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Full-Text Articles in Medical Sciences

Equal-Magnitude Size-Weight Illusions Experienced Within And Between Object Categories., Gavin Buckingham, Melvyn A Goodale, Justin A White, David A Westwood Jan 2016

Equal-Magnitude Size-Weight Illusions Experienced Within And Between Object Categories., Gavin Buckingham, Melvyn A Goodale, Justin A White, David A Westwood

Brain and Mind Institute Researchers' Publications

In the size-weight illusion (SWI), small objects feel heavier than larger objects of the same mass. This effect is typically thought to be a consequence of the lifter's expectation that the large object will outweigh the small object, because objects of the same type typically get heavier as they get larger. Here, we show that this perceptual effect can occur across object category, where there are no strong expectations about the correspondence between size and mass. One group of participants lifted same-colored large and small cubes with the same mass as one another, while another group lifted differently-colored large and …


Ethnic Differences In Maternal Adipokines During Normal Pregnancy, Xinhua Chen, Theresa O Scholl Dec 2015

Ethnic Differences In Maternal Adipokines During Normal Pregnancy, Xinhua Chen, Theresa O Scholl

Rowan-Virtua School of Osteopathic Medicine Departmental Research

Two adipokines (adiponectin and resistin) have opposite relations with insulin resistance and inflammation. Our major focus was to determine whether there were detectable ethnic differences in maternal adipokines during pregnancy. We also explored the correlation of the adipokines with maternal glucose homeostasis, blood pressure and anthropometric parameters. Pregnant women (n = 1634) were from a large prospective cohort study in Camden NJ (African-American 36.8%; Hispanic 47.6%; Caucasian 15.6%). Serum adiponectin and resistin were measured at entry (week 16.8) and the 3rd trimester (week 30.7) using the Luminex xMapTechnology. Significant differences were observed among ethnic groups, controlling for confounding variables. African …


Functional Differences Between Statistical Learning With And Without Explicit Training., Laura J Batterink, Paul J Reber, Ken A Paller Nov 2015

Functional Differences Between Statistical Learning With And Without Explicit Training., Laura J Batterink, Paul J Reber, Ken A Paller

Brain and Mind Institute Researchers' Publications

Humans are capable of rapidly extracting regularities from environmental input, a process known as statistical learning. This type of learning typically occurs automatically, through passive exposure to environmental input. The presumed function of statistical learning is to optimize processing, allowing the brain to more accurately predict and prepare for incoming input. In this study, we ask whether the function of statistical learning may be enhanced through supplementary explicit training, in which underlying regularities are explicitly taught rather than simply abstracted through exposure. Learners were randomly assigned either to an explicit group or an implicit group. All learners were exposed to …


Transient Visual Responses Reset The Phase Of Low-Frequency Oscillations In The Skeletomotor Periphery., Daniel K Wood, Chao Gu, Brian D Corneil, Paul L Gribble, Melvyn A Goodale Aug 2015

Transient Visual Responses Reset The Phase Of Low-Frequency Oscillations In The Skeletomotor Periphery., Daniel K Wood, Chao Gu, Brian D Corneil, Paul L Gribble, Melvyn A Goodale

Brain and Mind Institute Researchers' Publications

We recorded muscle activity from an upper limb muscle while human subjects reached towards peripheral targets. We tested the hypothesis that the transient visual response sweeps not only through the central nervous system, but also through the peripheral nervous system. Like the transient visual response in the central nervous system, stimulus-locked muscle responses (< 100 ms) were sensitive to stimulus contrast, and were temporally and spatially dissociable from voluntary orienting activity. Also, the arrival of visual responses reduced the variability of muscle activity by resetting the phase of ongoing low-frequency oscillations. This latter finding critically extends the emerging evidence that the feedforward visual sweep reduces neural variability via phase resetting. We conclude that, when sensory information is relevant to a particular effector, detailed information about the sensorimotor transformation, even from the earliest stages, is found in the peripheral nervous system.


