Medicine and Health Sciences Commons^™

Share Cannabidiol Exposure During Gestation Leads To Adverse Cardiac Outcomes Early In Postnatal Life In Male Rat Offspring., Daniel B. Hardy, Steven R. Laviolette, Kendrick Lee, David Rc Natale

Physiology and Pharmacology Publications

Introduction: Studies indicate that *7% of pregnant individuals in North America consume cannabis in pregnancy. Pre-clinical studies have established that maternal exposure to D9-tetrahydrocannabinol (THC; major psychoactive component in cannabis) leads to fetal growth restriction and impaired cardiac function in offspring. However, the effects of maternal exposure to cannabidiol (CBD; major non-euphoric constituent) on cardiac outcomes in offspring remain unknown. Therefore, our objective is to investigate the functional and underlying molecular impacts in the hearts of offspring exposed to CBD in pregnancy. Methods: Pregnant Wistar rats were exposed to either 3 or 30mg/kg CBD or vehicle control i.p. daily from …

Cannabidiol Exposure During Rat Pregnancy Leads To Labyrinth-Specific Vascular Defects In The Placenta And Reduced Fetal Growth, Daniel B. Hardy, David R C Natale, Kendrick Lee

Physiology and Pharmacology Publications

Introduction: Cannabis use is increasing among pregnant people, and cannabidiol (CBD), a constituent of cannabis, is often perceived as ‘‘natural’’ and ‘‘safe’’ as it is non-intoxicating. In utero, cannabis exposure is associated with negative health outcomes, including fetal growth restriction (FGR). The placenta supplies oxygen and nutrients to the fetus, and alterations in placental development can lead to FGR. While there has been some investigation into the effects of D9-THC, there has been limited investigation into the impacts of in utero gestational CBD exposure on the placenta. Methods: This study used histological and transcriptomic analysis of embryonic day (E)19.5 rat …

Are Sub-Saharan African National Food And Agriculture Policies Nutrition-Sensitive? A Case Study Of Ethiopia, Ghana, Malawi, Nigeria, And South Africa, Roshaany Asirvatham

Health Studies Publications

Background

In sub-Saharan Africa (SSA), malnutrition coupled with rising rates of undernutrition and the burden of overweight/obesity remains one of the most significant public health challenges facing the region. Nutrition-sensitive agriculture can play an important role in reducing malnutrition by addressing the underlying causes of nutrition outcomes. Therefore, we aim to assess the nutrition-sensitivity of food and agriculture policies in SSA and to provide recommendations for identified policy challenges in implementing nutrition-sensitive agriculture initiatives.

Methods

We assessed past and current national policies relevant to agriculture and nutrition from Ethiopia, Ghana, Malawi, Nigeria, and South Africa. Thirty policies and strategies were …

Estimation Of Free Water-Corrected Microscopic Fractional Anisotropy., Nico J J Arezza, Tales Santini, Mohammad Omer, Corey A Baron

Medical Biophysics Publications

Water diffusion anisotropy MRI is sensitive to microstructural changes in the brain that are hallmarks of various neurological conditions. However, conventional metrics like fractional anisotropy are confounded by neuron fiber orientation dispersion, and the relatively low resolution of diffusion-weighted MRI gives rise to significant free water partial volume effects in many brain regions that are adjacent to cerebrospinal fluid. Microscopic fractional anisotropy is a recent metric that can report water diffusion anisotropy independent of neuron fiber orientation dispersion but is still susceptible to free water contamination. In this paper, we present a free water elimination (FWE) technique to estimate microscopic …

Dentate Gyrus Integrity Is Necessary For Behavioral Pattern Separation But Not Statistical Learning, Helena Shizhe Wang, R. Shayna Rosenbaum, Stevenson Baker, Claire Lauzon, Laura Batterink, Stefan Köhler

