bluuebunny/crossref_metadata_2025_split huggingface dataset:
S131. NEIGHBOURHOOD-LEVEL SOCIAL CAPITAL, MARGINALIZATION, AND THE INCIDENCE OF PSYCHOTIC DISORDERS IN TORONTO, CANADA: A RETROSPECTIVE POPULATION-BASED COHORT STUDY
Authors: Rotenberg Martin , Tuck Andrew , Anderson Kelly , McKenzie Kwame 
Published: May 2020

Abstract

Background
Previous studies have shown mixed results regarding the relationship between social capital and the risk of developing a psychotic disorder, and this has yet to be studied in North America. This study aims to examine the relationship between neighbourhood-level social capital, marginalization, and the incidence of psychotic disorders in Toronto, Canada.

Methods
A retrospective cohort of people aged 14 to 40 years residing in Toronto, Canada in 1999 (followed to 2008) was constructed from population-based health administrative data. Incident cases of schizophrenia spectrum psychotic disorders were identified using a validated algorithm. Voter participation rates in a municipal election were used as a proxy neighbourhood-level indicator of social capital. Exposure to neighbourhood-level marginalization was obtained from the Ontario Marginalization Index. Poisson regression models adjusting for age and sex were used to calculate incidence rate ratios (IRR) for each social capital quintiles and marginalization quintile.

Results
In the study cohort (n = 640,000) over the 10-year follow-up period, we identified 4,841 incident cases of schizophrenia spectrum psychotic disorders. We observed elevated rates of psychotic disorders in areas with the highest levels (IRR = 1.13, 95% CI 1.00–1.27) and moderate levels (IRR = 1.23, 95% CI 1.12–1.36) of social capital, when compared to areas with the lowest levels of social capital, after adjusting for neighbourhood-level indicators of marginalization. The risk associated with social capital was not present when analyzed in only the females in the cohort. All neighbourhood marginalization indicators, other than ethnic concentration, were significantly associated with risk.

Discussion
The risk of developing a psychotic disorder in Toronto, Canada is associated with socioenvironmental exposures. Social capital is associated with risk, however, the impact of social capital on risk differs by sex and social capital quintile. Across the entire cohort, exposure to all neighbourhood-level marginalization indicators, except ethnic concentration, impacts risk. Future research should examine how known individual-level risk factors, including immigration, ethnicity, and family history of a mental disorder may interact with these findings.
S139. PROGRESSIVE DETERIORATION OF WHITE MATTER TRACTS IN SCHIZOPHRENIA: A DIFFUSION MRI STUDY ON A LARGE SINGLE COHORT USING NORMATIVE MODELS
Authors: Hwang Tzung-Jeng , Tung Yu-Hung , Chen Chang-Le , Yang Li-Ying , Hsu Yung-Chin , Hwu Hai-Gwo , Liu Chen-Chung , Chien Yi-Ling , Hsieh Ming-Hsien , Lin Yi-Tin , Liu Chih-Min , Isaac Tseng Wen-Yih 
Published: May 2020

Abstract

Background
Current diffusion MRI studies of schizophrenia are limited by methodology and sample size. With normative models and the largest single-site cohort, we aimed to delineate a comprehensive profile of tract alteration in unaffected siblings, first-episode schizophrenia (FES), and chronic schizophrenia.

Methods
A total of 277 patients with schizophrenia, 81 unaffected siblings, and 1023 healthy people underwent diffusion-weighted imaging on the same 3T scanner. Generalized fractional anisotropy (GFA), mean diffusivity (MD), radial diffusivity (RD), and axial diffusivity (AD), were sampled along 45 major neural tracts. A normative model was built from the images of 1023 healthy people; Z scores represented the normalized deviation of the index value from that of the age- and sex-matched healthy population.

Results
Widespread involvement of neural tracts was found in patients with FES, and the tracts connecting the prefrontal lobe were the most severely affected. In patients with chronic schizophrenia, virtually all neural tracts were altered, with the tracts connecting the sensorimotor cortex the least affected. A significant negative correlation was observed between GFA alterations and the duration of illness. In unaffected siblings, scattered tracts were involved in GFA, but not in MD or RD.

