Medicine and Health Sciences Commons^™

Dynamics Of Alpha Control: Preparatory Suppression Of Posterior Alpha Oscillations By Frontal Modulators Revealed With Combined Eeg And Event-Related Optical Signal, Kyle E. Mathewson, Diane M. Beck, Tony Ro, Edward L. Maclin, Kathy A. Low, Monica Fabiani, Gabriele Gratton

Publications and Research

We investigated the dynamics of brain processes facilitating conscious experience of external stimuli. Previously, we proposed that alpha (8–12 Hz) oscillations, which fluctuate with both sustained and directed attention, represent a pulsed inhibition of ongoing sensory brain activity. Here we tested the prediction that inhibitory alpha oscillations in visual cortex are modulated by top–down signals from frontoparietal attention networks. We measured modulations in phase-coherent alpha oscillations from superficial frontal, parietal, and occipital cortices using the event-related optical signal (EROS), a measure of neuronal activity affording high spatiotemporal resolution, along with concurrently recorded EEG, while participants performed a visual target detection …

Developmental Stress, Condition, And Birdsong: A Case Study In Song Sparrows., Kim L Schmidt, Elizabeth A Macdougall-Shackleton, Shawn P Kubli, Scott A Macdougall-Shackleton

Brain and Mind Institute Researchers' Publications

Sexual-selection theory posits that ornaments and displays can reflect a signaler's condition, which in turn is affected both by recent and developmental conditions. Moreover, developmental conditions can induce correlations between sexually selected and other traits if both types of traits exhibit developmental phenotypic plasticity in response to stressors. Thus, sexually selected traits may reflect recent and/or developmental characteristics of signalers. Here, we review data on the relationships between birdsong, a sexually selected trait, and developmental and current condition of birds from a long-term study of a population of song sparrows (Melospiza melodia). Field studies of free-living birds indicate that the …

Dopaminergic Therapy Affects Learning And Impulsivity In Parkinson's Disease., Nole M Hiebert, Ken N Seergobin, Andrew Vo, Hooman Ganjavi, Penny A Macdonald

Brain and Mind Institute Researchers' Publications

OBJECTIVE: The aim was to examine the effect of dopaminergic medication on stimulus-response learning versus performing decisions based on learning.

METHOD: To see the effect of dopaminergic therapy on stimulus-response learning and response selection, participants with Parkinson's disease (PD) were either tested on and/or off their prescribed dose of dopaminergic therapy during different testing days. Forty participants with PD and 34 healthy controls completed the experiment on consecutive days. On Day 1, participants learned to associate abstract images with spoken, "right" or "left" responses via feedback (Session 1). On Day 2, participants recalled these responses (Session 2) and indicated the …

“Me & My Brain”: Exposing NeuroscienceʼS Closet Dualism, Liad Mudrik, Uri Maoz

Psychology Faculty Articles and Research

Our intuitive concept of the relations between brain and mind is increasingly challenged by the scientific world view. Yet, although few neuroscientists openly endorse Cartesian dualism, careful reading reveals dualistic intuitions in prominent neuroscientific texts. Here, we present the “double-subject fallacy”: treating the brain and the entire person as two independent subjects who can simultaneously occupy divergent psychological states and even have complex interactions with each other—as in “my brain knew before I did.” Although at first, such writing may appear like harmless, or even cute, shorthand, a closer look suggests that it can be seriously misleading. Surprisingly, this confused …

Swimming Against The Tide: Investigations Of The C-Bouton Synapse, Adam S. Deardorff, Shannon H. Romer, Patrick M. Sonner, Robert E. W. Fyffe

Neuroscience, Cell Biology & Physiology Faculty Publications

C-boutons are important cholinergic modulatory loci for state-dependent alterations in motoneuron firing rate. m2 receptors are concentrated postsynaptic to C-boutons, and m2 receptor activation increases motoneuron excitability by reducing the action potential afterhyperpolarization. Here, using an intensive review of the current literature as well as data from our laboratory, we illustrate that C-bouton postsynaptic sites comprise a unique structural/functional domain containing appropriate cellular machinery (a “signaling ensemble”) for cholinergic regulation of outward K⁺ currents. Moreover, synaptic reorganization at these critical sites has been observed in a variety of pathologic states. Yet despite recent advances, there are still great challenges …

