Neurosciences Commons^™

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.

Corrigendum To "Overlapping And Distinct Brain Regions Involved In Estimating The Spatial Position Of Numerical And Non-Numerical Magnitudes: An Fmri Study" [Neuropsychologia 51(5) (2013) 979-989], Stephan E. Vogel, Roland H. Grabner, Michael Schneider, Robert S. Siegler, Daniel Ansari

Brain and Mind Institute Researchers' Publications

No abstract provided.

Combined Chondroitinase And Klf7 Expression Reduce Net Retraction Of Sensory And Cst Axons From Sites Of Spinal Injury, Zimei Wang, Kristen N. Winsor, Evan Hess, Murray G. Blackmore, Christopher Nienhaus

Biomedical Sciences Faculty Research and Publications

Axon regeneration in the central nervous system is limited both by inhibitory extracellular cues and by an intrinsically low capacity for axon growth in some CNS populations. Chondroitin sulfate proteoglycans (CSPGs) are well-studied inhibitors of axon growth in the CNS, and degradation of CSPGs by chondroitinase has been shown to improve the extension of injured axons. Alternatively, axon growth can be improved by targeting the neuron-intrinsic growth capacity through forced expression of regeneration-associated transcription factors. For example, a transcriptionally active chimera of Krüppel-like Factor 7 (KLF7) and a VP16 domain improves axon growth when expressed in corticospinal tract neurons. Here …

Reduction Of Cocaine-Induced Locomotor Effects By Enriched Environment Is Associated With Cell-Specific Accumulation Of Δfosb In Striatal And Cortical Subregions, Audrey Lafragette, Michael T. Bardo, Virginie Lardeux, Marcello Solinas, Nathalie Thiriet

Psychology Faculty Publications

Background: Early exposure to enriched environments has been shown to decrease the locomotor effects induced by repeated injections of cocaine and modify basal and cocaine-induced total protein levels of the transcription factor ΔFosB in the whole striatum of mice. In this study, we aimed at characterizing whether the profile of ΔFosB accumulation induced by enriched environments and cocaine would be similar or different in terms of brain areas and cell type.

Methods: We used mice expressing the eGFP protein in D1 receptor positive (D1R(+)) neurons to determine whether ΔFosB induced by enriched environment or cocaine injections (5×15 mg/kg) would occur …

Remodeling Brain Activity By Repetitive Cervicothoracic Transspinal Stimulation After Human Spinal Cord Injury, Lynda M. Murray, Maria Knikou

Publications and Research

Interventions that can produce targeted brain plasticity after human spinal cord injury (SCI) are needed for restoration of impaired movement in these patients. In this study, we tested the effects of repetitive cervicothoracic transspinal stimulation in one person with cervical motor incomplete SCI on cortical and corticospinal excitability, which were assessed via transcranial magnetic stimulation with paired and single pulses, respectively. We found that repetitive cervicothoracic transspinal stimulation potentiated intracortical facilitation in flexor and extensor wrist muscles, recovered intracortical inhibition in the more impaired wrist flexor muscle, increased corticospinal excitability bilaterally, and improved voluntary muscle strength. These effects may have …

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 …

Map7 Regulates Axon Collateral Branch Development In Dorsal Root Ganglion Neurons., Stephen R Tymanskyj, Benjamin Yang, Aditi Falnikar, Angelo C Lepore, Le Ma

Department of Neuroscience Faculty Papers

Collateral branches from axons are key components of functional neural circuits that allow neurons to connect with multiple synaptic targets. Like axon growth and guidance, formation of collateral branches depends on the regulation of microtubules, but how such regulation is coordinated to ensure proper circuit development is not known. Based on microarray analysis, we have identified a role for microtubule-associated protein 7 (MAP7) during collateral branch development of dorsal root ganglion (DRG) sensory neurons. We show that MAP7 is expressed at the onset of collateral branch formation. Perturbation of its expression by overexpression or shRNA knockdown alters axon branching in …

