Biol Psychiatry Cogn Neurosci Neuroimaging
December 2024
Background: Phenomenological psychopathologists have recently highlighted how people with delusions experience multiple realities (delusional and non-delusional) and have suggested this double bookkeeping cannot be explained via predictive processing. Here, we present data from Kamin blocking and extinction learning that show how predictive processing might, in principle, explain a pervasive sense of dual reality.
Methods: This cross-sectional study involved three participant groups: patients with schizophrenia (SZ; n=42), healthy participants with elevated esoteric beliefs (EEB; clairaudient psychics; n=31), and heathy controls (with neither illness nor significant delusional ideation, n=62).
Background: Among people with schizophrenia (PSZ), reduced mismatch negativity (MMN) is conceptualized as evidence of disrupted prediction error signaling that underlies positive symptoms. However, this conceptualization has been challenged by observations that MMN and positive symptoms are often uncorrelated. In the current study, we tested the hypothesis that reduced MMN is associated with the presence of hallucinations and delusions specifically rather than the presence of a psychiatric illness.
View Article and Find Full Text PDFBiol Psychiatry Cogn Neurosci Neuroimaging
September 2024
Background: People with schizophrenia (PSZ) show impaired accuracy in spatial working memory (sWM), which is thought to reflect abnormalities in the sustained firing of feature selective neurons that are critical for successful encoding and maintenance processes. Recent research has documented a new source of variance in the accuracy of sWM: In healthy adults, sWM representations are unconsciously biased by previous trials such that current-trial responses are attracted to previous-trial responses (serial dependence). This opens a new window to examine how schizophrenia impacts both the sustained neural firing representing the current-trial target and the longer-term synaptic plasticity that stores previous-trial information.
View Article and Find Full Text PDFThe objective of the study was to evaluate tibial cartilage thickness (TCT), T1ρ and T2 values within both loaded and baseline configurations in a cadaveric knee model using a 3D bone based tibial coordinate system. Ten intact cadaveric knees were mounted into an magnetic resonance imaging (MRI) compatible loading device. Morphologic and quantitative MRI (qMRI) images were acquired with the knee in a baseline configuration and after application of 50% body weight.
View Article and Find Full Text PDFJ Clin Monit Comput
July 2024
Dexmedetomidine decreases heart rate (HR) and increases high frequency (HF) component of HR variability (HRV). Analgesia Nociception Index (ANI) measures nociception by analyzing the influence of respiration on HF component of HRV while surgical pleth index (SPI) derives this information from photoplethymographic signals of finger arterioles. Therefore, during administration of dexmedetomidine, reliability of ANI may vary.
View Article and Find Full Text PDFBackground: There is limited literature investigating the catecholamine levels in patients with paroxysmal sympathetic hyperactivity (PSH) after traumatic brain injury (TBI). The primary objective of this study was to correlate the severity of PSH (assessed using the PSH-Assessment measure [AM]) with plasma catecholamine levels at a resting state.
Methods: In this prospective case-control study, blood samples for epinephrine and norepinephrine estimation were obtained at rest on three consecutive days, only for 'cases' of PSH after severe TBI (s-TBI) and for control patients (matched for age, gender, and Glasgow coma scale [GCS].
Aberrant alterations in any of the two dimensions of consciousness, namely awareness and arousal, can lead to the emergence of disorders of consciousness (DOC). The development of DOC may arise from more severe or targeted lesions in the brain, resulting in widespread functional abnormalities. However, when it comes to classifying patients with disorders of consciousness, particularly utilizing resting-state electroencephalogram (EEG) signals through machine learning methods, several challenges surface.
View Article and Find Full Text PDFAsian J Psychiatr
October 2023
Objectives: Modified ECT is routinely conducted using face mask (FM) and bag ventilation technique. Trans-nasal Humidified Rapid Insufflation Ventilatory Exchange (THRIVE) is a novel hands-free insufflation technique that provides oxygenation and prolongs apnoea time. There is limited literature comparing the two techniques.
View Article and Find Full Text PDFBackground And Aims: Patients with traumatic brain injury (TBI) frequently require emergency surgery. There is a paucity of literature with regard to anesthetic requirements in these patients. The aim of the study was to compare the dose of propofol required for induction of anesthesia in patients with different grades of TBI.
View Article and Find Full Text PDFMartial arts are various systems of combat skills encompassing striking and grappling. Many styles have evolved into modern sports, and some have been included in the Olympics. The physicality of these can predispose practitioners to musculoskeletal injuries, such as anterior cruciate ligament ruptures; patellar, shoulder, or elbow instabilities; extremity fractures; and hand and spine injuries, which have been studied both clinically and biomechanically.