Hand Use Predicts The Structure Of Representations In Sensorimotor Cortex., Naveed Ejaz, Masashi Hamada, Jörn Diedrichsen Jul 2015

Hand Use Predicts The Structure Of Representations In Sensorimotor Cortex., Naveed Ejaz, Masashi Hamada, Jörn Diedrichsen

Brain and Mind Institute Researchers' Publications

Fine finger movements are controlled by the population activity of neurons in the hand area of primary motor cortex. Experiments using microstimulation and single-neuron electrophysiology suggest that this area represents coordinated multi-joint, rather than single-finger movements. However, the principle by which these representations are organized remains unclear. We analyzed activity patterns during individuated finger movements using functional magnetic resonance imaging (fMRI). Although the spatial layout of finger-specific activity patterns was variable across participants, the relative similarity between any pair of activity patterns was well preserved. This invariant organization was better explained by the correlation structure of everyday hand movements than …


Changes In Visual And Sensory-Motor Resting-State Functional Connectivity Support Motor Learning By Observing., Heather R Mcgregor, Paul L Gribble Jul 2015

Changes In Visual And Sensory-Motor Resting-State Functional Connectivity Support Motor Learning By Observing., Heather R Mcgregor, Paul L Gribble

Brain and Mind Institute Researchers' Publications

Motor learning occurs not only through direct first-hand experience but also through observation (Mattar AA, Gribble PL. Neuron 46: 153-160, 2005). When observing the actions of others, we activate many of the same brain regions involved in performing those actions ourselves (Malfait N, Valyear KF, Culham JC, Anton JL, Brown LE, Gribble PL. J Cogn Neurosci 22: 1493-1503, 2010). Links between neural systems for vision and action have been reported in neurophysiological (Strafella AP, Paus T. Neuroreport 11: 2289-2292, 2000; Watkins KE, Strafella AP, Paus T. Neuropsychologia 41: 989-994, 2003), brain imaging (Buccino G, Binkofski F, Fink GR, Fadiga L, …


Fusion Analysis Of Functional Mri Data For Classification Of Individuals Based On Patterns Of Activation., Mahdi Ramezani, Purang Abolmaesumi, Kris Marble, Heather Trang, Ingrid Johnsrude Jun 2015

Fusion Analysis Of Functional Mri Data For Classification Of Individuals Based On Patterns Of Activation., Mahdi Ramezani, Purang Abolmaesumi, Kris Marble, Heather Trang, Ingrid Johnsrude

Brain and Mind Institute Researchers' Publications

Classification of individuals based on patterns of brain activity observed in functional MRI contrasts may be helpful for diagnosis of neurological disorders. Prior work for classification based on these patterns have primarily focused on using a single contrast, which does not take advantage of complementary information that may be available in multiple contrasts. Where multiple contrasts are used, the objective has been only to identify the joint, distinct brain activity patterns that differ between groups of subjects; not to use the information to classify individuals. Here, we use joint Independent Component Analysis (jICA) within a Support Vector Machine (SVM) classification …


Immune Reconstitution But Persistent Activation After 48 Weeks Of Antiretroviral Therapy In Youth With Pre-Therapy Cd4 >350 In Atn 061., Bret J. Rudy, Bill G. Kapogiannis, Carol Worrell, Kathleen E. Squires, James Bethel, Su Li, Craig M. Wilson, Allison Agwu, Patricia Emmanuel, Georgine Price, Stephanie Hudey, Maureen M. Goodenow, John W. Sleasman May 2015

Immune Reconstitution But Persistent Activation After 48 Weeks Of Antiretroviral Therapy In Youth With Pre-Therapy Cd4 >350 In Atn 061., Bret J. Rudy, Bill G. Kapogiannis, Carol Worrell, Kathleen E. Squires, James Bethel, Su Li, Craig M. Wilson, Allison Agwu, Patricia Emmanuel, Georgine Price, Stephanie Hudey, Maureen M. Goodenow, John W. Sleasman

Department of Medicine Faculty Papers

BACKGROUND: Measures of immune outcomes in youth who initiate combination antiretroviral therapy (cART) early in HIV infection are limited.

DESIGN: Adolescent Trials Network 061 examined changes over 48 weeks of cART in T-cell subsets and markers of T-cell and macrophage activation in subjects with pre-therapy CD4 > 350 cells/mm. All subjects had optimal viral suppression from weeks 24 through 48.