Discussion
The study revealed widespread white matter involvement in the early stages of schizophrenia. The alteration continues to progress from the neural tracts connecting the prefrontal lobe to the entire brain. Compared to a large sample of normal controls, the attenuated peak and rapid decline of white matter GFA across the lifespan suggest that schizophrenia is associated with neurodevelopmental and neurodegenerative abnormalities of white matter.
S145. CORTICO-THALAMIC DYSCONNECTIVITY LINKS WITH ABERRANT STRIATAL DOPAMINE IN SCHIZOPHRENIA A SIMULTANEOUS 18F-DOPA-PET/RESTING-STATE FMRI STUDY
Authors: Avram Mihai , Brandl Felix , Knolle Franziska , Cabello Jorge , Leucht Claudia , Scherr Martin , Mustafa Mona , Koutsouleris Nikolaos , Leucht Stefan , Ziegler Sibylle , Sorg Christian 
Published: May 2020

Abstract

Background
In schizophrenia, among the most consistent brain changes are both aberrant dopamine function in the dorsal striatum and aberrant intrinsic functional connectivity (iFC) between distinct cortical networks and thalamic nuclei; however, it is unknown whether these changes are pathophysiologically related. Such a relationship is expected because cortico-thalamic-connectivity is modulated by striatal dopamine within topographically distinct, parallel but interacting cortico-basal-ganglia-thalamic circuits. We hypothesized: (1) Within-circuits, aberrant striatal dopamine contributes to aberrant cortico-thalamic-iFC, specifically, associative-striatum dopamine contributes to salience-network-thalamic-iFC, and sensorimotor-striatum dopamine to auditory-sensorimotor-network-thalamic-iFC. (2) Due to between-circuits interactions following an anterior-to-posterior gradient, salience-network-centered-system changes contribute to auditory-sensorimotor-network-centered-system changes.

Methods
To test these hypotheses, 19 patients with schizophrenia during symptomatic remission of positive symptoms and 19 age- and sex-comparable controls underwent simultaneous fluorodihydroxyphenyl-L-alanine positron emission tomography (18F-DOPA-PET) and resting-state functional magnetic resonance imaging (rs-fMRI). The influx constant kicer based on 18F-DOPA-PET was used to measure dopamine synthesis capacity (DSC), indicating striatal dopamine function; correlation coefficients between rs-fMRI time-series of cortical networks and thalamic regions-of-interest were used to measure iFC.

Results
In the salience-network(SAL)-centered-system, patients had reduced associative-striatum-DSC, which correlated positively with SAL-mediodorsal-thalamus-iFC and mediated the reduction of SAL-thalamic-iFC in patients. In the auditory-sensorimotor-network(ASM)-centered-system, patients had reduced sensorimotor-striatum-DSC, which correlated positively with ASM-ventrolateral-thalamus-iFC, but did not mediate increased ASM-thalamic-iFC in patients. Finally, aberrant DSC and iFC of the SAL-centered-system mediated corresponding changes in the ASM-centered-system.

Discussion
Results demonstrate that cortico-thalamic-dysconnectivity links with aberrant striatal dopamine in schizophrenia - in a topographically distinct way, with an anterior-to-posterior gradient, and primary changes in the SAL-centered system.
S150. EMOTIONAL BEHAVIOUR IN HIGH-RISK AND FIRST-EPISODE PSYCHOSIS
Authors: Falkenberg Irina , Tseng Huai-Hsuan , Modinos Gemma , Wild Barbara , McGuire Philip , Allen Paul 
Published: May 2020

Abstract

Background
Studies indicate that people with schizophrenia and first-episode psychosis experience deficits in their ability to accurately detect and display emotions through facial expressions, and that functioning and symptoms are associated with these deficits. This study aims to examine how emotion recognition and facial emotion expression are related to functioning and symptoms in a sample of individuals at ultra-high risk, first-episode psychosis and healthy controls.

Methods
During fMRI, we combined the presentation of emotional faces with the instruction to react with facial movements predetermined and assigned. 18 patients with first-episode psychosis (FEP), 18 individuals at ultra high risk of psychosis (UHR) and 22 healthy controls (HCs) were examined while viewing happy, sad, or neutral faces and were instructed to simultaneously move the corners of their mouths either (a). upwards or (b). downwards, or (c). to refrain from movement. The subjects’ facial movements were recorded with an MR-compatible video camera.

Results
Neurofunctional and behavioral response to emotional faces were measured. Analyses have only recently commenced and are ongoing. Full results of the clinical and functional impact of behavioral and neuroimaging results will be presented at the meeting.