Brain and Mind Institute Researchers' Publications

Pattern separation, the creation of distinct representations of similar inputs, and statistical learning, the rapid extraction of regularities across multiple inputs, have both been linked to hippocampal processing. It has been proposed that there may be functional differentiation within the hippocampus, such that the trisynaptic pathway (entorhinal cortex > dentate gyrus > CA3 > CA1) supports pattern separation, whereas the monosynaptic pathway (entorhinal cortex > CA1) supports statistical learning. To test this hypothesis, we investigated the behavioral expression of these two processes in BL, an individual with highly selective bilateral lesions in the dentate gyrus that presumably disrupts the trisynaptic pathway. We tested pattern …

Long Term Outcomes After Norse: Treatment With Vagus Nerve Stimulation, Poul H. Espino, Jorge G. Burneo, Gaby Moscol, Teneille Gofton, Keith Macdougall, Ana Suller-Marti

Brain and Mind Institute Researchers' Publications

New-onset refractory status epilepticus (NORSE) is associated with high mortality, therapy resistant epilepsy (TRE) and poor cognitive and functional outcomes. Some patients develop multifocal TRE, for whom surgery with a curative intention, is not an option. In these patients, Vagus Nerve Stimulation (VNS) is performed as a palliative treatment. We report the long-term outcomes regarding seizure frequency, functional and cognitive outcome, and effectiveness of VNS in two patients with TRE as a consequence of NORSE. In the first patient with cryptogenic NORSE, VNS implantation occurred during the acute stage, probably contributing to the cessation of her status epilepticus. However, in …

No Statistical Learning Advantage In Children Over Adults: Evidence From Behaviour And Neural Entrainment., Christine N Moreau, Marc F. Joanisse, Jerrica Mulgrew, Laura J. Batterink

Brain and Mind Institute Researchers' Publications

Explicit recognition measures of statistical learning (SL) suggest that children and adults have similar linguistic SL abilities. However, explicit tasks recruit additional cognitive processes that are not directly relevant for SL and may thus underestimate children's true SL capacities. In contrast, implicit tasks and neural measures of SL should be less influenced by explicit, higher-level cognitive abilities and thus may be better suited to capturing developmental differences in SL. Here, we assessed SL to six minutes of an artificial language in English-speaking children (n = 56, 24 females, M = 9.98 years) and adults (n = 44; 31 females, M …

An Open Access Resource For Functional Brain Connectivity From Fully Awake Marmosets, David J. Schaeffer, L Martyn Klassen, Yuki Hori, Xiaoguang Tian, Diego Szczupak, Cecil Chern-Chyi Yen, Justine C. Cléry, Kyle M. Gilbert, Joseph S. Gati, Ravi S. Menon, Cirong Liu, Stefan Everling, Afonso C. Silva

Brain and Mind Institute Researchers' Publications

The common marmoset (Callithrix jacchus) is quickly gaining traction as a premier neuroscientific model. However, considerable progress is still needed in understanding the functional and structural organization of the marmoset brain to rival that documented in longstanding preclinical model species, like mice, rats, and Old World primates. To accelerate such progress, we present the Marmoset Functional Brain Connectivity Resource (marmosetbrainconnectome.org), currently consisting of over 70 h of resting-state fMRI (RS-fMRI) data acquired at 500 µm isotropic resolution from 31 fully awake marmosets in a common stereotactic space. Three-dimensional functional connectivity (FC) maps for every cortical and subcortical gray matter voxel …

Ex Vivo Thrombus Magnetic Resonance Imaging Features And Patient Clinical Data Enable Prediction Of Acute Ischemic Stroke Cause, Spencer D. Christiansen, Junmin Liu, Maria Bres Bullrich, Manas Sharma, Sachin K. Pandey, Melfort Boulton, Sebastian Fridman, Luciano A. Sposato, Maria Drangova

Robarts Vascular Research Publications

The cause of ischemic stroke often remains elusive even after full stroke workup is completed. Cardioembolic mechanisms in particular are frequently presumed but challenging to definitively diagnose. Quantitative thrombus texture analysis is emerging as a powerful tool for stroke characterization, having shown the ability to predict response to stroke treatment,1 but its ability to predict stroke cause and complement machine learning models built from standard clinical features has not been studied.2, 3 The purpose of this study is to evaluate the ability of radiomics features extracted from quantitative magnetic resonance images of retrieved ischemic stroke thrombi (R2*(=1/T2*), …

