Medicine and Health Sciences Commons^™

Identifying Canonical And Replicable Multi-Scale Intrinsic Connectivity Networks In 100k+ Resting-State Fmri Datasets., A Iraji, Z Fu, A Faghiri, M Duda, J Chen, S Rachakonda, T Deramus, P Kochunov, B M Adhikari, A Belger, J M Ford, D H Mathalon, G D Pearlson, S G Potkin, A Preda, J A Turner, T G M Van Erp, J R Bustillo, K Yang, K Ishizuka, A Faria, A Sawa, K Hutchison, E A Osuch, Jean Theberge, C Abbott, B A Mueller, D Zhi, C Zhuo, S Liu, Y Xu, M Salman, J Liu, Y Du, J Sui, T Adali, V D Calhoun

Department of Medicine Publications

Despite the known benefits of data-driven approaches, the lack of approaches for identifying functional neuroimaging patterns that capture both individual variations and inter-subject correspondence limits the clinical utility of rsfMRI and its application to single-subject analyses. Here, using rsfMRI data from over 100k individuals across private and public datasets, we identify replicable multi-spatial-scale canonical intrinsic connectivity network (ICN) templates via the use of multi-model-order independent component analysis (ICA). We also study the feasibility of estimating subject-specific ICNs via spatially constrained ICA. The results show that the subject-level ICN estimations vary as a function of the ICN itself, the data length, …

Neuroimaging-Based Classification Of Ptsd Using Data-Driven Computational Approaches: A Multisite Big Data Study From The Enigma-Pgc Ptsd Consortium., Xi Zhu, Yoojean Kim, Orren Ravid, Xiaofu He, Benjamin Suarez-Jimenez, Sigal Zilcha-Mano, Amit Lazarov, Seonjoo Lee, Chadi G Abdallah, Michael Angstadt, Christopher L Averill, C Lexi Baird, Lee A Baugh, Jennifer U Blackford, Jessica Bomyea, Steven E Bruce, Richard A Bryant, Zhihong Cao, Kyle Choi, Josh Cisler, Andrew S Cotton, Judith K Daniels, Nicholas D Davenport, Richard J Davidson, Michael D Debellis, Emily L Dennis, Maria Densmore, Terri Deroon-Cassini, Seth G Disner, Wissam El Hage, Amit Etkin, Negar Fani, Kelene A Fercho, Jacklynn Fitzgerald, Gina L Forster, Jessie L Frijling, Elbert Geuze, Atilla Gonenc, Evan M Gordon, Staci Gruber, Daniel W Grupe, Jeffrey P Guenette, Courtney C Haswell, Ryan J Herringa, Julia Herzog, David Bernd Hofmann, Bobak Hosseini, Anna R Hudson, Ashley A Huggins, Jonathan C Ipser, Neda Jahanshad, Meilin Jia-Richards, Tanja Jovanovic, Milissa L Kaufman, Mitzy Kennis, Anthony King, Philipp Kinzel, Saskia B J Koch, Inga K Koerte, Sheri M Koopowitz, Mayuresh S Korgaonkar, John H Krystal, Ruth Lanius, Christine L Larson, Lauren A M Lebois, Gen Li, Israel Liberzon, Guang Ming Lu, Yifeng Luo, Vincent A Magnotta, Antje Manthey, Adi Maron-Katz, Geoffery May, Katie Mclaughlin, Sven C Mueller, Laura Nawijn, Steven M Nelson, Richard W J Neufeld, Jack B Nitschke, Erin M O'Leary, Bunmi O Olatunji, Miranda Olff, Matthew Peverill, K Luan Phan, Rongfeng Qi, Yann Quidé, Ivan Rektor, Kerry Ressler, Pavel Riha, Marisa Ross, Isabelle M Rosso, Lauren E Salminen, Kelly Sambrook, Christian Schmahl, Martha E Shenton, Margaret Sheridan, Chiahao Shih, Maurizio Sicorello, Anika Sierk, Alan N Simmons, Raluca M Simons, Jeffrey S Simons, Scott R Sponheim, Murray B Stein, Dan J Stein, Jennifer S Stevens, Thomas Straube, Delin Sun, Jean Theberge, Paul M Thompson, Sophia I Thomopoulos, Nic J A Van Der Wee, Steven J A Van Der Werff, Theo G M Van Erp, Sanne J H Van Rooij, Mirjam Van Zuiden, Tim Varkevisser, Dick J Veltman, Robert R J M Vermeiren, Henrik Walter, Li Wang, Xin Wang, Carissa Weis, Sherry Winternitz, Hong Xie, Ye Zhu, Melanie Wall, Yuval Neria, Rajendra A Morey