Stress-Induced Cocaine Seeking Requires A Beta-2 Adrenergic Receptor-Regulated Pathway From The Ventral Bed Nucleus Of The Stria Terminalis That Regulates Crf Actions In The Ventral Tegmental Area, Oliver Vranjkovic, Paul J. Gasser, Clayton H. Gerndt, David A. Baker, John R. Mantsch

Biomedical Sciences Faculty Research and Publications

The ventral bed nucleus of the stria terminalis (vBNST) has been implicated in stress-induced cocaine use. Here we demonstrate that, in the vBNST, corticotropin releasing factor (CRF) is expressed in neurons that innervate the ventral tegmental area (VTA), a site where the CRF receptor antagonist antalarmin prevents the reinstatement of cocaine seeking by a stressor, intermittent footshock, following intravenous self-administration in rats. The vBNST receives dense noradrenergic innervation and expresses β adrenergic receptors (ARs). Footshock-induced reinstatement was prevented by bilateral intra-vBNST injection of the β-2 AR antagonist, ICI-118,551, but not the β-1 AR antagonist, betaxolol. Moreover, bilateral intra-vBNST injection of …

Cyclic Ovarian Hormone Modulation Of Supraspinal Δ9-Tetrahydrocannabinol-Induced Antinociception And Cannabinoid Receptor Binding In The Female Rat, Alexa A. Wakley, Alisha A. Mcbride, Linda K. Vaughn, Rebecca M. Craft

Biomedical Sciences Faculty Research and Publications

Estrous cycle-related fluctuations in delta-9-tetrahydrocannabinol (THC)-induced antinociception have been observed in the rat. The aim of this study was to determine which major ovarian hormone modulates the antinociceptive effects of i.c.v. THC, and whether hormone modulation of THC's behavioral effects could be due to changes in brain cannabinoid receptors (CBr). Vehicle (oil) or hormones (estradiol or progesterone, or both) were administered to female rats on days 3 and 7 post-ovariectomy. On the morning or afternoon of day 8 or day 9, vehicle or THC (100 μg) was administered i.c.v. Paw pressure, tail withdrawal, locomotor activity and catalepsy tests were conducted …

Role Of Astrocyte Network In Edema After Juvenile Traumatic Brain Injury, Andrew Minoru Fukuda

Loma Linda University Electronic Theses, Dissertations & Projects

Juvenile traumatic brain injury (jTBI) is the leading cause of death and disability in young children and adolescents. Despite its lasting detrimental effects on the developing brain, no pharmacological treatment exists. One of the pathological hallmarks of jTBI is edema. Astrocytes play a key role in the edema process, and have been hypothesized that numerous astrocyte networks allow communication and propagation of edema and secondary injury spread. Two key astrocyte proteins are hypothesized to have a central role in the edema process: Aquaporin 4 (AQP4) and Connexin 43 (Cx43). AQP4 is expressed extensively in astrocyte endfeet, which surrounds the blood …

Sharp Emergence Of Feature-Selective Sustained Activity Along The Dorsal Visual Pathway., Diego Mendoza-Halliday, Santiago Torres, Julio C Martinez-Trujillo

Brain and Mind Institute Researchers' Publications

Sustained activity encoding visual working memory representations has been observed in several cortical areas of primates. Where along the visual pathways this activity emerges remains unknown. Here we show in macaques that sustained spiking activity encoding memorized visual motion directions is absent in direction-selective neurons in early visual area middle temporal (MT). However, it is robustly present immediately downstream, in multimodal association area medial superior temporal (MST), as well as and in the lateral prefrontal cortex (LPFC). This sharp emergence of sustained activity along the dorsal visual pathway suggests a functional boundary between early visual areas, which encode sensory inputs, …

Investigation Of Sox9 Ablation On Neuroplasticity And Recovery After Ischemic Stroke, Bethany Robin Lenore Bass

