophrenia imaging has grown considerably. The purpose of this review is to establish the importance of using imaging techniques in the early detection of brain abnormalities in patients diagnosed with schizophrenia. We reviewed all articles which reported on MRI imaging in schizophrenia. In order to do this, we used the PubMed database, using as search words ‘MRI’ and ‘schizophrenia’. MRI studies of first episode patients and chronic patients, suggest reduction of the whole brain volume. Enlargement of lateral ventricles was described as positive in 15 studies out of 19 and was similar to findings in chronic patients. Moreover, for the first episode patients, all data collected point to important changes in medial temporal lobe structures, diminished hippocampal volume, the whole frontal lobe, asymmetry in prefrontal cortex, diminished volume in cingulate, corpus callosum, and cavum septum pellucidum reported abnormalities. MRI is recommended as an important tool in the follow-up process of patients with schizophrenia. Yet, it is still under debate whether the abnormalities described in this condition are able to be used as diagnostic biomarkers.

Parahippocampal area three gray matter is reduced in first-episode schizophrenia spectrum: Discovery and replication samples

Early course schizophrenia is associated with reduced gray matter. The specific structures affected first and how deficits impact symptoms and cognition remain unresolved. We used the Human Connectome Project multimodal parcellation (HCP‐MMP) to precisely identify cortical areas and investigate thickness abnormalities in discovery and replication samples of first‐episode schizophrenia spectrum individuals (FESz). In the discovery sample, T1w scans were acquired from 31 FESz and 31 matched healthy controls (HC). Thickness was calculated for 360 regions in Freesurfer. In the replication sample, high‐resolution T1w, T2w, and BOLD‐rest scans were acquired from 23 FESz and 32 HC and processed with HCP protocols. Thickness was calculated for regions significant in the discovery sample. After FDR correction (q < .05), left and right parahippocampal area 3 (PHA3) were significantly thinner in FESz. In the replication sample, bilateral PHA3 were again thinner in FESz (q < .05). Exploratory correlation analyses revealed left PHA3 was positively associated with hallucinations and right PHA3 was positively associated with processing speed, working memory, and verbal learning. The novel use of the HCP‐MMP in two independent FESz samples revealed thinner bilateral PHA3, suggesting this byway between cortical and limbic processing is a critical site of pathology near the emergence of psychosis.

Progression of neuroanatomical abnormalities after first-episode of psychosis: A 3-year longitudinal sMRI study

The location, extent and progression of longitudinal morphometric changes after first-episode of psychosis (FEP) remains unclear. We investigated ventricular and cortico-subcortical regions over a 3-year period in FEP patients compared with healthy controls. High resolution 1.5T T1-weighted MR images were obtained at baseline from 28 FEP patients at presentation and 28 controls, and again after 3-years. The longitudinal FreeSurfer pipeline (v.5.3.0) was used for regional volumetric and cortical reconstruction image analyses. Repeated-measures ANCOVA and vertex-wise linear regression analyses compared progressive changes between groups in subcortical structures and cortical thickness respectively. Compared with controls, patients displayed progressively reduced volume of the caudate [F (1,51)=5.86, p=0.02, Hedges' g=0.66], putamen [F (1,51)=6.06, p=0.02, g=0.67], thalamus [F (1,51)=6.99, p=0.01, g=0.72] and increased right lateral ventricular volume [F (1, 51)=4.03, p=0.05], and significantly increased rate of cortical thinning [F (1,52)=5.11, p=0.028)] at a mean difference of 0.84% [95% CI (0.10, 1.59)] in the left lateral orbitofrontal region over the 3-year period. In patients, greater reduction in putamen volume over time was associated with lower cumulative antipsychotic medication dose (r=0.49, p=0.01), and increasing lateral ventricular volume over time was associated with worsening negative symptoms (r=0.41, p=0.04) and poorer global functioning (r= -0.41, p=0.04). This study demonstrates localised progressive structural abnormalities in the cortico-striato-thalamo-cortical circuit after the onset of psychosis, with increasing ventricular volume noted as a neuroanatomical marker of poorer clinical and functional outcome.

What a Clinician Should Know About the Neurobiology of Schizophrenia: A Historical Perspective to Current Understanding

The brain is no doubt the "organ" of psychiatry; yet, over the years, few evidence-based classifications of psychiatric disorders have been based on brain mechanisms. The National Institute of Mental Health notably proposed one such system, known as Research Domain Criteria, although it has not yet influenced any changes in the DSM. Of all the major psychiatric disorders, the brain has been studied most extensively in schizophrenia, with its speculative pathology first documented by Emil Kraepelin as early as the beginning of the 20th century. Subsequently, the revolution in technology over the past 50 years has changed how investigators are able to view the brain before death without performing biopsies. Schizophrenia is thus found to have both structural and functional widespread brain anomalies that likely lead to its clinical deterioration. At the onset of illness, acquiring an MRI scan could be part of the routine evaluation to determine how progressive the disease has so far been. However, this practice is not yet recognized by the American Psychiatric Association in any of its guidelines on the treatment of schizophrenia.

