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Full-Text Articles in Neurosciences

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 …


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 …


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 Oct 2019

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 Oct 2019

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, …


A Consensus Guide To Capturing The Ability To Inhibit Actions And Impulsive Behaviors In The Stop-Signal Task., Frederick Verbruggen, Adam R Aron, Guido Ph Band, Christian Beste, Patrick G Bissett, Adam T Brockett, Joshua W Brown, Samuel R Chamberlain, Christopher D Chambers, Hans Colonius, Lorenza S Colzato, Brian D Corneil, James P Coxon, Annie Dupuis, Dawn M Eagle, Hugh Garavan, Ian Greenhouse, Andrew Heathcote, René J Huster, Sara Jahfari, J Leon Kenemans, Inge Leunissen, Chiang-Shan R Li, Gordon D Logan, Dora Matzke, Sharon Morein-Zamir, Aditya Murthy, Martin Paré, Russell A Poldrack, K Richard Ridderinkhof, Trevor W Robbins, Matthew Roesch, Katya Rubia, Russell J Schachar, Jeffrey D Schall, Ann-Kathrin Stock, Nicole C Swann, Katharine N Thakkar, Maurits W Van Der Molen, Luc Vermeylen, Matthijs Vink, Jan R Wessel, Robert Whelan, Bram B Zandbelt, C Nico Boehler Apr 2019

A Consensus Guide To Capturing The Ability To Inhibit Actions And Impulsive Behaviors In The Stop-Signal Task., Frederick Verbruggen, Adam R Aron, Guido Ph Band, Christian Beste, Patrick G Bissett, Adam T Brockett, Joshua W Brown, Samuel R Chamberlain, Christopher D Chambers, Hans Colonius, Lorenza S Colzato, Brian D Corneil, James P Coxon, Annie Dupuis, Dawn M Eagle, Hugh Garavan, Ian Greenhouse, Andrew Heathcote, René J Huster, Sara Jahfari, J Leon Kenemans, Inge Leunissen, Chiang-Shan R Li, Gordon D Logan, Dora Matzke, Sharon Morein-Zamir, Aditya Murthy, Martin Paré, Russell A Poldrack, K Richard Ridderinkhof, Trevor W Robbins, Matthew Roesch, Katya Rubia, Russell J Schachar, Jeffrey D Schall, Ann-Kathrin Stock, Nicole C Swann, Katharine N Thakkar, Maurits W Van Der Molen, Luc Vermeylen, Matthijs Vink, Jan R Wessel, Robert Whelan, Bram B Zandbelt, C Nico Boehler

Brain and Mind Institute Researchers' Publications

Response inhibition is essential for navigating everyday life. Its derailment is considered integral to numerous neurological and psychiatric disorders, and more generally, to a wide range of behavioral and health problems. Response-inhibition efficiency furthermore correlates with treatment outcome in some of these conditions. The stop-signal task is an essential tool to determine how quickly response inhibition is implemented. Despite its apparent simplicity, there are many features (ranging from task design to data analysis) that vary across studies in ways that can easily compromise the validity of the obtained results. Our goal is to facilitate a more accurate use of the …


Abstract Concepts And Pictures Of Real-World Situations Activate One Another., Ken Mcrae, Daniel Nedjadrasul, Raymond Pau, Bethany Pui-Hei Lo, Lisa King Jul 2018

Abstract Concepts And Pictures Of Real-World Situations Activate One Another., Ken Mcrae, Daniel Nedjadrasul, Raymond Pau, Bethany Pui-Hei Lo, Lisa King

Brain and Mind Institute Researchers' Publications

concepts typically are defined in terms of lacking physical or perceptual referents. We argue instead that they are not devoid of perceptual information because knowledge of real-world situations is an important component of learning and using many abstract concepts. Although the relationship between perceptual information and abstract concepts is less straightforward than for concrete concepts, situation-based perceptual knowledge is part of many abstract concepts. In Experiment 1, participants made lexical decisions to abstract words that were preceded by related and unrelated pictures of situations. For example, share was preceded by a picture of two girls sharing a cob of corn. …