METHODS: Subjects (n = 48) initiated cART with tenofovir/emtricitabine plus ritonavir-boosted atazanavir. Data were collected at baseline and weeks 12, 24, and 48. Trends were compared to uninfected controls.

RESULTS: Significant increases over 48 weeks were noted in all CD4 populations, …


The Human Motor System Alters Its Reaching Movement Plan For Task-Irrelevant, Positional Forces., Joshua G A Cashaback, Heather R Mcgregor, Paul L Gribble Apr 2015

The Human Motor System Alters Its Reaching Movement Plan For Task-Irrelevant, Positional Forces., Joshua G A Cashaback, Heather R Mcgregor, Paul L Gribble

Brain and Mind Institute Researchers' Publications

The minimum intervention principle and the uncontrolled manifold hypothesis state that our nervous system only responds to force perturbations and sensorimotor noise if they affect task success. This idea has been tested in muscle and joint coordinate frames and more recently using workspace redundancy (e.g., reaching to large targets). However, reaching studies typically involve spatial and or temporal constraints. Constrained reaches represent a small proportion of movements we perform daily and may limit the emergence of natural behavior. Using more relaxed constraints, we conducted two reaching experiments to test the hypothesis that humans respond to task-relevant forces and ignore task-irrelevant …


Deficits In Audiovisual Speech Perception In Normal Aging Emerge At The Level Of Whole-Word Recognition., Ryan A Stevenson, Caitlin E Nelms, Sarah H Baum, Lilia Zurkovsky, Morgan D Barense, Paul A Newhouse, Mark T Wallace Jan 2015

Deficits In Audiovisual Speech Perception In Normal Aging Emerge At The Level Of Whole-Word Recognition., Ryan A Stevenson, Caitlin E Nelms, Sarah H Baum, Lilia Zurkovsky, Morgan D Barense, Paul A Newhouse, Mark T Wallace

Brain and Mind Institute Researchers' Publications

Over the next 2 decades, a dramatic shift in the demographics of society will take place, with a rapid growth in the population of older adults. One of the most common complaints with healthy aging is a decreased ability to successfully perceive speech, particularly in noisy environments. In such noisy environments, the presence of visual speech cues (i.e., lip movements) provide striking benefits for speech perception and comprehension, but previous research suggests that older adults gain less from such audiovisual integration than their younger peers. To determine at what processing level these behavioral differences arise in healthy-aging populations, we administered …


Fusion Analysis Of First Episode Depression: Where Brain Shape Deformations Meet Local Composition Of Tissue., Mahdi Ramezani, Purang Abolmaesumi, Amir Tahmasebi, Rachael Bosma, Ryan Tong, Tom Hollenstein, Kate Harkness, Ingrid Johnsrude Jan 2015

Fusion Analysis Of First Episode Depression: Where Brain Shape Deformations Meet Local Composition Of Tissue., Mahdi Ramezani, Purang Abolmaesumi, Amir Tahmasebi, Rachael Bosma, Ryan Tong, Tom Hollenstein, Kate Harkness, Ingrid Johnsrude

Brain and Mind Institute Researchers' Publications

Computational neuroanatomical techniques that are used to evaluate the structural correlates of disorders in the brain typically measure regional differences in gray matter or white matter, or measure regional differences in the deformation fields required to warp individual datasets to a standard space. Our aim in this study was to combine measurements of regional tissue composition and of deformations in order to characterize a particular brain disorder (here, major depressive disorder). We use structural Magnetic Resonance Imaging (MRI) data from young adults in a first episode of depression, and from an age- and sex-matched group of non-depressed individuals, and create …


Genetic Modifiers Of Duchenne Muscular Dystrophy And Dilated Cardiomyopathy., Andrea Barp, Luca Bello, Luisa Politano, Paola Melacini, Chiara Calore, Eric P. Hoffman, +16 Additional Authors Jan 2015

Genetic Modifiers Of Duchenne Muscular Dystrophy And Dilated Cardiomyopathy., Andrea Barp, Luca Bello, Luisa Politano, Paola Melacini, Chiara Calore, Eric P. Hoffman, +16 Additional Authors

Genomics and Precision Medicine Faculty Publications

OBJECTIVE: Dilated cardiomyopathy (DCM) is a major complication and leading cause of death in Duchenne muscular dystrophy (DMD). DCM onset is variable, suggesting modifier effects of genetic or environmental factors. We aimed to determine if polymorphisms previously associated with age at loss of independent ambulation (LoA) in DMD (rs28357094 in the SPP1 promoter, rs10880 and the VTTT/IAAM haplotype in LTBP4) also modify DCM onset.