Department of Medicine Publications

BACKGROUND: Recent advances in data-driven computational approaches have been helpful in devising tools to objectively diagnose psychiatric disorders. However, current machine learning studies limited to small homogeneous samples, different methodologies, and different imaging collection protocols, limit the ability to directly compare and generalize their results. Here we aimed to classify individuals with PTSD versus controls and assess the generalizability using a large heterogeneous brain datasets from the ENIGMA-PGC PTSD Working group.

METHODS: We analyzed brain MRI data from 3,477 structural-MRI; 2,495 resting state-fMRI; and 1,952 diffusion-MRI. First, we identified the brain features that best distinguish individuals with PTSD from controls …

Increased Top-Down Control Of Emotions During Symptom Provocation Working Memory Tasks Following A Rct Of Alpha-Down Neurofeedback In Ptsd., Saurabh Bhaskar Shaw, Andrew A Nicholson, Tomas Ros, Sherain Harricharan, Braeden Terpou, Maria Densmore, Jean Theberge, Paul Frewen, Ruth A Lanius

Department of Medicine Publications

BACKGROUND: Posttraumatic stress disorder (PTSD) has been found to be associated with emotion under-modulation from the prefrontal cortex and a breakdown of the top-down control of cognition and emotion. Novel adjunct therapies such as neurofeedback (NFB) have been shown to normalize aberrant neural circuits that underlie PTSD psychopathology at rest. However, little evidence exists for NFB-linked neural improvements under emotionally relevant cognitive load. The current study sought to address this gap by examining the effects of alpha-down NFB in the context of an emotional n-back task.

METHODS: We conducted a 20-week double-blind randomized, sham-controlled trial of alpha-down NFB and collected …

How The Body Remembers: Examining The Default Mode And Sensorimotor Networks During Moral Injury Autobiographical Memory Retrieval In Ptsd., Breanne E Kearney, Braeden A Terpou, Maria Densmore, Saurabh B Shaw, Jean Theberge, Rakesh Jetly, Margaret C Mckinnon, Ruth A Lanius

Department of Medicine Publications

Neural representations of sensory percepts and motor responses constitute key elements of autobiographical memory. However, these representations may remain as unintegrated sensory and motor fragments in traumatic memory, thus contributing toward re-experiencing and reliving symptoms in trauma-related conditions such as post-traumatic stress disorder (PTSD). Here, we investigated the sensorimotor network (SMN) and posterior default mode network (pDMN) using a group independent component analysis (ICA) by examining their functional connectivity during a script-driven memory retrieval paradigm of (potentially) morally injurious events in individuals with PTSD and healthy controls. Moral injury (MI), where an individual acts or fails to act in a …

Planning System For The Optimization Of Electric Field Delivery Using Implanted Electrodes For Brain Tumor Control, Erin Iredale, Brynn Voigt, Adam Rankin, Kyungho W Kim, Jeff Z Chen, Susanne Schmid, Matthew O Hebb, Terry M Peters, Eugene Wong

Anatomy and Cell Biology Publications

BACKGROUND: The use of non-ionizing electric fields from low-intensity voltage sources (< 10 V) to control malignant tumor growth is showing increasing potential as a cancer treatment modality. A method of applying these low-intensity electric fields using multiple implanted electrodes within or adjacent to tumor volumes has been termed as intratumoral modulation therapy (IMT).

PURPOSE: This study explores advancements in the previously established IMT optimization algorithm, and the development of a custom treatment planning system for patient-specific IMT. The practicality of the treatment planning system is demonstrated by implementing the full optimization pipeline on a brain phantom with robotic electrode implantation, postoperative imaging, and treatment stimulation.

METHODS: The integrated planning pipeline in 3D Slicer begins with importing and segmenting patient magnetic resonance images (MRI) or computed tomography (CT) images. The segmentation process is manual, followed by a semi-automatic smoothing step that allows …

In Vivo Magnetic Resonance Spectroscopy Of Hyperpolarized [1-, Lauren M Smith, Conrad B Pitts, Lanette J Friesen-Waldner, Neetin H Prabhu, Katherine E Mathers, Kevin J Sinclair, Trevor P Wade, Timothy Regnault, Charles A Mckenzie

Paediatrics Publications

BACKGROUND: Alterations in glycolysis are central to the increasing incidence of non-alcoholic fatty liver disease (NAFLD), highlighting a need for in vivo, non-invasive technologies to understand the development of hepatic metabolic aberrations.