View Article and Find Full Text PDFBiol Psychiatry Cogn Neurosci Neuroimaging
December 2023
Background: Impairments in working memory (WM) have been well documented in people with schizophrenia (PSZ). However, these quantitative WM impairments can often be explained by nonspecific factors, such as impaired goal maintenance. Here, we used a spatial orientation delayed response task to explore a qualitative difference in WM dynamics between PSZ and healthy control participants (HCs).
View Article and Find Full Text PDFBackground And Hypotheses: Auditory verbal hallucinations (AVH) are central features of schizophrenia (SZ). However, AVH also occur in a small percentage of the general population who do not have a need for care, termed nonclinical voice hearers (NCVH). We sought to determine the degree to which the experience of AVH was similar in NCVH and in people with schizophrenia (PSZ) and evaluate the degree to which NCVH shared other features of SZ such as delusional beliefs, cognitive impairment, and negative symptoms.
View Article and Find Full Text PDFBackground: Sustained attention and vigilance impairments are well documented in people with schizophrenia (PSZ). The processes implicated in this impairment remain unclear. Here we investigated whether vigilance performance varied as a function of working memory load, and also examined the role of attentional lapsing that might arise from a loss of task set resulting in mind wandering.
View Article and Find Full Text PDFObjectives: Moyamoya disease (MMD) leads to frequent ischemic/hemorrhagic manifestations. Our aim was to compare findings of arterial spin labeling (ASL) with dynamic susceptibility contrast (DSC) perfusion in patients of MMD.
Materials And Methods: Patients diagnosed as MMD underwent magnetic resonance imaging with ASL and DSC perfusion sequences.
Background: Impairments in working memory(WM) have been well-documented in people with schizophrenia(PSZ). However, these WM impairments can often be explained by nonspecific factors, such as impaired goal maintenance. Here, we used a spatial orientation delayed-response task to explore a difference in WM dynamics between PSZ and healthy control subjects(HCS).
View Article and Find Full Text PDFImportance: Distinguishing delusions and hallucinations from unusual beliefs and experiences has proven challenging.
Observations: The advent of neural network and generative modeling approaches to big data offers a challenge and an opportunity; healthy individuals with unusual beliefs and experiences who are not ill may raise false alarms and serve as adversarial examples to such networks.
Conclusions And Relevance: Explicitly training predictive models with adversarial examples should provide clearer focus on the features most relevant to casehood, which will empower clinical research and ultimately diagnosis and treatment.
Background: Delayed neurocognitive recovery (DNR) is commonly seen in patients in the postoperative period. Literature has shown that monitoring cerebral desaturation intraoperatively can predict the development of DNR in elderly patients undergoing surgery in prone position. This prospective observational study was conducted in patients of all ages, with the primary objective to determine the incidence of DNR and its correlation with cerebral oximetry.
View Article and Find Full Text PDFBackground And Aims: Surgical Pleth Index (SPI) provides an objective assessment of nociception - anti-nociception balance but is influenced by multiple confounders. The effect of change of position on SPI, has not been studied extensively. The aim of the study was to observe the effect of prone positioning on SPI and its correlation with hemodynamic variables, in patients undergoing lumbar and thoracic spine surgery.
View Article and Find Full Text PDFKnowing which neurons are active during behavior is a crucial step toward understanding how nervous systems work. Neuronal activation is generally accompanied by an increase in intracellular calcium levels. Therefore, intracellular calcium levels are widely used as a proxy for neuronal activity.
View Article and Find Full Text PDFCold Spring Harb Protoc
January 2023
Calcium-dependent nuclear import of LexA (CaLexA) and transcriptional reporter of intracellular calcium (TRIC) are transcription-based genetically encoded calcium indicators (transcriptional GECIs). When expressed in neurons, CaLexA and TRIC report neuronal activity by converting intracellular calcium levels into transcription activities and, subsequently, reporter gene expression. CaLexA and TRIC have been used successfully in many studies to label neurons associated with particular behaviors, regulated by internal states, or evoked by specific sensory inputs.
View Article and Find Full Text PDFBackground And Aims: Analgesia Nociception Index (ANI) and Surgical Pleth Index (SPI) are measures of nociception-antinociception balance during general anaesthesia. The validity of these two monitors during autonomic changes brought about by intraoperative blood loss and noradrenaline infusion has not been studied earlier. The primary objective of the study was to determine the effect of bleeding on ANI and SPI.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
March 2022
SignificanceThe adult mushroom body (MB) is one of the most extensively studied neural circuits. However, how its circuit organization is established during development is unclear. In this study, we provide an initial characterization of the assembly process of the extrinsic neurons (dopaminergic neurons and MB output neurons) that target the vertical MB lobes.
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