Electronic Thesis and Dissertation Repository

Neuroplasticity is a key factor in post-stroke functional recovery. A chief inhibitor of post-stroke neuroplasticity is the expression of chondroitin sulfate proteoglycans (CSPGs). Recent research has shown that the transcription factor SOX9 is responsible for upregulating the expression of CSPGs in the injured central nervous system. Accordingly, CSPG levels are significantly lower in mice with the Sox9 gene conditionally knocked out. The purpose of this study was to determine how Sox9 ablation affects neuroplasticity and recovery after stroke. Behavioural test results revealed that Sox9 KO mice exhibited significantly improved functional recovery after stroke compared to controls. This correlated with increased …

Regulation Of Metabotropic Glutamate Receptor 5 Activity By Ca2+/Calmodulin-Dependent Protein Kinase Iiα, Fitore Raka

Electronic Thesis and Dissertation Repository

The metabotropic glutamate receptor 5 (mGluR5) is a GPCR coupled to the heterotrimeric G protein Ga_q/11 and activates signaling pathways important for excitatory synaptic transmission. Emerging studies reveal that Amyloid b (Ab) acts as an extracellular scaffold for mGluR5. We have identified Ca²⁺/Calmodulin-dependent protein Kinase IIα (CAMKIIα) as an interacting protein of mGluR5. We hypothesize that CaMKIIα plays a role in mGluR5 signaling and Ab produces differential effects on the regulation of mGluR5 by CAMKIIα. We find that overexpression of CAMKIIα significantly impairs mGluR5-mediated ERK1/2 phosphorylation but does not effect inositol phosphate formation or Ca²⁺ release. …

The Antisaccade Task: Visual Distractors Elicit A Location-Independent Planning 'Cost', Jesse C. Desimone

Electronic Thesis and Dissertation Repository

Prosaccades are rapid eye movements with direct stimulus and response relations and are designed to bring the fovea onto a target or area of interest. In contrast, antisaccades require the inhibition of a prosaccade and the evocation of a saccade to a target’s mirror-symmetrical location. Previous work has shown that a remote (i.e., midline, contralateral) – but not proximal (i.e., ipsilateral) – task-irrelevant distractor relative to a visual target delays prosaccade reaction times (RT) (i.e., remote distractor effect: RDE). To my knowledge, however, no work has examined whether antisaccade RTs are similarly influenced by a RDE. Accordingly, I sought to …

Task-Switching In Oculomotor Control: Systematic Investigations Of The Unidirectional Prosaccade Switch-Cost, Jeffrey Weiler

Electronic Thesis and Dissertation Repository

An antisaccade requires suppressing a stimulus-driven prosaccade (i.e., response suppression) and remapping a target’s spatial location to its mirror-symmetrical position (i.e., vector inversion). Notably, my previous work demonstrated that the successful execution of an antisaccade selectively lengthens the reaction time (RT) of a subsequently completed prosaccade (i.e., the unidirectional prosaccade switch-cost; Weiler & Heath, 2012a; Weiler & Heath, 2012b). Thus, the objective of this dissertation was further investigate, and ultimately provide a mechanistic explanation for the unidirectional prosaccade switch-cost.

In Chapter Two, I demonstrate that the magnitude of the unidirectional prosaccade switch-cost is not dependent of the number of …

Human Premotor Areas Parse Sequences Into Their Spatial And Temporal Features., Katja Kornysheva, Jörn Diedrichsen

Brain and Mind Institute Researchers' Publications

Skilled performance is characterized by precise and flexible control of movement sequences in space and time. Recent theories suggest that integrated spatio-temporal trajectories are generated by intrinsic dynamics of motor and premotor networks. This contrasts with behavioural advantages that emerge when a trained spatial or temporal feature of sequences is transferred to a new spatio-temporal combination arguing for independent neural representations of these sequence features. We used a new fMRI pattern classification approach to identify brain regions with independent vs integrated representations. A distinct regional dissociation within motor areas was revealed: whereas only the contralateral primary motor cortex exhibited unique …

A Peek Behind The Courtain: Peer Review And Editorial Decisions, Gustavo Saposnik

Gustavo Saposnik

No abstract provided.

