Neuroscience and Neurobiology Commons^™

Homo Naledi, A New Species Of The Genus Homo From The Dinaledi Chamber, South Africa, Lee R. Berger, John Hawks, Darryl J. De Ruiter, Steven E. Churchill, Peter Schmid, Lucas K. Delezene, Tracy L. Kivell, Heather M. Garvin, Scott A. Williams, Jeremy M. Desilva, Matthew M. Skinner, Charles M. Musiba, Noel Cameron, Trenton W. Holliday, William Harcourt-Smith, Rebecca R. Ackermann, Markus Bastir, Barry Bogin, Debra Bolter, Juliet Brophy, Zachary D. Cofran, Kimberly A. Congdon, Andrew S. Deane, Mana Dembo, Michelle Drapeau, Marina C. Elliott, Elen M. Feuerriegel, Daniel Garcia-Martinez, David J. Green, Alia Gurtov, Joel D. Irish, Ashley Kruger, Myra F. Laird, Damiano Marchi, Marc R. Meyer, Shahed Nalla, Enquye W. Negash, Caley M. Orr, Davorka Radovcic, Lauren Schroeder, Jill E. Scott, Zachary Throckmorton, Matthew W. Tocheri, Caroline Vansickle, Christopher S. Walker, Pianpian Wei, Bernhard Zipfel

Neuroscience Faculty Publications

Homo naledi is a previously-unknown species of extinct hominin discovered within the Dinaledi Chamber of the Rising Star cave system, Cradle of Humankind, South Africa. This species is characterized by body mass and stature similar to small-bodied human populations but a small endocranial volume similar to australopiths. Cranial morphology of H. naledi is unique, but most similar to early Homo species including Homo erectus, Homo habilis or Homo rudolfensis. While primitive, the dentition is generally small and simple in occlusal morphology. H. naledi has humanlike manipulatory adaptations of the hand and wrist. It also exhibits a humanlike foot …

Neurobiology Of Seasonal Life-History Transitions, Ashley Rae Lucas

Dissertations and Theses

Many animals exhibit seasonal changes in life-history stages, and these seasonal transitions are often accompanied by dramatic switches in behavior. While the neuroendocrine mechanisms that regulate such behavioral transitions are poorly understood, arginine vasotocin (AVT) and neuropeptide Y (NPY) are excellent candidates because they regulate reproductive and feeding behavior, respectively. In this study, I asked if seasonal changes in AVT and/or NPY are concomitant with spring migration away from the breeding grounds, as male and female red-sided garter snakes (Thamnophis sirtalis parietalis) are transitioning from reproductive to non-reproductive behavior during this time. To address this question, I collected …

Effects Of Testosterone On The Spatial Ecology, Coloration, And Brain Regions In Western Fence Lizards, Sceloporus Occidentalis, Rachel Catharine Wilson

Master's Theses

An organism’s spatial ecology allows for access to essential resources such as food, mates, and escape from predators. Home range size, or the total area an organism inhabits, varies in relation to numerous factors including seasonality. During the breeding season, home range size increases in males across taxa. In addition, males usually also have larger home range sizes than females. This implicates testosterone (T) as a possible mediator of this relationship. Indeed, T causes an increase in home range size of males in numerous species of lizards. In addition to T causing an increase in home range size, it also …

Familiar Face Detection In 180ms, Matteo Visconti Di Oleggio Castello, M. Ida Gobbini

Dartmouth Scholarship

The visual system is tuned for rapid detection of faces, with the fastest choice saccade to a face at 100ms. Familiar faces have a more robust representation than do unfamiliar faces, and are detected faster in the absence of awareness and with reduced attentional resources. Faces of family and close friends become familiar over a protracted period involving learning the unique visual appearance, including a view-invariant representation, as well as person knowledge. We investigated the effect of personal familiarity on the earliest stages of face processing by using a saccadic-choice task to measure how fast familiar face detection can happen. …

Short-Term Memory For Space And Time Flexibly Recruit Complementary Sensory-Biased Frontal Lobe Attention Networks, Samantha W. Michalka, Lingqiang Kong, Maya L. Rosen, Barbara G. Shinn-Cunningham, David C. Somers