PURPOSE: To use hyperpolarized magnetic resonance spectroscopy (MRS) and proton density fat fraction (PDFF) magnetic resonance imaging (MRI) techniques to investigate the effects of a chronic, life-long exposure to the Western diet (WD) in an animal model resulting in NAFLD; to investigate the hypothesis that exposure to the WD will result in NAFLD in association with altered pyruvate metabolism.

STUDY TYPE: Prospective.

ANIMAL MODEL: Twenty-eight male guinea pigs …

Water-Fat Magnetic Resonance Imaging Of Adipose Tissue Compartments In The Normal Third Trimester Fetus, Stephanie A Giza, Tianna L Koreman, Simran Sethi, Michael R Miller, Debbie A Penava, Genevieve D Eastabrook, Charles A Mckenzie, Barbra De Vrijer

Obstetrics & Gynaecology Publications

BACKGROUND: Assessment of fetal adipose tissue gives information about the future metabolic health of an individual, with evidence that the development of this tissue has regional heterogeneity.

OBJECTIVE: To assess differences in the proton density fat fraction (PDFF) between fetal adipose tissue compartments in the third trimester using water-fat magnetic resonance imaging (MRI).

MATERIALS AND METHODS: Water-fat MRI was performed in a 1.5-T scanner. Fetal adipose tissue was segmented into cheeks, thorax, abdomen, upper arms, forearms, thighs and lower legs. PDFF and R2* values were measured in each compartment.

RESULTS: Twenty-eight women with singleton pregnancies were imaged between 28 and …

Atrx Deletion In Neurons Leads To Sexually Dimorphic Dysregulation Of Mir-137 And Spatial Learning And Memory Deficits., Renee J. Tamming, Vanessa Dumeaux, Yan Jiang, Sarfraz Shafiq, Luana Langlois, Jacob Ellegood, Lily R. Qiu, Jason P. Lerch, Nathalie G. Bérubé

Paediatrics Publications

ATRX gene mutations have been identified in syndromic and non-syndromic intellectual disabilities in humans. ATRX is known to maintain genomic stability in neuroprogenitor cells, but its function in differentiated neurons and memory processes remains largely unresolved. Here, we show that the deletion of neuronal Atrx in mice leads to distinct hippocampal structural defects, fewer presynaptic vesicles, and an enlarged postsynaptic area at CA1 apical dendrite-axon junctions. We identify male-specific impairments in long-term contextual memory and in synaptic gene expression, linked to altered miR-137 levels. We show that ATRX directly binds to the miR-137 locus and that the enrichment of the …

Osteochondritis Dissecans In Pediatric Patients With Juvenile Idiopathic Arthritis., Bradley C Jackson, Debra L Bartley, Roberta A Berard

Paediatrics Publications

No abstract provided.

The Hijacked Self: Disrupted Functional Connectivity Between The Periaqueductal Gray And The Default Mode Network In Posttraumatic Stress Disorder Using Dynamic Causal Modeling., Braeden A Terpou, Maria Densmore, Jean Theberge, Paul Frewen, Margaret C Mckinnon, Andrew A Nicholson, Ruth A Lanius

Department of Medicine Publications

Self-related processes define assorted self-relevant or social-cognitive functions that allow us to gather insight and to draw inferences related to our own mental conditions. Self-related processes are mediated by the default mode network (DMN), which, critically, shows altered functionality in individuals with posttraumatic stress disorder (PTSD). In PTSD, the midbrain periaqueductal gray (PAG) demonstrates stronger functional connectivity with the DMN [i.e., precuneus (PCN), medial prefrontal cortex (mPFC)] as compared to healthy individuals during subliminal, trauma-related stimulus processing. Here, we analyzed the directed functional connectivity between the PAG and the PCN, as well as between the PAG and the mPFC to …

A Randomized, Controlled Trial Of Alpha-Rhythm Eeg Neurofeedback In Posttraumatic Stress Disorder: A Preliminary Investigation Showing Evidence Of Decreased Ptsd Symptoms And Restored Default Mode And Salience Network Connectivity Using Fmri., Andrew A Nicholson, Tomas Ros, Maria Densmore, Paul A Frewen, Richard W J Neufeld, Jean Theberge, Rakesh Jetly, Ruth A Lanius

