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The Left Hand Doesn't Know What The Right Hand Is Doing—Or Does It?, Jody C. Culham

Brain and Mind Institute Researchers' Publications

In this issue of Cell Reports, Ossmy and Mukamel (2016) show that virtual reality enhances learning of new motor sequences through practice with one hand and synchronous feedback of the other hand moving. The approach holds promise for motor rehabilitation.

Dysfunctional Insular Connectivity During Reward Prediction In Patients With First-Episode Psychosis, André Schmidt, Lena Palaniyappan, Renata Smieskova, Andor Simon, Anita Riecher-Rössler, Undine E. Lang, Paolo Fusar-Poli, Philip Mcguire, Stefan J. Borgwardt

Brain and Mind Institute Researchers' Publications

Background: Increasing evidence indicates that psychosis is associated with abnormal reward processing. Imaging studies in patients with first-episode psychosis (FEP) have revealed reduced activity in diverse brain regions, including the ventral striatum, insula and anterior cingulate cortex (ACC), during reward prediction. However, whether these reductions in local brain activity are due to altered connectivity has rarely been explored. Methods: We applied dynamic causal modelling and Bayesian model selection to fMRI data during the Salience Attribution Task to investigate whether patients with FEP showed abnormal modulation of connectivity between the ventral striatum, insula and ACC induced by rewarding cues and whether …

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 …

Globally Efficient Brain Organization And Treatment Response In Psychosis: A Connectomic Study Of Gyrification, Lena Palaniyappan, Tiago Reis Marques, Heather Taylor, Valeria Mondelli, A. A.T.Simone Reinders, Stefania Bonaccorso, Annalisa Giordano, Marta Diforti, Andrew Simmons, Anthony S. David, Carmine M. Pariante, Robin M. Murray, Paola Dazzan

Brain and Mind Institute Researchers' Publications

Background: Converging evidence suggests that patients with first-episode psychosis who show a poor treatment response may have a higher degree of neurodevelopmental abnormalities than good Responders. Characterizing the disturbances in the relationship among brain regions (covariance) can provide more information on neurodevelopmental integrity than searching for localized changes in the brain. Graph-based connectomic approach can measure structural covariance thus providing information on the maturational processes. We quantified the structural covariance of cortical folding using graph theory in first-episode psychosis, to investigate if this systems-level approach would improve our understanding of the biological determinants of outcome in psychosis. Methods: Magnetic Resonance …

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 …

Pramipexole Increases Go Timeouts But Not No-Go Errors In Healthy Volunteers, Xue Qing Yang, Daniel Glizer, Andrew Vo, Ken N. Seergobin, Penny A. Macdonald

Brain and Mind Institute Researchers' Publications

Parkinson’s disease (PD) is characterized by motor symptoms, such as resting tremor, bradykinesia and rigidity, but also features non-motor complications. PD patients taking dopaminergic therapy, such as levodopa but especially dopamine agonists (DAs), evidence an increase in impulse control disorders (ICDs), suggesting a link between dopaminergic therapy and impulsive pursuit of pleasurable activities. However, impulsivity is a multifaceted construct. Motor impulsivity refers to the inability to overcome automatic responses or cancel pre-potent responses. Previous research has suggested that PD patients, on dopaminergic medications, have decreased motor impulsivity. Whether effects on impulsivity are main effects of dopaminergic therapies or are specific …

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 …

Quantifying And Comparing The Pattern Of Thalamic And Cortical Projections To The Posterior Auditory Field In Hearing And Deaf Cats., Blake E Butler, Nicole Chabot, Stephen G Lomber

Brain and Mind Institute Researchers' Publications

Following sensory loss, compensatory crossmodal reorganization occurs such that the remaining modalities are functionally enhanced. For example, behavioral evidence suggests that peripheral visual localization is better in deaf than in normal hearing animals, and that this enhancement is mediated by recruitment of the posterior auditory field (PAF), an area that is typically involved in localization of sounds in normal hearing animals. To characterize the anatomical changes that underlie this phenomenon, we identified the thalamic and cortical projections to the PAF in hearing cats and those with early- and late-onset deafness. The retrograde tracer biotinylated dextran amine was deposited in the …