Discussion
Increased knowledge about abnormalities in emotion recognition and behaviour as well as their neural correlates and their impact on clinical measures and functional outcome can inform the development of novel treatment approaches to improve social skills early in the course of schizophrenia and psychotic disorders.
S152. DIAGNOSTIC CLASSIFICATION OF SCHIZOPHRENIA USING 3D CONVOLUTIONAL NEURAL NETWORK WITH RESTING-STATE FUNCTIONAL MRI
Authors: Kim Harin , Woo Joo Sung , Ho Joo Yeon , Lee Jungsun 
Published: May 2020

Abstract

Background
Several machine-learning (ML) algorithms have been deployed in the diagnostic classification of schizophrenia. Compared to other ML methods, the 3D convolutional neural network (CNN) has an advantage of learning complex and subtle patterns in data and preserving spatial information, which is a more suitable tool for brain imaging data. Although resting-state functional MRI (rsfMRI) data has been used in previous ML studies relating to the diagnostic classification of schizophrenia, a limited number of studies have been conducted using resting-state functional connectivity resulted from group independent component analysis (ICA) and dual regression. The objective of this study was to investigate whether a successful diagnostic classification of schizophrenia vs. healthy controls could be achieved by the 3D CNN using resting-state networks in which areas with a significant group difference in activity existed.

Methods
T1 and rsfMRI data were collected in 46 patients with recent-onset schizophrenia and 22 healthy controls. In the pre-processing steps of rsfMRI, the ICA-based automatic removal of motion artifacts was applied to subject-level ICA results and the resulting rsfMRI data were temporally concatenated for group ICA and dual regression. The executive control and auditory networks had areas with significantly higher activity in the control group compared with the patient group. The independent components (ICs) respective to the executive control and auditory networks were used as input for the 3D CNN model which was developed to discriminate the schizophrenia patients from the healthy controls.

Results
The 3D CNN model using the executive control and auditory networks as inputs showed classification accuracies of 65~70%, and error rates of 30~35% approximately.

Discussion
Our findings suggest that the 3D CNN model using rsfMRI data can be useful for learning patterns implicated in schizophrenia and identifying discriminative patterns of schizophrenia in brain imaging data.
S154. TOBACCO SMOKING AND CLINICAL HIGH RISK: A SYSTEMATIC REVIEW AND META-ANALYSIS OF THE EVIDENCE
Authors: De Micheli Andrea , van Lawick van Pabst Albertine , Yossef Enass , McGuire Philip , Fusar-Poli Paolo 
Published: May 2020

Abstract

Background
There is converging evidence that youths at clinical high risk (CHR) are not only likely to develop the first episode of psychosis but also to develop poor physical outcomes. Some physical health risk factors - such as smoking - have been shown to increase the probability of a frank onset of psychosis in those at risk. A meta-analysis conducted in psychotic patients confirmed that daily tobacco use is associated with an increased risk of psychosis. A significant association between any attenuated psychotic symptoms (that characterize CHR state) and cigarette smoking has been recently shown in a study conducted in South London.
Nowadays, it is not completely clear how these findings would translate to the CHR population but a better understanding of how physical health parameters could affect psychopathological outcomes could be beneficial for these vulnerable clinical populations. To shed light on the percentage of smokers in CHR populations, an updated systematic review and meta-analysis of the literature has been carried out. Our main aim was to test whether the probability of being a smoker was higher in the CHR subjects or in the control group.

Methods
The literature search was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. We systematically scrutinized from literature inception to 2019 the following on-line databases: Web of Science Core Collection, BIOSIS Citation Index, KCL-Korean Journal Database, MEDLINE, Russian Science Citation Index, SCiELO Citation Index.
We have considered all the relevant studies reporting the smoking status in CHR subjects and in control groups.
We used the odds ratio (OR) as effect size measure and data were pooled using a random effect approach.

Results
Preliminary data show that CHR individuals were more likely to use tobacco that matched healthy controls. Specifically, the overall OR of 2.016 (p&lt;.001 95%CI=1.476–2.749) indicated a higher likelihood that CHR individuals would use tobacco compared to controls. Heterogeneity was not significant (I²=30.193 p=0.11). The visual inspection of funnel plots did not reveal a clear suggestion for publication bias and the Egger’s test was non-significant (p=0.10).

Discussion
Our systematic review and meta-analysis suggest that is crucial to investigate physical health outcomes such as tobacco use as part of clinical practice in CHR services. Unfortunately, current CHR assessment tools are entirely based on the measurement of psychopathological features and do not include an assessment of these parameters on a regular basis.
S156. PUBLIC ATTENTION TO CRIME OF SCHIZOPHRENIA AND ITS CORRELATION WITH USE OF MENTAL HEALTH SERVICES IN PATIENTS WITH SCHIZOPHRENIA
Authors: Park Hyunwoo , Lee Yu Sang , Yup Lee Sang , Lee Seungyeoun , Sue Hong Kyung , Koike Shinsuke , Soo Kwon Jun 
Published: May 2020

Abstract

Background
This study was performed to examine the effects of the public attention to ‘crime of schizophrenia’ on the use of mental health services in patients with schizophrenia using big data analysis in Korea.