Bdnf Maintains Adult Taste Innervation And Is Required For Taste Nerve Regeneration After Injury., Lingbin Meng

Electronic Theses and Dissertations

Brain derived neurotropic factor (BDNF) is required for the gustatory neuron survival,target innervation, and taste bud maintenance during development. However, whether BDNF has any function in the adult gustatory system in normal conditions or after nerve injury is unclear. To address these issues, I inducibly removed BDNF in all cells expressing BDNF in adult mice. In the experimental animals, Bdnf expression decreased to 5% of control mice in the lingual epithelium and geniculate ganglion (p< 0.01) at both two weeks and ten weeks after tamoxifen administration. I found no effect on taste bud morphology at four weeks following Bdnf gene deletion. However, ten weeks following Bdnf gene deletion, P2X3-positive and TUJ1-positive gustatory innervation to individual taste buds was reduced by nearly half (each with p < 0.01) and both taste bud volume and taste cell number decreased 30% (each with p< 0.01). These experiments demonstrate that BDNF is required for maintenance of normal levels of taste innervation and normal taste bud morphology in adulthood. In addition, taste cells expressing PLCß2 (phospholipase C ß2), a marker for taste cells that respond to sweet, bitter and umami, did not decrease after Bdnf gene deletion in the adult. Thus, the missing taste cells are of another type. This indicates that taste cell loss is not uniform across the various taste cell types, even if nearly all taste cell types receive the P2X3 and TUJ1 innervation. Since BDNF is required for initial innervation of the taste system and supports taste bud innervation and size in adulthood, it could also be required for nerve reinnervation after injury. To determine if Bdnf is still expressed following nerve section, the chorda tympani nerve (taste nerve) was sectioned and Bdnf level was detected with Real Time RT-PCR. Bdnf continued to be expressed at normal levels from two days to two months post-surgery in both geniculate ganglion and tongue epithelium. Therefore, BDNF could be involved with chorda tympani regeneration. To determine if this was the case, the Bdnf gene was deleted in adult inducible transgenic mice (under the control of a Ubiquitin promoter) two weeks before chorda tympani nerve section. Taste bud number was reduced by half in all genotypes at two weeks post-surgery (p < 0.01). For the remaining taste buds, gustatory innervation was nearly gone with only a little innervation from the trigeminal nerve remaining in the taste bud (p < 0.01). Taste bud volume (p < 0.01) and taste cell number (p< 0.01) were reduced by half for both control and experimental genotypes. Eight weeks post-surgery, taste bud number recovered in mice without Bdnf gene deletion, but did not recover in mice following Bdnf gene deletion (p < 0.01). Gustatory nerve innervation returned in 70% of the taste buds in control mice (p< 0.01). For those reinnervated taste buds, both taste bud volume and taste cell number increased to normal levels. However, in mice lacking the Bdnf gene, gustatory fibers only reinnervated 7.8% of the taste buds (p < 0.01); for most uninnervated taste buds, both taste bud volume and taste cell number remained small. These experiments demonstrate that BDNF is crucial for promoting regeneration of gustatory nerve fibers in adulthood. Following gustatory nerve section, considerable adult plasticity has been observed on the contralateral side including enlarged taste buds with more cells (Guagliardo and Hill, 2007). To determine if this anatomical change was associated with alter Bdnf expression. I examined Bdnf level in the geniculate ganglion and tongue epithelium on the contralateral side following chorda tympani nerve section. Results showed Bdnf expression increased two fold at two weeks post-surgery in geniculate ganglion on the contralateral side (p < 0.05), indicating BDNF may involve with the observed plastic changes. To determine if the increase in taste bud size was associated with increased innervation and/or regulated by BDNF, the Bdnf gene was then deleted in inducible knockout mice before nerve surgery, and taste bud size and amount of innervation were measured on the contralateral side. The results showed taste bud volume, taste cell number and a marker for nerve fibers all increased on the contralateral side in mice without Bdnf gene deletion at eight weeks post-surgery. This indicates that larger taste buds could be supported by increased TUJ1 positive fibers from trigeminal nerve. In addition, in mice lacking Bdnf, taste bud volume, taste cell number and innervation did not increase on the contralateral side after surgery, which indicates that Bdnf may contribute to larger taste buds on the contralateral side following nerve section by supporting increased innervation to the larger taste buds.