Association between cortical volume and gray-white matter contrast with second generation antipsychotic medication exposure in first episode male schizophrenia patients

This cross-sectional study examines the differences in cortical volume and gray-to-white matter contrast (GWC) in first episode schizophrenia patients (SCZ) compared to healthy control participants (HC) and in SCZ patients as a function of exposure to second generation antipsychotic medication. We hypothesize 1) SCZ exhibit regionally lower cortical volumes relative to HCs, 2) cortical volume will be greater with longer exposure to second generation antipsychotics prior to the MRI scan, and 3) lower GWC with longer exposure to second generation antipsychotics prior to the MRI scan, suggesting more blurring from greater intracortical myelin. To accomplish this, MRI scans from 71 male SCZ patients treated with second generation oral risperidone and 42 male HCs were examined. 3D T1-weighted MPRAGE images collected at 1.5T were used to estimate cortical volume and GWC by sampling signal intensity at 30% within the cortical ribbon. Average cortical volume and GWC were calculated and compared between SCZ and HC. Cortical volume and GWC in SCZ patients were correlated with duration of medication exposure for the time period prior to the scan. First-episode SCZ patients had significantly lower cortical volume compared to HCs in bilateral temporal, superior and rostral frontal, postcentral gyral, and parahippocampal regions. In SCZ patients, greater cortical volume was associated with (log-transformed) duration of second-generation antipsychotic medication exposure in bilateral precuneus, right lingual, and right superior parietal regions. Lower GWC was correlated with longer duration of medication exposure bilaterally in the superior frontal lobes. In summary, second generation antipsychotics may increase cortical volume and decrease GWC in first episode SCZ patients.

Prevalence of possible idiopathic normal pressure hydrocephalus in older inpatients with schizophrenia: a replication study

BACKGROUND

We recently reported that older patients with schizophrenia (SZ) show possible idiopathic normal pressure hydrocephalus (iNPH) more frequently than the general population. In this study, we estimated the prevalence of iNPH in a larger number of older SZ patients and explored useful examination values for diagnosis in the SZ population.

METHODS

We enrolled older inpatients with SZ (n = 39, mean age = 68.6 ± 7.7 years) from several psychiatric hospitals in Ehime, Japan and acquired brain imaging data using computed tomography. We evaluated three iNPH symptoms (dementia, gait disturbance, and urinary incontinence). In addition, we combined these data with our previous data to elucidate the relationship between iNPH and characteristics of SZ symptoms.

RESULTS

In total, five (12.8%) patients were diagnosed with possible iNPH. Evans' index for patients with iNPH was significantly higher than for those without iNPH (p = 0.002). The number of disproportionately enlarged subarachnoid space hydrocephalus (DESH) findings was significantly higher in patients with iNPH than in those without iNPH (p <  0.001). Using combined data, Drug-Induced Extra-pyramidal Symptoms Scale (DIEPSS) subscales of gait and bradykinesia showed an increasing trend in the SZ with iNPH group.

CONCLUSIONS

We reconfirmed that older inpatients with SZ experienced possible iNPH more frequently than the general population. We should pay attention to the DIEPSS subscales of gait and bradykinesia and DESH findings in addition to the three main symptoms of iNPH and Evans' index so as to not miss SZ patients with iNPH.

Schizophrenia as a progressive brain disease

There is convincing evidence that schizophrenia is characterized by abnormalities in brain volume. At the Department of Psychiatry of the University Medical Centre Utrecht, Netherlands, we have been carrying out neuroimaging studies in schizophrenia since 1995. We focused our research on three main questions. First, are brain volume abnormalities static or progressive in nature? Secondly, can brain volume abnormalities in schizophrenia be explained (in part) by genetic influences? Finally, what environmental factors are associated with the brain volume abnormalities in schizophrenia?

Based on our findings we suggest that schizophrenia is a progressive brain disease. We showed different age-related trajectories of brain tissue loss suggesting that brain maturation that occurs in the third and fourth decade of life is abnormal in schizophrenia. Moreover, brain volume has been shown to be a useful phenotype for studying schizophrenia. Brain volume is highly heritable and twin and family studies show that unaffected relatives show abnormalities that are similar, but usually present to a lesser extent, to those found in the patients. However, also environmental factors play a role. Medication intake is indeed a confounding factor when interpreting brain volume (change) abnormalities, while independent of antipsychotic medication intake brain volume abnormalities appear influenced by the outcome of the illness.

In conclusion, schizophrenia can be considered as a progressive brain disease with brain volume abnormalities that are for a large part influenced by genetic factors. Whether the progressive volume change is also mediated by genes awaits the results of longitudinal twin analyses. One of the main challenges for the coming years, however, will be the search for gene-by-environment interactions on the progressive brain changes in schizophrenia.