Regulation Of Trpm7 By Cytosolic Mg2+ And Ph: Insights From Vsp Expression, Pavani Beesetty, Krystyna Blanka Wieczerzak, Tatyana Zhelay, Taku Kaitsuka, Masayuki Matsushita, J. Ashot Kozak

Neuroscience, Cell Biology & Physiology Faculty Publications

TRPM7 is an ion channel/protein kinase belonging to TRP melastatin and eEF2 kinase families. Under physiological conditions, most native TRPM7 channels are inactive, due to inhibition by cytoplasmic Mg2+, protons and polyamines. ITRPM7 is strongly potentiated when cell cytosol is depleted of Mg2+ or alkalinized. In Jurkat T cells, Mg2+ inhibition involves a high and a low affinity inhibitor sites, whereas proton inhibition involves only one site. Like many other TRP channels, TRPM7 is activated by PI(4,5)P2 and suppressed by its hydrolysis. Here we examined Mg2+ and pH inhibition of native TRPM7 channels in HEK293 cells overexpressing voltage-sensitive phospholipid phosphatase …

Adolescent Cannabinoid Exposure Induces A Persistent Sub-Cortical Hyper-Dopaminergic State And Associated Molecular Adaptations In The Prefrontal Cortex., Justine Renard, Laura G Rosen, Michael Loureiro, Cleusa De Oliveira, Susanne Schmid, Walter J Rushlow, Steven R Laviolette

Brain and Mind Institute Researchers' Publications

Considerable evidence suggests that adolescent exposure to delta-9-tetrahydrocanabinol (THC), the psychoactive component in marijuana, increases the risk of developing schizophrenia-related symptoms in early adulthood. In the present study, we used a combination of behavioral and molecular analyses with in vivo neuronal electrophysiology to compare the long-term effects of adolescent versus adulthood THC exposure in rats. We report that adolescent, but not adult, THC exposure induces long-term neuropsychiatric-like phenotypes similar to those observed in clinical populations. Thus, adolescent THC exposure induced behavioral abnormalities resembling positive and negative schizophrenia-related endophenotypes and a state of neuronal hyperactivity in the mesocorticolimbic dopamine (DA) pathway. …

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 …

Corticosterone Potentiation Of Cocaine-Induced Reinstatement Of Conditioned Place Preference In Mice Is Mediated By Blockade Of The Organic Cation Transporter 3, Jayme R. Mcreynolds, Analisa Taylor, Oliver Vranjkovic, Terra Ambrosius, Olivia Derricks, Brittany Nino, Beliz Kurtoglu, Robert A. Wheeler, David A. Baker, Paul J. Gasser, John R. Mantsch

Biomedical Sciences Faculty Research and Publications

The mechanisms by which stressful life events increase the risk of relapse in recovering cocaine addicts are not well understood. We previously reported that stress, via elevated corticosterone, potentiates cocaine-primed reinstatement of cocaine seeking following self-administration in rats and that this potentiation appears to involve corticosterone-induced blockade of dopamine clearance via the organic cation transporter 3 (OCT3). In the present study, we use a conditioned place preference/reinstatement paradigm in mice to directly test the hypothesis that corticosterone potentiates cocaine-primed reinstatement by blockade of OCT3. Consistent with our findings following self-administration in rats, pretreatment of male C57/BL6 mice with corticosterone (using …

Neurovascular Astrocyte Degeneration In The Hyperhomocysteinemia Model Of Vascular Cognitive Impairment And Dementia (Vcid), Tiffany L. Sudduth, Erica M. Weekman, Brittani Rae Price, Jennifer L. Gooch, Abigail E. Woolums, Christopher M. Norris, Donna M. Wilcock

