Publications by authors named "Shenton M"

Background: Clinically meaningful cognitive impairment has typically been defined as a single impaired test score, but this approach is prone to false-positive errors. Examining two test scores at a lower threshold (i.e.

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Background: Traumatic encephalopathy syndrome (TES) is the proposed clinical syndrome of chronic traumatic encephalopathy (CTE), a neurodegenerative disease associated with repetitive head impacts in contact/collision sports. A core clinical feature of TES is cognitive impairment, particularly in memory and executive functions. Cognitive intraindividual variability (IIV) is the extent of variability in neuropsychological test performance (i.

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Former American football players are at risk for developing traumatic encephalopathy syndrome (TES), the clinical disorder associated with neuropathologically diagnosed chronic traumatic encephalopathy (CTE). The objective of this study was to determine whether hyposmia is present in traumatic encephalopathy syndrome. The study included 119 former professional American football players, 60 former college football players, and 58 same-age asymptomatic unexposed men from the DIAGNOSE CTE Research Project.

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The Clinical High Risk (CHR) stage of psychosis is characterized by subthreshold symptoms of schizophrenia including negative symptoms, dysphoric mood, and functional deterioration. Hyperconnectivity of the default-mode network (DMN) has been observed in early schizophrenia, but the extent to which hyperconnectivity is present in CHR, and the extent to which such hyperconnectivity may underlie transdiagnostic symptoms, is not clear. As part of the Shanghai At-Risk for Psychosis (SHARP) program, resting-state fMRI data were collected from 251 young adults (158 CHR and 93 controls, M = 18.

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Soluble oxalate accumulates in rice leaves, and it causes mineral deficiency and urinary syndrome in livestock that consume the leaves. In our previous study, we found that the oxalate content was higher in the leaves of Koshihikari ( type cultivar) than in those of Takanari ( type cultivar). This difference was seen even when the two cultivars were grown under a high CO concentration, which inhibits oxalate synthesis via photorespiration, suggesting that the difference resulted from genetic factors rather than environmental factors.

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Background: Transcriptome-based prediction of complex phenotypes is a relatively new statistical method that links genetic variation to phenotypic variation. The selection of large-effect genes based on a priori biological knowledge is beneficial for predicting oligogenic traits; however, such a simple gene selection method is not applicable to polygenic traits because causal genes or large-effect loci are often unknown. Here, we used several gene-level features and tested whether it was possible to select a gene subset that resulted in better predictive ability than using all genes for predicting a polygenic trait.

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Article Synopsis
  • - Blood-based biomarkers are being explored to detect brain injuries from repetitive head impacts, specifically in former football players, by analyzing plasma levels of various proteins like tau and amyloid.
  • - A study involving 180 former football players and 60 control participants found that specific biomarkers (p-tau181 and p-tau231) were significantly elevated in the football players, indicating potential brain damage linked to their sport.
  • - The findings suggest that certain plasma proteins (p-tau, GFAP, NfL) could help in understanding and identifying neurological issues related to head impacts, with younger players showing more severe biomarker changes.
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Characterizing cortical plasticity becomes increasingly important for identifying compensatory mechanisms and structural reserve in the ageing population. While cortical thickness (CT) largely contributed to systems neuroscience, it incompletely informs about the underlying neuroplastic pathophysiology. In turn, microstructural characteristics may correspond to atrophy mechanisms in a more sensitive way.

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  • The study investigates the relationship between perivascular space (PVS) volume in the brain and lifetime exposure to repetitive head impacts (RHI) in individuals at risk for neurodegenerative diseases, particularly focusing on former American football players.
  • Conducted across four US study sites from 2016 to 2020, the research involved 224 participants, including 170 former football players and 54 control participants, with analyses exploring how PVS volume correlates with cognitive impairment.
  • Results showed that former football players exhibited larger PVS volumes compared to the control group, suggesting that RHI exposure could contribute to changes in brain structure associated with neurodegeneration.
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  • Exposure to repetitive head impacts (RHI) correlates with chronic traumatic encephalopathy (CTE), which can only be diagnosed after death; the study explores the presence of a cavum septum pellucidum (CSP) in living former football players to understand its relation to RHI and potential CTE.
  • The research involved 175 former players, both college and professional, and compared their CSP measurements to a control group without RHI exposure, assessing associations with cumulative head impact and traumatic encephalopathy syndrome (TES).
  • Results indicated that former players had significantly higher CSP presence and ratio compared to controls, with professional players exhibiting an even greater ratio; however, there was no notable link between CSP and TES or provisional
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  • The Human Connectome Project for Early Psychosis (HCP-EP) studies how the brain works in people who are starting to experience psychosis, which is when someone has trouble telling what's real and what's not.
  • They collected detailed information from 303 participants aged 16-35 across different hospitals in Massachusetts and Indiana.
  • The study aims to help researchers understand and compare different types of psychosis, and all the data is available for other scientists to use.
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  • The study investigates neurobehavioral dysregulation (NBD), which includes neuropsychiatric symptoms linked to repetitive head impacts, particularly in former contact sport athletes.
  • Through analyses involving questionnaires from 178 former football players, researchers identified four subconstructs of NBD: explosivity, emotional dyscontrol, impulsivity, and affective lability.
  • The results revealed four symptom profiles among participants, highlighting the complexity of NBD and serving as a basis for future research on its diagnostic criteria and neurobiological aspects.
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Background: Neurocognitive impairment is a well-known phenomenon in schizophrenia that begins prior to psychosis onset. Connectome-wide association studies have inconsistently linked cognitive performance to resting-state functional magnetic resonance imaging. We hypothesized that a carefully selected cognitive instrument and refined population would allow identification of reliable brain-behavior associations with connectome-wide association studies.