Department of Medicine Publications

OBJECTIVE: The default-mode network (DMN) and salience network (SN) have been shown to display altered connectivity in posttraumatic stress disorder (PTSD). Restoring aberrant connectivity within these networks with electroencephalogram neurofeedback (EEG-NFB) has been shown previously to be associated with acute decreases in symptoms. Here, we conducted a double-blind, sham-controlled randomized trial of alpha-rhythm EEG-NFB in participants with PTSD (n = 36) over 20-weeks. Our aim was to provide mechanistic evidence underlying clinical improvements by examining changes in network connectivity via fMRI.

METHODS: We randomly assigned participants with a primary diagnosis of PTSD to either the experimental group (n = 18) …

Chronic Obstructive Pulmonary Disease: Thoracic Ct Texture Analysis And Machine Learning To Predict Pulmonary Ventilation, Andrew Westcott, Dante P I Capaldi, David G Mccormack, Aaron D Ward, Aaron Fenster, Grace Parraga

Medical Biophysics Publications

Background Fixed airflow limitation and ventilation heterogeneity are common in chronic obstructive pulmonary disease (COPD). Conventional noncontrast CT provides airway and parenchymal measurements but cannot be used to directly determine lung function. Purpose To develop, train, and test a CT texture analysis and machine-learning algorithm to predict lung ventilation heterogeneity in participants with COPD. Materials and Methods In this prospective study (

An Accurate Registration Of The Bigbrain Dataset With The Mni Pd25 And Icbm152 Atlases., Yiming Xiao, Jonathan C Lau, Taylor Anderson, Jordan Dekraker, D Louis Collins, Terry Peters, Ali R Khan

Brain and Mind Institute Researchers' Publications

Brain atlases that encompass detailed anatomical or physiological features are instrumental in the research and surgical planning of various neurological conditions. Magnetic resonance imaging (MRI) has played important roles in neuro-image analysis while histological data remain crucial as a gold standard to guide and validate such analyses. With cellular-scale resolution, the BigBrain atlas offers 3D histology of a complete human brain, and is highly valuable to the research and clinical community. To bridge the insights at macro- and micro-levels, accurate mapping of BigBrain and established MRI brain atlases is necessary, but the existing registration is unsatisfactory. The described dataset includes …

A Framework For Evaluating Correspondence Between Brain Images Using Anatomical Fiducials., Jonathan C Lau, Andrew G Parrent, John Demarco, Geetika Gupta, Jason Kai, Olivia W Stanley, Tristan Kuehn, Patrick J Park, Kayla Ferko, Ali R Khan, Terry M Peters

Brain and Mind Institute Researchers' Publications

Accurate spatial correspondence between template and subject images is a crucial step in neuroimaging studies and clinical applications like stereotactic neurosurgery. In the absence of a robust quantitative approach, we sought to propose and validate a set of point landmarks, anatomical fiducials (AFIDs), that could be quickly, accurately, and reliably placed on magnetic resonance images of the human brain. Using several publicly available brain templates and individual participant datasets, novice users could be trained to place a set of 32 AFIDs with millimetric accuracy. Furthermore, the utility of the AFIDs protocol is demonstrated for evaluating subject-to-template and template-to-template registration. Specifically, …

Hyperpolarized Helium 3 Mri In Mild-To-Moderate Asthma: Prediction Of Postbronchodilator Reversibility, Rachel L Eddy, Sarah Svenningsen, Christopher Licskai, David G Mccormack, Grace Parraga

Medical Biophysics Publications

Background: Longitudinal progression to irreversible airflow limitation occurs in approximately 10% of patients with asthma, but it is difficult to identify patients who are at risk for this transition.

Purpose: To investigate 6-year longitudinal changes in hyperpolarized helium 3 (3He) MRI ventilation defects in study participants with mild-to-moderate asthma and identify predictors of longitudinal changes in postbronchodilator forced expiratory volume in 1 second (FEV1) reversibility

Materials and Methods: Spirometry and hyperpolarized 3He MRI were evaluated in participants with mild-to-moderate asthma in two prospectively planned visits approximately 6 years apart. Participants underwent methacholine challenge at baseline (January 2010 to April 2011) …

Brain Activity Associated With Dual-Task Performance Of Ankle Motor Control During Cognitive Challenge., Sue Peters, Janice J Eng, Teresa Liu-Ambrose, Michael R Borich, Elizabeth Dao, Ameen Amanian, Lara A Boyd

Physical Therapy Publications

INTRODUCTION: Skilled Ankle motor control is frequently required while performing secondary cognitively demanding tasks such as socializing and avoiding obstacles while walking, termed "Dual tasking." It is likely that Dual-task performance increases demand on the brain, as both motor and cognitive systems require neural resources. The purpose of this study was to use functional MRI to understand which brain regions are involved in resolving Dual-task interference created by requiring high levels of Ankle motor control during a cognitive task.

