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Articles 61 - 90 of 714

Full-Text Articles in Medical Sciences

High-Contrast, Moving Targets In An Emerging Target Paradigm Promote Fast Visuomotor Responses During Visually Guided Reaching, Rebecca A. Kozak, Brian D. Corneil Jan 2021

High-Contrast, Moving Targets In An Emerging Target Paradigm Promote Fast Visuomotor Responses During Visually Guided Reaching, Rebecca A. Kozak, Brian D. Corneil

Brain and Mind Institute Researchers' Publications

Humans have a remarkable capacity to rapidly interact with the surrounding environment, often by transforming visual input into motor output on a moment-to-moment basis. But what visual features promote rapid reaching? High-contrast, fast-moving targets elicit strong responses in the superior colliculus (SC), a structure associated with express saccades and implicated in rapid electromyographic (EMG) responses on upper limb muscles. To test the influence of stimulus properties on rapid reaches, we had human subjects perform visually guided reaches to moving targets varied by speed (experiment 1) or speed and contrast (experiment 2) in an emerging target paradigm that has recently been …

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Intelligibility Benefit For Familiar Voices Does Not Depend On Better Discrimination Of Fundamental Frequency Or Vocal Tract Length, Emma Holmes, Ingrid Johnsrude Jan 2021

Intelligibility Benefit For Familiar Voices Does Not Depend On Better Discrimination Of Fundamental Frequency Or Vocal Tract Length, Emma Holmes, Ingrid Johnsrude

Brain and Mind Institute Researchers' Publications

Speech is more intelligible when it is spoken by familiar than unfamiliar people. Two cues to voice identity are glottal pulse rate (GPR) and vocal tract length (VTL): perhaps these features are more accurately represented for familiar voices in a listener’s brain. If so, listeners should be able to discriminate smaller manipulations to perceptual correlates of these vocal parameters for familiar than unfamiliar voices. We recruited pairs of friends who had known each other for 0.5–22.5 years. We measured thresholds for discriminating pitch (correlate of GPR) and formant spacing (correlate of VTL; ‘VTL-timbre’) for voices that were familiar (friends) and …

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The Role Of Haptic Expectations In Reaching To Grasp: From Pantomime To Natural Grasps And Back Again, Robert L. Whitwell, Nathan J. Katz, Melvyn A. Goodale, James T. Enns Dec 2020

The Role Of Haptic Expectations In Reaching To Grasp: From Pantomime To Natural Grasps And Back Again, Robert L. Whitwell, Nathan J. Katz, Melvyn A. Goodale, James T. Enns

Brain and Mind Institute Researchers' Publications

© Copyright © 2020 Whitwell, Katz, Goodale and Enns. When we reach to pick up an object, our actions are effortlessly informed by the object’s spatial information, the position of our limbs, stored knowledge of the object’s material properties, and what we want to do with the object. A substantial body of evidence suggests that grasps are under the control of “automatic, unconscious” sensorimotor modules housed in the “dorsal stream” of the posterior parietal cortex. Visual online feedback has a strong effect on the hand’s in-flight grasp aperture. Previous work of ours exploited this effect to show that grasps are …

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Case – 18F-Dcfpyl-Positron Emission Tomography/Computed Tomography (Pet/Ct) Time Of Imaging, Golmehr Sistani, Ur Metser, Glenn S. Bauman, David T. Laidley, Stephen E. Pautler, Katherine A. Zukotynski Dec 2020

Case – 18F-Dcfpyl-Positron Emission Tomography/Computed Tomography (Pet/Ct) Time Of Imaging, Golmehr Sistani, Ur Metser, Glenn S. Bauman, David T. Laidley, Stephen E. Pautler, Katherine A. Zukotynski

Medical Biophysics Publications

No abstract provided.

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Cortical Thickness Estimation In Individuals With Cerebral Small Vessel Disease, Focal Atrophy, And Chronic Stroke Lesions, Miracle Ozzoude, Joel Ramirez, Pradeep Reddy Raamana, Melissa F. Holmes, Kirstin Walker, Christopher J.M. Scott, Fuqiang Gao, Maged Goubran, Donna Kwan, Maria C. Tartaglia, Derek Beaton, Gustavo Saposnik, Ayman Hassan, Jane Lawrence-Dewar, Dariush Dowlatshahi, Stephen C. Strother, Sean Symons, Robert Bartha, Richard H. Swartz, Sandra E. Black Dec 2020

Cortical Thickness Estimation In Individuals With Cerebral Small Vessel Disease, Focal Atrophy, And Chronic Stroke Lesions, Miracle Ozzoude, Joel Ramirez, Pradeep Reddy Raamana, Melissa F. Holmes, Kirstin Walker, Christopher J.M. Scott, Fuqiang Gao, Maged Goubran, Donna Kwan, Maria C. Tartaglia, Derek Beaton, Gustavo Saposnik, Ayman Hassan, Jane Lawrence-Dewar, Dariush Dowlatshahi, Stephen C. Strother, Sean Symons, Robert Bartha, Richard H. Swartz, Sandra E. Black