A Neural Signature Of Regularity In Sound Is Reduced In Older Adults, Björn Herrmann, Burkhard Maess, Ingrid S. Johnsrude

Brain and Mind Institute Researchers' Publications

Sensitivity to repetitions in sound amplitude and frequency is crucial for sound perception. As with other aspects of sound processing, sensitivity to such patterns may change with age, and may help explain some age-related changes in hearing such as segregating speech from background sound. We recorded magnetoencephalography to characterize differences in the processing of sound patterns between younger and older adults. We presented tone sequences that either contained a pattern (made of a repeated set of tones) or did not contain a pattern. We show that auditory cortex in older, compared to younger, adults is hyperresponsive to sound onsets, but …

Completing The Puzzle: Why Studies In Non-Human Primates Are Needed To Better Understand The Effects Of Non-Invasive Brain Stimulation, Sebastian J. Lehmann, Brian D. Corneil

Brain and Mind Institute Researchers' Publications

Brain stimulation is a core method in neuroscience. Numerous non-invasive brain stimulation (NIBS) techniques are currently in use in basic and clinical research, and recent advances promise the ability to non-invasively access deep brain structures. While encouraging, there is a surprising gap in our understanding of precisely how NIBS perturbs neural activity throughout an interconnected network, and how such perturbed neural activity ultimately links to behaviour. In this review, we will consider why non-human primate (NHP) models of NIBS are ideally situated to address this gap in knowledge, and why the oculomotor network that moves our line of sight offers …

Developing A Nasal Organotypic Model To Investigate The Effects Of The Nasal Microbiome On The Susceptibility To Pathogens, Victor Lam

2022 Undergraduate Awards

The nasal mucosa is colonized by diverse bacteria, however, the influence of the nasal microbiome on the susceptibility of respiratory pathogens in adults is poorly understood. Defining the complex relationship requires a relevant in vitro model, but current nasal models fail to differentiate into a pseudostratified columnar epithelium that mimicsthe nasal milieu. Hence, these models can not support the investigation of these aspects concurrently. In this study, we established an in vitro human primary nasal epithelial model using the air-liquid interface (ALI) condition. Commercially available and locally isolated nasal cells were successfully differentiated into pseudostratified columnar epithelia. The differentiated epithelium …

Learning Words Without Trying: Daily Second Language Podcasts Support Word Form Learning In Adults, Elise Alexander, Stephen C. Van Hedger, Laura Batterink

Brain and Mind Institute Researchers' Publications

Spoken language contains overlapping patterns across different levels, from syllables to words to phrases. The discovery of these structures may be partially supported by statistical learning (SL), the unguided, automatic extraction of regularities from the environment through passive exposure. SL supports word learning in artificial language experiments, but few studies have examined whether it scales up to support natural language learning in adult second language learners. Here, adult English speakers (n = 70) listened to daily podcasts in either Italian or English for two weeks while going about their normal routines. To measure word knowledge, participants provided familiarity ratings of …

Putative Concussion Biomarkers Identified In Adolescent Male Athletes Using Targeted Plasma Proteomics, Michael R. Miller, Michael Robinson, Lisa Fischer, Alicia Dibattista, Maitray A. Patel, Mark Daley, Robert Bartha, Gregory A. Dekaban, Ravi S. Menon, J. Kevin Shoemaker, Eleftherios P. Diamandis, Ioannis Prassas, Douglas D. Fraser

Medical Biophysics Publications

Sport concussions can be difficult to diagnose and if missed, they can expose athletes to greater injury risk and long-lasting neurological disabilities. Discovery of objective biomarkers to aid concussion diagnosis is critical to protecting athlete brain health. To this end, we performed targeted proteomics on plasma obtained from adolescent athletes suffering a sports concussion. A total of 11 concussed male athletes were enrolled at our academic Sport Medicine Concussion Clinic, as well as 24 sex-, age- and activity-matched healthy control subjects. Clinical evaluation was performed and blood was drawn within 72 h of injury. Proximity extension assays were performed for …

