Digital Commons Network^™

Direct Visualization And Characterization Of The Human Zona Incerta And Surrounding Structures, Jonathan C. Lau, Yiming Xiao, Roy A.M. Haast, Greydon Gilmore, Kâmil Uludağ, Keith W. Macdougall, Ravi S. Menon, Andrew G. Parrent, Terry M. Peters, Ali R. Khan

Brain and Mind Institute Researchers' Publications

The zona incerta (ZI) is a small gray matter region of the deep brain first identified in the 19th century, yet direct in vivo visualization and characterization has remained elusive. Noninvasive detection of the ZI and surrounding region could be critical to further our understanding of this widely connected but poorly understood deep brain region and could contribute to the development and optimization of neuromodulatory therapies. We demonstrate that high resolution (submillimetric) longitudinal (T1) relaxometry measurements at high magnetic field strength (7 T) can be used to delineate the ZI from surrounding white matter structures, specifically the fasciculus cerebellothalamicus, fields …

Growth Hormone Deficiency In Megalencephaly-Capillary Malformation Syndrome: An Association With Activating Mutations In Pik3ca, Shanlee Davis, Meredith A Ware, Jordan Zeiger, Matthew A Deardorff, Katheryn Grand, Adda Grimberg, Stephanie Hsu, Megan Kelsey, Shideh Majidi, Revi P Matthew, Melanie Napier, Natalie Nokoff, Chitra Prasad, Andrew C Riggs, Margaret L Mckinnon, Ghayda Mirzaa

Paediatrics Publications

Megalencephaly-capillary malformation syndrome (MCAP) is a brain overgrowth disorder characterized by cortical malformations (specifically polymicrogyria), vascular anomalies, and segmental overgrowth secondary to somatic activating mutations in the PI3K-AKT-MTOR pathway (PIK3CA). Cases of growth failure and hypoglycemia have been reported in patients with MCAP, raising the suspicion for unappreciated growth hormone (GH) deficiency. Here we report an observational multicenter study of children with MCAP and GH deficiency. Eleven participants were confirmed to have GH deficiency, all with very low or undetectable circulating concentrations of insulin-like growth factor-1 and insulin-like growth factor binding protein-3. Seven underwent GH stimulation testing and all had …

Cortical Activation During Shoulder And Finger Movements In Healthy Adults: A Functional Near-Infrared Spectroscopy (Fnirs) Study., Chieh-Ling Yang, Shannon B Lim, Sue Peters, Janice J Eng

Physical Therapy Publications

Characterization of cortical activation patterns during movement of the upper extremity in healthy adults is helpful in understanding recovery mechanisms following neurological disorders. This study explores cortical activation patterns associated with movements of the shoulder and fingers in healthy adults using functional near-infrared spectroscopy (fNIRS). Twelve healthy right-handed participants were recruited. Two motor tasks (shoulder abduction and finger extension) with two different trial lengths (10 s and 20 s) were performed in a sitting position at a rate of 0.5 Hz. The hemodynamic response, as indicated by oxy-hemoglobin (HbO) and deoxy-hemoglobin (HbR), over both hemispheres was acquired using a 54-channel …

Direct Visualization And Characterization Of The Human Zona Incerta And Surrounding Structures, Jonathan C. Lau, Yiming Xiao, Roy A.M. Haast, Greydon Gilmore, Kâmil Uludağ, Keith W. Macdougall, Ravi S. Menon, Andrew G. Parrent, Terry M. Peters, Ali R. Khan

Medical Biophysics Publications

© 2020 The Authors. Human Brain Mapping published by Wiley Periodicals LLC. The zona incerta (ZI) is a small gray matter region of the deep brain first identified in the 19th century, yet direct in vivo visualization and characterization has remained elusive. Noninvasive detection of the ZI and surrounding region could be critical to further our understanding of this widely connected but poorly understood deep brain region and could contribute to the development and optimization of neuromodulatory therapies. We demonstrate that high resolution (submillimetric) longitudinal (T1) relaxometry measurements at high magnetic field strength (7 T) can be used to delineate …

Classifying Heterogeneous Presentations Of Ptsd Via The Default Mode, Central Executive, And Salience Networks With Machine Learning., Andrew A Nicholson, Sherain Harricharan, Maria Densmore, Richard W J Neufeld, Tomas Ros, Margaret C Mckinnon, Paul A Frewen, Jean Theberge, Rakesh Jetly, David Pedlar, Ruth A Lanius

Department of Medicine Publications

Intrinsic connectivity networks (ICNs), including the default mode network (DMN), the central executive network (CEN), and the salience network (SN) have been shown to be aberrant in patients with posttraumatic stress disorder (PTSD). The purpose of the current study was to a) compare ICN functional connectivity between PTSD, dissociative subtype PTSD (PTSD+DS) and healthy individuals; and b) to examine the use of multivariate machine learning algorithms in classifying PTSD, PTSD+DS, and healthy individuals based on ICN functional activation. Our neuroimaging dataset consisted of resting-state fMRI scans from 186 participants [PTSD (n = 81); PTSD + DS (n = 49); and …

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) …