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1.
Neuroimage ; 239: 118313, 2021 10 01.
Article in English | MEDLINE | ID: mdl-34175425

ABSTRACT

Growing evidence shows that theta-band (4-7 Hz) activity in the auditory cortex phase-locks to rhythms of overt speech. Does theta activity also encode the rhythmic dynamics of inner speech? Previous research established that silent reading of direct speech quotes (e.g., Mary said: "This dress is lovely!") elicits more vivid inner speech than indirect speech quotes (e.g., Mary said that the dress was lovely). As we cannot directly track the phase alignment between theta activity and inner speech over time, we used EEG to measure the brain's phase-locked responses to the onset of speech quote reading. We found that direct (vs. indirect) quote reading was associated with increased theta phase synchrony over trials at 250-500 ms post-reading onset, with sources of the evoked activity estimated in the speech processing network. An eye-tracking control experiment confirmed that increased theta phase synchrony in direct quote reading was not driven by eye movement patterns, and more likely reflects synchronous phase resetting at the onset of inner speech. These findings suggest a functional role of theta phase modulation in reading-induced inner speech.


Subject(s)
Auditory Cortex/physiology , Electroencephalography , Electrooculography , Eye Movements/physiology , Mental Processes/physiology , Reading , Speech/physiology , Theta Rhythm/physiology , Adult , Female , Humans , Male , Time Factors , Young Adult
2.
Clin Gastroenterol Hepatol ; 19(6): 1282-1284, 2021 06.
Article in English | MEDLINE | ID: mdl-32454259

ABSTRACT

Percutaneous transhepatic biliary drainage (PTBD) and endoscopic retrograde cholangiopancreatography (ERCP) are widely accepted but competing approaches for the management of malignant obstruction at the hilum of the liver. ERCP is favored in the United States on the basis of high success rates for non-hilar indications, the perceived safety and superior tissue sampling capability of ERCP relative to PTBD, and the avoidance of external drains that are undesirable to patients. A recent randomized controlled trial (RCT) comparing the 2 modalities in patients with resectable hilar cholangiocarcinoma was terminated prematurely because of higher mortality in the PTBD group.1 In contrast, most observational data suggest that PTBD is superior for achieving complete drainage.2-6 Because the preferred procedure remains uncertain, we aimed to compare PTBD and ERCP as the primary intervention in patients with cholestasis due to malignant hilar obstruction (MHO).


Subject(s)
Bile Duct Neoplasms , Cholestasis , Bile Duct Neoplasms/complications , Bile Ducts, Intrahepatic , Cholangiopancreatography, Endoscopic Retrograde , Cholestasis/surgery , Drainage , Endosonography , Humans
3.
Clin Gastroenterol Hepatol ; 19(7): 1355-1365.e4, 2021 Jul.
Article in English | MEDLINE | ID: mdl-33010411

ABSTRACT

BACKGROUND & AIMS: The prevalence and significance of digestive manifestations in coronavirus disease 2019 (COVID-19) remain uncertain. We aimed to assess the prevalence, spectrum, severity, and significance of digestive manifestations in patients hospitalized with COVID-19. METHODS: Consecutive patients hospitalized with COVID-19 were identified across a geographically diverse alliance of medical centers in North America. Data pertaining to baseline characteristics, symptomatology, laboratory assessment, imaging, and endoscopic findings from the time of symptom onset until discharge or death were abstracted manually from electronic health records to characterize the prevalence, spectrum, and severity of digestive manifestations. Regression analyses were performed to evaluate the association between digestive manifestations and severe outcomes related to COVID-19. RESULTS: A total of 1992 patients across 36 centers met eligibility criteria and were included. Overall, 53% of patients experienced at least 1 gastrointestinal symptom at any time during their illness, most commonly diarrhea (34%), nausea (27%), vomiting (16%), and abdominal pain (11%). In 74% of cases, gastrointestinal symptoms were judged to be mild. In total, 35% of patients developed an abnormal alanine aminotransferase or total bilirubin level; these were increased to less than 5 times the upper limit of normal in 77% of cases. After adjusting for potential confounders, the presence of gastrointestinal symptoms at any time (odds ratio, 0.93; 95% CI, 0.76-1.15) or liver test abnormalities on admission (odds ratio, 1.31; 95% CI, 0.80-2.12) were not associated independently with mechanical ventilation or death. CONCLUSIONS: Among patients hospitalized with COVID-19, gastrointestinal symptoms and liver test abnormalities were common, but the majority were mild and their presence was not associated with a more severe clinical course.