Repetitive Mild Traumatic Brain Injury In Mice Triggers A Slowly Developing Cascade Of Long-Term And Persistent Behavioral Deficits And Pathological Changes, Xiaoyun Xu, Matthew Cowan, Flavio Beraldo, Amy Schranz, Patrick Mccunn, Nicole Geremia, Zalman Brown, Maitray Patel, Karen L. Nygard, Reza Khazaee, Lihong Lu, Xingyu Liu, Michael J. Strong, Gregory A. Dekaban, Ravi Menon, Robert Bartha, Mark Daley, Haojie Mao, Vania Prado, Marco A.M. Prado, Lisa Saksida, Tim Bussey, Arthur Brown

Medical Biophysics Publications

We have previously reported long-term changes in the brains of non-concussed varsity rugby players using magnetic resonance spectroscopy (MRS), diffusion tensor imaging (DTI) and functional magnetic imaging (fMRI). Others have reported cognitive deficits in contact sport athletes that have not met the diagnostic criteria for concussion. These results suggest that repetitive mild traumatic brain injuries (rmTBIs) that are not severe enough to meet the diagnostic threshold for concussion, produce long-term consequences. We sought to characterize the neuroimaging, cognitive, pathological and metabolomic changes in a mouse model of rmTBI. Using a closed-skull model of mTBI that when scaled to human leads …

Higher Csf Stnfr1-Related Proteins Associate With Better Prognosis In Very Early Alzheimer’S Disease, William T. Hu, Tugba Ozturk, Alexander Kollhoff, Whitney Wharton, J. Christina Howell, Michael Weiner, Paul Aisen, Ronald Petersen, Clifford R. Jack, William Jagust, John Q. Trojanowki, Arthur W. Toga, Laurel Beckett, Robert C. Green, Andrew J. Saykin, John Morris, Richard J. Perrin, Leslie M. Shaw, Zaven Kachaturian, Maria Carrillo, William Potter, Lisa Barnes, Marie Bernard, Hector González, Carole Ho, John K. Hsiao, Eliezer Masliah, Donna Masterman, Ozioma Okonkwo, Laurie Ryan, Nina Silverberg, Adam Fleisher

Medical Biophysics Publications

Neuroinflammation is associated with Alzheimer’s disease, but the application of cerebrospinal fluid measures of inflammatory proteins may be limited by overlapping pathways and relationships between them. In this work, we measure 15 cerebrospinal proteins related to microglial and T-cell functions, and show them to reproducibly form functionally-related groups within and across diagnostic categories in 382 participants from the Alzheimer’s Disease Neuro-imaging Initiative as well participants from two independent cohorts. We further show higher levels of proteins related to soluble tumor necrosis factor receptor 1 are associated with reduced risk of conversion to dementia in the multi-centered (p = 0.027) and …

Correlation Between Alzheimer’S Disease And Type 2 Diabetes Using Non-Negative Matrix Factorization, Yeonwoo Chung, Hyunju Lee, Michael W. Weiner, Paul Aisen, Ronald Petersen, Cliford R. Jack, William Jagust, John Q. Trojanowki, Arthur W. Toga, Laurel Beckett, Robert C. Green, Andrew J. Saykin, John Morris, Leslie M. Shaw, Zaven Khachaturian, Greg Sorensen, Maria Carrillo, Lew Kuller, Marc Raichle, Steven Paul, Peter Davies, Howard Fillit, Franz Hefti, Davie Holtzman, M. Marcel Mesulam, William Potter, Peter Snyder, Tom Montine, Ronald G. Thomas, Michael Donohue, Sarah Walter, Tamie Sather