Neural Mechanisms Of The Rejection-Aggression Link, David S. Chester, Donald R. Lynam, Richard Milich, C. Nathan Dewall May 2018

Neural Mechanisms Of The Rejection-Aggression Link, David S. Chester, Donald R. Lynam, Richard Milich, C. Nathan Dewall

Psychology Faculty Publications

Social rejection is a painful event that often increases aggression. However, the neural mechanisms of this rejection–aggression link remain unclear. A potential clue may be that rejected people often recruit the ventrolateral prefrontal cortex’s (VLPFC) self-regulatory processes to manage the pain of rejection. Using functional MRI, we replicated previous links between rejection and activity in the brain’s mentalizing network, social pain network and VLPFC. VLPFC recruitment during rejection was associated with greater activity in the brain’s reward network (i.e. the ventral striatum) when individuals were given an opportunity to retaliate. This retaliation-related striatal response was associated with greater levels of …


Seeing The Forest And The Trees: Default Local Processing In Individuals With High Autistic Traits Does Not Come At The Expense Of Global Attention., Ryan A Stevenson, Sol Z Sun, Naomi Hazlett, Jonathan S Cant, Morgan D Barense, Susanne Ferber Apr 2018

Seeing The Forest And The Trees: Default Local Processing In Individuals With High Autistic Traits Does Not Come At The Expense Of Global Attention., Ryan A Stevenson, Sol Z Sun, Naomi Hazlett, Jonathan S Cant, Morgan D Barense, Susanne Ferber

Brain and Mind Institute Researchers' Publications

Atypical sensory perception is one of the most ubiquitous symptoms of autism, including a tendency towards a local-processing bias. We investigated whether local-processing biases were associated with global-processing impairments on a global/local attentional-scope paradigm in conjunction with a composite-face task. Behavioural results were related to individuals' levels of autistic traits, specifically the Attention to Detail subscale of the Autism Quotient, and the Sensory Profile Questionnaire. Individuals showing high rates of Attention to Detail were more susceptible to global attentional-scope manipulations, suggesting that local-processing biases associated with Attention to Detail do not come at the cost of a global-processing deficit, but …


Nutrient Intake In The First Two Weeks Of Life And Brain Growth In Preterm Neonates., Juliane Schneider, Céline J Fischer Fumeaux, Emma G Duerden, Ting Guo, Justin Foong, Myriam Bickle Graz, Patric Hagmann, M Mallar Chakravarty, Petra S Hüppi, Lydie Beauport, Anita C Truttmann, Steven P Miller Mar 2018

Nutrient Intake In The First Two Weeks Of Life And Brain Growth In Preterm Neonates., Juliane Schneider, Céline J Fischer Fumeaux, Emma G Duerden, Ting Guo, Justin Foong, Myriam Bickle Graz, Patric Hagmann, M Mallar Chakravarty, Petra S Hüppi, Lydie Beauport, Anita C Truttmann, Steven P Miller

Brain and Mind Institute Researchers' Publications

BACKGROUND: Optimizing early nutritional intake in preterm neonates may promote brain health and neurodevelopment through enhanced brain maturation. Our objectives were (1) to determine the association of energy and macronutrient intake in the first 2 weeks of life with regional and total brain growth and white matter (WM) maturation, assessed by 3 serial MRI scans in preterm neonates; (2) to examine how critical illness modifies this association; and (3) to investigate the relationship with neurodevelopmental outcomes.