Neuroprogression across the Early Course of Psychosis

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

Mismatch Negativity and Impaired Social Functioning in Long-Term and in First Episode Schizophrenia Spectrum Psychosis

Mismatch negativity (MMN) is elicited by infrequent physical parameter sound changes. MMN to pitch-deviants (pMMN) and duration-deviants (dMMN) are severely reduced in long-term schizophrenia (Sz). Although symptom factors (positive, negative, cognitive) are inconsistently associated with MMN amplitude in Sz, several studies have shown smaller dMMN is associated with impaired social functioning in Sz. MMN is less reduced at the first psychotic episode in the schizophrenia spectrum (FESz). Meta-analyses demonstrate that pMMN is not reduced, while dMMN is moderately impaired. Correlations of pMMN and dMMN with symptom factors in FESz are also equivocal. Associations with social functioning have not been reported. FESz and matched controls (n = 40/group), and Sz and matched controls (n = 50/group) were assessed for baseline and current cognitive functioning, symptoms, and social functioning, and pMMN and dMMN were recorded. Sz showed reductions in pMMN (p = 0.001) and dMMN (p = 0.006) amplitude. By contrast, pMMN (p = 0.27) and dMMN (p = 0.84) were not reduced in FESz. However, FESz showed associations between both MMNs and negative symptoms and social functioning. More impaired MMNs in FESz were associated with increased negative symptoms and impaired social functioning, both current and in the year prior to the emergence of psychosis. These data suggest that the extent of pathological process occurring before first psychosis as reflected in compromised social behavior prior to first break and reduced interpersonal communication and increased alogia at first break is indexed by pMMN and dMMN, putative biomarkers of disease progression sensitive to functional impairment.

Early Detection and Preventive Intervention in Schizophrenia: From Fantasy to Reality

Scientific progress in understanding human disease can be measured by the effectiveness of its treatment. Antipsychotic drugs have been proven to alleviate acute psychotic symptoms and prevent their recurrence in schizophrenia, but the outcomes of most patients historically have been suboptimal. However, a series of findings in studies of first-episode schizophrenia patients transformed the psychiatric field's thinking about the pathophysiology, course, and potential for disease-modifying effects of treatment. These include the relationship between the duration of untreated psychotic symptoms and outcome; the superior responses of first-episode patients to antipsychotics compared with patients with chronic illness, and the reduction in brain gray matter volume over the course of the illness. Studies of the effectiveness of early detection and intervention models of care have provided encouraging but inconclusive results in limiting the morbidity and modifying the course of illness. Nevertheless, first-episode psychosis studies have established an evidentiary basis for considering a team-based, coordinated specialty approach as the standard of care for treating early psychosis, which has led to their global proliferation. In contrast, while clinical high-risk research has developed an evidence-based care model for decreasing the burden of attenuated symptoms, no treatment has been shown to reduce risk or prevent the transition to syndromal psychosis. Moreover, the current diagnostic criteria for clinical high risk lack adequate specificity for clinical application. What limits our ability to realize the potential of early detection and intervention models of care are the lack of sensitive and specific diagnostic criteria for pre-syndromal schizophrenia, validated biomarkers, and proven therapeutic strategies. Future research requires methodologically rigorous studies in large patient samples, across multiple sites, that ideally are guided by scientifically credible pathophysiological theories for which there is compelling evidence. These caveats notwithstanding, we can reasonably expect future studies to build on the research of the past four decades to advance our knowledge and enable this game-changing model of care to become a reality.

Diffusion abnormalities in the corpus callosum in first episode schizophrenia: Associated with enlarged lateral ventricles and symptomatology

INTRODUCTION

Abnormalities in the corpus callosum (CC) and the lateral ventricles (LV) are hallmark features of schizophrenia. These abnormalities have been reported in chronic and in first episode schizophrenia (FESZ). Here we explore further associations between CC and LV in FESZ using diffusion tensor imaging (DTI).

METHODS

. Sixteen FESZ patients and 16 healthy controls (HC), matched on age, gender, and handedness participated in the study. Diffusion and structural imaging scans were acquired on a 3T GE Signa magnet. Volumetric measures for LV and DTI measures for five CC subdivisions were completed in both groups. In addition, two-tensor tractography, the latter corrected for free-water (FA_t), was completed for CC. Correlations between LV and DTI measures of the CC were examined in both groups, while correlations between DTI and clinical measures were examined in only FESZ.

RESULTS

Results from two-tensor tractography demonstrated decreased FA_t and increased trace and radial diffusivity (RD_t) in the five CC subdivisions in FESZ compared to HC. Central CC diffusion measures in FESZ were significantly correlated with volume of the LV, i.e., decreased FA_t values were associated with larger LV volume, while increased RD_t and trace values were associated with larger LV volume. In controls, correlations were also significant, but they were in the opposite direction from FESZ. In addition, decreased FA_t in FESZ was associated with more positive symptoms.

DISCUSSION

Partial volume corrected FA_t, RD_t, and trace abnormalities in the CC in FESZ suggest possible de- or dys-myelination, or changes in axonal diameters, all compatible with neurodevelopmental theories of schizophrenia. Correlational findings between the volume of LV and diffusion measures in FESZ reinforce the concept of a link between abnormalities in the LV and CC in early stages of schizophrenia and are also compatible with neurodevelopmental abnormalities in this population.

Dandy-Walker Malformation-Like Condition Revealed by Refractory Schizophrenia: A Case Report and Literature Review

INTRODUCTION

Dandy-Walker malformation is a rare congenital malformation involving cystic dilatation of the fourth ventricle, enlarged posterior fossa, complete or partial agenesis of the cerebellar vermis, elevated tentorium cerebelli, and hydrocephalus. Previous research highlighted a possible role for the cerebellum in schizophrenia as well as the contribution of underlying brain malformations to treatment resistance. Here, we present a case of a Dandy-Walker malformation-like condition revealed by a refractory schizophrenia in a 24-year-old male patient. We also conduct a literature review of all previously published case reports or case series of co-occurring posterior fossa abnormalities and schizophrenia or psychosis using a PubMed search query to better understand the potential link between these two disorders.