Medical Biophysics Publications

Alzheimer’s disease (AD) is a complex and heterogeneous disease that can be affected by various genetic factors. Although the cause of AD is not yet known and there is no treatment to cure this disease, its progression can be delayed. AD has recently been recognized as a brain-specific type of diabetes called type 3 diabetes. Several studies have shown that people with type 2 diabetes (T2D) have a higher risk of developing AD. Therefore, it is important to identify subgroups of patients with AD that may be more likely to be associated with T2D. We here describe a new approach …

Staging Tau Pathology With Tau Pet In Alzheimer’S Disease: A Longitudinal Study, Shi Dong Chen, Jia Ying Lu, Hong Qi Li, Yu Xiang Yang, Jie Hui Jiang, Mei Cui, Chuan Tao Zuo, Lan Tan, Qiang Dong, Jin Tai Yu, Michael W. Weiner, Paul Aisen, Ronald Petersen, Clifford R. Jack, William Jagust, John Q. Trojanowki, Arthur W. Toga, Laurel Beckett, Robert C. Green, Andrew J. Saykin, John C. Morris, Richard J. Perrin, Leslie M. Shaw, Maria Carrillo, William Potter, Lisa Barnes, Marie Bernard, Hector González, Carole Ho, John K. Hsiao, Jonathan Jackson, Eliezer Masliah

Medical Biophysics Publications

A biological research framework to define Alzheimer’ disease with dichotomized biomarker measurement was proposed by National Institute on Aging–Alzheimer’s Association (NIA–AA). However, it cannot characterize the hierarchy spreading pattern of tau pathology. To reflect in vivo tau progression using biomarker, we constructed a refined topographic 18F-AV-1451 tau PET staging scheme with longitudinal clinical validation. Seven hundred and thirty-four participants with baseline 18F-AV-1451 tau PET (baseline age 73.9 ± 7.7 years, 375 female) were stratified into five stages by a topographic PET staging scheme. Cognitive trajectories and clinical progression were compared across stages with or without further dichotomy of amyloid status, …

Author Correction: Spread Of Pathological Tau Proteins Through Communicating Neurons In Human Alzheimer’S Disease (Nature Communications, (2020), 11, 1, (2612), 10.1038/S41467-020-15701-2), Jacob W. Vogel, Yasser Iturria-Medina, Olof T. Strandberg, Ruben Smith, Elizabeth Levitis, Alan C. Evans, Oskar Hansson, Michael Weiner, Paul Aisen, Ronald Petersen, Clifford R. Jack, William Jagust, John Q. Trojanowki, Arthur W. Toga, Laurel Beckett, Robert C. Green, Andrew J. Saykin, John Morris, Leslie M. Shaw, Enchi Liu, Tom Montine, Ronald G. Thomas, Michael Donohue, Sarah Walter, Devon Gessert, Tamie Sather, Gus Jiminez, Danielle Harvey, Michael Donohue, Matthew Bernstein, Nick Fox, Paul Thompson

Medical Biophysics Publications

The original version of the Supplementary information associated with this Article inadvertently omitted Supplementary Table S1. The HTML has been updated to include a corrected version of the Supplementary information.

Plasma Phosphorylated-Tau181 As A Predictive Biomarker For Alzheimer’S Amyloid, Tau And Fdg Pet Status, Xue Ning Shen, Yu Yuan Huang, Shi Dong Chen, Yu Guo, Lan Tan, Qiang Dong, Jin Tai Yu, Michael W. Weiner, Paul Aisen, Ronald Petersen, Clifford R. Jack, William Jagust, John Q. Trojanowki, John Q. Trojanowki, Arthur W. Toga, Laurel Beckett, Robert C. Green, Andrew J. Saykin, John C. Morris, Richard J. Perrin, Leslie M. Shaw, Maria Carrillo, William Potter, Lisa Barnes, Marie Bernard, Hector González, Carole Ho, John K. Hsiao, Jonathan Jackson, Eliezer Masliah, Donna Masterman, Ozioma Okonkwo

