Neuroscience and Neurobiology Commons^™

Kif11 Dependent Cell Cycle Progression In Radial Glial Cells Is Required For Proper Neurogenesis In The Zebrafish Neural Tube, Kimberly Johnson, Chelsea Moriarty, Nessy Tania, Alissa Ortman, Kristina Dipietrantonio, Brittany Edens, Jean Eisenman, Deborah Ok, Sarah Krikorian, Jessica Barragan, Christophe Golé, Michael J.F. Barresi

Mathematics Sciences: Faculty Publications

Radial glia serve as the resident neural stem cells in the embryonic vertebrate nervous system, and their proliferation must be tightly regulated to generate the correct number of neuronal and glial cell progeny in the neural tube. During a forward genetic screen, we recently identified a zebrafish mutant in the kif11 loci that displayed a significant increase in radial glial cell bodies at the ventricular zone of the spinal cord. Kif11, also known as Eg5, is a kinesin-related, plus-end directed motor protein responsible for stabilizing and separating the bipolar mitotic spindle. We show here that Gfap+ radial glial cells express …

The Effect Of Age On Neural Processing Of Pleasant Soft Touch Stimuli, April C. May, Jennifer L. Stewart, Susan F. Tapert, Martin P. Paulus

Publications and Research

Tactile interactions with our environment stimulate afferent fibers within the skin, which deliver information about sensations of pain, texture, itch and other feelings to the brain as a comprehensive sense of self. These tactile interactions can stimulate brain regions involved in interoception and reward processing. This study examined subjective, behavioral, and neural processing as a function of age during stimulation of A-beta (Aβ) and C tactile (CT) afferents using a soft brush stroke task. 16 adolescents (ages 15–17), 22 young adults (ages 20–28), and 20 mature adults (ages 29–55) underwent a simple continuous performance task while periodically anticipating and experiencing …

Attracting Female Students To Science: An Interdisciplinary Stress-Psychobiology Mentored Experience, Michael Larson

Journal of Undergraduate Research

Women have made considerable progress in education and the workplace; however, progress in science and technology fields continues to lag behind. Females remain underrepresented in science majors at the university level and, subsequently, represent less than a quarter of full professors in scientific fields. Increasing female representation in science is considered a national priority. Studies indicate women who receive a mentored scientific experience are more likely to choose careers in science and research than peers who are not exposed to scientific research in a mentored environment. Thus, our grant focused on attracting female students to the academic and scientific environment …

Dimorphic Expression Of Medial Basal Hypothalamic-Preoptic Area Calbindin-D28k Mrna During Perinatal Development In Sprague-Dawley Rats, Emily Briton, Dr. Edwin D. Lephart

Journal of Undergraduate Research

Calbindin-D28K (CALB), a calcium binding protein, is one of the most abundant proteins found in neurons of certain brain areas. It is potentially important in neuron formation and may play a protective role against programmed cell death [1]. CALB helps regulate the amount of calcium in neurons. An over-abundance of intracellular calcium leads to cell degeneration and eventually cell death. Brain sites that are exposed to toxic amounts of calcium experience less neurodegeneration where calcium-binding proteins are present than in areas where the protein is less abundant [4]. It is hypothesized that decreased levels of CALB lead to patterns of …

Investigating Habits: Strategies,Technologies And Models, Kyle S. Smith, Ann M. Graybiel

Dartmouth Scholarship

Understanding habits at a biological level requires a combination of behavioral observations and measures of ongoing neural activity. Theoretical frameworks as well as definitions of habitual behaviors emerging from classic behavioral research have been enriched by new approaches taking account of the identification of brain regions and circuits related to habitual behavior. Together, this combination of experimental and theoretical work has provided key insights into how brain circuits underlying action-learning and action-selection are organized, and how a balance between behavioral flexibility and fixity is achieved. New methods to monitor and manipulate neural activity in real time are allowing us to …

Hilar Mossy Cells Provide The First Glutamatergic Synapses To Adult-Born Dentate Granule Cells, Jessica H. Chancey, David J. Poulsen, Jacques I. Wadiche, Linda Overstreet-Wadiche

Biomedical and Pharmaceutical Sciences Faculty Publications

Adult-generated granule cells (GCs) in the dentate gyrus must establish synapses with preexisting neurons to participate in network activity. To determine the source of early glutamatergic synapses on newborn GCs in adult mice, we examined synaptic currents at the developmental stage when NMDA receptor-mediated silent synapses are first established. We show that hilar mossy cells provide initial glutamatergic synapses as well as disynaptic GABAergic input to adult-generated dentate GCs.