The Effect Of Acute Lps-Induced Immune Activation And Brain Insulin Signaling Disruption In A Diabetic Model Of Alzheimer's Disease, Andrew Scott Murtishaw

UNLV Theses, Dissertations, Professional Papers, and Capstones

Alzheimer's disease (AD) is a neurodegenerative disorder marked by progressive cognitive impairments and pathological hallmarks that include amyloid plaques, neurofibrillary tangles, and neuronal loss. Several well-known mutations exist that lead to early-onset familial AD (fAD). However, these cases only account for a small percentage of total AD cases. The vast majority of AD cases are sporadic in origin (sAD) and are less clearly influenced by a single mutation but rather some combination of genetic and environmental risk.

The etiology of sAD remains unclear but numerous risk factors have been identified that increase the chance of developing AD. Among these risk …

Self-Injurious Behaviours Are Associated With Alterations In The Somatosensory System In Children With Autism Spectrum Disorder., Emma G Duerden, Dallas Card, S Wendy Roberts, Kathleen M Mak-Fan, M Mallar Chakravarty, Jason P Lerch, Margot J Taylor

Brain and Mind Institute Researchers' Publications

Children with autism spectrum disorder (ASD) frequently engage in self-injurious behaviours, often in the absence of reporting pain. Previous research suggests that altered pain sensitivity and repeated exposure to noxious stimuli are associated with morphological changes in somatosensory and limbic cortices. Further evidence from postmortem studies with self-injurious adults has indicated alterations in the structure and organization of the temporal lobes; however, the effect of self-injurious behaviour on cortical development in children with ASD has not yet been determined. Thirty children and adolescents (mean age = 10.6 ± 2.5 years; range 7-15 years; 29 males) with a clinical diagnosis of …

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 …

Ihome: Ipad Application For Stoke Rehab At Home, Gustavo Saposnik

Gustavo Saposnik

No abstract provided.

Fty720 (Fingolimod) Provides Insight Into The Molecular Mechanisms Of Multiple Sclerosis, Madelyn Elizabeth Crawford

Pursuit - The Journal of Undergraduate Research at The University of Tennessee

Multiple sclerosis (MS) is a neurodegenerative disorder caused by a prolonged immune- mediated inflammatory response that targets myelin. Nearly all of the drugs approved for the treatment of MS are general immunosuppressants or only function in symptom management. The oral medication fingolimod, however, is reported to have direct therapeutic effects on cells of the central nervous system in addition to immunomodulatory functions. Fingolimod is known to interact with sphingosine-1-phosphate (S1P) receptors, and the most widely- accepted theory for its mechanism of action is functional antagonism of the receptor. This review examines significant neuromodulatory effects achieved by functional antagonism of the …

Overt Responses During Covert Orienting., Brian D Corneil, Douglas P Munoz

Brain and Mind Institute Researchers' Publications

A distributed network of cortical and subcortical brain areas controls our oculomotor behavior. This network includes the superior colliculus (SC), which coordinates an ancient visual grasp reflex via outputs that ramify widely within the brainstem and spinal cord, accessing saccadic and other premotor and autonomic circuits. In this Review, we discuss recent results correlating subliminal SC activity in the absence of saccades with diverse components of the visual grasp reflex, including neck and limb muscle recruitment, pupil dilation, and microsaccade propensity. Such subtle manifestations of covert orienting are accessible in the motor periphery and may provide the next generation of …