Medical Biophysics Publications

Background: Regional changes to cortical thickness in individuals with neurodegenerative and cerebrovascular diseases (CVD) can be estimated using specialized neuroimaging software. However, the presence of cerebral small vessel disease, focal atrophy, and cortico-subcortical stroke lesions, pose significant challenges that increase the likelihood of misclassification errors and segmentation failures. Purpose: The main goal of this study was to examine a correction procedure developed for enhancing FreeSurfer’s (FS’s) cortical thickness estimation tool, particularly when applied to the most challenging MRI obtained from participants with chronic stroke and CVD, with varying degrees of neurovascular lesions and brain atrophy. Methods: In 155 CVD participants …

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Pathway‐Extended Gene Expression Signatures Integrate Novel Biomarkers That Improve Predictions Of Patient Responses To Kinase Inhibitors, Ashis Bagchee‐Clark, Eliseos J. Mucaki, Tyson Whitehead, Peter Rogan Dec 2020

Pathway‐Extended Gene Expression Signatures Integrate Novel Biomarkers That Improve Predictions Of Patient Responses To Kinase Inhibitors, Ashis Bagchee‐Clark, Eliseos J. Mucaki, Tyson Whitehead, Peter Rogan

Biochemistry Publications

Cancer chemotherapy responses have been related to multiple pharmacogenetic biomarkers, often for the same drug. This study utilizes machine learning to derive multi‐gene expression signatures that predict individual patient responses to specific tyrosine kinase inhibitors, including erlotinib, gefitinib, sorafenib, sunitinib, lapatinib and imatinib. Support vector machine (SVM) learning was used to train mathematical models that distinguished sensitivity from resistance to these drugs using a novel systems biology‐based approach. This began with expression of genes previously implicated in specific drug responses, then expanded to evaluate genes whose products were related through biochemical pathways and interactions. Optimal pathway‐extended SVMs predicted responses in …

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Histologic Tissue Components Provide Major Cues For Machine Learning-Based Prostate Cancer Detection And Grading On Prostatectomy Specimens, Wenchao Han, Carol Johnson, Mena Gaed, José A. Gómez, Madeleine Moussa, Joseph L. Chin, Stephen Pautler, Glenn S. Bauman, Aaron D. Ward Dec 2020

Histologic Tissue Components Provide Major Cues For Machine Learning-Based Prostate Cancer Detection And Grading On Prostatectomy Specimens, Wenchao Han, Carol Johnson, Mena Gaed, José A. Gómez, Madeleine Moussa, Joseph L. Chin, Stephen Pautler, Glenn S. Bauman, Aaron D. Ward

Medical Biophysics Publications

Automatically detecting and grading cancerous regions on radical prostatectomy (RP) sections facilitates graphical and quantitative pathology reporting, potentially benefitting post-surgery prognosis, recurrence prediction, and treatment planning after RP. Promising results for detecting and grading prostate cancer on digital histopathology images have been reported using machine learning techniques. However, the importance and applicability of those methods have not been fully investigated. We computed three-class tissue component maps (TCMs) from the images, where each pixel was labeled as nuclei, lumina, or other. We applied seven different machine learning approaches: three non-deep learning classifiers with features extracted from TCMs, and four deep learning, …

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A Telescope Gwas Analysis Strategy, Based On Snps-Genes-Pathways Ensamble And On Multivariate Algorithms, To Characterize Late Onset Alzheimer’S Disease, Margherita Squillario, Giulia Abate, Federico Tomasi, Veronica Tozzo, Annalisa Barla, Daniela Uberti, Michael W. Weiner, Paul Aisen, Ronald Petersen, Jack R. Clifford, 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 Dec 2020

A Telescope Gwas Analysis Strategy, Based On Snps-Genes-Pathways Ensamble And On Multivariate Algorithms, To Characterize Late Onset Alzheimer’S Disease, Margherita Squillario, Giulia Abate, Federico Tomasi, Veronica Tozzo, Annalisa Barla, Daniela Uberti, Michael W. Weiner, Paul Aisen, Ronald Petersen, Jack R. Clifford, 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

Medical Biophysics Publications

Genome–wide association studies (GWAS) have revealed a plethora of putative susceptibility genes for Alzheimer’s disease (AD), with the sole exception of APOE gene unequivocally validated in independent study. Considering that the etiology of complex diseases like AD could depend on functional multiple genes interaction network, here we proposed an alternative GWAS analysis strategy based on (i) multivariate methods and on a (ii) telescope approach, in order to guarantee the identification of correlated variables, and reveal their connections at three biological connected levels. Specifically as multivariate methods, we employed two machine learning algorithms and a genetic association test and we considered …