Medical Biophysics Publications

Plasma phosphorylated-tau181 (p-tau181) showed the potential for Alzheimer’s diagnosis and prognosis, but its role in detecting cerebral pathologies is unclear. We aimed to evaluate whether it could serve as a marker for Alzheimer’s pathology in the brain. A total of 1189 participants with plasma p-tau181 and PET data of amyloid, tau or FDG PET were included from ADNI. Cross-sectional relationships of plasma p-tau181 with PET biomarkers were tested. Longitudinally, we further investigated whether different p-tau181 levels at baseline predicted different progression of Alzheimer’s pathological changes in the brain. We found plasma p-tau181 significantly correlated with brain amyloid (Spearman ρ = …

Early Protein Intake Predicts Functional Connectivity And Neurocognition In Preterm Born Children, Emma G. Duerden, Benjamin Thompson, Tanya Poppe, Jane Alsweiler, Greg Gamble, Yannan Jiang, Myra Leung, Anna C. Tottman, Trecia Wouldes, Steven P. Miller, Jane E. Harding, Jane M. Alsweiler, Janene B. Biggs, Coila Bevan, Joanna M. Black, Frank H. Bloomfield, Kelly Fredell, Greg D. Gamble, Jane E. Harding, Sabine Huth, Yannan Jiang, Christine Kevan, Myra Leung, Geraint Phillips, Tanya Poppe, Jennifer A. Rogers, Heather Stewart, Benjamin S. Thompson

Brain and Mind Institute Researchers' Publications

© 2021, The Author(s). Nutritional intake can promote early neonatal brain development in very preterm born neonates (< 32 weeks’ gestation). In a group of 7-year-old very preterm born children followed since birth, we examined whether early nutrient intake in the first weeks of life would be associated with long-term brain function and neurocognitive skills at school age. Children underwent resting-state functional MRI (fMRI), intelligence testing (Wechsler Intelligence Scale for Children, 5th Ed) and visual-motor processing (Beery-Buktenica, 5th Ed) at 7 years. Relationships were assessed between neonatal macronutrient intakes, functional connectivity strength between thalamic and default mode networks (DMN), and neuro-cognitive function using multivariable regression. Greater functional connectivity strength between thalamic networks and DMN was associated with greater intake of protein in the first week (β = 0.17; 95% CI 0.11, 0.23, p < 0.001) but lower intakes of fat (β = − 0.06; 95% CI − 0.09, − 0.02, p = 0.001) and carbohydrates (β = − 0.03; 95% CI − 0.04, − 0.01, p = 0.003). Connectivity strength was also associated with protein intake during the first month (β = 0.22; 95% CI 0.06, 0.37, p = 0.006). Importantly, greater thalamic-DMN connectivity strength was associated with higher processing speed indices (β = 26.9; 95% CI 4.21, 49.49, p = 0.02) and visual processing scores (β = 9.03; 95% CI 2.27, 15.79, p = 0.009). Optimizing early protein intake may contribute to promoting long-term brain health in preterm-born children.

Magnetic Resonance Imaging Sequence Identification Using A Metadata Learning Approach, Shuai Liang, Derek Beaton, Stephen R. Arnott, Tom Gee, Mojdeh Zamyadi, Robert Bartha, Sean Symons, Glenda M. Macqueen, Stefanie Hassel, Jason P. Lerch, Evdokia Anagnostou, Raymond W. Lam, Benicio N. Frey, Roumen Milev, Daniel J. Müller, Sidney H. Kennedy, Christopher J.M. Scott, Stephen C. Strother

Medical Biophysics Publications

Despite the wide application of the magnetic resonance imaging (MRI) technique, there are no widely used standards on naming and describing MRI sequences. The absence of consistent naming conventions presents a major challenge in automating image processing since most MRI software require a priori knowledge of the type of the MRI sequences to be processed. This issue becomes increasingly critical with the current efforts toward open-sharing of MRI data in the neuroscience community. This manuscript reports an MRI sequence detection method using imaging metadata and a supervised machine learning technique. Three datasets from the Brain Center for Ontario Data Exploration …

Musical Instrument Familiarity Affects Statistical Learning Of Tone Sequences., Stephen C Van Hedger, Ingrid Johnsrude, Laura J Batterink