METHODS: Forty-nine preterm neonates (21 boys, median [interquartile range] gestational age: 27.6 [2.3] weeks) were scanned serially at the following median postmenstrual weeks: 29.4, …


Early Procedural Pain Is Associated With Regionally-Specific Alterations In Thalamic Development In Preterm Neonates., Emma G Duerden, Ruth E Grunau, Ting Guo, Justin Foong, Alexander Pearson, Stephanie Au-Young, Raphael Lavoie, M Mallar Chakravarty, Vann Chau, Anne Synnes, Steven P Miller Jan 2018

Early Procedural Pain Is Associated With Regionally-Specific Alterations In Thalamic Development In Preterm Neonates., Emma G Duerden, Ruth E Grunau, Ting Guo, Justin Foong, Alexander Pearson, Stephanie Au-Young, Raphael Lavoie, M Mallar Chakravarty, Vann Chau, Anne Synnes, Steven P Miller

Brain and Mind Institute Researchers' Publications

Very preterm human neonates are exposed to numerous invasive procedures as part of life-saving care. Evidence suggests that repetitive neonatal procedural pain precedes long-term alterations in brain development. However, to date the link between pain and brain development has limited temporal and anatomic specificity. We hypothesized that early exposure to painful stimuli during a period of rapid brain development, before pain modulatory systems reach maturity, will predict pronounced changes in thalamic development, and thereby cognitive and motor function. In a prospective cohort study, 155 very preterm neonates (82 males, 73 females) born 24-32 weeks' gestation underwent two MRIs at median …


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 Jan 2018

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), …


Higher And Lower Order Factor Analyses Of The Temperament In Middle Childhood Questionnaire., Yuliya Kotelnikova, Thomas M Olino, Daniel N Klein, Sarah V M Mackrell, Elizabeth P Hayden Dec 2017

Higher And Lower Order Factor Analyses Of The Temperament In Middle Childhood Questionnaire., Yuliya Kotelnikova, Thomas M Olino, Daniel N Klein, Sarah V M Mackrell, Elizabeth P Hayden

Brain and Mind Institute Researchers' Publications

The Temperament in Middle Childhood Questionnaire (TMCQ) is a widely used parent-report measure of temperament. However, neither its lower nor higher order structures has been tested via a bottom-up, empirically based approach. We conducted higher and lower order exploratory factor analyses (EFAs) of the TMCQ in a large ( N = 654) sample of 9-year-olds. Item-level EFAs identified 92 items as suitable (i.e., with loadings ≥.40) for constructing lower order factors, only half of which resembled a TMCQ scale posited by the measure's authors. Higher order EFAs of the lower order factors showed that a three-factor structure (Impulsivity/Negative Affectivity, Negative …


Vocabulary Learning Benefits From Rem After Slow-Wave Sleep., Laura J Batterink, Carmen E Westerberg, Ken A Paller Oct 2017

Vocabulary Learning Benefits From Rem After Slow-Wave Sleep., Laura J Batterink, Carmen E Westerberg, Ken A Paller

Brain and Mind Institute Researchers' Publications

Memory reactivation during slow-wave sleep (SWS) influences the consolidation of recently acquired knowledge. This reactivation occurs spontaneously during sleep but can also be triggered by presenting learning-related cues, a technique known as targeted memory reactivation (TMR). Here we examined whether TMR can improve vocabulary learning. Participants learned the meanings of 60 novel words. Auditory cues for half the words were subsequently presented during SWS in an afternoon nap. Memory performance for cued versus uncued words did not differ at the group level but was systematically influenced by REM sleep duration. Participants who obtained relatively greater amounts of REM showed a …


Rapid Statistical Learning Supporting Word Extraction From Continuous Speech., Laura J Batterink Jul 2017

Rapid Statistical Learning Supporting Word Extraction From Continuous Speech., Laura J Batterink

Brain and Mind Institute Researchers' Publications

The identification of words in continuous speech, known as speech segmentation, is a critical early step in language acquisition. This process is partially supported by statistical learning, the ability to extract patterns from the environment. Given that speech segmentation represents a potential bottleneck for language acquisition, patterns in speech may be extracted very rapidly, without extensive exposure. This hypothesis was examined by exposing participants to continuous speech streams composed of novel repeating nonsense words. Learning was measured on-line using a reaction time task. After merely one exposure to an embedded novel word, learners demonstrated significant learning effects, as revealed by …