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Background: Military veterans with posttraumatic stress disorder (PTSD) commonly experience posttraumatic guilt. Guilt over commission or omission evolves when responsibility is assumed for an unfortunate outcome (e.g.

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  • Many veterans experience intimate partner violence (IPV) and risk factors for this include things like combat experiences, PTSD, and depression.
  • The study looked at 49 male veterans to see if problems in their brain, specifically in the limbic system, relate to their likelihood of committing IPV.
  • Results showed that veterans with PTSD, depression, or other issues were more likely to engage in IPV, especially if they had more stress from war.
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Recent studies show that accelerated cortical gray matter (GM) volume reduction seen in anatomical MRI can help distinguish between individuals at clinical high risk (CHR) for psychosis who will develop psychosis and those who will not. This reduction is suggested to represent atypical developmental or degenerative changes accompanying an accumulation of microstructural changes, such as decreased spine density and dendritic arborization. Detecting the microstructural sources of these changes before they accumulate into volume loss is crucial.

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Enlarged lateral ventricle (LV) volume and decreased volume in the corpus callosum (CC) are hallmarks of schizophrenia (SZ). We previously showed an inverse correlation between LV and CC volumes in SZ, with global functioning decreasing with increased LV volume. This study investigates the relationship between LV volume, CC abnormalities, and the microRNA MIR137 and its regulated genes in SZ, because of MIR137's essential role in neurodevelopment.

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  • * A study evaluated brain structures using MRI in 170 former football players and 54 controls, assessing regions associated with CTE pathology, revealing significant reductions in cortical thickness and volume in players compared to controls.
  • * Former professional players showed more pronounced brain changes than former college players, specifically in areas like the hippocampus and amygdala, indicating that exposure to head impacts has lasting effects on brain structure.
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Decades of psychosis research highlight the prevalence and the clinical significance of negative emotions, such as fear and anxiety. Translational evidence demonstrates the pivotal role of the amygdala in fear and anxiety. However, most of these approaches have used hypothesis-driven analyses with predefined regions of interest.

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Background: Mild traumatic brain injury (mTBI) is common in children. Long-term cognitive and behavioral outcomes as well as underlying structural brain alterations following pediatric mTBI have yet to be determined. In addition, the effect of age-at-injury on long-term outcomes is largely unknown.

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Background: Psychomotor disturbances are observed across psychiatric disorders and often manifest as psychomotor slowing, agitation, disorganized behavior, or catatonia. Psychomotor function includes both cognitive and motor components, but the neural circuits driving these subprocesses and how they relate to symptoms have remained elusive for centuries.

Methods: We analyzed data from the HCP-EP (Human Connectome Project for Early Psychosis), a multisite study of 125 participants with early psychosis and 58 healthy participants with resting-state functional magnetic resonance imaging and clinical characterization.

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This article describes the rationale, aims, and methodology of the Accelerating Medicines Partnership® Schizophrenia (AMP® SCZ). This is the largest international collaboration to date that will develop algorithms to predict trajectories and outcomes of individuals at clinical high risk (CHR) for psychosis and to advance the development and use of novel pharmacological interventions for CHR individuals. We present a description of the participating research networks and the data processing analysis and coordination center, their processes for data harmonization across 43 sites from 13 participating countries (recruitment across North America, Australia, Europe, Asia, and South America), data flow and quality assessment processes, data analyses, and the transfer of data to the National Institute of Mental Health (NIMH) Data Archive (NDA) for use by the research community.

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Background And Objectives: Obstructive sleep apnea (SA) is common in older men and a contributor to negative cognitive, psychiatric, and brain health outcomes. Little is known about SA in those who played contact sports and are at increased risk of neurodegenerative disease(s) and other neuropathologies associated with repetitive head impacts (RHI). In this study, we investigated the frequency of diagnosed and witnessed SA and its contribution to clinical symptoms and tau pathology using PET imaging among male former college and former professional American football players.

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Article Synopsis
  • Traumatic encephalopathy syndrome (TES) is linked to chronic traumatic encephalopathy (CTE) and is characterized by neurobehavioral dysregulation (NBD), impacting emotional and behavioral regulation in individuals exposed to repetitive head impacts, like former American football players.
  • The study involved 104 former players diagnosed with NBD, 76 without the diagnosis, and 55 unexposed individuals, using self-report measures to assess NBD symptoms and cerebrospinal fluid (CSF) biomarkers associated with inflammation.
  • Results indicated that levels of the pro-inflammatory cytokine IL-6 were significantly higher in former players, suggesting a connection between these inflammation markers and NBD symptoms linked to past head impacts.
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On average, healthy older adults prefer positive over neutral or negative stimuli. This positivity bias is related to memory and attention processes and is linked to the function and structure of several interconnected brain areas. However, the relationship between the positivity bias and white matter integrity remains elusive.

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