Methods
Data on the frequency of internet searches for ‘crime of schizophrenia’ and the patterns of mental health service utilization by patients with schizophrenia spectrum disorders by month were collected from Naver big data and the Health Insurance Review and Assessment Services in Korea, respectively. Their correlations in the same and following month for lagged effect were examined.

Results
The number of outpatients correlated negatively with public attention to ‘crime of schizophrenia’ in the same month. The lagged relationship between public attention and the number of admissions in psychiatric wards was also found. In terms of sex differences, the use of outpatient services among female patients correlated negatively with public attention in the same month while the number of male patients’ admissions in both same and following month correlated positively with public attention.

Discussion
These findings suggested that public attention to ‘crime of schizophrenia’ could negatively affect illness behavior in patients with schizophrenia.
S163. GLUTAMATERGIC METABOLITES IN THE PSYCHOSIS SPECTRUM: FROM HIGH RISK SAMPLES TO FIRST EPISODE PSYCHOSIS
Authors: Fortea Adriana , Masias Mireia , Pariente Jose , Ilzarbe Daniel , Badia Francina , Valli Isabel , De la Serna Elena , Baeza Inmaculada , Castro-Fornieles Josefina , Sugranyes Gisela 
Published: May 2020

Abstract

Background
The N-methyl-D-aspartate receptor hypofunction model of schizophrenia suggests that dysfunction of these receptors leads to an excess release of glutamate and could explain the brain structural abnormalities characterizing these patients. However, glutamatergic pathways underlying transition to psychosis are yet unclear.

Methods
Youth with recent onset psychosis (FEP), within the first 5 years of disease, individuals with high risk for psychosis (HR) –including participants with psychosis risk syndrome meeting SIPS/SOPS criteria and offspring of parents with bipolar disorder or schizophrenia –, and healthy volunteers, were recruited and scanned with a 3T Siemens scanner. Magnetic resonance spectroscopy was performed using a 2x2x2 cm3 voxel (VOI) placed in the middle frontal region. Ratios of glutamate (Glu), and glutamate + glutamine (Glx) were quantified using LCModel.

Results
18 adolescents with FEP, 33 HR and 32 healthy controls (HC) were included in the analysis. There were no significant differences between groups in mean age (16.4±2.1 vs 15.7±2.7 vs 16.8±1.9; F=2.0, p=.139), but there were trend-level differences in gender (%females: 33.3% vs 57.6% vs 68.8%; Х2=5.9, p=.052). Multivariate models controlling for gender showed a trend-level effect of group in Glu (F=2.9, p=.062), but not in Glx. Post-hoc pairwise contrasts for Glu revealed significantly higher Glu levels in HR individuals (1.38±0.16) compared to FEP (1.27±0.20) and HC (1.31±0.15).

Discussion
Our findings support that increased Glu in the prefrontal cortex may index risk of psychosis from the early stages of the disease, during adolescence. Our observations suggest a possible hyperglutamatergia in premorbid stages that may normalize –or even decrease – after illness onset, possibly related to treatment or compensatory mechanisms. While requiring replication in a larger sample and including follow-up through transition in HR individuals, our findings raise the possibility that abnormal glutamatergic metabolism in the prefrontal cortex could be used as a potential biomarker of illness and putative treatment target.
S166. EFFECTIVE CONNECTIVITY OF FRONTOSTRIATAL SYSTEMS IN FIRST-EPISODE PSYCHOSIS
Authors: Sabaroedin Kristina , Razi Adeel , Aquino Kevin , Chopra Sidhant , Finlay Amy , Nelson Barnaby , Allott Kelly , Alvarez-Jimenez Mario , Graham Jessica , Baldwin Lara , Tahtalian Steven , Yuen Hok P , Harrigan Susy , Cropley Vanessa , Pantelis Christos , Wood Stephen , O’Donoghue Brian , Francey Shona , McGorry Patrick , Fornito Alex 
Published: May 2020

Abstract

Background
Neuroimaging studies have found dysconnectivity of frontostriatal circuits across a broad spectrum of psychotic symptoms. However, it is unknown whether dysconnectivity within frontostriatal circuits originates from disrupted bottom-up or top-down control signaling within these systems. Here, we used dynamic causal modelling (DCM) to examine the effective connectivity of frontostriatal systems in first-episode psychosis (FEP).