METHODS: A multicentric cohort of 178 DMD patients was genotyped by TaqMan assays. We performed a time-to-event analysis of DCM onset, with age as time variable, and finding of left ventricular ejection fraction < 50% and/or end diastolic volume > 70 mL/m2 as …


Developmental Differences In The Influence Of Phonological Similarity On Spoken Word Processing In Mandarin Chinese., Jeffrey G Malins, Danqi Gao, Ran Tao, James R Booth, Hua Shu, Marc F Joanisse, Li Liu, Amy S Desroches Nov 2014

Developmental Differences In The Influence Of Phonological Similarity On Spoken Word Processing In Mandarin Chinese., Jeffrey G Malins, Danqi Gao, Ran Tao, James R Booth, Hua Shu, Marc F Joanisse, Li Liu, Amy S Desroches

Brain and Mind Institute Researchers' Publications

The developmental trajectory of spoken word recognition has been well established in Indo-European languages, but to date remains poorly characterized in Mandarin Chinese. In this study, typically developing children (N=17; mean age 10; 5) and adults (N=17; mean age 24) performed a picture-word matching task in Mandarin while we recorded ERPs. Mismatches diverged from expectations in different components of the Mandarin syllable; namely, word-initial phonemes, word-final phonemes, and tone. By comparing responses to different mismatch types, we uncovered evidence suggesting that both children and adults process words incrementally. However, we also observed key developmental differences in how subjects treated onset …


Striatum In Stimulus-Response Learning Via Feedback And In Decision Making., Nole M Hiebert, Andrew Vo, Adam Hampshire, Adrian M Owen, Ken N Seergobin, Penny A Macdonald Nov 2014

Striatum In Stimulus-Response Learning Via Feedback And In Decision Making., Nole M Hiebert, Andrew Vo, Adam Hampshire, Adrian M Owen, Ken N Seergobin, Penny A Macdonald

Brain and Mind Institute Researchers' Publications

Cognitive deficits are recognized in Parkinson's disease. Understanding cognitive functions mediated by the striatum can clarify some of these impairments and inform treatment strategies. The dorsal striatum, a region impaired in Parkinson's disease, has been implicated in stimulus-response learning. However, most investigations combine acquisition of associations between stimuli, responses, or outcomes (i.e., learning) and expression of learning through response selection and decision enactment, confounding these separate processes. Using neuroimaging, we provide evidence that dorsal striatum does not mediate stimulus-response learning from feedback but rather underlies decision making once associations between stimuli and responses are learned. In the experiment, 11 males …


Mirror Reversal And Visual Rotation Are Learned And Consolidated Via Separate Mechanisms: Recalibrating Or Learning De Novo?, Sebastian Telgen, Darius Parvin, Jörn Diedrichsen Oct 2014

Mirror Reversal And Visual Rotation Are Learned And Consolidated Via Separate Mechanisms: Recalibrating Or Learning De Novo?, Sebastian Telgen, Darius Parvin, Jörn Diedrichsen

Brain and Mind Institute Researchers' Publications

Motor learning tasks are often classified into adaptation tasks, which involve the recalibration of an existing control policy (the mapping that determines both feedforward and feedback commands), and skill-learning tasks, requiring the acquisition of new control policies. We show here that this distinction also applies to two different visuomotor transformations during reaching in humans: Mirror-reversal (left-right reversal over a mid-sagittal axis) of visual feedback versus rotation of visual feedback around the movement origin. During mirror-reversal learning, correct movement initiation (feedforward commands) and online corrections (feedback responses) were only generated at longer latencies. The earliest responses were directed into a nonmirrored …