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 …

Using Facial Electromyography To Detect Preserved Emotional Processing In Disorders Of Consciousness: A Proof-Of-Principle Study, Chris M. Fiacconi, Adrian M. Owen

Brain and Mind Institute Researchers' Publications

Objective To examine whether emotional functioning can be observed in patients who are behaviourally non-responsive using peripheral markers of emotional functioning. Method We tested two patients, both diagnosed as being in a vegetative state (VS) following hypoxia secondary to cardiac arrest. Thirty-seven healthy participants with no history of neurological illness served as a control group. The activity of two facial muscles (zygomaticus major, corrugator supercilii) was measured using facial electromyography (EMG) to probe for patterned responses that differentiate between auditorily presented joke and non-joke stimuli in VS patients. Results One of the two VS patients we tested demonstrated greater zygomatic …

Probing The Nature Of Deficits In The ‘Approximate Number System’ In Children With Persistent Developmental Dyscalculia, S Bugden, Daniel Ansari

Brain and Mind Institute Researchers' Publications

In the present study we examined whether children with Developmental Dyscalculia (DD) exhibit a deficit in the so-called 'Approximate Number System' (ANS). To do so, we examined a group of elementary school children who demonstrated persistent low math achievement over 4 years and compared them to typically developing (TD), aged-matched controls. The integrity of the ANS was measured using the Panamath (www.panamath.org) non-symbolic numerical discrimination test. Children with DD demonstrated imprecise ANS acuity indexed by larger Weber fraction (w) compared to TD controls. Given recent findings showing that non-symbolic numerical discrimination is affected by visual parameters, we went further and …

Learning To Be Inflexible: Enhanced Attentional Biases In Parkinson's Disease, Sean James Fallon, Adam Hampshire, Roger A. Barker, Adrian M. Owen

Brain and Mind Institute Researchers' Publications

Impaired attentional flexibility is considered to be one of the core cognitive deficits in Parkinson's disease (PD). However, the mechanisms that underlie this impairment are contested. Progress in resolving this dispute has also been hindered by the fact that cognitive deficits in PD are heterogeneous; therefore, it is unclear whether attentional impairments are only present in a subgroup of patients. Here, we demonstrate that what differentiates PD patients from age-matched controls is an inability to shift attention away from previously relevant information (perseveration) and an inability to shift attention towards previously irrelevant information (learned irrelevance). In contrast, there was no …

Somatosensory Attention Identifies Both Overt And Covert Awareness In Disorders Of Consciousness, Raechelle M. Gibson, Srivas Chennu, Davinia Fernández-Espejo, Lorina Naci, Adrian M. Owen, Damian Cruse

Brain and Mind Institute Researchers' Publications

Objective: Some patients diagnosed with disorders of consciousness retain sensory and cognitive abilities beyond those apparent from their overt behavior. Characterizing these covert abilities is crucial for diagnosis, prognosis, and medical ethics. This multimodal study investigates the relationship between electroencephalographic evidence for perceptual/cognitive preservation and both overt and covert markers of awareness. Methods: Fourteen patients with severe brain injuries were evaluated with an electroencephalographic vibrotactile attention task designed to identify a hierarchy of residual somatosensory and cognitive abilities: (1) somatosensory steady-state evoked responses, (2) bottom-up attention orienting (P3a event-related potential), and (3) top-down attention (P3b event-related potential). Each patient was …

A Quantitative Comparison Of The Hemispheric, Areal, And Laminar Origins Of Sensory And Motor Cortical Projections To The Superior Colliculus Of The Cat., Blake E Butler, Nicole Chabot, Stephen G Lomber

Brain and Mind Institute Researchers' Publications

The superior colliculus (SC) is a midbrain structure central to orienting behaviors. The organization of descending projections from sensory cortices to the SC has garnered much attention; however, rarely have projections from multiple modalities been quantified and contrasted, allowing for meaningful conclusions within a single species. Here, we examine corticotectal projections from visual, auditory, somatosensory, motor, and limbic cortices via retrograde pathway tracers injected throughout the superficial and deep layers of the cat SC. As anticipated, the majority of cortical inputs to the SC originate in the visual cortex. In fact, each field implicated in visual orienting behavior makes a …