Sanders-Brown Center on Aging Faculty Publications

Vascular cognitive impairment and dementia (VCID) is the second leading cause of dementia behind Alzheimer’s disease (AD) and is a frequent co-morbidity with AD. Despite its prevalence, little is known about the molecular mechanisms underlying the cognitive dysfunction resulting from cerebrovascular disease. Astrocytic end-feet almost completely surround intraparenchymal blood vessels in the brain and express a variety of channels and markers indicative of their specialized functions in the maintenance of ionic and osmotic homeostasis and gliovascular signaling. These functions are mediated by end-foot enrichment of the aquaporin 4 water channel (AQP4), the inward rectifying potassium channel Kir4.1 and the calcium-dependent …

Analysis Of Proprioceptive Sensory Innervation Of The Mouse Soleus: A Whole-Mount Muscle Approach, Martha Jean Sonner, Marie C. Walters, David R. Ladle

Neuroscience, Cell Biology & Physiology Faculty Publications

Muscle proprioceptive afferents provide feedback critical for successful execution of motor tasks via specialized mechanoreceptors housed within skeletal muscles: muscle spindles, supplied by group Ia and group II afferents, and Golgi tendon organs, supplied by group Ib afferents. The morphology of these proprioceptors and their associated afferents has been studied extensively in the cat soleus, and to a lesser degree, in the rat; however, quantitative analyses of proprioceptive innervation in the mouse soleus are comparatively limited. The present study employed genetically-encoded fluorescent reporting systems to label and analyze muscle spindles, Golgi tendon organs, and the proprioceptive sensory neuron subpopulations supplying …

Regulation Of Sleep Plasticity By A Thermo-Sensitive Circuit In Drosophila., Angelique Lamaze, Arzu Öztürk-Çolak, Robin Fischer, Nicolai Peschel, Kyunghee Koh, James E.C. Jepson

Department of Neuroscience Faculty Papers

Sleep is a highly conserved and essential behaviour in many species, including the fruit fly Drosophila melanogaster. In the wild, sensory signalling encoding environmental information must be integrated with sleep drive to ensure that sleep is not initiated during detrimental conditions. However, the molecular and circuit mechanisms by which sleep timing is modulated by the environment are unclear. Here we introduce a novel behavioural paradigm to study this issue. We show that in male fruit flies, onset of the daytime siesta is delayed by ambient temperatures above 29 °C. We term this effect Prolonged Morning Wakefulness (PMW). We show that …

Human Ipsc-Derived Cerebellar Neurons From A Patient With Ataxia-Telangiectasia Reveal Disrupted Gene Regulatory Networks, Sam Nayler, Joseph Powell, Darya Vanichkina, Othmar Korn, Christine Wells, Ryan J. Taft, +Several Additional Authors

Genomics and Precision Medicine Faculty Publications

Ataxia-telangiectasia (A-T) is a rare genetic disorder caused by loss of function of the ataxia-telangiectasia-mutated kinase and is characterized by a predisposition to cancer, pulmonary disease, immune deficiency and progressive degeneration of the cerebellum. As animal models do not faithfully recapitulate the neurological aspects, it remains unclear whether cerebellar degeneration is a neurodevelopmental or neurodegenerative phenotype. To address the necessity for a human model, we first assessed a previously published protocol for the ability to generate cerebellar neuronal cells, finding it gave rise to a population of precursors highly enriched for markers of the early hindbrain such as EN1 and …

Visual Neurons In The Superior Colliculus Innervated By Islet2+ Or Islet2− Retinal Ganglion Cells Display Distinct Tuning Properties, Rachel Kay, Jason W. Triplett

Pediatrics Faculty Publications

Throughout the visual system, different subtypes of neurons are tuned to distinct aspects of the visual scene, establishing parallel circuits. Defining the mechanisms by which such tuning arises has been a long-standing challenge for neuroscience. To investigate this, we have focused on the retina’s projection to the superior colliculus (SC), where multiple visual neuron subtypes have been described. The SC receives inputs from a variety of retinal ganglion cell (RGC) subtypes; however, which RGCs drive the tuning of different SC neurons remains unclear. Here, we pursued a genetic approach that allowed us to determine the tuning properties of neurons innervated …