Clinical And Biochemical Function Of Polymorphic Nr0b1 Ggaa-Microsatellites In Ewing Sarcoma: A Report From The Children's Oncology Group., Michael J. Monument, Kirsten M. Johnson, Elizabeth Mcilvaine, Lisa Abegglen, W. Scott Watkins, Lynn B. Jorde, Richard B. Womer, Natalie Beeler, Laura Monovich, Elizabeth R. Lawlor, Julia A. Bridge, Joshua D. Schiffman, Mark D Krailo, R. Lor Randall, Stephen L. Lessnick Aug 2014

Clinical And Biochemical Function Of Polymorphic Nr0b1 Ggaa-Microsatellites In Ewing Sarcoma: A Report From The Children's Oncology Group., Michael J. Monument, Kirsten M. Johnson, Elizabeth Mcilvaine, Lisa Abegglen, W. Scott Watkins, Lynn B. Jorde, Richard B. Womer, Natalie Beeler, Laura Monovich, Elizabeth R. Lawlor, Julia A. Bridge, Joshua D. Schiffman, Mark D Krailo, R. Lor Randall, Stephen L. Lessnick

Journal Articles: Pathology and Microbiology

BACKGROUND: The genetics involved in Ewing sarcoma susceptibility and prognosis are poorly understood. EWS/FLI and related EWS/ETS chimeras upregulate numerous gene targets via promoter-based GGAA-microsatellite response elements. These microsatellites are highly polymorphic in humans, and preliminary evidence suggests EWS/FLI-mediated gene expression is highly dependent on the number of GGAA motifs within the microsatellite.

OBJECTIVES: Here we sought to examine the polymorphic spectrum of a GGAA-microsatellite within the NR0B1 promoter (a critical EWS/FLI target) in primary Ewing sarcoma tumors, and characterize how this polymorphism influences gene expression and clinical outcomes.

RESULTS: A complex, bimodal pattern of EWS/FLI-mediated gene expression was observed …


Continuous Executive Function Disruption Interferes With Application Of An Information Integration Categorization Strategy., Sarah J Miles, Kazunaga Matsuki, John Paul Minda Jul 2014

Continuous Executive Function Disruption Interferes With Application Of An Information Integration Categorization Strategy., Sarah J Miles, Kazunaga Matsuki, John Paul Minda

Brain and Mind Institute Researchers' Publications

Category learning is often characterized as being supported by two separate learning systems. A verbal system learns rule-defined (RD) categories that can be described using a verbal rule and relies on executive functions (EFs) to learn via hypothesis testing. A nonverbal system learns non-rule-defined (NRD) categories that cannot be described by a verbal rule and uses automatic, procedural learning. The verbal system is dominant in that adults tend to use it during initial learning but may switch to the nonverbal system when the verbal system is unsuccessful. The nonverbal system has traditionally been thought to operate independently of EFs, but …


Effector-Independent Motor Sequence Representations Exist In Extrinsic And Intrinsic Reference Frames., Tobias Wiestler, Sheena Waters-Metenier, Jörn Diedrichsen Apr 2014

Effector-Independent Motor Sequence Representations Exist In Extrinsic And Intrinsic Reference Frames., Tobias Wiestler, Sheena Waters-Metenier, Jörn Diedrichsen

Brain and Mind Institute Researchers' Publications

Many daily activities rely on the ability to produce meaningful sequences of movements. Motor sequences can be learned in an effector-specific fashion (such that benefits of training are restricted to the trained hand) or an effector-independent manner (meaning that learning also facilitates performance with the untrained hand). Effector-independent knowledge can be represented in extrinsic/world-centered or in intrinsic/body-centered coordinates. Here, we used functional magnetic resonance imaging (fMRI) and multivoxel pattern analysis to determine the distribution of intrinsic and extrinsic finger sequence representations across the human neocortex. Participants practiced four sequences with one hand for 4 d, and then performed these sequences …


Maternal Biomarkers Of Endothelial Dysfunction And Preterm Delivery, Xinhua Chen, Theresa O Scholl Jan 2014

Maternal Biomarkers Of Endothelial Dysfunction And Preterm Delivery, Xinhua Chen, Theresa O Scholl

Rowan-Virtua School of Osteopathic Medicine Departmental Research

BACKGROUND: Endothelial dysfunction is key to the development of atherosclerosis. Preterm delivery foreshadows later maternal cardiovascular disease (CVD), but it is not known if endothelial dysfunction also occurs. We prospectively measured circulating biomarkers of endothelial dysfunction in pregnant women with preterm or term delivery.