Neuroscience: Faculty Publications

The frontal lobes control wide-ranging cognitive functions; however, functional subdivisions of human frontal cortex are only coarsely mapped. Here, functional magnetic resonance imaging reveals two distinct visual-biased attention regions in lateral frontal cortex, superior precentral sulcus (sPCS) and inferior precentral sulcus (iPCS), anatomically interdigitated with two auditory-biased attention regions, transverse gyrus intersecting precentral sulcus (tgPCS) and caudal inferior frontal sulcus (cIFS). Intrinsic functional connectivity analysis demonstrates that sPCS and iPCS fall within a broad visual-attention network, while tgPCS and cIFS fall within a broad auditory-attention network. Interestingly, we observe that spatial and temporal short-term memory (STM), respectively, recruit visual and …

Characteristics Of Exocytosis And Endocytosis In Photoreceptors, Karlene M. Cork

Theses & Dissertations

Photoreceptors signal changes in light intensity to downstream retinal neurons through the exocytosis of glutamate-containing synaptic vesicles. The maintenance of the vesicle exocytosis and endocytosis process is essential for ongoing synaptic signaling. This study investigated the properties of exocytosis and endocytosis in photoreceptors and their role in ongoing neurotransmission.

I used electrophysiology and imaging techniques to study the properties of vesicle exocytosis and endocytosis in photoreceptors. First, we examined baseline release in photoreceptors that occurs in the absence of depolarizing stimulation. We measured mEPSCs in whole cell patch clamp recordings from horizontal cells. After inhibiting Ca²⁺ influx and efflux …

Effects Of Maternal Immune Activation And Repeated Maternal Separation On Postpartum Behaviors In The Female Rat Offspring, Shinnyi Chou

Theses & Dissertations

Early life stress can induce persistent brain and behavioral alterations. As a lifetime history of clinical symptoms similar to those caused by early adversities may predict postpartum dysfunctions, these stressors likely contribute to their etiology. Postpartum neuropsychiatric disorders (e.g. postpartum depression, anxiety and depression) are costly, yet due to the complex neuronal reorganization during this period, insights into how early adversities-induced CNS functional changes affect postpartum processes remain limited, especially under multiple stressors. Thus, there is a need to determine postpartum functions altered by early stress, in order to increase understandings of risks associated with postpartum maladaptations. Accordingly, this work …

Influences Of Long-Term Memory-Guided Attention And Stimulus-Guided Attention On Visuospatial Representations Within Human Intraparietal Sulcus, Maya L. Rosen, Chantal E. Stern, Samantha W. Michalka, Kathryn J. Devaney, David C. Somers

Neuroscience: Faculty Publications

Human parietal cortex plays a central role in encoding visuospatial information and multiple visual maps exist within the intraparietalsulcus (IPS), with each hemisphere symmetrically representing contralateral visual space. Two forms of hemispheric asymmetries havebeen identified in parietal cortex ventrolateral to visuotopic IPS. Key attentional processes are localized to right lateral parietal cortex inthe temporoparietal junction and long-term memory (LTM) retrieval processes are localized to the left lateral parietal cortex in theangular gyrus. Here, using fMRI, we investigate how spatial representations of visuotopic IPS are influenced by stimulus-guided visuospatialattention and by LTM-guided visuospatial attention. We replicate prior findings that a hemispheric …

Duration Estimates Within A Modality Are Integrated Sub-Optimally, Ming Bo Cai, David M. Eagleman

Faculty, Staff and Students Publications

Perceived duration can be influenced by various properties of sensory stimuli. For example, visual stimuli of higher temporal frequency are perceived to last longer than those of lower temporal frequency. How does the brain form a representation of duration when each of two simultaneously presented stimuli influences perceived duration in different way? To answer this question, we investigated the perceived duration of a pair of dynamic visual stimuli of different temporal frequencies in comparison to that of a single visual stimulus of either low or high temporal frequency. We found that the duration representation of simultaneously occurring visual stimuli is …

A Screen To Identify Saga-Activated Genes That Are Required For Proper Photoreceptor Axon Targeting In Drosophila Melanogaster, Kaelan J. Brennan, Vikki M. Weake, Jingqun Q. Ma