Representation Of Multiple Body Parts In The Missing-Hand Territory Of Congenital One-Handers., Avital Hahamy, Scott N Macdonald, Fiona Van Den Heiligenberg, Paullina Kieliba, Uzay Emir, Rafael Malach, Heidi Johansen-Berg, Peter Brugger, Jody C Culham, Tamar R Makin May 2017

Representation Of Multiple Body Parts In The Missing-Hand Territory Of Congenital One-Handers., Avital Hahamy, Scott N Macdonald, Fiona Van Den Heiligenberg, Paullina Kieliba, Uzay Emir, Rafael Malach, Heidi Johansen-Berg, Peter Brugger, Jody C Culham, Tamar R Makin

Brain and Mind Institute Researchers' Publications

Individuals born without one hand (congenital one-handers) provide a unique model for understanding the relationship between focal reorganization in the sensorimotor cortex and everyday behavior. We previously reported that the missing hand's territory of one-handers becomes utilized by its cortical neighbor (residual arm representation), depending on residual arm usage in daily life to substitute for the missing hand's function [1, 2]. However, the repertoire of compensatory behaviors may involve utilization of other body parts that do not cortically neighbor the hand territory. Accordingly, the pattern of brain reorganization may be more extensive [3]. Here we studied unconstrained compensatory strategies under …


Sensory Processing In Autism Spectrum Disorders And Fragile X Syndrome-From The Clinic To Animal Models., D Sinclair, B Oranje, K A Razak, S J Siegel, S Schmid May 2017

Sensory Processing In Autism Spectrum Disorders And Fragile X Syndrome-From The Clinic To Animal Models., D Sinclair, B Oranje, K A Razak, S J Siegel, S Schmid

Brain and Mind Institute Researchers' Publications

Brains are constantly flooded with sensory information that needs to be filtered at the pre-attentional level and integrated into endogenous activity in order to allow for detection of salient information and an appropriate behavioral response. People with Autism Spectrum Disorder (ASD) or Fragile X Syndrome (FXS) are often over- or under-reactive to stimulation, leading to a wide range of behavioral symptoms. This altered sensitivity may be caused by disrupted sensory processing, signal integration and/or gating, and is often being neglected. Here, we review translational experimental approaches that are used to investigate sensory processing in humans with ASD and FXS, and …


Online Neural Monitoring Of Statistical Learning., Laura J Batterink, Ken A Paller May 2017

Online Neural Monitoring Of Statistical Learning., Laura J Batterink, Ken A Paller

Brain and Mind Institute Researchers' Publications

The extraction of patterns in the environment plays a critical role in many types of human learning, from motor skills to language acquisition. This process is known as statistical learning. Here we propose that statistical learning has two dissociable components: (1) perceptual binding of individual stimulus units into integrated composites and (2) storing those integrated representations for later use. Statistical learning is typically assessed using post-learning tasks, such that the two components are conflated. Our goal was to characterize the online perceptual component of statistical learning. Participants were exposed to a structured stream of repeating trisyllabic nonsense words and a …


Sleep-Based Memory Processing Facilitates Grammatical Generalization: Evidence From Targeted Memory Reactivation., Laura J Batterink, Ken A Paller Apr 2017

Sleep-Based Memory Processing Facilitates Grammatical Generalization: Evidence From Targeted Memory Reactivation., Laura J Batterink, Ken A Paller

Brain and Mind Institute Researchers' Publications

Generalization-the ability to abstract regularities from specific examples and apply them to novel instances-is an essential component of language acquisition. Generalization not only depends on exposure to input during wake, but may also improve offline during sleep. Here we examined whether targeted memory reactivation during sleep can influence grammatical generalization. Participants gradually acquired the grammatical rules of an artificial language through an interactive learning procedure. Then, phrases from the language (experimental group) or stimuli from an unrelated task (control group) were covertly presented during an afternoon nap. Compared to control participants, participants re-exposed to the language during sleep showed larger …


Adaptable Categorization Of Hands And Tools In Prosthesis Users., Fiona M Z Van Den Heiligenberg, Nick Yeung, Peter Brugger, Jody C Culham, Tamar R Makin Mar 2017

Adaptable Categorization Of Hands And Tools In Prosthesis Users., Fiona M Z Van Den Heiligenberg, Nick Yeung, Peter Brugger, Jody C Culham, Tamar R Makin

Brain and Mind Institute Researchers' Publications

No abstract provided.