Brain and Mind Institute Researchers' Publications

Most listeners have an implicit understanding of the rules that govern how music unfolds over time. This knowledge is acquired in part through statistical learning, a robust learning mechanism that allows individuals to extract regularities from the environment. However, it is presently unclear how this prior musical knowledge might facilitate or interfere with the learning of novel tone sequences that do not conform to familiar musical rules. In the present experiment, participants listened to novel, statistically structured tone sequences composed of pitch intervals not typically found in Western music. Between participants, the tone sequences either had the timbre of artificial, …

Family Functioning As A Moderator In The Relation Between Perceived Stress And Psychotic-Like Experiences Among Adolescents During Covid-19, Zhipeng Wu, Zhulin Zou, Feiwen Wang, Zhibiao Xiang, Mengran Zhu, Yicheng Long, Haojuan Tao, Lena Palaniyappan, Zhening Liu

Brain and Mind Institute Researchers' Publications

Background: The COVID-19 pandemic has increased psychological stress among adolescents, and the relation between perceived stress (PS) and psychotic-like experiences (PLEs) has been well-established. However, little is known about the role of family functioning (FF) in this relation, especially when adolescents experienced the extended lockdown period with family members. Methods: A total of 4807 adolescents completed this retrospective paper-and-pencil survey after school reopening between May 14th and June 6th, 2020 in Hunan Province, China. We measured PS with the Perceived stress scale (PSS-10), PLEs with the eight positive items from Community Assessment of Psychic Experiences (CAPE-8), and FF with the …

Improved Segmentation Of The Intracranial And Ventricular Volumes In Populations With Cerebrovascular Lesions And Atrophy Using 3d Cnns, Emmanuel E. Ntiri, Melissa F. Holmes, Parisa M. Forooshani, Joel Ramirez, Fuqiang Gao, Miracle Ozzoude, Sabrina Adamo, Christopher J.M. Scott, Dar Dowlatshahi, Jane M. Lawrence-Dewar, Donna Kwan, Anthony E. Lang, Sean Symons, Robert Bartha, Stephen Strother, Jean Claude Tardif, Mario Masellis, Richard H. Swartz, Alan Moody, Sandra E. Black, Maged Goubran

Medical Biophysics Publications

Successful segmentation of the total intracranial vault (ICV) and ventricles is of critical importance when studying neurodegeneration through neuroimaging. We present iCVMapper and VentMapper, robust algorithms that use a convolutional neural network (CNN) to segment the ICV and ventricles from both single and multi-contrast MRI data. Our models were trained on a large dataset from two multi-site studies (N = 528 subjects for ICV, N = 501 for ventricular segmentation) consisting of older adults with varying degrees of cerebrovascular lesions and atrophy, which pose significant challenges for most segmentation approaches. The models were tested on 238 participants, including subjects with …

Regional Brain And Spinal Cord Volume Loss In Spinocerebellar Ataxia Type 3, Jennifer Faber, Tamara Schaprian, Koyak Berkan, Kathrin Reetz, Marcondes Cavalcante França, Thiago Junqueira Ribeiro De Rezende, Jiang Hong, Weihua Liao, Bart Van De Warrenburg, Judith Van Gaalen, Alexandra Durr, Fanny Mochel, Paola Giunti, Hector Garcia-Moreno, Ludger Schoels, Holger Hengel, Matthis Synofzik, Benjamin Bender, Gulin Oz, James Joers, Jereon J. De Vries, Jun Suk Kang, Dagmar Timmann-Braun, Heike Jacobi, Jon Infante, Richard Joules, Sandro Romanzetti, Jorn Diedrichsen, Matthias Schmid, Robin Wolz, Thomas Klockgether

Brain and Mind Institute Researchers' Publications

Background: Given that new therapeutic options for spinocerebellar ataxias are on the horizon, there is a need for markers that reflect disease-related alterations, in particular, in the preataxic stage, in which clinical scales are lacking sensitivity. Objective: The objective of this study was to quantify regional brain volumes and upper cervical spinal cord areas in spinocerebellar ataxia type 3 in vivo across the entire time course of the disease. Methods: We applied a brain segmentation approach that included a lobular subsegmentation of the cerebellum to magnetic resonance images of 210 ataxic and 48 preataxic spinocerebellar ataxia type 3 mutation carriers …