Subject(s)
COVID-19 , Gastrointestinal Diseases/virology , Adolescent , Adult , Aged , Aged, 80 and over , COVID-19/complications , Female , Humans , Male , Middle Aged , North America , Young Adult
4.
Epilepsia ; 62(2): 492-503, 2021 02.
Article in English | MEDLINE | ID: mdl-33501642

ABSTRACT

OBJECTIVE: The study aim was to compare interictal encephalographic (EEG) functional network topology between people with well-controlled idiopathic generalized epilepsy (WC-IGE) and drug-resistant IGE (DR-IGE). METHODS: Nineteen participants with WC-IGE, 18 with DR-IGE, and 20 controls underwent a resting state, 64-channel EEG. An artifact-free epoch was bandpass filtered into the frequency range of high and low extended alpha. Weighted functional connectivity matrices were calculated. Mean degree, degree distribution variance, characteristic path length (L), clustering coefficient, small world index (SWI), and betweenness centrality were measured. A Kruskal-Wallis H-test assessed effects across groups. Where significant differences were found, Bonferroni-corrected Mann-Whitney pairwise comparisons were calculated. RESULTS: In the low alpha band (6-9 Hz), there was a significant difference in L at the three-group level (p < .0001). This was lower in controls than both WC-IGE and DR-IGE (p < .0001 for both), with no difference in L between WC-IGE and DR-IGE. Mean degree (p = .031), degree distribution variance (p = .032), and SWI (p = .023) differed across the three groups in the high alpha band (10-12 Hz). Mean degree and degree distribution variance were lower in WC-IGE than controls (p = .029 for both), and SWI was higher in WC-IGE compared with controls (p = .038), with no differences in other pairwise comparisons. SIGNIFICANCE: IGE network topology is more regular in the low alpha frequency band, potentially reflecting a more vulnerable structure. WC-IGE network topology is different from controls in the high alpha band. This may reflect drug-induced network changes that have stabilized the WC-IGE network by rendering it less likely to synchronize. These results are of potential importance in advancing the understanding of mechanisms of epilepsy drug resistance and as a possible basis for a biomarker of DR-IGE.


Subject(s)
Brain/physiopathology , Drug Resistant Epilepsy/physiopathology , Epilepsy, Generalized/physiopathology , Adolescent , Adult , Anticonvulsants/therapeutic use , Drug Resistant Epilepsy/drug therapy , Electroencephalography , Epilepsy, Generalized/drug therapy , Female , Humans , Male , Middle Aged , Neural Pathways , Young Adult
5.
Gastrointest Endosc ; 93(6): 1207-1214.e2, 2021 06.
Article in English | MEDLINE | ID: mdl-33832739

ABSTRACT

BACKGROUND AND AIMS: The American Society for Gastrointestinal Endoscopy (ASGE) advanced endoscopy fellowship (AEF) match offers a structured application process for AEF training in the United States. Our aim was to describe recent trends in AEF match, trainee experience, and postfellowship employment. METHODS: ASGE AEF match data from 2012 to 2020 were reviewed. Online surveys were sent to advanced endoscopy trainees in 2019 and 2020 to explore their perceptions about AEF training and postfellowship jobs. RESULTS: Data for 2020 showed 19% of matched applicants were women, 55% foreign medical graduates, and 17.5% U.S. visa holders. The number of AEF match applicants increased by 15.6% (90 in 2012 to 104 in 2020) and number of AEF programs increased by 23.5% (51 in 2012 to 63 in 2020). The average applicant match rate was 57% (range, 52.8%-60.6%) and position match rate 87.9% (range, 79.1%-94.6%). Ninety-one percent of trainees (n = 58) rated the quality of their training as very good/excellent; 75% of trainees participated in >300 ERCPs and 64.1% in >300 EUS cases. Seventy percent of trainees reported that advanced endoscopic procedures comprised ≤50% of their procedure volume in their first job, and 71.9% believed it was not easy to find a job after fellowship; however, 97% believed they would make the same decision to pursue AEF training again. CONCLUSIONS: There has been a steady increase in the number of advanced endoscopy applicants and training positions over recent years. Most graduating fellows reported 50% or less of their upcoming clinical practice would involve advanced endoscopic procedures. Future studies are needed to further clarify employment opportunities and personnel needs for advanced endoscopists.