METHODS: We conducted a case-control study nested within a large prospective epidemiological study of young, generally healthy pregnant women. Women who delivered preterm (gestation, n = 240) and controls who delivered at term (n = 439) were included. Pregnancies complicated by preeclampsia were analyzed separately. Circulating endothelial dysfunction biomarkers included soluble intercellular adhesion molecule-1 (sICAM-1), vascular …


Response Of An Aggressive Periosteal Aneurysmal Bone Cyst (Abc) Of The Radius To Denosumab Therapy., Chantal Pauli, Bruno Fuchs, Christian Pfirrmann, Julia A. Bridge, Silvia Hofer, Beata Bode Jan 2014

Response Of An Aggressive Periosteal Aneurysmal Bone Cyst (Abc) Of The Radius To Denosumab Therapy., Chantal Pauli, Bruno Fuchs, Christian Pfirrmann, Julia A. Bridge, Silvia Hofer, Beata Bode

Journal Articles: Pathology and Microbiology

Aneurysmal bone cyst (ABC), once considered a reactive lesion, has been proven to be a neoplasia characterized by rearrangements of the USP6-gene. Aggressive local growth and recurrences are common and therapeutic options may be limited due to the vicinity of crucial structures. We describe a case of a locally aggressive, multinucleated giant cell-containing lesion of the forearm of a 21-year old woman, treated with denosumab for recurrent, surgically uncontrollable disease. Under the influence of this RANKL inhibitor, the tumor showed a marked reduction of the content of the osteoclastic giant cells and an extensive metaplastic osteoid production leading to the …


Bihemispheric Transcranial Direct Current Stimulation Enhances Effector-Independent Representations Of Motor Synergy And Sequence Learning., Sheena Waters-Metenier, Masud Husain, Tobias Wiestler, Jörn Diedrichsen Jan 2014

Bihemispheric Transcranial Direct Current Stimulation Enhances Effector-Independent Representations Of Motor Synergy And Sequence Learning., Sheena Waters-Metenier, Masud Husain, Tobias Wiestler, Jörn Diedrichsen

Brain and Mind Institute Researchers' Publications

Complex manual tasks-everything from buttoning up a shirt to playing the piano-fundamentally involve two components: (1) generating specific patterns of muscle activity (here, termed "synergies"); and (2) stringing these into purposeful sequences. Although transcranial direct current stimulation (tDCS) of the primary motor cortex (M1) has been found to increase the learning of motor sequences, it is unknown whether it can similarly facilitate motor synergy learning. Here, we determined the effects of tDCS on the learning of motor synergies using a novel hand configuration task that required the production of difficult muscular activation patterns. Bihemispheric tDCS was applied to M1 of …


What Are Ventilation Defects In Asthma?, Sarah Svenningsen, Miranda Kirby, Danielle Starr, Harvey O Coxson, Nigel A M Paterson, David G Mccormack, Grace Parraga Jan 2014

What Are Ventilation Defects In Asthma?, Sarah Svenningsen, Miranda Kirby, Danielle Starr, Harvey O Coxson, Nigel A M Paterson, David G Mccormack, Grace Parraga

Medical Biophysics Publications

BACKGROUND: Hyperpolarised (3)He MRI provides a way to visualise regional pulmonary functional abnormalities that in asthma are thought to be related to airway morphological abnormalities. However, the exact aetiology of ventilation defects in asthma is not well understood.

OBJECTIVE: To better understand the determinants of ventilation defects in asthma, we evaluated well-established clinical as well as (3)He MRI and X-ray CT airway measurements in healthy subjects and subjects with asthma.