CASE PRESENTATION

A 9-month hospital stay was needed to address the treatment-resistant psychotic symptoms, and the patient continued to experience moderate symptoms despite the prescription of various antipsychotic and antidepressant medications. After an irregular initial medical follow-up, the patient is currently treated with 350 mg daily clozapine and 20 mg daily prazepam and still exhibits moderate anxiety without delirious thoughts, however allowing him to re-enroll at the university. Regarding the literature, 24 cases published between 1996 and 2017 were identified, reviewed and compared to the present case report.

DISCUSSION

This case report and literature review further illuminates the pathophysiology of psychotic disorders including the potential role of the cerebellum, reinforces the importance of a multidisciplinary approach for the neurological and psychiatric management of patients with schizophrenia, and highlights optimal pharmacological management strategies for treatment-resistant schizophrenia.

Age-Related Reduction in Cortical Thickness in First-Episode Treatment-Naïve Patients with Schizophrenia

Substantial evidence supports the neurodevelopmental hypothesis of schizophrenia. Meanwhile, progressive neurodegenerative processes have also been reported, leading to the hypothesis that neurodegeneration is a characteristic component in the neuropathology of schizophrenia. However, a major challenge for the neurodegenerative hypothesis is that antipsychotic drugs used by patients have profound impact on brain structures. To clarify this potential confounding factor, we measured the cortical thickness across the whole brain using high-resolution T1-weighted magnetic resonance imaging in 145 first-episode and treatment-naïve patients with schizophrenia and 147 healthy controls. The results showed that, in the patient group, the frontal, temporal, parietal, and cingulate gyri displayed a significant age-related reduction of cortical thickness. In the control group, age-related cortical thickness reduction was mostly located in the frontal, temporal, and cingulate gyri, albeit to a lesser extent. Importantly, relative to healthy controls, patients exhibited a significantly smaller age-related cortical thickness in the anterior cingulate, inferior temporal, and insular gyri in the right hemisphere. These results provide evidence supporting the existence of neurodegenerative processes in schizophrenia and suggest that these processes already occur in the early stage of the illness.

Age-Related Changes in Topological Degradation of White Matter Networks and Gene Expression in Chronic Schizophrenia

Current hypotheses stipulate core symptoms of schizophrenia (SZ) result from the brain's incapacity to integrate neural processes. Converging diffusion magnetic resonance imaging and graph theory studies provide evidence of macrostructural alterations in SZ. However, age-related topological changes within and between white matter (WM) networks and its relationship to gene expression with disease progression remain incompletely understood. This cross-sectional study uses network modeling to investigate changes in WM network organization with disease progression in chronic SZ as well its relationship with gene expression in healthy brains. First, we replicate prior findings demonstrating altered global WM network topology in SZ. Novel results show significantly altered age-related network degradation patterns in patients compared with controls. Specifically, controls show stereotyped, linear global network decline with age. In contrast, patients show nonlinear network decline with age. Further analysis reveals lack of significant topological decline in younger adult patients, which is subsequently followed by stereotyped linear decline in older adult patients. Node-specific analyses show significant topological differences in frontal and limbic regions of younger adult patients compared with age-matched controls, which become less pronounced with age in older adult patients compared with age-matched controls. Lastly, we show several gene expression profiles, including DISC1, are associated with age-related changes in WM disconnectivity. Together, these findings provide novel WM topological and genetic evidence supporting neurodevelopmental models of SZ, suggesting that network remodeling continues throughout the third decade of life before stabilizing.

Models of Network Spread and Network Degeneration in Brain Disorders

Network analysis can provide insight into key organizational principles of brain structure and help identify structural changes associated with brain disease. Though static differences between diseased and healthy networks are well characterized, the study of network dynamics, or how brain networks change over time, is increasingly central to understanding ongoing brain changes throughout disease. Accordingly, we present a short review of network models of spread, network dynamics, and network degeneration. Borrowing from recent suggestions, we divide this review into two processes by which brain networks can change: dynamics on networks, which are functional and pathological consequences taking place atop a static structural brain network; and dynamics of networks, which constitutes a changing structural brain network. We focus on diffusion magnetic resonance imaging-based structural or anatomic connectivity graphs. We address psychiatric disorders like schizophrenia; developmental disorders like epilepsy; stroke; and Alzheimer's disease and other neurodegenerative diseases.

Cognitive and functional deficits in people with schizophrenia: Evidence for accelerated or exaggerated aging?

Cognitive and functional deficits are commonly seen in people with schizophrenia. The profile of these impairments has a resemblance to the cognitive changes seen in healthy aging. In specific, many of the cognitive ability domains that change the most with aging in healthy people are the most salient of these deficits seen in people with schizophrenia, including prominent deficits in processing speed, working memory, and episodic memory. Functional deficits seen in schizophrenia are also similar to those seen in healthy aging. There is a relationship between multiple psychotic relapses and treatment resistance and longitudinal cognitive and functional changes in schizophrenia, with this relationship starting early in the course of illness. Cognitive performance in people with schizophrenia may be consistent with accelerated or premature aging. People with schizophrenia perform similarly to healthy people who are 3 or more decades older on indices of both cognition and their everyday functional skills. Some people with schizophrenia show exaggerated cognitive changes as well. Cognitive and functional performance worsens at the outset of the illness in schizophrenia compared to premorbid functioning, meaning that these deficits are not due to development disabilities. There are multiple medical and substance abuse comorbidities in schizophrenia and although these comorbidities affect cognitive functioning, they are not completely responsible for age-related changes.