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Challenges And Opportunities With Causal Discovery Algorithms: Application To Alzheimer’S Pathophysiology, Xinpeng Shen, Sisi Ma, Prashanthi Vemuri, Gyorgy Simon, Michael W. Weiner, Paul Aisen, Ronald Petersen, Clifford R. Jack, Andrew J. Saykin, William Jagust, John Q. Trojanowki, Arthur W. Toga, Laurel Beckett, Robert C. Green, John Morris, Leslie M. Shaw, Zaven Khachaturian, Greg Sorensen, Maria Carrillo, Lew Kuller, Marc Raichle, Steven Paul, Peter Davies, Howard Fillit, Franz Hefti, David Holtzman, M. Marcel Mesulam, William Potter, Peter Snyder, Adam Schwartz, Tom Montine, Ronald G. Thomas Dec 2020

Challenges And Opportunities With Causal Discovery Algorithms: Application To Alzheimer’S Pathophysiology, Xinpeng Shen, Sisi Ma, Prashanthi Vemuri, Gyorgy Simon, Michael W. Weiner, Paul Aisen, Ronald Petersen, Clifford R. Jack, Andrew J. Saykin, William Jagust, John Q. Trojanowki, Arthur W. Toga, Laurel Beckett, Robert C. Green, John Morris, Leslie M. Shaw, Zaven Khachaturian, Greg Sorensen, Maria Carrillo, Lew Kuller, Marc Raichle, Steven Paul, Peter Davies, Howard Fillit, Franz Hefti, David Holtzman, M. Marcel Mesulam, William Potter, Peter Snyder, Adam Schwartz, Tom Montine, Ronald G. Thomas

Medical Biophysics Publications

Causal Structure Discovery (CSD) is the problem of identifying causal relationships from large quantities of data through computational methods. With the limited ability of traditional association-based computational methods to discover causal relationships, CSD methodologies are gaining popularity. The goal of the study was to systematically examine whether (i) CSD methods can discover the known causal relationships from observational clinical data and (ii) to offer guidance to accurately discover known causal relationships. We used Alzheimer’s disease (AD), a complex progressive disease, as a model because the well-established evidence provides a “gold-standard” causal graph for evaluation. We evaluated two CSD methods, Fast …

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Fam222a Encodes A Protein Which Accumulates In Plaques In Alzheimer’S Disease, Tingxiang Yan, Jingjing Liang, Ju Gao, Luwen Wang, Hisashi Fujioka, Michael W. Weiner, Norbert Schuff, Howard J. Rosen, Bruce L. Miller, David Perry, Paul Aisen, Paul Aisen, Arthur W. Toga, Gustavo Jimenez, Michael Donohue, Devon Gessert, Kelly Harless, Jennifer Salazar, Yuliana Cabrera, Sarah Walter, Lindsey Hergesheimer, Arthur W. Toga, Karen Crawford, Scott Neu, Lon S. Schneider, Sonia Pawluczyk, Mauricio Becerra, Liberty Teodoro, Bryan M. Spann, Ronald Petersen, Clifford R. Jack, Matthew Bernstein Dec 2020

Fam222a Encodes A Protein Which Accumulates In Plaques In Alzheimer’S Disease, Tingxiang Yan, Jingjing Liang, Ju Gao, Luwen Wang, Hisashi Fujioka, Michael W. Weiner, Norbert Schuff, Howard J. Rosen, Bruce L. Miller, David Perry, Paul Aisen, Paul Aisen, Arthur W. Toga, Gustavo Jimenez, Michael Donohue, Devon Gessert, Kelly Harless, Jennifer Salazar, Yuliana Cabrera, Sarah Walter, Lindsey Hergesheimer, Arthur W. Toga, Karen Crawford, Scott Neu, Lon S. Schneider, Sonia Pawluczyk, Mauricio Becerra, Liberty Teodoro, Bryan M. Spann, Ronald Petersen, Clifford R. Jack, Matthew Bernstein

Medical Biophysics Publications

Alzheimer’s disease (AD) is characterized by amyloid plaques and progressive cerebral atrophy. Here, we report FAM222A as a putative brain atrophy susceptibility gene. Our cross-phenotype association analysis of imaging genetics indicates a potential link between FAM222A and AD-related regional brain atrophy. The protein encoded by FAM222A is predominantly expressed in the CNS and is increased in brains of patients with AD and in an AD mouse model. It accumulates within amyloid deposits, physically interacts with amyloid-β (Aβ) via its N-terminal Aβ binding domain, and facilitates Aβ aggregation. Intracerebroventricular infusion or forced expression of this protein exacerbates neuroinflammation and cognitive dysfunction …