METHODS: Thirty-four subjects (n=26 subjects with asthma, n=8 healthy volunteers) underwent MRI, spirometry, plethysmography, fraction of exhaled nitric oxide analysis, methacholine challenge and CT for a region-of-interest proximal to ventilation …


A Multivariate Method To Determine The Dimensionality Of Neural Representation From Population Activity., Jörn Diedrichsen, Tobias Wiestler, Naveed Ejaz Aug 2013

A Multivariate Method To Determine The Dimensionality Of Neural Representation From Population Activity., Jörn Diedrichsen, Tobias Wiestler, Naveed Ejaz

Brain and Mind Institute Researchers' Publications

How do populations of neurons represent a variable of interest? The notion of feature spaces is a useful concept to approach this question: According to this model, the activation patterns across a neuronal population are composed of different pattern components. The strength of each of these components varies with one latent feature, which together are the dimensions along which the population represents the variable. Here we propose a new method to determine the number of feature dimensions that best describes the activation patterns. The method is based on Gaussian linear classifiers that use only the first d most important pattern …


Hippocampal Functional Connectivity Patterns During Spatial Working Memory Differ In Right Versus Left Temporal Lobe Epilepsy., Gaelle Eve Doucet, Karol Osipowicz, Ashwini Sharan Md, Michael R Sperling, Joseph I Tracy Aug 2013

Hippocampal Functional Connectivity Patterns During Spatial Working Memory Differ In Right Versus Left Temporal Lobe Epilepsy., Gaelle Eve Doucet, Karol Osipowicz, Ashwini Sharan Md, Michael R Sperling, Joseph I Tracy

Department of Neurology Faculty Papers

Temporal lobe epilepsy (TLE), affecting the medial temporal lobe, is a disorder that affects not just episodic memory but also working memory (WM). However, the exact nature of hippocampal-related network activity in visuospatial WM remains unclear. To clarify this, we utilized a functional connectivity (FC) methodology to investigate hippocampal network involvement during the encoding phase of a functional magnetic resonance imaging (fMRI) visuospatial WM task in right and left TLE patients. Specifically, we assessed the relation between FC within right and left hippocampus-seeded networks, and patient performance (rate of correct responses) during the encoding phase of a block span WM …


Two Distinct Ipsilateral Cortical Representations For Individuated Finger Movements., Jörn Diedrichsen, Tobias Wiestler, John W Krakauer Jun 2013

Two Distinct Ipsilateral Cortical Representations For Individuated Finger Movements., Jörn Diedrichsen, Tobias Wiestler, John W Krakauer

Brain and Mind Institute Researchers' Publications

Movements of the upper limb are controlled mostly through the contralateral hemisphere. Although overall activity changes in the ipsilateral motor cortex have been reported, their functional significance remains unclear. Using human functional imaging, we analyzed neural finger representations by studying differences in fine-grained activation patterns for single isometric finger presses. We demonstrate that cortical motor areas encode ipsilateral movements in 2 fundamentally different ways. During unimanual ipsilateral finger presses, primary sensory and motor cortices show, underneath global suppression, finger-specific activity patterns that are nearly identical to those elicited by contralateral mirror-symmetric action. This component vanishes when both motor cortices are …


Decoding The Neural Mechanisms Of Human Tool Use., Jason P Gallivan, D Adam Mclean, Kenneth F Valyear, Jody C Culham May 2013

Decoding The Neural Mechanisms Of Human Tool Use., Jason P Gallivan, D Adam Mclean, Kenneth F Valyear, Jody C Culham

Brain and Mind Institute Researchers' Publications

Sophisticated tool use is a defining characteristic of the primate species but how is it supported by the brain, particularly the human brain? Here we show, using functional MRI and pattern classification methods, that tool use is subserved by multiple distributed action-centred neural representations that are both shared with and distinct from those of the hand. In areas of frontoparietal cortex we found a common representation for planned hand- and tool-related actions. In contrast, in parietal and occipitotemporal regions implicated in hand actions and body perception we found that coding remained selectively linked to upcoming actions of the hand whereas …


The Human Brain Processes Syntax In The Absence Of Conscious Awareness., Laura Batterink, Helen J Neville May 2013

The Human Brain Processes Syntax In The Absence Of Conscious Awareness., Laura Batterink, Helen J Neville

Brain and Mind Institute Researchers' Publications

Syntax is the core computational component of language. A longstanding idea about syntactic processing is that it is generally not available to conscious access, operating autonomously and automatically. However, there is little direct neurocognitive evidence on this issue. By measuring event-related potentials while human observers performed a novel cross-modal distraction task, we demonstrated that syntactic violations that were not consciously detected nonetheless produced a characteristic early neural response pattern, and also significantly delayed reaction times to a concurrent task. This early neural response was distinct from later neural activity that was observed only to syntactic violations that were consciously detected. …