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 Feb 2017

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 …


Skilled Adult Readers Activate The Meanings Of High-Frequency Words Using Phonology: Evidence From Eye Tracking., Debra Jared, Katrina O'Donnell Feb 2017

Skilled Adult Readers Activate The Meanings Of High-Frequency Words Using Phonology: Evidence From Eye Tracking., Debra Jared, Katrina O'Donnell

Brain and Mind Institute Researchers' Publications

We examined whether highly skilled adult readers activate the meanings of high-frequency words using phonology when reading sentences for meaning. A homophone-error paradigm was used. Sentences were written to fit 1 member of a homophone pair, and then 2 other versions were created in which the homophone was replaced by its mate or a spelling-control word. The error words were all high-frequency words, and the correct homophones were either higher-frequency words or low-frequency words-that is, the homophone errors were either the subordinate or dominant member of the pair. Participants read sentences as their eye movements were tracked. When the high-frequency …


The Serotonin Transporter Promoter Polymorphism Moderates The Continuity Of Behavioral Inhibition In Early Childhood., Victoria C Johnson, Katie R Kryski, Haroon I Sheikh, Heather J Smith, Shiva M Singh, Elizabeth P Hayden Nov 2016

The Serotonin Transporter Promoter Polymorphism Moderates The Continuity Of Behavioral Inhibition In Early Childhood., Victoria C Johnson, Katie R Kryski, Haroon I Sheikh, Heather J Smith, Shiva M Singh, Elizabeth P Hayden

Brain and Mind Institute Researchers' Publications

Persistently elevated behavioral inhibition (BI) in children is a marker of vulnerability to psychopathology. However, little research has considered the joint influences of caregiver and child factors that may moderate the continuity of BI in early childhood, particularly genetic variants that may serve as markers of biological plasticity, such as the serotonin transporter linked polymorphic region (5-HTTLPR). We explored this issue in 371 preschoolers and their caregivers, examining whether parent characteristics (i.e., overinvolvement or anxiety disorder) and child 5-HTTLPR influenced the continuity of BI between ages 3 and 5. Measures were observational ratings of child BI, observational and questionnaire measures …


Resting-State Network-Specific Breakdown Of Functional Connectivity During Ketamine Alteration Of Consciousness In Volunteers., Vincent Bonhomme, Audrey Vanhaudenhuyse, Athena Demertzi, Marie-Aurélie Bruno, Oceane Jaquet, Mohamed Ali Bahri, Alain Plenevaux, Melanie Boly, Pierre Boveroux, Andrea Soddu, Jean François Brichant, Pierre Maquet, Steven Laureys Nov 2016

Resting-State Network-Specific Breakdown Of Functional Connectivity During Ketamine Alteration Of Consciousness In Volunteers., Vincent Bonhomme, Audrey Vanhaudenhuyse, Athena Demertzi, Marie-Aurélie Bruno, Oceane Jaquet, Mohamed Ali Bahri, Alain Plenevaux, Melanie Boly, Pierre Boveroux, Andrea Soddu, Jean François Brichant, Pierre Maquet, Steven Laureys

Brain and Mind Institute Researchers' Publications

BACKGROUND: Consciousness-altering anesthetic agents disturb connectivity between brain regions composing the resting-state consciousness networks (RSNs). The default mode network (DMn), executive control network, salience network (SALn), auditory network, sensorimotor network (SMn), and visual network sustain mentation. Ketamine modifies consciousness differently from other agents, producing psychedelic dreaming and no apparent interaction with the environment. The authors used functional magnetic resonance imaging to explore ketamine-induced changes in RSNs connectivity.