Functional Organization Of Frontoparietal Cortex In The Marmoset Investigated With Awake Resting-State Fmri, Yuki Hori, Justine C. Cléry, David J. Schaeffer, Ravi S. Menon, Stefan Everling

Brain and Mind Institute Researchers' Publications

Frontoparietal networks contribute to complex cognitive functions in humans and macaques, such as working memory, attention, task-switching, response suppression, grasping, reaching, and eye movement control. However, there has been no comprehensive examination of the functional organization of frontoparietal networks using functional magnetic resonance imaging in the New World common marmoset monkey (Callithrix jacchus), which is now widely recognized as a powerful nonhuman primate experimental animal. In this study, we employed hierarchical clustering of interareal blood oxygen level-dependent signals to investigate the hypothesis that the organization of the frontoparietal cortex in the marmoset follows the organizational principles of the macaque frontoparietal …

Sustained Neural Activity Correlates With Rapid Perceptual Learning Of Auditory Patterns, Björn Herrmann, Kurdo Araz, Ingrid S. Johnsrude

Brain and Mind Institute Researchers' Publications

Repeating structures forming regular patterns are common in sounds. Learning such patterns may enable accurate perceptual organization. In five experiments, we investigated the behavioral and neural signatures of rapid perceptual learning of regular sound patterns. We show that recurring (compared to novel) patterns are detected more quickly and increase sensitivity to pattern deviations and to the temporal order of pattern onset relative to a visual stimulus. Sustained neural activity reflected perceptual learning in two ways. Firstly, sustained activity increased earlier for recurring than novel patterns when participants attended to sounds, but not when they ignored them; this earlier increase mirrored …

Nnresting State Fmri Scanner Instabilities Revealed By Longitud Inal Phantom Scans In A Multi-Center Study, Aras Kayvanrad, Stephen R. Arnott, Nathan Churchill, Stefanie Hassel, Aditi Chemparathy, Fan Dong, Mojdeh Zamyadi, Tom Gee, Robert Bartha, Sandra E. Black, Jane M. Lawrence-Dewar, Christopher J.M. Scott, Sean Symons, Andrew D. Davis, Geoffrey B. Hall, Jacqueline Harris, Nancy J. Lobaugh, Glenda Macqueen, Cindy Woo, Stephen Strother

Medical Biophysics Publications

Quality assurance (QA) is crucial in longitudinal and/or multi-site studies, which involve the collection of data from a group of subjects over time and/or at different locations. It is important to regularly monitor the performance of the scanners over time and at different locations to detect and control for intrinsic differences (e.g., due to manufacturers) and changes in scanner performance (e.g., due to gradual component aging, software and/or hardware upgrades, etc.). As part of the Ontario Neurodegenerative Disease Research Initiative (ONDRI) and the Canadian Biomarker Integration Network in Depression (CAN-BIND), QA phantom scans were conducted approximately monthly for three to …

A Novel Three-Choice Touchscreen Task To Examine Spatial Attention And Orienting Responses In Rodents, Faraj L. Haddad, Maryam Ghahremani, Cleusa De Oliveira, Ella E. Doornaert, Kevin D. Johnston, Stefan Everling, Susanne Schmid

Brain and Mind Institute Researchers' Publications

Mammalian orienting behavior consists of coordinated movements of the eyes, head, pinnae, vibrissae, or body to attend to an external stimulus. The present study aimed to develop a novel operant task using a touch-screen system to measure spatial attention. In this task, rats were trained to nose-poke a light stimulus presented in one of three locations. The stimulus was presented more frequently in the center location to develop spatial attention bias toward the center stimulus. Changes in orienting responses were detected by measuring the animals’ response accuracy and latency to stimuli at the lateral locations, following reversible unilateral chemogenetic inactivation …