Brain morphology in antipsychotic-naïve schizophrenia: A study of multiple brain structures

Background

Although brain volume changes are found in schizophrenia, only a limited number of structural magnetic resonance imaging studies have exclusively examined antipsychotic-naïve patients.

Aims

To comprehensively investigate multiple brain structures in a single sample of patients who were antipsychotic-naïve.

Method

Twenty antipsychotic-naïve patients with first-episode schizophrenia and 20 healthy comparison subjects were included. Intracranial, total brain, frontal lobe, grey and white matter, cerebellar, hippocampal, parahippocampal, thalamic, caudate nucleus and lateral and third ventricular volumes were measured. Repeated-measures analyses of (co)variance were conducted with intracranial volume as covariate.

Results

Third ventricle volume enlargement was found in patients compared with the healthy subjects. No differences were found in other brain regions.

Conclusions

These findings suggest that some brain abnormalities are present in the early stages of schizophrenia. Moreover, it suggests that brain abnormalities reported in patients with chronic schizophrenia develop in a later stage of the disease and/or are medication induced.

Ventricular enlargement and progressive reduction of cortical gray matter are linked in prodromal youth who develop psychosis

In a recent prospective longitudinal neuroimaging study, clinical high-risk (CHR) individuals who later developed full-blown psychosis showed an accelerated rate of gray matter thinning in superior and medial prefrontal cortex (PFC) and expansion of the ventricular system after applying a stringent correction for multiple comparisons. Although cortical and subcortical volume loss and enlarged ventricles are well characterized structural brain abnormalities among patients with schizophrenia, no prior study has evaluated whether these progressive changes of neuroanatomical indicators are linked in time prior to onset of psychosis. Therefore, we investigated the relationship between the changes in cortical gray matter thickness and ventricular volume using the longitudinal neuroimaging data from the North American Prodrome Longitudinal Study at the whole-brain level. The results showed that ventricular expansion is linked in time to progressive reduction of gray matter, rather than to structural changes in proximal subcortical regions, in a broadly distributed set of cortical regions among CHR youth, including superior, medial, lateral, and inferior PFC, superior temporal gyrus, and parietal cortices. In contrast, healthy controls did not show the same pattern of associations. The main findings were further replicated using a third assessment wave of MRI scans in a subset of study participants who were followed for an additional year. These findings suggest that the gray matter regions exhibiting aberrant rates of thinning in relation to psychosis risk are not limited to the PFC regions that survived the statistical threshold in our primary study, but also extend to other cortical regions previously implicated in schizophrenia.

The Study of the Antisaccade Performance and Contingent Negative Variation Characteristics in First-Episode and Chronic Schizophrenia Patients

The study tested whether the antisaccade (AS) performance and Contingent Negative Variation (CNV) measures differed between the first-episode and chronic patients to provide the evidence of PFC progressive functional deterioration. Subjects included 15 first-episode and 20 chronic schizophrenic patients (with the duration of illness more than 5 years), and 21 control subjects. The first-episode and chronic patients had significantly elevated error percent (p < .05, effect size 1.10 and p < .001, effect size 1.25), increased AS latencies (p < .01, effect size 1.18 and p < .001, effect size 1.69), and increased latencies variability (p < .01, effect size 1.52 and p < .001, effect size 1.37) compared to controls. Chronic patients had marginally significant increase of the response latency (p = .086, effect size .78) and latency variability (p < .099, effect size .63) compared to first-episode ones. Results of CNV analysis revealed that chronic patients only exhibited robustly declined frontal CNV amplitude at Fz (p < .05, effect size .70), F3 (p < .05, effect size .88), and F4 (p < .05, effect size .71) sites compared to controls. The obtained results might be related to specific changes in prefrontal cortex function over the course of schizophrenia.

30 Years on: How the Neurodevelopmental Hypothesis of Schizophrenia Morphed Into the Developmental Risk Factor Model of Psychosis

At its re-birth 30 years ago, the neurodevelopment hypothesis of schizophrenia focussed on aberrant genes and early neural hazards, but then it grew to include ideas concerning aberrant synaptic pruning in adolescence. The hypothesis had its own stormy development and it endured some difficult teenage years when a resurgence of interest in neurodegeneration threatened its survival. In early adult life, it over-reached itself with some reductionists claiming that schizophrenia was simply a neurodevelopmental disease. However, by age 30, the hypothesis has matured sufficiently to incorporated childhood and adult adversity, urban living and migration, as well as heavy cannabis use, as important risk factors. Thus, it morphed into the developmental risk factor model of psychosis and integrated new evidence concerning dysregulated striatal dopamine as the final step on the pathway linking risk factors to psychotic symptoms.

