Childhood urbanicity is associated with emotional episodic memory-related striatal function and common variation in NTRK2.

BACKGROUND: Childhoods in urban or rural environments may differentially affect the risk of neuropsychiatric disorders, possibly through memory processing and neural response to emotional stimuli. Genetic factors may not only influence individuals' choices of residence but also modulate how the living environment affects responses to episodic memory. METHODS: We investigated the effects of childhood urbanicity on episodic memory in 410 adults (discovery sample) and 72 adults (replication sample) with comparable socioeconomic statuses in Beijing, China, distinguishing between those with rural backgrounds (resided in rural areas before age 12 and relocated to urban areas at or after age 12) and urban backgrounds (resided in cities before age 12). We examined the effect of childhood urbanicity on brain function across encoding and retrieval sessions using an fMRI episodic memory paradigm involving the processing of neutral or aversive pictures. Moreover, genetic association analyses were conducted to understand the potential genetic underpinnings that might contribute to memory processing and neural mechanisms influenced by early-life urban or rural environments. RESULTS: Episodic memory retrieval accuracy for more difficult neutral stimuli was similar between those with urban and rural childhoods, whereas aversive stimuli elicited higher retrieval accuracy in the urban group (P = 0.023). For aversive stimuli, subjects with urban childhood had relatively decreased engagement of the striatum at encoding and decreased engagement of the hippocampus at retrieval. This more efficient striatal encoding of aversive stimuli in those with urban childhoods was associated with common variation in neurotrophic tyrosine kinase receptor type 2 (NTRK2) (right striatum: P = 1.58×10-6). These findings were confirmed in the replication sample. CONCLUSIONS: We suggest that this differential striatal processing of aversive stimuli observed in individuals with urban or rural childhoods may represent mechanisms by which childhood urbanicity may affect brain circuits, heightening behavioral responses to negative stressors associated with urban environments. NTRK2-associated neural processes in the striatum may play a role in these processes.

Effects of parenting styles on adult personality traits, depressive trait, and brain structure.

This study explored the complex triangular relationships between parenting styles, personality traits, and depressive trait in Chinese Han adults (N = 490; Mean age=24.25; 51.0% women), and examined the relationship between parenting styles and brain structure. The data indicated that depressive trait in adulthood were negatively correlated with a favorable parenting style (emotional warmth) and positively correlated with undesirable parenting styles (punishment, rejection, and overprotection/over-intervention). Additionally, depressive trait in adulthood were positively related to neuroticism and psychoticism, and negatively related to extraversion. Using a multiple parallel mediation analysis, we found that neuroticism could be worsened by undesirable parenting styles and ameliorated by favorable parenting styles, and it further mediated the relationship between parenting styles and depressive trait across all models. Psychoticism played a similar role in two models: 1) parental punishment and depressive trait and 2) parental rejection and depressive trait. Extraversion played a mediating role between the father's overprotection and depressive trait. Subgroup analysis showed that different mediating pathways existed between different sexes. In terms of brain structure, we found that gray matter volume of the right inferior frontal gyrus was negatively related to overprotection by the father and positively related to psychoticism. Our findings highlight the importance of parenting style on personality traits, depressive trait, and brain structure over the long term.

The effects of environmental factors associated with childhood urbanicity on brain structure and cognition.

Urbanization is a trend lasting for more than one century worldwide. Four hundred ninety male and female adult Chinese Han participants with different urban and rural childhoods were included in this study. Early-life urban environment was found benefit for total grey matter volume (GMV), dorsolateral prefrontal cortex (DLPFC) GMV, temporal pole (TP) GMV and cognition function, and negatively correlated with medial prefrontal cortex (MPFC) GMV. Regression analysis showed that maternal education was a protective factor for total and DLPFC GMVs, while having siblings was better for MPFC GMV. Total, DLPFC and TP GMVs acts mediation effects between childhood urbanicity and different cognitive domains. These findings may suggest some pros and cons on brain structure associated with childhood urbanicity and related environmental factors.

Metabolic-associated fatty liver disease and risk of esophagogastric cancer: a systematic review and meta-analysis.