Subject(s)
Fellowships and Scholarships , Internship and Residency , Education, Medical, Graduate , Employment , Endoscopy, Gastrointestinal , Female , Humans , Male , United States
6.
Gastrointest Endosc ; 93(4): 914-923, 2021 04.
Article in English | MEDLINE | ID: mdl-32739484

ABSTRACT

BACKGROUND AND AIMS: The accurate measurement of technical skill in ERCP is essential for endoscopic training, quality assurance, and coaching of this procedure. Hypothesizing that technical skill can be measured by analysis of ERCP videos, we aimed to develop and validate a video-based ERCP skill assessment tool. METHODS: Based on review of procedural videos, the task of ERCP was deconstructed into its basic components by an expert panel that developed an initial version of the Bethesda ERCP Skill Assessment Tool (BESAT). Subsequently, 2 modified Delphi panels and 3 validation exercises were conducted with the goal of iteratively refining the tool. Fully crossed generalizability studies investigated the contributions of assessors, ERCP performance, and technical elements to reliability. RESULTS: Twenty-nine technical elements were initially generated from task deconstruction. Ultimately, after iterative refinement, the tool comprised 6 technical elements and 11 subelements. The developmental process achieved consistent improvements in the performance characteristics of the tool with every iteration. For the most recent version of the tool, BESAT-v4, the generalizability coefficient (a reliability index) was .67. Most variance in BESAT scores (43.55%) was attributed to differences in endoscopists' skill, indicating that the tool can reliably differentiate between endoscopists based on video analysis. CONCLUSIONS: Video-based assessment of ERCP skill appears to be feasible with a novel instrument that demonstrates favorable validity evidence. Future steps include determining whether the tool can discriminate between endoscopists of varying experience levels and predict important outcomes in clinical practice.


Subject(s)
Cholangiopancreatography, Endoscopic Retrograde , Clinical Competence , Humans , Reproducibility of Results
7.
Am J Gastroenterol ; 115(3): 322-339, 2020 03.
Article in English | MEDLINE | ID: mdl-32022720

ABSTRACT

Chronic pancreatitis (CP) is historically defined as an irreversible inflammatory condition of the pancreas leading to varying degrees of exocrine and endocrine dysfunction. Recently however, the paradigm for the diagnosis has changed in that it breaks with the traditional clinicopathologic-based definition of disease, focusing instead on diagnosing the underlying pathologic process early in the disease course and managing the syndrome more holistically to change the natural course of disease and minimize adverse disease effects. Currently, the most accepted mechanistically derived definition of CP is a pathologic fibroinflammatory syndrome of the pancreas in individuals with genetic, environmental, and/or other risk factors who develop persistent pathologic responses to parenchymal injury or stress. The most common symptom of CP is abdominal pain, with other symptoms such as exocrine pancreatic insufficiency and diabetes developing at highly variable rates. CP is most commonly caused by toxins such as alcohol or tobacco use, genetic polymorphisms, and recurrent attacks of acute pancreatitis, although no history of acute pancreatitis is seen in many patients. Diagnosis is made usually on cross-sectional imaging, with modalities such as endoscopic ultrasonography and pancreatic function tests playing a secondary role. Total pancreatectomy represents the only known cure for CP, although difficulty in patient selection and the complications inherent to this intervention make it usually an unattractive option. This guideline will provide an evidence-based practical approach to the diagnosis and management of CP for the general gastroenterologist.