Structural neuroimaging across early-stage psychosis: Aberrations in neurobiological trajectories and implications for the staging model

OBJECTIVE

This review critically examines the structural neuroimaging evidence in psychotic illness, with a focus on longitudinal imaging across the first-episode psychosis and ultra-high-risk of psychosis illness stages.

METHODS

A thorough search of the literature involving specifically longitudinal neuroimaging in early illness stages of psychosis was conducted. The evidence supporting abnormalities in brain morphology and altered neurodevelopmental trajectories is discussed in the context of a clinical staging model.

RESULTS

In general, grey matter (and, to a lesser extent, white matter) declines across multiple frontal, temporal (especially superior regions), insular and parietal regions during the first episode of psychosis, which has a steeper trajectory than that of age-matched healthy counterparts. Although the ultra-high-risk of psychosis literature is considerably mixed, evidence indicates that certain volumetric structural aberrations predate psychotic illness onset (e.g. prefrontal cortex thinning), while other abnormalities present in ultra-high-risk of psychosis populations are potentially non-psychosis-specific (e.g. hippocampal volume reductions).

CONCLUSION

We highlight the advantages of longitudinal designs, discuss the implications such studies have on clinical staging and provide directions for future research.

Mismatch Negativity in First-Episode Schizophrenia: A Meta-Analysis

Mismatch negativity (MMN) to deviant stimuli is robustly smaller in individuals with chronic schizophrenia compared with healthy controls (Cohen's d > 1.0 or more), leading to the possibility of MMN being used as a biomarker for schizophrenia. However, there is some debate in the literature as to whether MMN is reliably reduced in first-episode schizophrenia patients. For the biomarker to be used as a predictive marker for schizophrenia, it should be reduced in the majority of cases known to have the disease, particularly at disease onset. We conducted a meta-analysis on the fourteen studies that measured MMN to pitch or duration deviants in healthy controls and patients within 12 months of their first episode of schizophrenia. The overall effect size showed no MMN reduction in first-episode patients to pitch-deviants (Cohen's d < 0.04), and a small-to-medium reduction to duration-deviants (Cohen's d = 0.47). Together, this indicates that pitch-deviant MMN is not a candidate biomarker for schizophrenia prediction, while duration-deviant MMN may hold some promise, albeit nearly a third as large an effect as in chronic schizophrenia. Potential causes for discrepancies between studies are discussed.

Progressive disability and prefrontal shrinkage in schizophrenia patients with poor outcome: A 3-year longitudinal study

INTRODUCTION

Schizophrenia is a severe disabling disorder with heterogeneous illness courses. In this longitudinal study we characterized schizophrenia patients with poor and good outcome (POS, GOS), using functional and imaging metrics. Patients were defined in accordance to Keefe's criteria (i.e. Kraepelinian and non-Kraepelinian patients).

METHODS

35 POS patients, 35 GOS patients and 76 healthy controls (H) underwent clinical, functioning and magnetic resonance imaging (MRI) assessments twice over three years of follow-up. Information on psychopathology, treatment, disability (using the World Health Organization Disability Assessment Scale II, WHO-DAS-2) and prefrontal morphology was collected. Dorsolateral prefrontal cortex (DLPFC) and orbitofrontal cortex (OFC) were manually traced.

RESULTS

At baseline, subjects with POS showed significantly decreased right dorsolateral prefrontal cortex (DLPFC) white matter volumes (WM) compared to healthy controls and GOS patients (POS VS HC, p<0.001; POS vs GOS, p=0.03), with shrinkage of left DLPFC WM volumes at follow up (t=2.66, p=0.01). Also, POS patients had higher disability in respect to GOS subjects both at baseline and after 3years at the WHO-DAS-2 (p<0.05).

DISCUSSION

Our study supports the hypothesis that POS is characterized by progressive deficits in brain structure and in "real-life" functioning. These are particularly notable in the DLPFC.

The role of neuropathological markers in the interpretation of neuropsychiatric disorders: Focus on fetal and perinatal programming

The study of neuropathological markers in patients affected by mental/psychiatric disorders is relevant for the comprehension of the pathogenesis and the correlation with the clinical symptomatology. The neuropathology of Alzheimer's disease (AD) recognizes intraneuronal and extracellular neurofibrillary formation responsible for neuronal degeneration. Immunohistochemical studies discovered many interesting results for a better interpretation of the AD pathogenesis, while the "metal hypothesis" supports that metal ions might differentially influence the formation of amyloid aggregates. The most relevant pathological findings reported in schizophrenia originate from computer assisted tomography (CT), Magnetic Resonance Imaging (MRI) studies and Diffusion Tensor Imaging (DTI), suggesting the brain abnormalities involved in the pathophysiology of schizophrenia. The theory of fetal programming illustrates the epigenetic factors that may act during the intrauterine life on brain development, with relevant consequences on the susceptibility to develop AD or schizophrenia later in life. The neuropathological interpretation of AD and schizophrenia shows that the presence of severe neuropathological changes is not always associated with severe cognitive impairment. A better dialogue between psychiatrics and pathologists might help to halt insurgence and progression of neurodegenerative diseases.