Cytoplasmic Localization Of Alteration/Deficiency In Activation 3 (Ada3) Predicts Poor Clinical Outcome In Breast Cancer Patients., Sameer Mirza, Emad A. Rakha, Alaa Alshareeda, Shakur Mohibi, Xiangshan Zhao, Bryan J. Katafiasz, Jun Wang, Channabasavaiah B. Gurumurthy, Aditya Bele, Ian O. Ellis, Andrew R. Green, Hamid Band, Vimla Band Feb 2013

Cytoplasmic Localization Of Alteration/Deficiency In Activation 3 (Ada3) Predicts Poor Clinical Outcome In Breast Cancer Patients., Sameer Mirza, Emad A. Rakha, Alaa Alshareeda, Shakur Mohibi, Xiangshan Zhao, Bryan J. Katafiasz, Jun Wang, Channabasavaiah B. Gurumurthy, Aditya Bele, Ian O. Ellis, Andrew R. Green, Hamid Band, Vimla Band

Journal Articles: Genetics, Cell Biology & Anatomy

Transcriptional activation by estrogen receptor (ER) is a key step to breast oncogenesis. Given previous findings that ADA3 is a critical component of HAT complexes that regulate ER function and evidence that overexpression of other ER coactivators such as SRC-3 is associated with clinical outcomes in breast cancer, the current study was designed to assess the potential significance of ADA3 expression/localization in human breast cancer patients. In this study, we analyzed ADA3 expression in breast cancer tissue specimens and assessed the correlation of ADA3 staining with cancer progression and patient outcome. Tissue microarrays prepared from large series of breast cancer …


A Genome-Wide Methylation Study On Essential Hypertension In Young African American Males., Xiaoling Wang, Bonita Falkner, Haidong Zhu, Huidong Shi, Shaoyong Su, Xiaojing Xu, Ashok Kumar Sharma, Yanbin Dong, Frank Treiber, Bernard Gutin, Gregory Harshfield, Harold Snieder Jan 2013

A Genome-Wide Methylation Study On Essential Hypertension In Young African American Males., Xiaoling Wang, Bonita Falkner, Haidong Zhu, Huidong Shi, Shaoyong Su, Xiaojing Xu, Ashok Kumar Sharma, Yanbin Dong, Frank Treiber, Bernard Gutin, Gregory Harshfield, Harold Snieder

Department of Medicine Faculty Papers

OBJECTIVE: There is emerging evidence from animal studies suggesting a key role for methylation in the pathogenesis of essential hypertension. However, to date, very few studies have investigated the role of methylation in the development of human hypertension, and none has taken a genome-wide approach. Based on the recent studies that highlight the involvement of inflammation in the development of hypertension, we hypothesize that changes in DNA methylation of leukocytes are involved in the pathogenesis of hypertension.

METHOD & RESULTS: We conducted a genome-wide methylation analysis on 8 hypertensive cases and 8 normotensive age-matched controls aged 14-23 years and performed …


Expanding The Basic Science Debate: The Role Of Physics Knowledge In Interpreting Clinical Findings., Mark Goldszmidt, John Paul Minda, Sarah L Devantier, Aimee L Skye, Nicole N Woods Oct 2012

Expanding The Basic Science Debate: The Role Of Physics Knowledge In Interpreting Clinical Findings., Mark Goldszmidt, John Paul Minda, Sarah L Devantier, Aimee L Skye, Nicole N Woods

Brain and Mind Institute Researchers' Publications

Current research suggests a role for biomedical knowledge in learning and retaining concepts related to medical diagnosis. However, learning may be influenced by other, non-biomedical knowledge. We explored this idea using an experimental design and examined the effects of causal knowledge on the learning, retention, and interpretation of medical information. Participants studied a handout about several respiratory disorders and how to interpret respiratory exam findings. The control group received the information in standard "textbook" format and the experimental group was presented with the same information as well as a causal explanation about how sound travels through lungs in both the …