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Social Cognition Impairment In Genetic Frontotemporal Dementia Within The Genfi Cohort, Lucy L. Russell, Caroline V. Greaves, Martina Bocchetta, Jennifer Nicholas, Rhian S. Convery, Katrina Moore, David M. Cash, John Van Swieten, Lize Jiskoot, Fermin Moreno, Raquel Sanchez-Valle, Barbara Borroni, Robert Laforce, Mario Masellis, Maria Carmela Tartaglia, Caroline Graff, Emanuela Rotondo, Daniela Galimberti, James B. Rowe, Elizabeth Finger, Matthis Synofzik, Rik Vandenberghe, Alexandre De Mendonça, Fabrizio Tagliavini, Isabel Santana, Simon Ducharme, Chris Butler, Alex Gerhard, Johannes Levin, Adrian Danek, Markus Otto, Jason D. Warren Dec 2020

Social Cognition Impairment In Genetic Frontotemporal Dementia Within The Genfi Cohort, Lucy L. Russell, Caroline V. Greaves, Martina Bocchetta, Jennifer Nicholas, Rhian S. Convery, Katrina Moore, David M. Cash, John Van Swieten, Lize Jiskoot, Fermin Moreno, Raquel Sanchez-Valle, Barbara Borroni, Robert Laforce, Mario Masellis, Maria Carmela Tartaglia, Caroline Graff, Emanuela Rotondo, Daniela Galimberti, James B. Rowe, Elizabeth Finger, Matthis Synofzik, Rik Vandenberghe, Alexandre De Mendonça, Fabrizio Tagliavini, Isabel Santana, Simon Ducharme, Chris Butler, Alex Gerhard, Johannes Levin, Adrian Danek, Markus Otto, Jason D. Warren

Medical Biophysics Publications

A key symptom of frontotemporal dementia (FTD) is difficulty interacting socially with others. Social cognition problems in FTD include impaired emotion processing and theory of mind difficulties, and whilst these have been studied extensively in sporadic FTD, few studies have investigated them in familial FTD. Facial Emotion Recognition (FER) and Faux Pas (FP) recognition tests were used to study social cognition within the Genetic Frontotemporal Dementia Initiative (GENFI), a large familial FTD cohort of C9orf72, GRN, and MAPT mutation carriers. 627 participants undertook at least one of the tasks, and were separated into mutation-negative healthy controls, presymptomatic mutation carriers (split …

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Coexistence Of Perseveration And Apathy In The Tdp-43Q331k Knock-In Mouse Model Of Als–Ftd, Eosu Kim, Matthew A. White, Benjamin U. Phillips, Laura Lopez-Cruz, Hyunjeong Kim, Christopher J. Heath, Jong Eun Lee, Lisa M. Saksida, Jemeen Sreedharan, Timothy J. Bussey Dec 2020

Coexistence Of Perseveration And Apathy In The Tdp-43Q331k Knock-In Mouse Model Of Als–Ftd, Eosu Kim, Matthew A. White, Benjamin U. Phillips, Laura Lopez-Cruz, Hyunjeong Kim, Christopher J. Heath, Jong Eun Lee, Lisa M. Saksida, Jemeen Sreedharan, Timothy J. Bussey

Brain and Mind Institute Researchers' Publications

© 2020, The Author(s). Perseveration and apathy are two of the most common behavioural and psychological symptoms of dementia (BPSDs) in amyotrophic lateral sclerosis–frontotemporal dementia (ALS–FTD). Availability of a validated and behaviourally characterised animal model is crucial for translational research into BPSD in the FTD context. We behaviourally evaluated the male TDP-43Q331K mouse, an ALS–FTD model with a human-equivalent mutation (TDP-43Q331K) knocked into the endogenous Tardbp gene. We utilised a panel of behavioural tasks delivered using the rodent touchscreen apparatus, including progressive ratio (PR), extinction and visual discrimination/reversal learning (VDR) assays to examine motivation, response inhibition and cognitive flexibility, respectively. …

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Face Selective Patches In Marmoset Frontal Cortex, David J. Schaeffer, Janahan Selvanayagam, Kevin D. Johnston, Ravi S. Menon, Winrich A. Freiwald, Stefan Everling Dec 2020

Face Selective Patches In Marmoset Frontal Cortex, David J. Schaeffer, Janahan Selvanayagam, Kevin D. Johnston, Ravi S. Menon, Winrich A. Freiwald, Stefan Everling

Brain and Mind Institute Researchers' Publications

© 2020, The Author(s). In humans and macaque monkeys, socially relevant face processing is accomplished via a distributed functional network that includes specialized patches in frontal cortex. It is unclear whether a similar network exists in New World primates, who diverged ~35 million years from Old World primates. The common marmoset is a New World primate species ideally placed to address this question given their complex social repertoire. Here, we demonstrate the existence of a putative high-level face processing network in marmosets. Like Old World primates, marmosets show differential activation in anterior cingulate and lateral prefrontal cortices while they view …

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Shared Functional Connectivity Between The Dorso-Medial And Dorso-Ventral Streams In Macaques, R. Stefan Greulich, Ramina Adam, Stefan Everling, Hansjörg Scherberger Dec 2020