INTRODUCTION: Metabolic-associated fatty liver disease (MAFLD) has been found to be strongly linked to several diseases. Although previous studies have explored the association between MAFLD and extrahepatic cancers, research on the relationship between MAFLD and gastric carcinoma (GC) and esophageal carcinoma (EC) is relatively scarce and requires updating. Therefore, the objective of this study is to conduct a comprehensive investigation into the association between MAFLD and GC or EC. MATERIAL AND METHODS: We conducted a comprehensive search for relevant studies published up to 5 August 2022, using the PubMed, Embase and Web of Science databases. To estimate the risk ratio (RR) and the 95% confidence interval (CI), we employed a random-effects model. We also conducted subgroup analyses based on study characteristics. The protocol for this systematic review is registered in the Prospero database under the registration number CRD42022351574. RESULTS: Our analysis included eight eligible studies, comprising a total of 8 629 525 participants. We found that the pooled RR values for the risk of GC in patients with MAFLD were 1.49 (95%CI: 1.17-1.91), whereas the pooled RR values for the risk of EC in patients with MAFLD were 1.76 (95%CI: 1.34-2.32). CONCLUSIONS: Based on our meta-analysis, we conclude that there is a significant association between the presence of MAFLD and the development of GC and EC.

Deep learning predicts DNA methylation regulatory variants in the human brain and elucidates the genetics of psychiatric disorders.

There is growing evidence for the role of DNA methylation (DNAm) quantitative trait loci (mQTLs) in the genetics of complex traits, including psychiatric disorders. However, due to extensive linkage disequilibrium (LD) of the genome, it is challenging to identify causal genetic variations that drive DNAm levels by population-based genetic association studies. This limits the utility of mQTLs for fine-mapping risk loci underlying psychiatric disorders identified by genome-wide association studies (GWAS). Here we present INTERACT, a deep learning model that integrates convolutional neural networks with transformer, to predict effects of genetic variations on DNAm levels at CpG sites in the human brain. We show that INTERACT-derived DNAm regulatory variants are not confounded by LD, are concentrated in regulatory genomic regions in the human brain, and are convergent with mQTL evidence from genetic association analysis. We further demonstrate that predicted DNAm regulatory variants are enriched for heritability of brain-related traits and improve polygenic risk prediction for schizophrenia across diverse ancestry samples. Finally, we applied predicted DNAm regulatory variants for fine-mapping schizophrenia GWAS risk loci to identify potential novel risk genes. Our study shows the power of a deep learning approach to identify functional regulatory variants that may elucidate the genetic basis of complex traits.

Unsuppressed Striatal Activity and Genetic Risk for Schizophrenia Associated With Individual Cognitive Performance Under Social Competition.

BACKGROUND AND HYPOTHESIS: Social competition affects human behaviors by inducing psychosocial stress. The neural and genetic mechanisms of individual differences of cognitive-behavioral response to stressful situations in a competitive context remain unknown. We hypothesized that variation in stress-related brain activation and genetic heterogeneity associated with psychiatric disorders may play roles towards individually differential responses under stress. STUDY DESIGN: A total of 419 healthy subjects and 66 patients with schizophrenia were examined functional magnetic resonance imaging during working memory task including social competition stressors. We explored the correlation between stress-induced brain activity and individual working memory performance. The partial least squares regression was performed to examine the genetic correlates between stress-related activity and gene expression data from Allen Human Brain Atlas. Polygenic risk score (PRS) was used to assess individual genetic risk for schizophrenia. STUDY RESULTS: Greater suppression of bilateral striatal activity was associated with better behavioral improvement in working memory manipulation under social competition (left: rPearson = -0.245, P = 4.0 × 10-6, right: rPearson = -0.234, P = 1.0 × 10-5). Genes transcriptionally related to stress-induced activation were linked to genetic risk for schizophrenia (PFDR < 0.005). Participants with decreased accuracy under social competition exhibited higher PRS of schizophrenia (t = 2.328, P = .021). Patients with schizophrenia showed less suppressed striatal activity under social stress (F = 13.493, P = 3.5 × 10-4). CONCLUSIONS: Striatal activity change and genetic risk for schizophrenia might play a role in the individually behavioral difference in working memory manipulation under stress.

The Systemic Immune-Inflammation Index May Be a Novel and Strong Marker for the Accurate Early Prediction of Acute Kidney Injury in Severe Acute Pancreatitis Patients.