METHODS: Using functional MRI, brain activity was measured in sixteen young adults during performance of visually cued Ankle plantar flexion to …

Oscillometry And Pulmonary Magnetic Resonance Imaging In Asthma And Copd, Rachel L Eddy, Andrew Westcott, Geoffrey N Maksym, Grace Parraga, Ronald J Dandurand

Medical Biophysics Publications

Developed over six decades ago, pulmonary oscillometry has re-emerged as a noninvasive and effort-independent method for evaluating respiratory-system impedance in patients with obstructive lung disease. Here, we evaluated the relationships between hyperpolarized

Linked Mri Signatures Of The Brain's Acute And Persistent Response To Concussion In Female Varsity Rugby Players., Kathryn Y Manning, Alberto Llera, Gregory A Dekaban, Robert Bartha, Christy Barreira, Arthur Brown, Lisa Fischer, Tatiana Jevremovic, Kevin Blackney, Timothy J Doherty, Douglas D Fraser, Jeff Holmes, Christian F Beckmann, Ravi S Menon

Paediatrics Publications

Acute brain changes are expected after concussion, yet there is growing evidence of persistent abnormalities well beyond clinical recovery and clearance to return to play. Multiparametric MRI is a powerful approach to non-invasively study structure-function relationships in the brain, however it remains challenging to interpret the complex and heterogeneous cascade of brain changes that manifest after concussion. Emerging conjunctive, data-driven analysis approaches like linked independent component analysis can integrate structural and functional imaging data to produce linked components that describe the shared inter-subject variance across images. These linked components not only offer the potential of a more comprehensive understanding of …

White Matter Biomarkers Associated With Motor Change In Individuals With Stroke: A Continuous Theta Burst Stimulation Study, K P Wadden, Sue Peters, M R Borich, J L Neva, K S Hayward, C S Mang, N J Snow, K E Brown, T S Woodward, S K Meehan, L A Boyd

Physical Therapy Publications

Continuous theta burst stimulation (cTBS) is a form of noninvasive repetitive brain stimulation that, when delivered over the contralesional hemisphere, can influence the excitability of the ipsilesional hemisphere in individuals with stroke. cTBS applied prior to skilled motor practice interventions may augment motor learning; however, there is a high degree of variability in individual response to this intervention. The main objective of the present study was to assess white matter biomarkers of response to cTBS paired with skilled motor practice in individuals with chronic stroke. We tested the effects of stimulation of the contralesional hemisphere at the site of the …

Complexity In Mood Disorder Diagnosis: Fmri Connectivity Networks Predicted Medication-Class Of Response In Complex Patients, E Osuch, S Gao, M Wammes, Jean Theberge, P Willimason, R J Neufeld, Y Du, J Sui, V Calhoun

Department of Medicine Publications

OBJECTIVE: This study determined the clinical utility of an fMRI classification algorithm predicting medication-class of response in patients with challenging mood diagnoses.

METHODS: Ninety-nine 16-27-year-olds underwent resting state fMRI scans in three groups-BD, MDD and healthy controls. A predictive algorithm was trained and cross-validated on the known-diagnosis patients using maximally spatially independent components (ICs), constructing a similarity matrix among subjects, partitioning the matrix in kernel space and optimizing support vector machine classifiers and IC combinations. This classifier was also applied to each of 12 new individual patients with unclear mood disorder diagnoses.