The Summer Undergraduate Research Fellowship (SURF) Symposium

The inherited human genetic disease spinocerebellar ataxia type 7 (SCA7) is characterized by progressive neurodegeneration and visual impairment that ultimately leads to blindness. SCA7 results from a mutation in the human ATXN7 gene that causes an expansion of polyglutamine tracts in this gene’s corresponding protein. Human ATXN7 protein serves as a component of the deubiquitylase (DUB) module of the large, multi-subunit complex Spt-Ada-Gcn acetyltransferase, or SAGA. SAGA is a transcriptional coactivator and histone modifier that functions to deubiquitylate histone H2B and allow for transcription of SAGA-mediated genes to occur. In Drosophila, mutations in SAGA DUB’s Nonstop and sgf11 components …

Analysis Of Mitochondrial Turnover In Neuromuscular Junctions Of Parkin Mutants, Kenny Nguyen, Hyun Sung, Peter J. Hollenbeck

The Summer Undergraduate Research Fellowship (SURF) Symposium

The accumulation of dysfunctional or damaged mitochondria in neurons has been linked to the pathogenesis of many neurodegenerative diseases, such as Parkinson’s disease. It has been proposed that proteins PINK1 and Parkin regulate mitochondrial quality control by selectively targeting depolarized mitochondria for autophagic degradation, a process known as mitophagy. Though previously analyzed in the cell bodies and axons of neurons, the role of the PINK1/Parkin pathway in the synapse is unclear, and it is not known whether mitochondrial turnover occurs in the neuromuscular junctions (NMJs). To study this, intact Drosophila nervous systems were analyzed in vivo by performing gentle dissections …

Competitive Tuning Of Calmodulin Target Protein Activation Drives E-Ltp Induction In Ca1 Hippocampal Neurons, Daniel R. Romano, Tamara L. Kinzer-Ursem

The Summer Undergraduate Research Fellowship (SURF) Symposium

A number of neurological disorders are caused by disruptions in dynamic neuronal connections called synapses. Normally, electrical activity between neurons activates protein cascades that cause long-lasting, localized changes in the structure and molecular composition of synapses. These changes either increase or decrease the strength of synaptic connections, leading to long-term-potentiation (LTP) or long-term-depression (LTD), respectively. The protein cascades responsible for this synaptic plasticity are initiated in a stimulus-dependent manner by the Ca²⁺ sensor calmodulin (CaM). Ultimately, it is disruptions within these signaling pathways that cause disease. Traditionally, these protein networks are studied in the laboratory, but limitations in existing …

Behavioral Outputs Of Fragile-X Autistic Mice Exposed To Open-Field, Randomized, Short-Term Visual Stimuli, Nicholas M. Dicola, Alexander A. Chubykin

The Summer Undergraduate Research Fellowship (SURF) Symposium

Animal models of different neurological disorders are required for studying the pathophysiology of these diseases, and for potential development of pharmacological and behavioral treatments. The scientific community often uses mouse models for behavior studies due to their powerful genetic tools and low cost. However, subjective measurement techniques are often used when analyzing mice for behavioral traits which often results in discrepancies in results. An automated tracking software would aim to eliminate these discrepancies and subjective analysis. This lab has developed a software program which offered an ability to automatically collect open-field behavioral data with simultaneous on-line analysis. Python, an open …

Hippocalcin Response To Calcium: Do Conserved Tryptophans – W30 Or W103 – Matter?, Sunkesula K. Sagar

Graduate School of Biomedical Sciences Theses and Dissertations

Changes in intracellular calcium levels play a very important role in cell signaling, in turn, affecting neuronal functions such as memory, learning and cell death. A class of proteins called Neuronal Calcium Sensor (NCS) proteins serves to modulate the functioning of the neuronal cells in response to changes in calcium levels, and prevent neuronal apoptosis. Structurally, all NCS proteins have 4 calcium-binding EF hand motifs, although EF1 does not bind to calcium in many members. All NCS proteins have an acyl modification at the N- terminus – where a myristoyl group is added post-translationally. Hippocalcin (HPCA) is an NCS protein, …