Age-Associated Increases In Fkbp51 Facilitate Tau Neurotoxicity, Laura J. Blair

USF Tampa Graduate Theses and Dissertations

Tau is a protein which regulates microtubule stability and is heavily involved in axonal transport. This stability is dynamically controlled in part by over 40 phosphorylation sites across the tau protein which allows for binding and release from the microtubules. However, if abnormal hyperphosphorylation occurs, tau dissociates from the microtubules. Once released, the microtubules become unstable and the aberrant tau mislocalizes from the axon to the somatodendric compartment, where it aggregates. These aggregates are made of many pathological forms of tau including oligomeric species, paired helical filaments, and neurofibrillary tangles, all of which have associated toxicities. Tau pathology is a …

Abcc9 Gene Polymorphism Is Associated With Hippocampal Sclerosis Of Aging Pathology, Peter T. Nelson, Steven Estus, Erin L. Abner, Ishita Parikh, Manasi Malik, Janna H. Neltner, Eseosa Ighodaro, Wang-Xia Wang, Bernard R. Wilfred, Li-San Wang, Walter A. Kukull, Kannabiran Nandakumar, Mark L. Farman, Wayne W. Poon, Maria M. Corrada, Claudia H. Kawas, David H. Cribbs, David A. Bennett, Julie A. Schneider, Eric B. Larson, Paul K. Crane, Otto Valladares, Frederick A. Schmitt, Richard J. Kryscio, Gregory A. Jicha, Charles D. Smith, Stephen W. Scheff, Joshua A. Sonnen, Jonathan L. Haines, Margaret A. Pericak-Vance, Richard Mayeux, Lindsay A. Farrer, Linda J. Van Eldik, Craig Horbinski, Robert C. Green, Marla Gearing, Leonard W. Poon, Patricia L. Kramer, Randall L. Woltjer, Thomas J. Montine, Amanda B. Partch, Alexander J. Rajic, Katierose Richmire, Sarah E. Monsell, Gerard D. Schellenberg, David W. Fardo

Pathology and Laboratory Medicine Faculty Publications

Hippocampal sclerosis of aging (HS-Aging) is a high-morbidity brain disease in the elderly but risk factors are largely unknown. We report the first genome-wide association study (GWAS) with HS-Aging pathology as an endophenotype. In collaboration with the Alzheimer's Disease Genetics Consortium, data were analyzed from large autopsy cohorts: (#1) National Alzheimer's Coordinating Center (NACC); (#2) Rush University Religious Orders Study and Memory and Aging Project; (#3) Group Health Research Institute Adult Changes in Thought study; (#4) University of California at Irvine 90+ Study; and (#5) University of Kentucky Alzheimer's Disease Center. Altogether, 363 HS-Aging cases and 2,303 controls, all pathologically …

Inhibition Of Food Intake By Pacap In The Hypothalamic Ventromedial Nuclei Is Mediated By Nmda Receptors, Jon M. Resch, Brian Maunze, Kailynn A. Phillips, Sujean Choi

Biomedical Sciences Faculty Research and Publications

Central injections of pituitary adenylate cyclase-activating polypeptide (PACAP) into the ventromedial nuclei (VMN) of the hypothalamus produce hypophagia that is dependent upon the PAC1 receptor; however, the signaling downstream of this receptor in the VMN is unknown. Though PACAP signaling has many targets, this neuropeptide has been shown to influence glutamate signaling in several brain regions through mechanisms involving NMDA receptor potentiation via activation of the Src family of protein tyrosine kinases. With this in mind, we examined the Src-NMDA receptor signaling pathway as a target for PACAP signaling in the VMN that may mediate its effects on feeding behavior. …

Humor's Effect On Short-Term Memory In Older Adults: An Innovative Wellness Paradigm, Gurinder Singh Bains

Loma Linda University Electronic Theses, Dissertations & Projects

Context: With ageing, the detrimental effects of stress can impair the ability to learn and sustain memory. Humor and the associated mirthful laughter can reduce stress by decreasing the hormone cortisol. Chronic release of cortisol can damage hippocampal neurons leading to impairment of learning and memory. Objectives: To examine the effect of watching a humor video on short term memory in older adults. Design: A randomized, controlled trial. Setting: Loma Linda University, Loma Linda, CA. Participants: 30 subjects: 20 normal healthy, older adults, 11 males and 9 females; 10 Type 2 Diabetic older adults, 6 males and 4 females. Intervention: …

