View clinical trials related to Neuroimaging.
Filter by:This study aims to assess the diagnostic performance of a new fast MRI sequence named Neuromix compared to routine clinical MRI for brain tumor in pediatric patients
The main purpose of this study is to gain a better understanding of the distinct mental states and physical reactions that can arise during a psychedelic experience. By repeatedly assessing the same participants in an MRI while under the effects of psilocybin, the investigators want to identify reliable brain and body reactions arising during these psychedelic experiences. It is hoped that this will provide an insight to inspire future research on psilocybin and related psychedelics as well as inform on their therapeutic action. This study will involve up to 12 healthy volunteers with previous psychedelic experience. Participants in this study will be given four doses of psilocybin, with breaks of at least seven days in between dosing visits. The first dosing visit will feature a 10 mg dose of psilocybin, which can be considerate a low to moderate dose, whereas the remaining three dosing visits will feature 25 mg psilocybin, a high dose that is consistent with the dosage chosen for several modern clinical trials with psilocybin. From the initial in-person screening visit to the final follow-up, participants will be in this study for approximately 6-12 weeks and visit the research site 5 times. The first visit will be an in-person screening visit, during which the investigators will assess participants' eligibility to be enrolled. There will be 4 subsequent visits to the scan center for dosing and magnetic resonance imaging (MRI) scanning, and there will be a final remote follow up. Each of the four dosing visits will include four periods of lying within the MRI scanner for scanning, each of these 'in-scanner' sessions will last for ~ 45 minutes. Actual scans, which are also called 'runs' last for ~ 12 mins. During these 'runs', the investigators will ask participants two brief questions about how positive or negative their current experience is every 100 seconds. They will be able to record their answers using a button box which they will be operating with their hand. One day after each dosing visit, the investigators will schedule a phone call with the participant to check how they are doing and perform an informal interview focused on their experience while under the effects of psilocybin.
Cognitive impairment is well established in people with psychosis and is associated with cannabis use. The current study will investigate the neurobiological basis of cognitive change associated with 28-days of cannabis abstinence in people with psychosis and non-psychiatric controls with cannabis use. Participants will be randomized to a cannabis abstinent group or a non-abstinent control group and will undergo magnetic resonance imaging at baseline and following 28-days of abstinence. This study will help characterize the neuropathophysiological processes underlying cognitive dysfunction associated with cannabis use and its recovery which may guide the development of novel interventions for problematic cannabis use.
Schizophrenia is a heritable complex phenotype whose symptoms can be clustered into three domains: positive symptoms, negative symptoms and cognitive impairments. Constellations of negative symptoms in SCZ are composed of diminished motivation and pleasure, such as asociality, anhedonia, and avolition, or diminished expressivity such as blunted affect and alogia. Negative symptoms are associated with decreased quality of life and poor functional outcomes. Although antipsychotics are generally effective on positive symptoms, they are poorly effective on negative symptoms Currently, there are no licensed targeted medications for negative symptoms. In view of these problems, considerable interest in identifying new treatment targets for negative symptoms has grown over the past decade. Despite intense efforts in brain imaging that have opened new opportunities for addressing these issues, the neurobiological mechanism of negative symptoms remains unclear. Structural brain measures from magnetic resonance imaging (MRI) are highly heritable and representatively have high reproducibility and low measurement error. Prior neuroimaging researches have consistently shown neuroanatomical abnormalities in the brains of individuals with SCZ, with the most robust and consistent group-level structural differences in widespread reduced volumes of hippocampal thalamus, amygdala and nucleus accumbens. SCZ have been associated with widespread structural brain abnormalities, but results from neuroimaging studies have been inconsistent.
The purpose of this study is to explore the long-term consequences of neuroimaging and perceived cognitive dysfunction in obstetrics posterior reversible encephalopathy syndrome.