OBJECTIVE: This research was performed to investigate the correlation between acute kidney injury (AKI) and systemic immune-inflammation index (SII) in severe acute pancreatitis (SAP) patients. METHODS: The study included 218 SAP patients from Chongqing Jiangjin Center Hospital during January 2016 to October 2020. The SII was defined as platelet × neutrophil/lymphocyte ratio. After univariate analysis, logistic regression analysis was used for analyzing independent risk factors of AKI in SAP patients. Receiver operating characteristic (ROC) curve was used for analyzing the prognostic value of the SII. RESULTS: AKI occurred in 74 cases and its incidence rate was 33.9%. The median SII value of AKI patients was higher than that of patients without AKI. After multivariate analysis, SII, age, triglyceride (TG), neutrophil ratio (NEU-R), C-reactive protein (CRP), aspartate aminotransferase (AST), and serum albumin (ALB) were independent predictors of AKI. Serum ALB was an independent protective factor. The optimum threshold truncation value of SII was 2880.1*10^9/L. Compared with other inflammatory factors, SII had a better prediction efficiency. CONCLUSION: The SII, TG, NEU-R, CRP, and ALB were significant independent predictors of AKI in SAP patients. Serum TG, NEU-R, CRP, and SII were risk factors. Serum ALB was a protective factor. The SII may be a novel, simple, and strong marker for the accurate early prediction of AKI in SAP patients.

Air pollution interacts with genetic risk to influence cortical networks implicated in depression.

Air pollution is a reversible cause of significant global mortality and morbidity. Epidemiological evidence suggests associations between air pollution exposure and impaired cognition and increased risk for major depressive disorders. However, the neural bases of these associations have been unclear. Here, in healthy human subjects exposed to relatively high air pollution and controlling for socioeconomic, genomic, and other confounders, we examine across multiple levels of brain network function the extent to which particulate matter (PM2.5) exposure influences putative genetic risk mechanisms associated with depression. Increased ambient PM2.5 exposure was associated with poorer reasoning and problem solving and higher-trait anxiety/depression. Working memory and stress-related information transfer (effective connectivity) across cortical and subcortical brain networks were influenced by PM2.5 exposure to differing extents depending on the polygenic risk for depression in gene-by-environment interactions. Effective connectivity patterns from individuals with higher polygenic risk for depression and higher exposures with PM2.5, but not from those with lower genetic risk or lower exposures, correlated spatially with the coexpression of depression-associated genes across corresponding brain regions in the Allen Brain Atlas. These converging data suggest that PM2.5 exposure affects brain network functions implicated in the genetic mechanisms of depression.

Childhood urbanicity interacts with polygenic risk for depression to affect stress-related medial prefrontal function.

Urbanization is increasing globally, and is associated with stress and increased mental health risks, including for depression. However, it remains unclear, especially at the level of brain function, how urbanicity, social threat stressors, and psychiatric risk may be linked. Here, we aim to define the structural and functional MRI neural correlates of social stress, childhood urbanicity, and their putative mechanistic relevance to depressive illness risk, in terms of behavioral traits and genetics. We studied a sample of healthy adults with divergent urban and rural childhoods. We examined childhood urbanicity effects on brain structure as suggested by MRI, and its functional relevance to depression risk, through interactions between urbanicity and trait anxiety-depression, as well as between urbanicity and polygenic risk for depression, during stress-related medial prefrontal cortex (mPFC) engagement. Subjects with divergent rural and urban childhoods were similar in adult socioeconomic status and were genetically homogeneous. Urban childhood was associated with relatively reduced mPFC gray matter volumes as suggested by MRI. MPFC engagement under social status threat correlated with the higher trait anxiety-depression in subjects with urban childhoods, but not in their rural counterparts, implicating an exaggerated physiological response to the threat context with urbanicity, in association with behavioral risk for depression. Stress-associated mPFC engagement also interacted with polygenic risk for depression, significantly predicting a differential mPFC response in individuals with urban but not rural childhoods. Developmental urbanicity, therefore, appears to interact with genetic and behavioral risk for depression on the mPFC neural response to a threat context.

A Scoring System for Surgical Site Infection after Pancreaticoduodenectomy Using Clinical Data.