Subject(s)
Pancreatitis, Chronic , Clinical Decision-Making/methods , Gastroenterology/methods , Gastroenterology/standards , Humans , Pancreatectomy , Pancreatitis, Chronic/complications , Pancreatitis, Chronic/diagnosis , Pancreatitis, Chronic/etiology , Pancreatitis, Chronic/therapy , Patient Selection
8.
Epilepsy Behav ; 112: 107427, 2020 11.
Article in English | MEDLINE | ID: mdl-32949965

ABSTRACT

INTRODUCTION: Idiopathic generalized epilepsies (IGE) are characterized by generalized interictal epileptiform discharges (IEDs) on a normal background electroencephalography (EEG). However, the yield of IEDs can be low. Approximately 20% of patients with IGE fail to achieve seizure control with antiepileptic drug (AED) treatment. Currently, there are no reliable prognostic markers for early identification of drug-resistant epilepsy (DRE). We examined spectral power of the interictal EEG in patients with IGE and healthy controls, to identify potential diagnostic and prognostic biomarkers of IGE. METHODS: A 64-channel EEG was recorded under standard conditions in patients with well-controlled IGE (WC-IGE, n = 19), drug-resistant IGE (DR-IGE, n = 18), and age-matched controls (n = 20). After preprocessing, fast Fourier transform was performed to obtain 1D frequency spectra for each EEG channel. The 1D spectra (averaged over channels) and 2D topographic maps (averaged over canonical frequency bands) were computed for each participant. Power spectra in the 3 cohorts were compared using one-way analysis of variance (ANOVA), and power spectra images were compared using T-contrast tests. A post hoc analysis compared peak alpha power between the groups. RESULTS: Compared with controls, participants with IGE had higher interictal EEG spectral power in the delta band in the midline central region, in the theta band in the midline, in the beta band over the left hemisphere, and in the gamma band over right hemisphere and left central regions. There were no differences in spectral power between cohorts with WC-IGE and DR-IGE. Peak alpha power was lower in WC-IGE and DR-IGE than controls. CONCLUSIONS: Electroencephalography spectral power analysis could form part of a clinically useful diagnostic biomarker for IGE; however, it did not correlate with response to AED in this study.


Subject(s)
Epilepsy, Generalized , Anticonvulsants/therapeutic use , Electroencephalography , Epilepsy, Generalized/diagnosis , Epilepsy, Generalized/drug therapy , Humans , Prognosis , Seizures/drug therapy
9.
Epilepsy Behav ; 106: 107013, 2020 05.
Article in English | MEDLINE | ID: mdl-32193094

ABSTRACT

The evaluation of the role of anomalous neuronal networks in epilepsy using a graph theoretical approach is of growing research interest. There is currently no consensus on optimal methods for performing network analysis, and it is possible that variations in study methodology account for diverging findings. This review focuses on global functional and structural interictal network characteristics in people with idiopathic generalized epilepsy (IGE) with the aim of appraising the methodological approaches used and assessing for meaningful consensus. Thirteen studies were included in the review. Data were heterogenous and not suitable for meta-analysis. Overall, there is a suggestion that the cerebral neuronal networks of people with IGE have different global structural and functional characteristics to people without epilepsy. However, the nature of the aberrations is inconsistent with some studies demonstrating a more regular network configuration in IGE, and some, a more random topology. There is greater consistency when different data modalities and connectivity subtypes are compared separately, with a tendency towards increased small-worldness of networks in functional electroencephalography/magnetoencephalography (EEG/MEG) studies and decreased small-worldness of networks in structural studies. Prominent variation in study design at all stages is likely to have contributed to differences in study outcomes. Despite increasing literature surrounding neuronal network analysis, systematic methodological studies are lacking. Absence of consensus in this area significantly limits comparison of results from different studies, and the ability to draw firm conclusions about network characteristics in IGE.


Subject(s)
Brain/diagnostic imaging , Brain/physiopathology , Epilepsy, Generalized/diagnostic imaging , Epilepsy, Generalized/physiopathology , Nerve Net/diagnostic imaging , Nerve Net/physiopathology , Brain Mapping/methods , Electroencephalography/methods , Female , Humans , Magnetic Resonance Imaging/methods , Magnetoencephalography/methods , Male , Models, Theoretical
10.
Behav Brain Sci ; 42: e289, 2020 01 03.
Article in English | MEDLINE | ID: mdl-31896359

ABSTRACT

We argue that while the proposed memory model by Bastin et al. can explain familiarity-based memory judgements through the interaction of a core representation system and an attribution system, recollection-based memory judgements are not based on non-mnemonic signals being attributed to memory.