Understanding the pathophysiology of schizophrenia: Contributions from the Melbourne Psychiatric Brain Bank

The Melbourne Psychiatric Brain Bank came into existence 25years ago. This review focusses on lines of research that have used tissue from the Brain Bank over periods of time. Hence there is a discussion on the significance of changes in levels of serotonin 2A receptors in the cortex of patients with schizophrenia and the relevance of such changes with regards to the pathophysiology of the disorder. The extensive contribution made by studies using tissue from the Melbourne Psychiatric Brain Bank to understanding the role of muscarinic receptors in the pathophysiology and treatment of schizophrenia is summarised. Finally, findings using brain bank tissue and "omics" technologies are reviewed. In each case, findings using tissue from the Melbourne Psychiatric Brain Bank is placed in context with research carried out on human postmortem CNS in schizophrenia and with findings in other lines of research that can help explain the causes or consequences of changes in CNS molecular cytoarchitecture. This timely review of data from the Melbourne Psychiatric Brain Bank reinforces the challenges faced in trying to increase our understanding of the molecular pathophysiology of schizophrenia. Continuing to increase our understanding of the disorder is important as a precursor to identifying new drug targets that can be exploited to improve the treatment of a disorder where treatment resistance remains a significant problem (Millan et al., 2016).

Treatment resistant schizophrenia: Course of brain structure and function

Approximately 30% of people with schizophrenia manifest a minimal response to conventional and atypical antipsychotic medications and manifest continuous symptoms of psychosis, with this condition referred to as "treatment resistant schizophrenia (TRS)". There are several neurobiological consequences of continuous psychosis, including regional cortical atrophy and ventricular enlargement. Pharmacological treatments are available for TRS, with at least 1/3 of patients responding to treatment with clozapine. In this paper we review the evidence regarding the course of treatment resistant schizophrenia, as well as changes in brain structure and function in psychosis and on the possible role of clozapine treatment in altering cortical deterioration in patients with TRS.

Β-Amyloid Burden is Not Associated with Cognitive Impairment in Schizophrenia: A Systematic Review

Current literature suggests that the pathology of schizophrenia (SCZ) has developmental origins. However, the neurodevelopmental theory of SCZ cannot solely explain progressive neurodegenerative processes in the illness. There is evidence of accelerated cognitive decline and increased risk of dementia in elderly patients with SCZ. Investigating β-amyloid (Aβ), we conducted a systematic review focusing on Aβ in patients with SCZ. An OVID literature search using PsychINFO, Medline, and Embase databases was conducted, looking for studies that compared Aβ levels between patients with SCZ and either elderly control subjects, patients with Alzheimer disease (AD), or patients with other psychiatric illnesses. Among 14 identified studies, 11 compared Aβ between SCZ and elderly control subjects, 7 between SCZ and AD, and 3 between SCZ and other psychiatric illnesses. As a result, no evidence was found suggesting that Aβ levels differ in patients with SCZ from elderly control subjects or patients with other psychiatric illnesses. All seven studies reported lower cortical Aβ in patients with SCZ than patients with AD. Furthermore, three of the four studies, which investigated the relationship between Aβ and cognitive impairment in SCZ, observed no association between two factors. The limitations of the included studies are small sample sizes, the inclusion of cerebrospinal fluid Aβ or postmortem plaques rather than cortical Aβ assessment in vivo, and the investigation of different brain regions. In conclusion, Aβ deposition is not associated with cognitive decline in late-life SCZ. Future studies should investigate other neurodegenerative indicators in SCZ to better understand the pathophysiologic mechanisms underlying this illness.

Atypical psychotic symptoms and Dandy-Walker variant

New-onset psychotic symptoms often respond well to antipsychotic treatment; however, symptoms may be difficult to treat when an underlying brain malformation is present. Here, we present a case of atypical psychotic symptoms in the context of a congenital cerebellar malformation (Dandy-Walker variant). The patient ultimately improved with paliperidone palmitate after multiple antipsychotic medication trials (both oral and one long-acting injectable) were ineffective. Neuroimaging may provide valuable diagnostic and prognostic information in cases of new-onset psychosis with atypical features and treatment resistance, even in the absence of neurologic signs and symptoms.

Risk of idiopathic normal pressure hydrocephalus in older inpatients with schizophrenia

BACKGROUND

The mean age of inpatients with schizophrenia has gradually increased in Japan and the risk of fracture in older schizophrenia patients is elevated. One possible cause may be idiopathic normal pressure hydrocephalus (iNPH). The present study aimed to evaluate the prevalence and symptoms of iNPH in older inpatients with schizophrenia.

METHODS

We prospectively examined older inpatients with schizophrenia (N = 21, mean age = 70.5 ± 5.9) in a psychiatric ward. We evaluated iNPH symptoms using the idiopathic Normal-Pressure Hydrocephalus Grading Scale (iNPHGS), Timed Up-and-Go test (TUG), Gait Status Scale (GSS), Mini-Mental State Examination (MMSE), and Neuropsychiatric Inventory (NPI). We also evaluated symptoms of schizophrenia using the Brief Psychiatric Rating Scale (BPRS) and Drug-Induced Extrapyramidal Symptoms Scale (DIEPSS). We conducted cerebrospinal fluid (CSF) tap tests for patients with possible-iNPH.