Examining Dorsal Striatum In Cognitive Effort Using Parkinson's Disease And Fmri., Alex A Macdonald, Ken N Seergobin, Ruzbeh Tamjeedi, Adrian M Owen, Jean-Sebastien Provost, Oury Monchi, Hooman Ganjavi, Penny A Macdonald

Brain and Mind Institute Researchers' Publications

OBJECTIVE: Understanding cognition mediated by the striatum can clarify cognitive deficits in Parkinson's disease (PD). Previously, we claimed that dorsal striatum (DS) mediates cognitive flexibility. To refute the possibility that variation in cognitive effort confounded our observations, we reexamined our data to dissociate cognitive flexibility from effort. PD provides a model for exploring DS-mediated functions. In PD, dopamine-producing cells supplying DS are significantly degenerated. DS-mediated functions are impaired off and improved on dopamine replacement medication. Functional magnetic resonance imaging (fMRI) can confirm striatum-mediated functions.

METHODS: Twenty-two PD patients, off-on dopaminergic medication, and 22 healthy age-matched controls performed a number selection …

Octopamine Neuromodulation Regulates Gr32a-Linked Aggression And Courtship Pathways In Drosophila Males, Jonathan C. Andrews, Maria Paz Fernàndez, Qin Yu, Gregory Patrick Leary, Adelaine K. W. Leung, Michael P. Kavanaugh, Edward A. Kravitz, Sarah J. Certel

Biological Sciences Faculty Publications

Chemosensory pheromonal information regulates aggression and reproduction in many species, but how pheromonal signals are transduced to reliably produce behavior is not well understood. Here we demonstrate that the pheromonal signals detected by Gr32a-expressing chemosensory neurons to enhance male aggression are filtered through octopamine (OA, invertebrate equivalent of norepinephrine) neurons. Using behavioral assays, we find males lacking both octopamine and Gr32a gustatory receptors exhibit parallel delays in the onset of aggression and reductions in aggression. Physiological and anatomical experiments identify Gr32a to octopamine neuron synaptic and functional connections in the suboesophageal ganglion. Refining the Gr32a-expressing population indicates that mouth Gr32a …

Implications Of Human Umbilical Cord Blood Cells: An Immunotherapeutic Strategy For Alzheimer's Disease, Donna Darlington

USF Tampa Graduate Theses and Dissertations

ABSTRACT

Alzheimer's disease (AD) is the most common progressive age related dementia and the fourth major cause of mortality in the elderly in the United States. AD is pathologically characterized by deposition of amyloid beta (Aβ) plaques in the brain parenchyma and neurofibrillary tangles (NFTs) within the neuronal soma. While pharmacological targets have been discovered, current strategies for the symptomatic or disease-modifying treatment of AD do not significantly slow or halt the underlying pathological progression of the disease. Consequently, more effective treatment is needed. One possibility for amelioration is using human umbilical cord blood cell (HUCBC) therapy. HUCBCs comprise a …

Motor Axon Synapses On Renshaw Cells Contain Higher Levels Of Aspartate Than Glutamate, Dannette Shanon Richards, Ronald W. Griffith, Shannon H. Romer, Francisco J. Alvarez

Neuroscience, Cell Biology & Physiology Faculty Publications

Motoneuron synapses on spinal cord interneurons known as Renshaw cells activate nicotinic, AMPA and NMDA receptors consistent with co-release of acetylcholine and excitatory amino acids (EAA). However, whether these synapses express vesicular glutamate transporters (VGLUTs) capable of accumulating glutamate into synaptic vesicles is controversial. An alternative possibility is that these synapses release other EAAs, like aspartate, not dependent on VGLUTs. To clarify the exact EAA concentrated at motor axon synapses we performed a quantitative postembedding colloidal gold immunoelectron analysis for aspartate and glutamate on motor axon synapses (identified by immunoreactivity to the vesicular acetylcholine transporter; VAChT) contacting calbindin-immunoreactive (-IR) Renshaw …