Object: To analyze the factors influencing surgical site infection (SSI) after pancreaticoduodenectomy and to establish a scoring system for predicting such infections. Methods: Patients who underwent pancreaticoduodenectomy in the Department of Hepatobiliary Surgery of the Second Affiliated Hospital of Chongqing Medical University from January 2015 to March 2019 were divided randomly into a model group and a test group in a proportion of 3:1. According to whether an SSI occurred after operation, the model group was divided into an incision-infection group and a non-infection group. Univariable analysis and multivariable regression analysis were used to analyze factors related to post-operative incision infection and to establish a clinical predictive scoring system. The scoring system was evaluated for the test group. Results: A total of 236 patients, 177 in the model group and 59 in the test group, were included. In the model group, univariable and logistic regression analysis showed that tumor nature (benign versus malignant), post-operative albumin concentration, pancreatic fistula formation, post-operative cough, and peri-operative blood transfusion were the independent risk factors for incision infection. Then we established a clinical predictive scoring system. In the test group, the area under the receiver operator characteristic curve of the system was 0.768 (p < 0.001, with sensitivity = 59.1% and specificity = 94.6%). Conclusion: The scoring system had good clinical prediction ability and high specificity, so it was worth using in the clinic.

Distinct Effects of Social Stress on Working Memory in Obsessive-Compulsive Disorder.

Stress might exaggerate the compulsion and impair the working memory of patients with obsessive-compulsive disorder (OCD). This study evaluated the effect of stress on the cognitive neural processing of working memory in OCD and its clinical significance using a "number calculation working memory" task. Thirty-eight patients and 55 gender- and education-matched healthy controls were examined. Stress impaired the performance of the manipulation task in patients. Healthy controls showed less engagement of the medial prefrontal cortex and striatum during the task under stress versus less stress, which was absent in the patients with OCD. The diagnosis × stress interaction effect was significant in the right fusiform, supplementary motor area, precentral cortex and caudate. The failure of suppression of the medial prefrontal cortex and striatum and stress-related hyperactivation in the right fusiform, supplementary motor area, precentral cortex, and caudate might be an OCD-related psychopathological and neural response to stress.

Parietal-Prefrontal Feedforward Connectivity in Association With Schizophrenia Genetic Risk and Delusions.

OBJECTIVE: Conceptualizations of delusion formation implicate deficits in feedforward information updating across the posterior to prefrontal cortices, resulting in dysfunctional integration of new information about contexts in working memory and, ultimately, failure to update overfamiliar prior beliefs. The authors used functional MRI and machine learning models to address individual variability in feedforward parietal-prefrontal information updating in patients with schizophrenia. They examined relationships between feedforward connectivity, and delusional thinking and polygenic risk for schizophrenia. METHODS: The authors studied 66 schizophrenia patients and 143 healthy control subjects during performance of context updating in working memory. Dynamic causal models of effective connectivity were focused on regions of the prefrontal and parietal cortex potentially implicated in delusion processes. The effect of polygenic risk for schizophrenia on connectivity was examined in healthy individuals. The authors then leveraged support vector regression models to define optimal normalized target connectivity tailored for each patient and tested the extent to which deviation from this target could predict individual variation in severity of delusions. RESULTS: In schizophrenia patients, updating and manipulating context information was disproportionately less accurate than was working memory maintenance, with an interaction of task accuracy by diagnosis. Patients with delusions also tended to have relatively reduced parietal-prefrontal feedforward effective connectivity during context updating in working memory manipulation. The same connectivity was adversely influenced by polygenic risk for schizophrenia in healthy subjects. Individual patients' deviation from predicted "normal" feedforward connectivity based on the support vector regression models correlated with severity of delusions. CONCLUSIONS: These computationally derived observations support a role for feedforward parietal-prefrontal information processing deficits in delusional psychopathology and in genetic risk for schizophrenia.

Nonalcoholic fatty liver disease and mortality from all causes, cardiovascular disease, and cancer: a meta-analysis.

Whether nonalcoholic fatty liver disease (NAFLD) is associated with an increased risk of mortality remains controversial. The present study aimed to clarify this issue. A systematic search of PubMed and Embase was conducted through October 2018. Studies providing risk estimates of NAFLD and mortality were included. A random-effects model was employed to calculate summary risk estimates. Subgroup analyses were performed to identify potential effect modifiers. Fourteen studies, involving 498501 subjects and 24234 deaths, were included. Patients with NAFLD were found to be at an elevated risk of all-cause mortality compared with those without [hazard ratio (HR) = 1.34; 95% confidence interval (CI) 1.17-1.54)]. The significantly positive association between NAFLD and all-cause mortality could not be modified by age, sex, follow-up duration, and adjustment for body mass index, diabetes, smoking or hypertension (all Pinteraction > 0.05), and remained in sensitivity analyses. No significant associations of NAFLD with CVD (HR = 1.13; 95% CI 0.92-1.38) and cancer (HR = 1.05; 95% CI 0.89-1.25) mortality were found. In conclusion, NAFLD is a predictor of increased all-cause mortality but not CVD and cancer mortality. These findings have important implications for decision making in public health and clinical practice, and highlight the urgency of developing effective treatments for NAFLD.