RESULTS: Classification within the known-diagnosis group was approximately …

Magnetic Resonance Imaging In The Diagnosis Of White Matter Signal Abnormalities., Ravi Datar, Asuri Narayan Prasad, Keng Yeow Tay, Charles Anthony Rupar, Pavlo Ohorodnyk, Michael Miller, Chitra Prasad

Paediatrics Publications

Background White matter abnormalities (WMAs) pose a diagnostic challenge when trying to establish etiologic diagnoses. During childhood and adult years, genetic disorders, metabolic disorders and acquired conditions are included in differential diagnoses. To assist clinicians and radiologists, a structured algorithm using cranial magnetic resonance imaging (MRI) has been recommended to aid in establishing working diagnoses that facilitate appropriate biochemical and genetic investigations. This retrospective pilot study investigated the validity and diagnostic utility of this algorithm when applied to white matter signal abnormalities (WMSAs) reported on imaging studies of patients seen in our clinics. Methods The MRI algorithm was applied to …

Oscillometry And Pulmonary Mri Measurements Of Ventilation Heterogeneity In Obstructive Lung Disease: Relationship To Quality Of Life And Disease Control, Heather M Young, Fumin Guo, Rachel L Eddy, Geoffrey Maksym, Grace Parraga

Medical Biophysics Publications

Ventilation heterogeneity is a hallmark finding in obstructive lung disease and may be evaluated using a variety of methods, including multiple-breath gas washout and pulmonary imaging. Such methods provide an opportunity to better understand the relationships between structural and functional abnormalities in the lungs, and their relationships with important clinical outcomes. We measured ventilation heterogeneity and respiratory impedance in 100 subjects [50 patients with asthma, 22 ex-smokers, and 28 patients with chronic obstructive pulmonary disease (COPD)] using oscillometry and hyperpolarized

Type-2 Diabetes Mellitus Reduces Cortical Thickness And Decreases Oxidative Metabolism In Sensorimotor Regions After Stroke., Jennifer K Ferris, Sue Peters, Katlyn E Brown, Katherine Tourigny, Lara A Boyd

Physical Therapy Publications

Individuals with type-2 diabetes mellitus experience poor motor outcomes after ischemic stroke. Recent research suggests that type-2 diabetes adversely impacts neuronal integrity and function, yet little work has considered how these neuronal changes affect sensorimotor outcomes after stroke. Here, we considered how type-2 diabetes impacted the structural and metabolic function of the sensorimotor cortex after stroke using volumetric magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS). We hypothesized that the combination of chronic stroke and type-2 diabetes would negatively impact the integrity of sensorimotor cortex as compared to individuals with chronic stroke alone. Compared to stroke alone, individuals with …

Free-Breathing Pulmonary Mr Imaging To Quantify Regional Ventilation, Dante P I Capaldi, Rachel L Eddy, Sarah Svenningsen, Fumin Guo, John S H Baxter, A Jonathan Mcleod, Parameswaran Nair, David G Mccormack, Grace Parraga

Medical Biophysics Publications

Purpose: To measure regional specific ventilation with free-breathing hydrogen 1 (1H) magnetic resonance (MR) imaging without exogenous contrast material and to investigate correlations with hyperpolarized helium 3 (3He) MR imaging and pulmonary function test measurements in healthy volunteers and patients with asthma.

Materials and Methods: Subjects underwent free-breathing 1H and static breath-hold hyperpolarized 3He MR imaging as well as spirometry and plethysmography; participants were consecutively recruited between January and June 2017. Free-breathing 1H MR imaging was performed with an optimized balanced steady-state free-precession sequence; images were retrospectively grouped into tidal inspiration or tidal expiration volumes with exponentially weighted phase interpolation. …

Human Neuroimaging Reveals The Subcomponents Of Grasping, Reaching And Pointing Actions., Cristiana Cavina-Pratesi, Jason D Connolly, Simona Monaco, Teresa D Figley, A David Milner, Thomas Schenk, Jody C Culham

Brain and Mind Institute Researchers' Publications

Although the neural underpinnings of visually guided grasping and reaching have been well delineated within lateral and medial fronto-parietal networks (respectively), the contributions of subcomponents of visuomotor actions have not been explored in detail. Using careful subtraction logic, here we investigated which aspects of grasping, reaching, and pointing movements drive activation across key areas within visuomotor networks implicated in hand actions. For grasping tasks, we find activation differences based on the precision required (fine > coarse grip: anterior intraparietal sulcus, aIPS), the requirement to lift the object (grip + lift > grip: aIPS; dorsal premotor cortex, PMd; and supplementary motor area, SMA), …

Disruption To Functional Networks In Neonates With Perinatal Brain Injury Predicts Motor Skills At 8 Months, Annika C Linke, Conor Wild, Leire Zubiaurre-Elorza, Charlotte Herzmann, Hester Duffy, Victor K Han, David S C Lee, Rhodri Cusack

Paediatrics Publications

Objective

Functional connectivity magnetic resonance imaging (fcMRI) of neonates with perinatal brain injury could improve prediction of motor impairment before symptoms manifest, and establish how early brain organization relates to subsequent development. This cohort study is the first to describe and quantitatively assess functional brain networks and their relation to later motor skills in neonates with a diverse range of perinatal brain injuries.