METHODS: Fourteen healthy volunteers received stepwise intravenous infusions of ketamine up to loss of responsiveness. Because of agitation, data from six subjects were excluded from analysis. RSNs connectivity was compared between absence of …


Usage Of Swi (Susceptibility Weighted Imaging) Acquired At 7t For Qualitative Evaluation Of Temporal Lobe Epilepsy Patients With Histopathological And Clinical Correlation: An Initial Pilot Study., Benjamin Y M Kwan, Fateme Salehi, Pavlo Ohorodnyk, Donald H Lee, Jorge G Burneo, Seyed M Mirsattari, David Steven, Robert Hammond, Terry M Peters, Ali R Khan Oct 2016

Usage Of Swi (Susceptibility Weighted Imaging) Acquired At 7t For Qualitative Evaluation Of Temporal Lobe Epilepsy Patients With Histopathological And Clinical Correlation: An Initial Pilot Study., Benjamin Y M Kwan, Fateme Salehi, Pavlo Ohorodnyk, Donald H Lee, Jorge G Burneo, Seyed M Mirsattari, David Steven, Robert Hammond, Terry M Peters, Ali R Khan

Brain and Mind Institute Researchers' Publications

OBJECTIVES: Ultra high field MRI at 7T is able to provide much improved spatial and contrast resolution which may aid in the diagnosis of hippocampal abnormalities. This paper presents a preliminary experience on qualitative evaluation of 7T MRI in temporal lobe epilepsy patients with a focus on comparison to histopathology.

METHODS: 7T ultra high field MRI data, using T1-weighted, T2*-weighted and susceptibility-weighted images (SWI), were acquired for 13 patients with drug resistant temporal lobe epilepsy (TLE) during evaluation for potential epilepsy surgery. Qualitative evaluation of the imaging data for scan quality and presence of hippocampal and temporal lobe abnormalities were …


Neural Measures Reveal Implicit Learning During Language Processing., Laura J Batterink, Larry Y Cheng, Ken A Paller Oct 2016

Neural Measures Reveal Implicit Learning During Language Processing., Laura J Batterink, Larry Y Cheng, Ken A Paller

Brain and Mind Institute Researchers' Publications

Language input is highly variable; phonological, lexical, and syntactic features vary systematically across different speakers, geographic regions, and social contexts. Previous evidence shows that language users are sensitive to these contextual changes and that they can rapidly adapt to local regularities. For example, listeners quickly adjust to accented speech, facilitating comprehension. It has been proposed that this type of adaptation is a form of implicit learning. This study examined a similar type of adaptation, syntactic adaptation, to address two issues: (1) whether language comprehenders are sensitive to a subtle probabilistic contingency between an extraneous feature (font color) and syntactic structure …


A Trial-By-Trial Window Into Sensorimotor Transformations In The Human Motor Periphery., Chao Gu, Daniel K Wood, Paul L Gribble, Brian D Corneil Aug 2016

A Trial-By-Trial Window Into Sensorimotor Transformations In The Human Motor Periphery., Chao Gu, Daniel K Wood, Paul L Gribble, Brian D Corneil

Brain and Mind Institute Researchers' Publications

UNLABELLED: The appearance of a novel visual stimulus generates a rapid stimulus-locked response (SLR) in the motor periphery within 100 ms of stimulus onset. Here, we recorded SLRs from an upper limb muscle while humans reached toward (pro-reach) or away (anti-reach) from a visual stimulus. The SLR on anti-reaches encoded the location of the visual stimulus rather than the movement goal. Further, SLR magnitude was attenuated when subjects reached away from rather than toward the visual stimulus. Remarkably, SLR magnitudes also correlated with reaction times on both pro-reaches and anti-reaches, but did so in opposite ways: larger SLRs preceded shorter …


Effects Of Material Properties And Object Orientation On Precision Grip Kinematics., Vivian C Paulun, Karl R Gegenfurtner, Melvyn A Goodale, Roland W Fleming Aug 2016