Shared Functional Connectivity Between The Dorso-Medial And Dorso-Ventral Streams In Macaques, R. Stefan Greulich, Ramina Adam, Stefan Everling, Hansjörg Scherberger

Brain and Mind Institute Researchers' Publications

© 2020, The Author(s). Manipulation of an object requires us to transport our hand towards the object (reach) and close our digits around that object (grasp). In current models, reach-related information is propagated in the dorso-medial stream from posterior parietal area V6A to medial intraparietal area, dorsal premotor cortex, and primary motor cortex. Grasp-related information is processed in the dorso-ventral stream from the anterior intraparietal area to ventral premotor cortex and the hand area of primary motor cortex. However, recent studies have cast doubt on the validity of this separation in separate processing streams. We investigated in 10 male rhesus …

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Neural Responses And Perceptual Sensitivity To Sound Depend On Sound-Level Statistics, Björn Herrmann, Thomas Augereau, Ingrid S. Johnsrude Dec 2020

Neural Responses And Perceptual Sensitivity To Sound Depend On Sound-Level Statistics, Björn Herrmann, Thomas Augereau, Ingrid S. Johnsrude

Brain and Mind Institute Researchers' Publications

© 2020, The Author(s). Sensitivity to sound-level statistics is crucial for optimal perception, but research has focused mostly on neurophysiological recordings, whereas behavioral evidence is sparse. We use electroencephalography (EEG) and behavioral methods to investigate how sound-level statistics affect neural activity and the detection of near-threshold changes in sound amplitude. We presented noise bursts with sound levels drawn from distributions with either a low or a high modal sound level. One participant group listened to the stimulation while EEG was recorded (Experiment I). A second group performed a behavioral amplitude-modulation detection task (Experiment II). Neural activity depended on sound-level statistical …

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A Novel Approach To Investigate Subcortical And Cortical Sensitivity To Temporal Structure Simultaneously, Sonia Yasmin, David W. Purcell, Sangamanatha A. Veeranna, Ingrid S. Johnsrude, Björn Herrmann Dec 2020

A Novel Approach To Investigate Subcortical And Cortical Sensitivity To Temporal Structure Simultaneously, Sonia Yasmin, David W. Purcell, Sangamanatha A. Veeranna, Ingrid S. Johnsrude, Björn Herrmann

Brain and Mind Institute Researchers' Publications

Hearing loss is associated with changes at the peripheral, subcortical, and cortical auditory stages. Research often focuses on these stages in isolation, but peripheral damage has cascading effects on central processing, and different stages are interconnected through extensive feedforward and feedback projections. Accordingly, assessment of the entire auditory system is needed to understand auditory pathology. Using a novel stimulus paired with electroencephalography in young, normal-hearing adults, we assess neural function at multiple stages of the auditory pathway simultaneously. We employ click trains that repeatedly accelerate then decelerate (3.5 Hz click-rate-modulation) introducing varying inter-click-intervals (4 to 40 ms). We measured the …

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Modeling An Auditory Stimulated Brain Under Altered States Of Consciousness Using The Generalized Ising Model, Sivayini Kandeepan, Jorge Rudas, Francisco Gomez, Bobby Stojanoski, Sree Ram Valluri, Adrian Mark Owen, Lorina Naci, Emily Sophia Nichols, Andrea Soddu Dec 2020

Modeling An Auditory Stimulated Brain Under Altered States Of Consciousness Using The Generalized Ising Model, Sivayini Kandeepan, Jorge Rudas, Francisco Gomez, Bobby Stojanoski, Sree Ram Valluri, Adrian Mark Owen, Lorina Naci, Emily Sophia Nichols, Andrea Soddu

Brain and Mind Institute Researchers' Publications

Propofol is a short-acting medication that results in decreased levels of consciousness and is used for general anesthesia. Although it is the most commonly used anesthetic in the world, much remains unknown about the mechanisms by which it induces a loss of consciousness. Characterizing anesthesia-induced alterations to brain network activity might provide a powerful framework for understanding the neural mechanisms of unconsciousness. The aim of this work was to model brain activity in healthy brains during various stages of consciousness, as induced by propofol, in the auditory paradigm. We used the generalized Ising model (GIM) to fit the empirical fMRI …

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Optimization Of Multi-Electrode Implant Configurations And Programming For The Delivery Of Non-Ablative Electric Fields In Intratumoral Modulation Therapy., Erin Iredale, Andrew Deweyert, Douglas A Hoover, Jeff Z Chen, Susanne Schmid, Matthew O Hebb, Terry M Peters, Eugene Wong Nov 2020

Optimization Of Multi-Electrode Implant Configurations And Programming For The Delivery Of Non-Ablative Electric Fields In Intratumoral Modulation Therapy., Erin Iredale, Andrew Deweyert, Douglas A Hoover, Jeff Z Chen, Susanne Schmid, Matthew O Hebb, Terry M Peters, Eugene Wong