The Developmental Trajectory Of Contour Integration In Autism Spectrum Disorders, Ted S. Altschuler

Dissertations, Theses, and Capstone Projects

Sensory input is inherently ambiguous and complex, so perception is believed to be achieved by combining incoming sensory information with prior knowledge. One model envisions the grouping of sensory features (the local dimensions of stimuli) to be the outcome of a predictive process relying on prior experience (the global dimension of stimuli) to disambiguate possible configurations those elements could take. Contour integration, the linking of aligned but separate visual elements, is one example of perceptual grouping. Kanizsa-type illusory contour (IC) stimuli have been widely used to explore contour integration processing. Consisting of two conditions which differ only in the alignment …

Effects Of 5-Hydroxytryptamine 2c Receptor Agonist Mk212 And 2a Receptor Antagonist Mdl100907 On Maternal Behavior In Postpartum Female Rats, Weihai Chen, Qi Zhang, Wenxin Su, Yu Yang, Jing Qiao, Nan Sui, Ming Li

Department of Psychology: Faculty Publications

Maternal behavior in rats is a highly motivated and well-organized social behavior. Given the known roles of serotonin (5-HT) in emotion, motivation, social behavior, and major depression – and its known interaction with dopamine – it is likely that serotonin also plays a crucial role in this behavior. So far, there are surprisingly few studies focusing on 5-HT in maternal behavior, except for maternal aggression. In the present study,we examined the effects of 5-HT_2C receptor agonism and 5-HT_2A receptor antagonism on maternal behavior in postpartum female rats.We hypothesized that activation of 5-HT_2C receptors and blockade of 5-HT …

Supraspinal And Spinal Mechanisms Of Morphine-Induced Hyperalgesia, Caroline A. Arout

Dissertations, Theses, and Capstone Projects

Morphine is the most prominent pharmacological treatment for moderate to severe pain in both acute and chronic paradigms. However, morphine notoriously elicits a paradoxical state of increased pain sensitivity known as hyperalgesia that complicates its use in clinical application. Research over the past three decades has reported that morphine-induced hyperalgesia is dose- and sex-dependent, and likely involves the synchronous activity of several neural networks beyond the opioid system. Whereas systemic, supraspinal, and spinal administration of morphine all cause hyperalgesia that is differentially reversible by N-methyl-D-aspartate receptor (NMDAR) antagonists or melanocortin-1 receptor (MC1R) antagonists, it is unknown as to whether or …

The Neurodevelopment Of Basic Sensory Processing And Integration In Autism Spectrum Disorder, Alice Brown Brandwein

Dissertations, Theses, and Capstone Projects

This thesis presents three studies that together explore the neurophysiological basis for the sensory processing and integration abnormalities that have been observed in autism spectrum disorder (ASD) since the disorder was first described over half a century ago. In designing these studies we seek to fill a hole that currently exists in the research community‟s knowledge of the neurodevelopment of basic multisensory integration -- both in children with autism and as well as in those with typical development. The first study applied event related potentials (ERPs) and behavioral measures of multisensory integration to a large group of healthy participants ranging …

Direct Control Of Visual Perception With Phase-Specific Modulation Of Posterior Parietal Cortex, Andrew Jaegle, Tony Ro

Publications and Research

We examined the causal relationship between the phase of alpha oscillations (9–12 Hz) and conscious visual perception using rhythmic TMS (rTMS) while simultaneously recording EEG activity. rTMS of posterior parietal cortex at an alpha frequency (10 Hz), but not occipital or sham rTMS, both entrained the phase of subsequent alpha oscillatory activity and produced a phase-dependent change on subsequent visual perception, with lower discrimination accuracy for targets presented at one phase of the alpha oscillatory waveform than for targets presented at the opposite phase. By extrinsically manipulating the phase of alpha before stimulus presentation, we provide direct evidence that the …

Using Otoacoustic Emissions To Evaluate Efferent Auditory Function In Humans, Simon Henin

Dissertations, Theses, and Capstone Projects

The auditory system continually adapts to changes in the acoustic environment over short periods of time. This fine-tuning of its dynamics is mediated in part by the medial olivocochlear (MOC) bundle, a neural feedback loop which aids in the regulation of cochlear micro-mechanics. The ability to measure the response of the MOC system in humans may provide significant insight into unique cochlear functions, such as its sharp frequency selectivity and wide dynamic range. In humans the efferent system can be investigated non-invasively using otoacoustic emissions (OAEs). However, how OAEs can best be used to evaluate efferent function, the pitfalls associated …

The Interplay Of Visual Attention And Saccade Planning In Active Vision, Afsheen Khan

Dissertations, Theses, and Capstone Projects

Vision is a highly active process. When we view the world, we do not hold our eyes still, but constantly move them around in order to view the object or area of interest with the fovea (the region of the retina with the highest acuity). Saccades are the step-like movements that we most often employ for this purpose. In addition, our attention is constantly being covertly attracted or directed to points of interest. Combining these different aspects of viewing: visual processing, the orienting of attention, and eye movements can be referred to as `active vision'.