Effects Of Material Properties And Object Orientation On Precision Grip Kinematics., Vivian C Paulun, Karl R Gegenfurtner, Melvyn A Goodale, Roland W Fleming

Brain and Mind Institute Researchers' Publications

Successfully picking up and handling objects requires taking into account their physical properties (e.g., material) and position relative to the body. Such features are often inferred by sight, but it remains unclear to what extent observers vary their actions depending on the perceived properties. To investigate this, we asked participants to grasp, lift and carry cylinders to a goal location with a precision grip. The cylinders were made of four different materials (Styrofoam, wood, brass and an additional brass cylinder covered with Vaseline) and were presented at six different orientations with respect to the participant (0°, 30°, 60°, 90°, 120°, …


Rapid Decrement In The Effects Of The Ponzo Display Dissociates Action And Perception., Robert L Whitwell, Gavin Buckingham, James T Enns, Philippe A Chouinard, Melvyn A Goodale Aug 2016

Rapid Decrement In The Effects Of The Ponzo Display Dissociates Action And Perception., Robert L Whitwell, Gavin Buckingham, James T Enns, Philippe A Chouinard, Melvyn A Goodale

Brain and Mind Institute Researchers' Publications

It has been demonstrated that pictorial illusions have a smaller influence on grasping than they do on perceptual judgments. Yet to date this work has not considered the reduced influence of an illusion as it is measured repeatedly. Here we studied this decrement in the context of a Ponzo illusion to further characterize the dissociation between vision for perception and for action. Participants first manually estimated the lengths of single targets in a Ponzo display with their thumb and index finger, then actually grasped these targets in another series of trials, and then manually estimated the target lengths again in …


Cerebral Functional Connectivity Periodically (De)Synchronizes With Anatomical Constraints., Raphaël Liégeois, Erik Ziegler, Christophe Phillips, Pierre Geurts, Francisco Gómez, Mohamed Ali Bahri, B T Thomas Yeo, Andrea Soddu, Audrey Vanhaudenhuyse, Steven Laureys, Rodolphe Sepulchre Jul 2016

Cerebral Functional Connectivity Periodically (De)Synchronizes With Anatomical Constraints., Raphaël Liégeois, Erik Ziegler, Christophe Phillips, Pierre Geurts, Francisco Gómez, Mohamed Ali Bahri, B T Thomas Yeo, Andrea Soddu, Audrey Vanhaudenhuyse, Steven Laureys, Rodolphe Sepulchre

Brain and Mind Institute Researchers' Publications

This paper studies the link between resting-state functional connectivity (FC), measured by the correlations of fMRI BOLD time courses, and structural connectivity (SC), estimated through fiber tractography. Instead of a static analysis based on the correlation between SC and FC averaged over the entire fMRI time series, we propose a dynamic analysis, based on the time evolution of the correlation between SC and a suitably windowed FC. Assessing the statistical significance of the time series against random phase permutations, our data show a pronounced peak of significance for time window widths around 20-30 TR (40-60 s). Using the appropriate window …


Functional Plasticity In Somatosensory Cortex Supports Motor Learning By Observing., Heather R Mcgregor, Joshua G A Cashaback, Paul L Gribble Apr 2016

Functional Plasticity In Somatosensory Cortex Supports Motor Learning By Observing., Heather R Mcgregor, Joshua G A Cashaback, Paul L Gribble

Brain and Mind Institute Researchers' Publications

An influential idea in neuroscience is that the sensory-motor system is activated when observing the actions of others [1, 2]. This idea has recently been extended to motor learning, in which observation results in sensory-motor plasticity and behavioral changes in both motor and somatosensory domains [3-9]. However, it is unclear how the brain maps visual information onto motor circuits for learning. Here we test the idea that the somatosensory system, and specifically primary somatosensory cortex (S1), plays a role in motor learning by observing. In experiment 1, we applied stimulation to the median nerve to occupy the somatosensory system with …