Subject(s)
Cues , Recognition, Psychology , Humans , Memory , Memory Disorders , Mental Recall
12.
Mo Med ; 115(3): 230-235, 2018.
Article in English | MEDLINE | ID: mdl-30228728

ABSTRACT

Pancreatic cancer is a common gastrointestinal malignancy, and is often associated with a poor prognosis. Challenges to effective screening for pancreatic cancer include low disease prevalence and high cost of screening modalities such as endoscopic ultrasound and cross-sectional imaging. Further, most patients are asymptomatic during the early course of disease, which often leads to delay in diagnosis. Treatment options include surgery, chemotherapy, and palliative care.


Subject(s)
Adenocarcinoma/diagnosis , Pancreatic Neoplasms/diagnosis , Adenocarcinoma/pathology , Delayed Diagnosis , Humans , Pancreatic Neoplasms/pathology , Prognosis
13.
Neuroimage ; 144(Pt B): 262-269, 2017 01.
Article in English | MEDLINE | ID: mdl-26375206

ABSTRACT

This paper describes the data repository for the Cambridge Centre for Ageing and Neuroscience (Cam-CAN) initial study cohort. The Cam-CAN Stage 2 repository contains multi-modal (MRI, MEG, and cognitive-behavioural) data from a large (approximately N=700), cross-sectional adult lifespan (18-87years old) population-based sample. The study is designed to characterise age-related changes in cognition and brain structure and function, and to uncover the neurocognitive mechanisms that support healthy cognitive ageing. The database contains raw and preprocessed structural MRI, functional MRI (active tasks and resting state), and MEG data (active tasks and resting state), as well as derived scores from cognitive behavioural experiments spanning five broad domains (attention, emotion, action, language, and memory), and demographic and neuropsychological data. The dataset thus provides a depth of neurocognitive phenotyping that is currently unparalleled, enabling integrative analyses of age-related changes in brain structure, brain function, and cognition, and providing a testbed for novel analyses of multi-modal neuroimaging data.


Subject(s)
Aging/physiology , Brain , Cognition/physiology , Databases, Factual , Functional Neuroimaging/statistics & numerical data , Magnetic Resonance Imaging/statistics & numerical data , Magnetoencephalography/statistics & numerical data , Adolescent , Adult , Aged , Aged, 80 and over , Brain/anatomy & histology , Brain/diagnostic imaging , Brain/physiology , Cross-Sectional Studies , Female , Humans , Male , Middle Aged , Neurosciences/statistics & numerical data , Young Adult
15.
Conscious Cogn ; 53: 1-13, 2017 08.
Article in English | MEDLINE | ID: mdl-28558307

ABSTRACT

Processing fluency appears to influence recognition memory judgements, and the manipulation of fluency, if misattributed to an effect of prior exposure, can result in illusory memory. Although it is well established that fluency induced by masked repetition priming leads to increased familiarity, manipulations of conceptual fluency have produced conflicting results, variously affecting familiarity or recollection. Some recent studies have found that masked conceptual priming increases correct recollection (Taylor & Henson, 2012), and the magnitude of this behavioural effect correlates with analogous fMRI BOLD priming effects in brain regions associated with recollection (Taylor, Buratto, & Henson, 2013). However, the neural correlates and time-courses of masked repetition and conceptual priming were not compared directly in previous studies. The present study used event-related potentials (ERPs) to identify and compare the electrophysiological correlates of masked repetition and conceptual priming and investigate how they contribute to recognition memory. Behavioural results were consistent with previous studies: Repetition primes increased familiarity, whereas conceptual primes increased correct recollection. Masked repetition and conceptual priming also decreased the latency of late parietal component (LPC). Masked repetition priming was associated with an early P200 effect and a later parietal maximum N400 effect, whereas masked conceptual priming was only associated with a central-parietal maximum N400 effect. In addition, the topographic distributions of the N400 repetition priming and conceptual priming effects were different. These results suggest that fluency at different levels of processing is associated with different ERP components, and contributes differentially to subjective recognition memory experiences.


Subject(s)
Association , Cerebral Cortex/physiology , Evoked Potentials/physiology , Mental Recall/physiology , Recognition, Psychology/physiology , Repetition Priming/physiology , Adult , Electroencephalography , Female , Humans , Language , Male , Pattern Recognition, Visual/physiology , Young Adult
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