Most work on active vision …

Vegf Treatment During Status Epilepticus Alters Long-Term Hippocampal Astrocyte Morphology: A Detailed Description Of Astrocyte Morphology And Glutamate Transporter Patterns With And Without Administration Of Vegf And Seizure Induction, Janice Rene Lenzer

Dissertations, Theses, and Capstone Projects

VEGF treatment during pilocarpine-induced status epilepticus (SE) causes enduring preservation of behavioral function in rats in the absence of enduring neuroprotection (Nicoletti et al., 2010). In addition, VEGF treatment reduces hyperexcitability in hippocampal slices without altering neuronal membrane properties (McCloskey et al, 2005). Combined, these data suggest the possibility that other cells or mechanisms could be involved in the beneficial effects of VEGF during SE. Our laboratory is interested in the potential contribution of astrocytes to these effects. Astrocytes are not only reported to contribute to epileptiform discharges in the hippocampus (Tian et al., 2005; Kang et al., 2005) but …

The Characterization Of Pb2+ Toxicity In Rat Neural Development: An Assessment Of Pb2+ Effects On The Gaba Shift In Neural Networks And Implications For Learning And Memory Disruption, Lorenz Simon Neuwirth

Dissertations, Theses, and Capstone Projects

The toxic effects of Pb2+ on the developing rat nervous system has been investigated to assess early developmental GABAergic disruption and its implications with altering inhibitory learning and memory. This goal was achieved using a multi-systems approach: blood lead levels (clinical physiology), qRT-PCR (molecular genetics), brain and primary neuronal culture immunology (immunohistochemical and cellular approaches), physiological cellular components (synaptosomes and protein expression) and finally through learning and memory assessment with GABA mimetic drug manipulations in the intact animal (behavioral pharmacology). The influence of a 956ppm Pb2+ gestational diet (i.e. from birth to sacrifice) resulted in pup mean blood lead levels …

Intracellular Mechanisms Associated With Cocaine Induced Conditioned Place Preference, Stephanie K. Nygard

Dissertations, Theses, and Capstone Projects

The aim of this dissertation was to investigate the intracellular responses associated with the acquisition and expression of cocaine-context associations. ERK (extracellular regulated kinase), CREB (cAMP responsive element binding protein), FosB and deltaFosB proteins were of particular interest due to their involvement in cocaine reward and in synaptic plasticity underlying learning and memory. We used the conditioned place preference (CPP) paradigm, which employs a Pavlovian conditioning procedure to establish an association between a drug-paired environment and the drug's rewarding effects, to study the role of these signaling pathways in cocaine-context associations. N-methyl-D-aspartate receptor (NMDAR) antagonism prior to cocaine administration during …

On The Role Of Neuronal Oscillations In Auditory Cortical Processing, Monica Noelle O'Connell

Dissertations, Theses, and Capstone Projects

Although it has been over 100 years since William James stated that "everyone knows what attention is", its underlying neural mechanisms are still being debated today. The goal of this research was to describe the physiological mechanisms of auditory attention using direct electrophysiological recordings in macaque primary auditory cortex (A1). A major focus of my research was on the role ongoing neuronal oscillations play in attentional modulation of auditory responses in A1.

For all studies, laminar profiles of synaptic activity, (indexed by current source density analysis) and concomitant firing patterns in local neurons (multiunit activity) were acquired simultaneously via linear …

Neurophysiological Bases Of Frequency Discrimination In Children With Auditory Processing Disorder Or Specific Language Impairment, Christine Rota-Donahue

Dissertations, Theses, and Capstone Projects

The purpose of this study was to determine if 10-12 year old children with Auditory Processing Disorder (APD) or Specific Language Impairment (SLI) could discriminate three different frequency changes behaviorally and electrophysiologically. Behavioral frequency discrimination and event-related potentials were examined using a 1000Hz pure tone base frequency. Typically developing children and children with APD or SLI differed in in their detection of frequency changes: behavioral results were below chance level and the MMN amplitude was smaller in the impaired population. Slight differences between children with APD and children with SLI were also found that might shed light on the controversy …

Neuroimmune Crosstalk: A Role For Neuropeptide Y In Inflammatory Bowel Disease, Henry H. Ruiz

Dissertations, Theses, and Capstone Projects

Neuropeptide Y (NPY) is a 36-amino acid peptide widely expressed in the central and peripheral nervous systems. In addition to other cells, NPY is also synthesized and co-released from sympathetic nerve fibers functioning as a potent sympathetic neuromodulator. NPY has been implicated in playing important roles in the regulation of energy balance, appetite, anxiety, vascular tone, and immune cell functioning. In addition, immune cells of both the innate and adaptive immune systems express functional NPY receptors. Some immune cells can produce and secrete NPY, and genetic alteration of these receptors results in altered immune cell functioning. Its direct association with …

Quantitative Evaluation Of Microglial Activation And Vascularization In Suicide, Tatiana Pavlovna Schnieder

Dissertations, Theses, and Capstone Projects

Accumulated evidence points to immunological factors in psychiatric disorders. In a variety of chronic neurological disorders, exacerbation is associated with inflammation and a loss of integrity of the blood-brain barrier. Microglia, the principal brain immunological cells in the healthy state, respond to changes in the internal environment of the brain through a sequence of activated states. This study compared microglial phenotypes in the white matter of autopsy brains from 11 suicide victims and 25 subjects who died involuntarily. Both groups included cases with and without major psychiatric disorders, which were determined by PA interviews. Cases were matched for sex, age, …