Risk Assessment of Laparoscopic Cholecystectomy in Liver Cirrhotic Patients with Clinically Significant Portal Hypertension: A Retrospective Cohort Study.

Objective: This study was aimed to evaluate the correlation between clinically significant portal hypertension (CSPH) and postoperative complications and risk predictors of postoperative complications. Methods: The retrospective study was conducted to identify the effect. The cirrhotic patients were divided into two groups, those with or without CSPH. The intraoperative and postoperative conditions were evaluated. Multivariate logistic regression analysis was performed to identify potential risk predictors for postoperative complications in cirrhotic patients with CSPH. Results: The cirrhotic patients with CSPH who underwent laparoscopic cholecystectomy (LC) had postoperative hospitalization than the patients without CSPH. However, the incidence of postoperative complications between two groups showed no significant difference. The results of multivariate analysis showed that male, gallbladder wall >3 mm, size of stones ≥1 cm, scores of Model for end-stage liver disease (MELD) ≥10, and operation time >60 minutes were the potential risk predictors for postoperative complications. Conclusions: CSPH did not increase the incidence of postoperative complications in cirrhotic patients who underwent LC, but increased conversion rate and prolonged postoperative hospitalization. Furthermore, our study showed that gender, sizes of gallbladder wall and stones, scores of MELD, and operation time were the important postoperative risk predictors for cirrhotic patients with CSPH.

Shenfu Injection Attenuates Bile Duct Injury in Rats with Acute Obstructive Cholangitis.

Background: We investigated the effect of Shenfu injection (SFI) in Wistar rats with acute obstructive cholangitis (AOC) and considered the possible molecular mechanisms of the effects. Methods: The 96 rats were divided randomly into three groups. In one group, the common bile duct was subjected to ligation (BDL), and 0.2 mL of saline was injected into the proximal bile ducts. To create AOC, again, the common bile duct was ligated, and 0.2 mL of lipopolysaccharide (LPS)) (2 mg/mL) was injected into the proximal ducts. In the Shenfu injection (SFI) group, the material (10 mg/kg) was injected into the tail vein 2 hours before induction of AOC. The hepatic histopathologic changes were observed under a light microscope. The endotoxin, tumor necrosis factor-α (TNF-α), alanine transaminase (ALT), and total bilirubin (TB) concentrations in the serum were measured at different time points (0, 4, 8, and 16 hours) after ligation. The expression of nuclear transcription factor-κB (NF-κB) and CD14 in Kupffer cells also was analyzed at different times by Western blotting. Results: The TNF-α, ALT, and TB concentrations in the serum and the expression of CD14 and NF-κB in Kupffer cells were significantly higher in the SFI group than in the BDL group, but all were significantly lower than in the AOC group. Compared with the AOC group, the edema of cholangiocytes was alleviated in the SFI group, and the infiltration of inflammatory cells around cholangiocytes was reduced. Conclusion: Shenfu injection significantly alleviated bile duct injury. The potential mechanism may be associated with inhibition of CD14 expression and prevention of NF-κB activation in Kupffer cells.

Long-Term Efficacy of Laparoscopic Radiofrequency Ablation in Early Hepatocellular Carcinoma: A Systematic Review and Meta-Analysis.

Objective: The aim of this study was to investigate the long-term efficacy of laparoscopic radiofrequency ablation (LRFA) in early hepatocellular carcinoma (HCC) compared with other surgical procedures. Methods: A literature search of Cochrane library, PubMed, and Embase through October 2018 was conducted by two investigators (J.-F.G. and F.Y.) independently. The quality of included studies was estimated by the Newcastle-Ottawa Scale. Review Manager 5.3 software was used for meta-analysis, and either fixed- or random-effects model was used according to the heterogeneity of included studies. The chi-square test was used for heterogeneity analysis of included studies, and subgroup analysis was conducted to estimate the heterogeneity between each study and also to estimate the efficacy of different studies. Results: A total of 11 studies involving 1691 patients were included in this analysis. Patients undergoing hepatic resection (HR) had higher 3-, 5-year overall survival rate, 3-year disease-free survival rate, and lower local recurrence rate than those undergoing LRFA. However, patients undergoing LRFA had higher 3-, 5-year overall survival rate than those undergoing other minimally invasive ablation, although there was no statistical difference in local recurrence rate or disease-free survival rate. Conclusion: HR is still an ideal choice for early HCC. If minimally invasive ablation is an alternative treatment, LRFA will be better than other minimally invasive options.