Medical Biophysics Publications

PURPOSE: Application of low intensity electric fields to interfere with tumor growth is being increasingly recognized as a promising new cancer treatment modality. Intratumoral modulation therapy (IMT) is a developing technology that uses multiple electrodes implanted within or adjacent tumor regions to deliver electric fields to treat cancer. In this study, the determination of optimal IMT parameters was cast as a mathematical optimization problem, and electrode configurations, programming, optimization, and maximum treatable tumor size were evaluated in the simplest and easiest to understand spherical tumor model. The establishment of electrode placement and programming rules to maximize electric field tumor coverage …

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Brain Metabolite Levels In Sedentary Women And Non-Contact Athletes Differ From Contact Athletes, Amy L. Schranz, Gregory A. Dekaban, Lisa Fischer, Kevin Blackney, Christy Barreira, Timothy J. Doherty, Douglas D. Fraser, Arthur Brown, Jeff Holmes, Ravi S. Menon, Robert Bartha Nov 2020

Brain Metabolite Levels In Sedentary Women And Non-Contact Athletes Differ From Contact Athletes, Amy L. Schranz, Gregory A. Dekaban, Lisa Fischer, Kevin Blackney, Christy Barreira, Timothy J. Doherty, Douglas D. Fraser, Arthur Brown, Jeff Holmes, Ravi S. Menon, Robert Bartha

Brain and Mind Institute Researchers' Publications

White matter tracts are known to be susceptible to injury following concussion. The objective of this study was to determine whether contact play in sport could alter white matter metabolite levels in female varsity athletes independent of changes induced by long-term exercise. Metabolite levels were measured by single voxel proton magnetic resonance spectroscopy (MRS) in the prefrontal white matter at the beginning (In-Season) and end (Off-Season) of season in contact (N = 54, rugby players) and non-contact (N = 23, swimmers and rowers) varsity athletes. Sedentary women (N = 23) were scanned once, at a time equivalent to the Off-Season …

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Structure Of Population Activity In Primary Motor Cortex For Single Finger Flexion And Extension, Spencer A. Arbuckle, Jeff Weiler, Eric A. Kirk, Charles L. Rice, Marc Schieber, J. Andrew Pruszynski, Naveed Ejaz, Jörn Diedrichsen Nov 2020

Structure Of Population Activity In Primary Motor Cortex For Single Finger Flexion And Extension, Spencer A. Arbuckle, Jeff Weiler, Eric A. Kirk, Charles L. Rice, Marc Schieber, J. Andrew Pruszynski, Naveed Ejaz, Jörn Diedrichsen

Brain and Mind Institute Researchers' Publications

Copyright © 2020 the authors How is the primary motor cortex (M1) organized to control fine finger movements? We investigated the population activity in M1 for single finger flexion and extension, using 7T functional magnetic resonance imaging (fMRI) in female and male human participants and compared these results to the neural spiking patterns recorded in two male monkeys performing the identical task. fMRI activity patterns were distinct for movements of different fingers, but were quite similar for flexion and extension of the same finger. In contrast, spiking patterns in monkeys were quite distinct for both fingers and directions, which is …

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Cortico-Subcortical Functional Connectivity Profiles Of Resting-State Networks In Marmosets And Humans, Yuki Hori, David J. Schaeffer, Atsushi Yoshida, Justine C. Cléry, Lauren K. Hayrynen, Joseph S. Gati, Ravi S. Menon, Stefan Everling Nov 2020

Cortico-Subcortical Functional Connectivity Profiles Of Resting-State Networks In Marmosets And Humans, Yuki Hori, David J. Schaeffer, Atsushi Yoshida, Justine C. Cléry, Lauren K. Hayrynen, Joseph S. Gati, Ravi S. Menon, Stefan Everling

Brain and Mind Institute Researchers' Publications

Copyright © 2020 the authors Understanding the similarity of cortico-subcortical networks topologies between humans and nonhuman primate species is critical to study the origin of network alternations underlying human neurologic and neuropsychiatric diseases. The New World common marmoset (Callithrix jacchus) has become popular as a nonhuman primate model for human brain function. Most marmoset connectomic research, however, has exclusively focused on cortical areas, with connectivity to subcortical networks less extensively explored. Here, we aimed to first isolate patterns of subcortical connectivity with cortical resting-state networks in awake marmosets using resting-state fMRI, then to compare these networks with those in humans …

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Neural Effects Of Oxytocin And Mimicry In Frontotemporal Dementia: A Randomized Crossover Study, Lindsay D. Oliver, Chloe Stewart, Kristy Coleman, James H. Kryklywy, Robert Bartha, Derek G.V. Mitchell, Elizabeth C. Finger Nov 2020