Survival And Growth Of C57bl/6j Mice Lacking The Bk Channel, Kcnma1: Lower Adult Body Weight Occurs Together With Higher Body Fat, Susan T. Halm, Michael A. Bottomley, Mohammed M. Almutairi, Mauricio Di Fulvio, Dan R. Halm

Neuroscience, Cell Biology & Physiology Faculty Publications

Big conductance potassium (BK) channels contribute to K⁺ flow and electrical behavior in many cell types. Mice made null for the gene (Kcnma1) producing the BK channel (BK^KO) exhibit numerous deficits in physiological functions. Breeding mice lacking a single allele of Kcnma1 (C57BL/6J background) had litter sizes of approximately eight pups. For the period of maternal care (P0– P21), pup deaths peaked at P1 with a second less severe interval of death peaking near P13. Early deaths were twice as likely during a 20-month period of building construction compared with the quiescent period after cessation of construction. Births …

Hippocampal Neurogenesis And Volume In Migrating And Wintering Semipalmated Sandpipers (Calidris Pusilla)., Nara Gyzely De Morais Magalhães, Cristovam Guerreiro Diniz, Daniel Guerreiro Diniz, Ediely Pereira Henrique, Patrick Douglas Corrêa Pereira, Isis Ananda Matos Moraes, Mauro André Damasceno De Melo, David Francis Sherry, Cristovam Wanderley Picanço Diniz

Brain and Mind Institute Researchers' Publications

Long distance migratory birds find their way by sensing and integrating information from a large number of cues in their environment. These cues are essential to navigate over thousands of kilometers and reach the same breeding, stopover, and wintering sites every year. The semipalmated sandpiper (Calidris pusilla) is a long-distance migrant that breeds in the arctic tundra of Canada and Alaska and winters on the northeast coast of South America. Its fall migration includes a 5,300-kilometer nonstop flight over the Atlantic Ocean. The avian hippocampus has been proposed to play a central role in the integration of multisensory spatial information …

Are There Place Cells In The Avian Hippocampus?, David F Sherry, Stephanie L Grella, Mélanie F Guigueno, David J White, Diano F Marrone

Brain and Mind Institute Researchers' Publications

Birds possess a hippocampus that serves many of the same spatial and mnemonic functions as the mammalian hippocampus but achieves these outcomes with a dramatically different neuroanatomical organization. The properties of spatially responsive neurons in birds and mammals are also different. Much of the contemporary interest in the role of the mammalian hippocampus in spatial representation dates to the discovery of place cells in the rat hippocampus. Since that time, cells that respond to head direction and cells that encode a grid-like representation of space have been described in the rat brain. Research with homing pigeons has discovered hippocampal cells, …

Hippocampal Astrocytes In Migrating And Wintering Semipalmated Sandpiper, Dario Carvalho-Paulo, Nara G De Morais Magalhães, Diego De Almeida Miranda, Daniel G Diniz, Ediely P Henrique, Isis A M Moraes, Patrick D C Pereira, Mauro A D De Melo, Camila M De Lima, Marcus A De Oliveira, Cristovam Guerreiro-Diniz, David F Sherry, Cristovam W P Diniz

Brain and Mind Institute Researchers' Publications

Seasonal migratory birds return to the same breeding and wintering grounds year after year, and migratory long-distance shorebirds are good examples of this. These tasks require learning and long-term spatial memory abilities that are integrated into a navigational system for repeatedly locating breeding, wintering, and stopover sites. Previous investigations focused on the neurobiological basis of hippocampal plasticity and numerical estimates of hippocampal neurogenesis in birds but only a few studies investigated potential contributions of glial cells to hippocampal-dependent tasks related to migration. Here we hypothesized that the astrocytes of migrating and wintering birds may exhibit significant morphological and numerical differences …