Methods

Infants (n = 65, included in final analyses: n = 53) were recruited from the neonatal intensive care unit (NICU) and were stratified based on their age at birth (prematurevs. term), and on whether neuropathology …

Mri Ventilation Abnormalities Predict Quality-Of-Life And Lung Function Changes In Mild-To-Moderate Copd: Longitudinal Tincan Study, Miranda Kirby, Rachel L Eddy, Damien Pike, Sarah Svenningsen, Harvey O Coxson, Don D Sin, David G Mccormack, Grace Parraga

Medical Biophysics Publications

CT biomarkers of emphysema (15th percentile of the CT density histogram, HU15%) and airways disease (wall thickness of airways with 10 mm internal perimeter, Pi10) have shown promise for providing prognostic information.2 Although recent data3 showed that the change in CT emphysema may be used to estimate the efficacy of therapy in patients with α-1-antitrypsin-deficiency, thus far none of the currently developed CT biomarkers have been shown to reflect changes in outcomes that are important to patients with COPD. MRI with inhaled noble gases provide highly sensitive and unique microstructural and functional information in COPD.4 MRI biomarkers of COPD are …

Quantitative Assessment Of White Matter Injury In Preterm Neonates: Association With Outcomes., Ting Guo, Emma G Duerden, Elysia Adams, Vann Chau, Helen M Branson, M Mallar Chakravarty, Kenneth J Poskitt, Anne Synnes, Ruth E Grunau, Steven P Miller

Brain and Mind Institute Researchers' Publications

OBJECTIVE: To quantitatively assess white matter injury (WMI) volume and location in very preterm neonates, and to examine the association of lesion volume and location with 18-month neurodevelopmental outcomes.

METHODS: Volume and location of WMI was quantified on MRI in 216 neonates (median gestational age 27.9 weeks) who had motor, cognitive, and language assessments at 18 months corrected age (CA). Neonates were scanned at 32.1 postmenstrual weeks (median) and 68 (31.5%) had WMI; of 66 survivors, 58 (87.9%) had MRI and 18-month outcomes. WMI was manually segmented and transformed into a common image space, accounting for intersubject anatomical variability. Probability …

Brainstem Shape Is Affected By Clinical Course In The Neonatal Intensive Care Unit, Marcus Lo, Leire Zubiaurre-Elorza, Conor Wild, Annika C Linke, David S C Lee, Victor K Han, Rhodri Cusack

Paediatrics Publications

The brainstem, critical for motor function, autonomic regulation, and many neurocognitive functions, undergoes rapid development from the third trimester. Accordingly, we hypothesized it would be vulnerable to insult during this period, and that a difficult clinical course in the neonatal intensive care unit (NICU) would affect development, and be reflected through atypical shape. Our study population consisted of 66 neonates - all inpatients from the NICU at Victoria Hospital, London Health Sciences Centre, ON, Canada, of which 45 entered the final analysis. The cohort varied in gestational age (GA) and ranged from neurologically healthy to severely brain-injured. Structural MRI was …

Desynchronization Of Autonomic Response And Central Autonomic Network Connectivity In Posttraumatic Stress Disorder, Janine Thome, Maria Densmore, Paul A Frewen, Margaret C Mckinnon, Jean Théberge, Andrew A Nicholson, Julian Koenig, Julian F Thayer, Ruth A Lanius

Department of Medicine Publications

OBJECTIVES: Although dysfunctional emotion regulatory capacities are increasingly recognized as contributing to posttraumatic stress disorder (PTSD), little work has sought to identify biological markers of this vulnerability. Heart rate variability (HRV) is a promising biomarker that, together with neuroimaging, may assist in gaining a deeper understanding of emotion dysregulation in PTSD. The objective of the present study was, therefore, to characterize autonomic response patterns, and their related neuronal patterns in individuals with PTSD at rest.

METHODS: PTSD patients (N = 57) and healthy controls (N = 41) underwent resting-state fMRI. Connectivity patterns of key regions within the central autonomic network …