Interplay Of Brain Structure And Function In Neonatal Congenital Heart Disease, Ala Birca, Vasily A. Vakorin, Prashob Porayette, Sujana Madathil, Vann Chau, Mike Seed, Sam M. Doesburg, Susan Blaser, Dragos A. Nita, Rohit Sharma, Emma G. Duerden, Edward J. Hickey, Steven P. Miller, Cecil D. Hahn

Brain and Mind Institute Researchers' Publications

Objective: To evaluate whether structural and microstructural brain abnormalities in neonates with congenital heart disease (CHD) correlate with neuronal network dysfunction measured by analysis of EEG connectivity. Methods: We studied a prospective cohort of 20 neonates with CHD who underwent continuous EEG monitoring before surgery to assess functional brain maturation and network connectivity, structural magnetic resonance imaging (MRI) to determine the presence of brain injury and structural brain development, and diffusion tensor MRI to assess brain microstructural development. Results: Neonates with MRI brain injury and delayed structural and microstructural brain development demonstrated significantly stronger high-frequency (beta and gamma frequency band) …

Pramipexole Impairs Stimulus-Response Learning In Healthy Young Adults, Haley Gallant, Andrew Vo, Ken N. Seergobin, Penny A. Macdonald

Brain and Mind Institute Researchers' Publications

Dopaminergic therapy has paradoxical effects on cognition in Parkinson's disease (PD) patients, with some functions worsened and others improved. The dopamine overdose hypothesis is proposed as an explanation for these opposing effects of medication taking into account the varying levels of dopamine within different brain regions in PD. The detrimental effects of medication on cognition have been attributed to exogenous dopamine overdose in brain regions with spared dopamine levels in PD. It has been demonstrated that learning is most commonly worsened by dopaminergic medication. The current study aimed to investigate whether the medication-related learning impairment exhibited in PD patients is …

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 …

Why Numerical Symbols Count In The Development Of Mathematical Skills: Evidence From Brain And Behaviour, Rebecca Merkley, Daniel Ansari

Brain and Mind Institute Researchers' Publications

Numerical skills measured prior to school entry are predictive of mathematics achievement longitudinally. It is therefore important that young children start school with strong mathematical foundations. Here we review evidence from behavior and neuroimaging that highlights numerical symbol knowledge as a key mediator between informal and formal mathematical competencies. We argue that future research should aim to elucidate cognitive and neuronal mechanisms underpinning the acquisition of symbolic knowledge. Furthermore, multiple aspects of numerical symbol knowledge, such as identification, cardinality, and ordinality, should be emphasized in preschool childcare environments

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

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 …

A Longitudinal Investigation Of Predictors Of The Association Between Age 3 And Age 6 Behavioural Inhibition., Victoria C Johnson, Thomas M Olino, Daniel N Klein, Margaret W Dyson, Sara J Bufferd, C Emily Durbin, Lea R Dougherty, Elizabeth P Hayden

Brain and Mind Institute Researchers' Publications

Children who exhibit elevated levels of the temperament trait behavioural inhibition (BI) across time may be at greatest risk for anxiety. However, little research has investigated the influence of other temperamental traits, particularly positive emotionality (PE), on the continuity of BI in childhood, nor whether parental overprotection influences associations between early and later child BI. To explore whether PE and overprotection shape associations between early and later BI, this longitudinal study of three-year-olds (

Disentangling Representations Of Object And Grasp Properties In The Human Brain, Sara Fabbri, Kevin M. Stubbs, Rhodri Cusack, Jody C. Culham

Brain and Mind Institute Researchers' Publications

No abstract provided.