Percutaneous Transhepatic Gallbladder Drainage Combined with Laparoscopic Cholecystectomy: A Meta-Analysis of Randomized Controlled Trials.

OBJECTIVE: To investigate the clinical effect of the laparoscopic cholecystectomy (LC) after percutaneous transhepatic gallbladder drainage (PTGD) in elder acute cholecystitis. METHODS: The Cochrane Library, PubMed, China National Knowledge Infrastructure (CNKI), VIP, and Wanfang Databases were searched for randomized controlled trials (RCTs) on LC after PTGD in elder acute cholecystitis published from 1970 to July 2017. Two researchers selected RCTs, extracted data, and evaluated methodological quality independently, and RevMan 5.3 software was used for the meta-analysis. The chi-square test was used for heterogeneity analysis of RCTs included, and the funnel plots were used to evaluate publication bias. RESULTS: A total of 9 RCTs with 1000 patients were included in this analysis. Compared with the direct LC Group, the PTGD Group has significant better effect in operative duration (minutes) [standard mean difference (SMD) = -1.37, 95% confidence interval (95% CI): -2.52 to -0.22, P = .02], the amount of intraoperative bleeding (mL) (SMD = -1.38, 95% CI: -2.11 to -0.65, P = .0002), conversion rate to laparotomy (%) [odds ratio (OR) = 0.16, 95% CI: 0.08 to 0.31, P < .00001], postoperative complication morbidity (%) (OR = 0.29, 95% CI: 0.17 to 0.51, P < .0001), and postoperative hospital stay (days) (SMD = -1.26, 95% CI: -1.94 to -0.59, P = .0003). The funnel plots were slightly asymmetric, which suggested the presence of publication bias. CONCLUSION: The PTGD before scheduled LC can effectively not only shorten operative duration, intraoperative bleeding less, and postoperative hospital stay but also decrease the rate to laparotomy and postoperative complication morbidity in elder acute cholecystitis, and it is recommended to be regarded as the preferred therapy of the elder patients.

Late-Onset Alzheimer's Disease Polygenic Risk Profile Score Predicts Hippocampal Function.

BACKGROUND: We explored the cumulative effect of several late-onset Alzheimer's disease (LOAD) risk loci using a polygenic risk profile score (RPS) approach on measures of hippocampal function, cognition, and brain morphometry. METHODS: In a sample of 231 healthy control subjects (19-55 years of age), we used an RPS to study the effect of several LOAD risk loci reported in a recent meta-analysis on hippocampal function (determined by its engagement with blood oxygen level-dependent functional magnetic resonance imaging during episodic memory) and several cognitive metrics. We also studied effects on brain morphometry in an overlapping sample of 280 subjects. RESULTS: There was almost no significant association of LOAD-RPS with cognitive or morphometric measures. However, there was a significant negative relationship between LOAD-RPS and hippocampal function (familywise error [small volume correction-hippocampal region of interest] p < .05). There were also similar associations for risk score based on APOE haplotype, and for a combined LOAD-RPS + APOE haplotype risk profile score (p < .05 familywise error [small volume correction-hippocampal region of interest]). Of the 29 individual single nucleotide polymorphisms used in calculating LOAD-RPS, variants in CLU, PICALM, BCL3, PVRL2, and RELB showed strong effects (p < .05 familywise error [small volume correction-hippocampal region of interest]) on hippocampal function, though none survived further correction for the number of single nucleotide polymorphisms tested. CONCLUSIONS: There is a cumulative deleterious effect of LOAD risk genes on hippocampal function even in healthy volunteers. The effect of LOAD-RPS on hippocampal function in the relative absence of any effect on cognitive and morphometric measures is consistent with the reported temporal characteristics of LOAD biomarkers with the earlier manifestation of synaptic dysfunction before morphometric and cognitive changes.