RESULTS

In total, three (14.3%) patients were diagnosed with possible iNPH: age, GS-Gait, GS-Cognition, TUG, 10-meter walking test, GSS, and DIEPSS were significantly increased in these compared to patients without iNPH; however, GS-Urine, MMSE, NPI, and BPRS did not differ significantly. Probable iNPH was diagnosed for two (9.5%) patients because of positive CSF tap tests.

CONCLUSION

The prevalence of possible and probable iNPH in older patients with schizophrenia was much higher than that reported for older people without mental illness. Of the symptoms evaluated with the tests employed, only gait disturbances, particularly walking speed, distinguished schizophrenia patients with iNPH. These findings suggest that we should pay more attention to the possibility of iNPH in older patients with schizophrenia.

Longitudinal regional brain volume loss in schizophrenia: Relationship to antipsychotic medication and change in social function

BACKGROUND

Progressive brain volume loss in schizophrenia has been reported in previous studies but its cause and regional distribution remains unclear. We investigated progressive regional brain reductions in schizophrenia and correlations with potential mediators.

METHOD

Participants were drawn from the Northern Finland Birth Cohort 1966. A total of 33 schizophrenia individuals and 71 controls were MRI scanned at baseline (mean age=34.7, SD=0.77) and at follow-up (mean age=43.4, SD=0.44). Regional brain change differences and associations with clinical mediators were examined using FSL voxelwise SIENA.

RESULTS

Schizophrenia cases exhibited greater progressive brain reductions than controls, mainly in the frontal and temporal lobes. The degree of periventricular brain volume reductions were predicted by antipsychotic medication exposure at the fourth ventricular edge and by the number of days in hospital between the scans (a proxy measure of relapse duration) at the thalamic ventricular border. Decline in social and occupational functioning was associated with right supramarginal gyrus reduction.

CONCLUSION

Our findings are consistent with the possibility that antipsychotic medication exposure and time spent in relapse partially explain progressive brain reductions in schizophrenia. However, residual confounding could also account for the findings and caution must be applied before drawing causal inferences from associations demonstrated in observational studies of modest size. Less progressive brain volume loss in schizophrenia may indicate better preserved social and occupational functions.

The cerebellum and psychiatric disorders

The cerebellum has been considered for a long time to play a role solely in motor coordination. However, studies over the past two decades have shown that the cerebellum also plays a key role in many motor, cognitive, and emotional processes. In addition, studies have also shown that the cerebellum is implicated in many psychiatric disorders including attention deficit hyperactivity disorder, autism spectrum disorders, schizophrenia, bipolar disorder, major depressive disorder, and anxiety disorders. In this review, we discuss existing studies reporting cerebellar dysfunction in various psychiatric disorders. We will also discuss future directions for studies linking the cerebellum to psychiatric disorders.

Prodromal Symptom Severity Predicts Accelerated Gray Matter Reduction and Third Ventricle Expansion Among Clinically High Risk Youth Developing Psychotic Disorders

A recent prospective longitudinal neuroimaging study of 274 prodromal risk syndrome subjects revealed that those who later developed full-blown psychotic symptoms exhibited accelerated gray matter loss and third ventricle expansion around the time of onset of psychosis. Previous studies also indicate that higher levels of unusual thought content during prodromal states are a significant predictor of psychosis in clinically high-risk youth (CHR). However, the relationship between clinical symptoms and changes in neuroanatomical structure has not been previously examined in the North American Prodrome Longitudinal Study (NAPLS) sample at the atlas level. In this report, we investigated whether symptom severity as measured by the Scale of Prodromal Symptoms (SOPS) predicted the accelerated gray matter decline in 274 CHR cases, including 35 who converted to psychosis. Higher levels of unusual thought content (pre-delusional) symptoms at baseline were associated with a steeper rate of gray matter loss in the prefrontal cortex bilaterally among converters. In contrast, there was no association found among non-converters. Steeper gray matter loss seems to be unique to those (CHR) individuals with higher levels of sub-psychotic pre-delusional symptoms that acutely worsen in the ramp-up to full-blown psychosis, and as such may reflect pathophysiological processes driving emergence of psychosis.

Cognitive correlates of gray matter abnormalities in adolescent siblings of patients with childhood-onset schizophrenia

Patients with childhood onset schizophrenia (COS) display widespread gray matter (GM) structural brain abnormalities. Healthy siblings of COS patients share some of these structural abnormalities, suggesting that GM abnormalities are endophenotypes for schizophrenia. Another possible endophenotype for schizophrenia that has been relatively unexplored is corticostriatal dysfunction. The corticostriatal system plays an important role in skill learning. Our previous studies have demonstrated corticostriatal dysfunction in COS siblings with a profound skill learning deficit and abnormal pattern of brain activation during skill learning. This study investigated whether structural abnormalities measured using volumetric brain morphometry (VBM) were present in siblings of COS patients and whether these were related to deficits in cognitive skill learning. Results revealed smaller GM volume in COS siblings relative to controls in a number of regions, including occipital, parietal, and subcortical regions including the striatum, and greater GM volume relative to controls in several subcortical regions. Volume in the right superior frontal gyrus and cerebellum were related to performance differences between groups on the weather prediction task, a measure of cognitive skill learning. Our results support the idea that corticostriatal and cerebellar impairment in unaffected siblings of COS patients are behaviorally relevant and may reflect genetic risk for schizophrenia.