The 2020 NIMH Strategic Plan for Research calls for investigations targeting neurobiology of mental illness across the lifespan. Growing evidence suggests that lifespan neurobiology of schizophrenia (SZ) incorporates two distinct dimensions: aging and disease course. However, their clinical correlates, associated biomarker trajectories, and implications for treatment are unknown. This study will investigate differential aspects of SZ neurobiology captured by aging and disease course, in order to develop specific biomarkers which may offer actionable targets for SZ stage-dependent intervention. The study is predicated on a novel mechanistic Model of SZ Trajectories across the Adult Lifespan, positing distinct biological fingerprints within the anterior limbic system for aging and disease course in SZ: (1) alterations in the circuit's function and structure that occur earlier in the lifespan and are larger in magnitude than the alterations expected with normal aging (accelerated aging dimension); and (2) regionally-specific anterior limbic "hyperactivity" in early SZ, with a subsequent transformation into "hypoactivity" in advanced SZ (disease course dimension). In a sample of SZ and matched healthy controls (n=168, 84/group) aged 18-75 years the investigators will ascertain a broad panel of biomarkers [via multimodal brain imaging: optimized 1H-MRS, high-resolution task-based fMRI, perfusion (Vascular Space Occupancy) and structural MRI], along with comprehensive cognitive and clinical assessments. All measures will be acquired at baseline and repeated at 2-year longitudinal follow-up. Using cutting-edge computational approaches, the study will examine (i) effects of aging and SZ course on anterior limbic system biomarkers; (ii) lifespan trajectories for different biomarkers; (iii) patterns of limbic system biomarkers in age- and SZ course-based subgroups (e.g., Younger vs. Older, Early-Course vs. Advanced SZ), as well as in data-driven subgroups (e.g., those with vs. without accelerated aging profiles); and (iv) associations between biomarkers and cognitive and clinical outcomes. This research will advance the field by providing novel biomarkers that capture unique neurobiological contributions of aging and disease course in SZ, and will motivate future studies on SZ mechanisms across the lifespan and development of precision treatments.
This study applies a hypothesis-driven approach to examine the effects of chronic marijuana use on HIV-associated inflammation and its subsequent impacts on central nervous system function, with the goal of identifying the mechanisms through which cannabinoids modulate neurological disorders and other comorbidities in persons with HIV.
This study aimed to discuss the neuroimaging findings and indications, epidemiological data, laboratory values, and the relationship of these variables with mortality in patients with COVID-19.
The incidence of AD dementia is increasing due to the aging population, putting a heavy burden on our society and economics. Exploring the mechanisms underlying SCD due to preclinical AD has scientific and clinical significance. However, it is challenging to construct and validate the preclinical diagnosis model of AD with fused multimodel information across culture/race. From the cooperation during the past five years, we have established cohorts by synchronized assessment, achieved consensus on SCD features extraction and made a breakthrough in the application of multiple parameter MRI with German collaborators. Therefore, in this project, SCD with and without amyloid pathology will be compared by clinical and cognitive data, genetics, blood and MRI biomarkers between the German and Chinese. Key features will be extracted and specific characteristics of SCD due to preclinical AD as well as risk factors for conversion between two countries will be clarified. Then the diagnosis model of preclinical AD in SCD will be established across culture/race based on radiogenomics, which will improve the current diagnostic system of AD. Through this project, the value of SCD in the etiologic, anatomical and quantitative diagnosis of preclinical AD will be identified to improve sensitivity and specificity of preclinical AD diagnosis in clinical practice.
This within-subject, double blind, randomized controlled study will investigate the effects of a widely used benzodiazepine (BZD), lorazepam, on various neuroimaging measures. The investigators will be assessing the relationship of lorazepam to resting state functional connectivity and other neuroimaging measures. Specifically, the investigators will be using a pre-identified metric, the striatal connectivity index (SCI), (Sarpal et al. 2015, 2016), a prognostic biomarker of treatment response assessing the connectivity between regions of the striatum and the cortex. The investigators hypothesize that lorazepam administration will be associated with greater SCI values compared with placebo administration; consistent with previous work suggesting short-acting benzodiazepines increase functional connectivity across brain networks.