Estimating changing contexts in schizophrenia.

SEE STEPHAN ET AL DOI101093/AWW120 FOR A SCIENTIFIC COMMENTARY ON THIS WORK: Real world information is often abstract, dynamic and imprecise. Deciding if changes represent random fluctuations, or alterations in underlying contexts involve challenging probability estimations. Dysfunction may contribute to erroneous beliefs, such as delusions. Here we examined brain function during inferences about context change from noisy information. We examined cortical-subcortical circuitry engaging anterior and dorsolateral prefrontal cortex, and midbrain. We hypothesized that schizophrenia-related deficits in prefrontal function might overestimate context change probabilities, and that this more chaotic worldview may subsequently gain familiarity and be over-reinforced, with implications for delusions. We then examined these opposing information processing biases against less expected versus familiar information patterns in relation to genetic risk for schizophrenia in unaffected siblings. In one experiment, 17 patients with schizophrenia and 24 normal control subjects were presented in 3 T magnetic resonance imaging with numerical information varying noisily about a context integer, which occasionally shifted up or down. Subjects were to indicate when the inferred numerical context had changed. We fitted Bayesian models to estimate probabilities associated with change inferences. Dynamic causal models examined cortical-subcortical circuitry interactions at context change inference, and at subsequent reduced uncertainty. In a second experiment, genetic risk for schizophrenia associated with similar cortical-subcortical findings were explored in an independent sample of 36 normal control subjects and 35 unaffected siblings during processing of intuitive number sequences along the number line, or during the inverse, less familiar, sequence. In the first experiment, reduced Bayesian models fitting subject behaviour suggest that patients with schizophrenia overestimated context change probabilities. Here, patients engaged anterior prefrontal cortex relatively less than healthy controls, in part driven by reduced effective connectivity from dorsolateral prefrontal cortex to anterior prefrontal cortex. In processing subsequent information indicating reduced uncertainty of their predictions, patients engaged relatively increased mid-brain activation, driven in part by increased dorsolateral prefrontal cortex to midbrain connectivity. These dissociable reduced and exaggerated prefrontal and subcortical circuit functions were accentuated in patients with delusions. In the second experiment, analogous dissociable reduced anterior prefrontal cortex and exaggerated midbrain engagement occurred in unaffected siblings when processing less expected versus more familiar number sequences. In conclusion, patients overestimated ambiguous context change probabilities with relatively reduced anterior frontal engagement. Subsequent reduced uncertainty about contextual state appeared over-reinforced, potentially contributing to confirmation bias and a cascade of aberrant belief processing about a more chaotic world relevant to delusions. These opposing cortical-subcortical effects relate in part to genetic risk for schizophrenia, with analogous imbalances in neural processing of less expected versus familiar information patterns.

Cerebral Inefficient Activation in Schizophrenia Patients and Their Unaffected Parents during the N-Back Working Memory Task: A Family fMRI Study.

BACKGROUND: It has been suggested that working memory deficits is a core feature of symptomatology of schizophrenia, which can be detected in patients and their unaffected relatives. The impairment of working memory has been found related to the abnormal activity of human brain regions in many functional magnetic resonance imaging (fMRI) studies. This study investigated how brain region activation was altered in schizophrenia and how it was inherited independently from performance deficits. METHOD: The authors used fMRI method during N-back task to assess working memory related cortical activation in four groups (N = 20 in each group, matching task performance, age, gender and education): schizophrenic patients, their unaffected biological parents, young healthy controls for the patients and older healthy controls for their parents. RESULTS: Compared to healthy controls, patients showed an exaggerated response in the right dorsolateral prefrontal cortex (brodmann area [BA] 46) and bilateral ventrolateral prefrontal cortex, and had reduced activation in bilateral dorsolateral prefrontal cortex (BA 9). In the conjunction analysis, the effect of genetic risk (parents versus older control) shared significantly overlapped activation with effect of disease (patients versus young control) in the right middle frontal gyrus (BA 46) and left inferior parietal gyrus (BA 40). CONCLUSIONS: Physiological inefficiency of dorsal prefrontal cortex and compensation involvement of ventral prefrontal cortex in working memory function may one physiological characteristics of schizophrenia. And relatively inefficient activation in dorsolateral prefrontal cortex probably can be a promising intermediate phenotype for schizophrenia.