Neural Effects Of Oxytocin And Mimicry In Frontotemporal Dementia: A Randomized Crossover Study, Lindsay D. Oliver, Chloe Stewart, Kristy Coleman, James H. Kryklywy, Robert Bartha, Derek G.V. Mitchell, Elizabeth C. Finger

Medical Biophysics Publications

OBJECTIVE: To determine whether intranasal oxytocin, alone or in combination with instructed mimicry of facial expressions, would augment neural activity in patients with frontotemporal dementia (FTD) in brain regions associated with empathy, emotion processing, and the simulation network, as indexed by blood oxygen-level dependent (BOLD) signal during fMRI. METHODS: In a placebo-controlled, randomized crossover design, 28 patients with FTD received 72 IU intranasal oxytocin or placebo and then completed an fMRI facial expression mimicry task. RESULTS: Oxytocin alone and in combination with instructed mimicry increased activity in regions of the simulation network and in limbic regions associated with emotional expression …

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A Model Of Listening Engagement (Mole), Björn Herrmann, Ingrid S. Johnsrude Nov 2020

A Model Of Listening Engagement (Mole), Björn Herrmann, Ingrid S. Johnsrude

Brain and Mind Institute Researchers' Publications

Hearing impairment in older adulthood puts people at risk of communication difficulties, disengagement from listening, and social withdrawal. Here, we develop a model of listening engagement (MoLE) that provides a conceptual foundation to understand when people engage in listening and why some people disengage. We use the term “listening engagement” to describe the recruitment of executive and other cognitive resources in the service of a valued communication goal. Listening engagement, listening motivation, and listening experiences are closely interconnected: motivation and other factors determine the degree to which resources are recruited during listening, which in turn influences subjective listening experiences such …

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The Neural Basis Of Metacognitive Monitoring During Arithmetic In The Developing Brain, Elien Bellon, Wim Fias, Daniel Ansari, Bert De Smedt Nov 2020

The Neural Basis Of Metacognitive Monitoring During Arithmetic In The Developing Brain, Elien Bellon, Wim Fias, Daniel Ansari, Bert De Smedt

Brain and Mind Institute Researchers' Publications

In contrast to a substantial body of research on the neural basis of cognitive performance in several academic domains, less is known about how the brain generates metacognitive (MC) awareness of such performance. The existing work on the neurobiological underpinnings of metacognition has almost exclusively been done in adults and has largely focused on lower level cognitive processing domains, such as perceptual decision-making. Extending this body of evidence, we investigated MC monitoring by asking children to solve arithmetic problems, an educationally relevant higher-order process, while providing concurrent MC reports during fMRI acquisition. Results are reported on 50 primary school children …

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Higher Csf Strem2 Attenuates Apoe4-Related Risk For Cognitive Decline And Neurodegeneration, Nicolai Franzmeier, M. Suárez-Calvet, Lukas Frontzkowski, Annah Moore, Timothy J. Hohman, Estrella Morenas-Rodriguez, Brigitte Nuscher, Leslie Shaw, John Q. Trojanowski, Martin Dichgans, Gernot Kleinberger, Christian Haass, Michael Ewers, Michael Weiner, Paul Aisen, Gerald Novak, Robert C. Green, Tom Montine, Ronald Petersen, Anthony Gamst, Ronald G. Thomas, Michael Donohue, Sarah Walter, Devon Gessert, Tamie Sather, Laurel Beckett, Danielle Harvey, John Kornak, Clifford R. Jack, Anders Dale, Matthew Bernstein, Joel Felmlee Oct 2020

Higher Csf Strem2 Attenuates Apoe4-Related Risk For Cognitive Decline And Neurodegeneration, Nicolai Franzmeier, M. Suárez-Calvet, Lukas Frontzkowski, Annah Moore, Timothy J. Hohman, Estrella Morenas-Rodriguez, Brigitte Nuscher, Leslie Shaw, John Q. Trojanowski, Martin Dichgans, Gernot Kleinberger, Christian Haass, Michael Ewers, Michael Weiner, Paul Aisen, Gerald Novak, Robert C. Green, Tom Montine, Ronald Petersen, Anthony Gamst, Ronald G. Thomas, Michael Donohue, Sarah Walter, Devon Gessert, Tamie Sather, Laurel Beckett, Danielle Harvey, John Kornak, Clifford R. Jack, Anders Dale, Matthew Bernstein, Joel Felmlee

Medical Biophysics Publications

Background: The Apolipoprotein E ϵ4 allele (i.e. ApoE4) is the strongest genetic risk factor for sporadic Alzheimer's disease (AD). TREM2 (i.e. Triggering receptor expressed on myeloid cells 2) is a microglial transmembrane protein brain that plays a central role in microglia activation in response to AD brain pathologies. Whether higher TREM2-related microglia activity modulates the risk to develop clinical AD is an open question. Thus, the aim of the current study was to assess whether higher sTREM2 attenuates the effects of ApoE4-effects on future cognitive decline and neurodegeneration. Methods: We included 708 subjects ranging from cognitively normal (CN, n = …