Health System Support And Health System Strengthening: Two Key Facilitators To The Implementation Of Ambulatory Tuberculosis Treatment In Uzbekistan, Stefan Köhler

Brain and Mind Institute Researchers' Publications

Uzbekistan inherited a hospital-based health system from the Soviet Union. We explore the health system-related challenges faced during the scale-up of ambulatory (outpatient) treatment for drug-susceptible and drug-resistant tuberculosis (TB) in Karakalpakstan in Uzbekistan. Semi-structured interviews were conducted with key informants of the TB services, the ministries of health and finance, and their TB control partners. Structural challenges and resource needs were both discussed as obstacles to the expansion of ambulatory TB treatment. Respondents stated need for revising the financing mechanisms of the TB services to incentivize referral to ambulatory TB treatment. An increased workload and need for transportation 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

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 …

Extracting Object Identity: Ventral Or Dorsal Visual Stream?, Vassilis Pelekanos, Marieke Mur, Katherine R. Storrs

Brain and Mind Institute Researchers' Publications

No abstract provided.

Cross-Modal Plasticity In Higher-Order Auditory Cortex Of Congenitally Deaf Cats Does Not Limit Auditory Responsiveness To Cochlear Implants, Rüdiger Land, Peter Baumhoff, Jochen Tillein, Stephen G. Lomber, Peter Hubka, Andrej Kral

Brain and Mind Institute Researchers' Publications

Congenital sensory deprivation can lead to reorganization of the deprived cortical regions by another sensory system. Such cross-modal reorganization may either compete with or complement the “original” inputs to the deprived area after sensory restoration and can thus be either adverse or beneficial for sensory restoration. In congenital deafness, a previous inactivation study documented that supranormal visual behavior was mediated by higher-order auditory fields in congenitally deaf cats (CDCs). However, both the auditory responsiveness of “deaf” higherorder fields and interactions between the reorganized and the original sensory input remain unknown. Here, we studied a higher-order auditory field responsible for the …

Insights Into Quasar Uv Spectra Using Unsupervised Clustering Analysis, A Tammour, S.C. Gallagher, M Daley, G.T. Richards

Brain and Mind Institute Researchers' Publications

Machine learning techniques can provide powerful tools to detect patterns in multidimensional parameter space. We use K-means - a simple yet powerful unsupervised clustering algorithm which picks out structure in unlabelled data - to study a sample of quasar UV spectra from the Quasar Catalog of the 10th Data Release of the Sloan Digital Sky Survey (SDSS-DR10) of Paris et al. Detecting patterns in large data sets helps us gain insights into the physical conditions and processes giving rise to the observed properties of quasars. We use K-means to find clusters in the parameter space of the equivalent width (EW), …

Cannabidiol Counteracts Amphetamine-Induced Neuronal And Behavioral Sensitization Of The Mesolimbic Dopamine Pathway Through A Novel Mtor/P70s6 Kinase Signaling Pathway, Justine Renard, Michael Loureiro, Laura G. Rosen, Jordan Zunder, Cleusa De Oliveira, Susanne Schmid, Walter J. Rushlow, Steven R. Laviolette

Brain and Mind Institute Researchers' Publications

Schizophrenia-related psychosis is associated with disturbances in mesolimbic dopamine (DA) transmission, characterized by hyperdopaminergic activity in the mesolimbic pathway. Currently, the only clinically effective treatment for schizophrenia involves the use of antipsychotic medications that blockDAreceptor transmission. However, these medications produce serious side effects leading to poor compliance and treatment outcomes. Emerging evidence points to the involvement of a specific phytochemical component of marijuana called cannabidiol (CBD), which possesses promising therapeutic properties for the treatment of schizophrenia-related psychoses. However, the neuronal and molecular mechanisms through which CBD may exert these effects are entirely unknown. We used amphetamine (AMPH)-induced sensitization and sensorimotor …

The Neural Roots Of Mathematical Expertise, Daniel Ansari

Brain and Mind Institute Researchers' Publications

No abstract provided.

Peripheral Causes Of Cognitive Motor Dissociation In Patients With Vegetative Or Minimally Conscious State: Reply, Davinia Fernández-Espejo, Adrian M. Owen

Brain and Mind Institute Researchers' Publications

No abstract provided.