Methods
A total of 55 FEP patients (26 males; mean [SD] age = 19.24 [2.89]) and 24 healthy controls (15 males; mean [SD] age = 21.83 [1.93]) underwent a resting-state functional magnetic resonance imaging protocol. Biologically plausible connections between eight left hemisphere regions encompassing the dorsal and ventral frontostriatal systems were modelled using spectral DCM. The regions comprise dorsolateral prefrontal cortex, ventromedial prefrontal cortex, anterior hippocampus, amygdala, dorsal caudate, nucleus accumbens, thalamus, and the midbrain. Effective connectivity between groups were assessed using a parametric Bayesian model. Associations between effective connectivity parameters and positive symptoms, measured by the Brief Psychiatric Rating Scale positive subscale, was assessed in the patient group in a separate Bayesian general linear model.

Results
DCM shows evidence for differences in effective connectivity between patients and healthy controls, namely in the bottom-down connections distributed in the frontostriatal system encompassing the hippocampus, amygdala, striatum, and midbrain. Compared to healthy controls, patients also demonstrated increased disinhibition of the midbrain. In patients, positive symptoms are associated with increased top-down connections to the midbrain. Outgoing connection from the midbrain to the nucleus accumbens is also increased in association with positive symptoms.

Discussion
Aberrant top-down connectivity in the frontostriatal system in patients is consistent with top-down dysregulation of dopamine function in FEP, as dopaminergic activity in the midbrain is proposed to be under the control of higher brain areas. In patients, increased self-inhibition of the midbrain, as well as symptom associations in both ingoing and outgoing connections of this region, are congruous with hyperactivity of the midbrain as proposed by the dopamine dysregulation hypothesis. Here, we demonstrate that mathematical models of brain imaging signals can be used to identify the key disruptions driving brain circuit dysfunction, identifying new targets for treatment.
S167. THE EFFECT OF THE CATECHOL-O-METHYLTRANSFERASE VAL153MET POLYMORPHISM ON TEMPORAL INTERHEMISPHERIC CONNECTIVITY AND LANGUAGE COMPREHENSION IN PATIENTS WITH SCHIZOPHRENIA
Authors: Eun Kim Sung , Soo Lee Kang , Hoon Kim Jeong , Bang Minji , Lee Sang-Hyuk 
Published: May 2020

Abstract

Background
Difficulties in language comprehension is the major psychopathology in schizophrenia. The catechol-O-methyltransferase (COMT) Val153Met polymorphism, a candidate gene related to the pathogenesis of schizophrenia, is associated with higher cognitive abilities including language comprehension. At the brain level, this function is known to be supported by reciprocal communication via transcallosal projections between the temporal regions. This study investigated the effect of the COMT Val153Met polymorphism on white matter (WM) integrity of the tapetum, which connects the bilateral temporal lobes, and language comprehension in patients with schizophrenia.

Methods
Ninety patients with schizophrenia participated in this study. The COMT Val153Met polymorphism was analyzed, and the genotype groups were divided into Val-allele homozygotes and Met-allele carriers (45 participants in each group). Diffusion tensor imaging (DTI) data were acquired from all participants. Fractional anisotropy (FA) values were extracted from the bilateral tapetum. The levels of language comprehension were measured using verbal comprehension subtests of the Korean version of WAIS.

Results
Val-allele homozygotes showed higher FAs in left tapetum than Met-allele carriers (mean ± SD: val-allele homozygotes = 0.809 ± 0.059, Met-allele carriers = 0.777 ± 0.079; t = 2.16, p = 0.034). The right tapetum FAs were not different between two groups. (mean ± SD: val-allele homozygotes = 0.772 ± 0.065, Met-allele carriers = 0.748 ± 0.061; t = 1.83, p = 0.071). Although the sum of verbal comprehension subtest scores did not differ between two groups, only Val-allele homozygotes showed a negative correlation between the sum scores and left tapetum FAs (val-allele homozygotes: r = -0.426, p = 0.021, Met-allele carriers: r = -0.193, p = 0.275).

Discussion
This study suggests that the COMT Val153Met polymorphism may be associated with structural changes in interhemispheric WM tracts connecting the temporal regions. Furthermore, COMT-associated WM changes may contribute to individual variations in language comprehension of patients with schizophrenia, particularly Val-allele homozygotes. We expect that our findings provide some clues for understanding the interaction between the brain and genes in patients with schizophrenia.