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A Novel Salvage Option For Local Failure In Prostate Cancer, Reirradiation Using External Beam Or Stereotactic Radiation Therapy: Systematic Review And Meta-Analysis, Mark T. Corkum, Lucas C. Mendez, Joseph Chin, David D'Souza, R. Gabriel Boldt, Glenn S. Bauman Sep 2020

A Novel Salvage Option For Local Failure In Prostate Cancer, Reirradiation Using External Beam Or Stereotactic Radiation Therapy: Systematic Review And Meta-Analysis, Mark T. Corkum, Lucas C. Mendez, Joseph Chin, David D'Souza, R. Gabriel Boldt, Glenn S. Bauman

Medical Biophysics Publications

Purpose: Reirradiation (re-RT) using external beam radiation therapy (EBRT) is a novel salvage strategy for local failure in prostate cancer. We performed a systematic review describing oncologic and toxicity outcomes for salvage EBRT/stereotactic radiation therapy (SBRT) re-RT. Methods and Materials: A International Prospective Register of Systematic Reviews registered (#141466) systematic review, meta-analysis, and meta-regression was conducted using preferred reporting items for systematic reviews and meta-analyses guidelines. PubMed and EMBASE were searched from inception through September 2019. Outcome measures included local control (LC), biochemical relapse free survival (BRFS), and ≥grade 3 genitourinary (GU)/gastrointestinal (GI) toxicity. EBRT and SBRT data were collected …

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Syllables In Sync Form A Link: Neural Phase-Locking Reflects Word Knowledge During Language Learning, Laura Batterink Sep 2020

Syllables In Sync Form A Link: Neural Phase-Locking Reflects Word Knowledge During Language Learning, Laura Batterink

Brain and Mind Institute Researchers' Publications

Language is composed of small building blocks, which combine to form larger meaningful structures. To understand language, we must process, track, and concatenate these building blocks into larger linguistic units as speech unfolds over time. An influential idea is that phase-locking of neural oscillations across different levels of linguistic structure provides a mechanism for this process. Building on this framework, the goal of the current study was to determine whether neural phase-locking occurs more robustly to novel linguistic items that are successfully learned and encoded into memory, compared to items that are not learned. Participants listened to a continuous speech …

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Pain In The Newborn Brain: A Neural Signature, Emma G. Duerden, Steven P. Miller Sep 2020

Pain In The Newborn Brain: A Neural Signature, Emma G. Duerden, Steven P. Miller

Brain and Mind Institute Researchers' Publications

No abstract provided.

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An Auditory-Perceptual And Pupillometric Study Of Vocal Strain And Listening Effort In Adductor Spasmodic Dysphonia, Mojgan Farahani, Vijay Parsa, Björn Herrmann, Mason Kadem, Ingrid Johnsrude, Philip C. Doyle Sep 2020

An Auditory-Perceptual And Pupillometric Study Of Vocal Strain And Listening Effort In Adductor Spasmodic Dysphonia, Mojgan Farahani, Vijay Parsa, Björn Herrmann, Mason Kadem, Ingrid Johnsrude, Philip C. Doyle

Brain and Mind Institute Researchers' Publications

© 2020 by the authors. This study evaluated ratings of vocal strain and perceived listening effort by normal hearing participants while listening to speech samples produced by talkers with adductor spasmodic dysphonia (AdSD). In addition, objective listening effort was measured through concurrent pupillometry to determine whether listening to disordered voices changed arousal as a result of emotional state or cognitive load. Recordings of the second sentence of the "Rainbow Passage" produced by talkers with varying degrees of AdSD served as speech stimuli. Twenty naïve young adult listeners perceptually evaluated these stimuli on the dimensions of vocal strain and listening effort …

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Decoding Motor Imagery And Action Planning In The Early Visual Cortex: Overlapping But Distinct Neural Mechanisms, Simona Monaco, Giulia Malfatti, Jody C. Culham, Luigi Cattaneo, Luca Turella Sep 2020

Decoding Motor Imagery And Action Planning In The Early Visual Cortex: Overlapping But Distinct Neural Mechanisms, Simona Monaco, Giulia Malfatti, Jody C. Culham, Luigi Cattaneo, Luca Turella

Brain and Mind Institute Researchers' Publications

Recent evidence points to a role of the primary visual cortex that goes beyond visual processing into high-level cognitive and motor-related functions, including action planning, even in absence of feedforward visual information. It has been proposed that, at the neural level, motor imagery is a simulation based on motor representations, and neuroimaging studies have shown overlapping and shared activity patterns for motor imagery and action execution in frontal and parietal cortices. Yet, the role of the early visual cortex in motor imagery remains unclear. Here we used multivoxel pattern analyses on functional magnetic resonance imaging (fMRI) data to examine whether …

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