Responses Of Primate Frontal Cortex Neurons During Natural Vocal Communication, Cory T. Miller, A. Wren Thomas, Samuel U. Nummela, Lisa A. De La Mothe

Psychological Sciences and Counseling Faculty Research

The role of primate frontal cortex in vocal communication and its significance in language evolution have a controversial history. While evidence indicates that vocalization processing occurs in ventrolateral prefrontal cortex neurons, vocal-motor activity has been conjectured to be primarily subcortical and suggestive of a distinctly different neural architecture from humans. Direct evidence of neural activity during natural vocal communication is limited, as previous studies were performed in chair-restrained animals. Here we recorded the activity of single neurons across multiple regions of prefrontal and premotor cortex while freely moving marmosets engaged in a natural vocal behavior known as antiphonal calling. Our …

Canonical Bmp Signaling Is Required For Allodynia In Drosophila Melanogaster, Taylor L. Follansbee

All Theses And Dissertations

In the United States alone over 100 million people suffer from chronic pain and unfortunately, even still, there is a lack in scientific understanding for the mechanisms of abnormal pain sensitivity. The present study utilized a candidate gene approach to identify novel components required for modulation of the tissue damage induced pain sensitization pathway in Drosophila melanogaster. We have shown that RNAi silencing of decapentaplegic (dpp), a member of the Bone Morphogenetic Protein (BMP) signaling pathway, specifically in the class IV multidendritic nociceptor neurons significantly attenuated UV-induced nociceptive sensitization. Furthermore, overexpression of dpp in nociceptor neurons was sufficient to …

An Analysis Of The Interaction Of Methylphenidate And Nicotine In Adolescent Rats: Effects On Bdnf, Elizabeth D. Freeman

Electronic Theses and Dissertations

This investigation was an analysis of the interaction of adolescent exposure to methylphenidate (MPH; trade name: Ritalin) on nicotine sensitization and conditioned place preference (CPP) in a rodent model and underlying mechanisms of this effect. Animals were treated IP with 1 mg/kg MPH or saline using a ―school day‖ regimen of five days on, two days off, from postnatal day (P) 28-50. During the final two weeks of MPH treatment, animals were either behaviorally sensitized to nicotine (0.5 mg/kg free base) or saline for 10 days, or conditioned to nicotine or saline using the CPP behavioral paradigm. In addition, three …

The Effect Of Sleep On Perceptual Learning And Memory Consolidation, Vanessa Claire Irsik

UNLV Theses, Dissertations, Professional Papers, and Capstones

An ability to segregate speech accurately is essential given that most auditory environments contain other overlapping conversations or environmental noise. While perceiving speech among background noise can be difficult in and of itself, those with hearing impairments can experience considerable difficulty. While training has been shown to benefit perceptual segregation of trained sounds, it is unclear how such training transfers to sounds not included in a training regimen. The current study aimed to address this question by training listeners on a portion of sounds during a vowel segregation task, and subsequently testing on both the trained sounds and untrained sounds. …

Structure And Composition Of Postsynaptic Densities, Madeline Farley

Dissertations and Theses (Open Access)

Communication between neurons within the brain occurs at chemical synapses and is fundamental for all brain functions. Modulation of the strength of communication is controlled by both presynaptic and postsynaptic mechanisms and is termed synaptic plasticity. One postsynaptic structure postulated to regulate synaptic strength is the postsynaptic density (PSD), a large electron dense protein complex located just below the synaptic membrane. The PSD, which is composed of signaling, scaffold and cytoskeletal proteins, supports and organizes neurotransmitter receptors within the synaptic membrane in addition to bridging signaling with the actin cytoskeletal network. The protein composition and structure of PSDs is known …

Concussion Awareness And Educational Outreach Through A Website And Mobile Application, Daniel J. Brogan

Neuroscience Summer Fellows

In recent years concussions have become a more apparent problem in youth and adolescent sports. 1 in 5 high school students will sustain a concussion during the season. Due to medical and scientific advances, the diagnosis of concussions is becoming much simpler with key markers that are signs for an injury. Returning to play too soon before an athlete is fully recovered increases the likelihood that serious and irreversible neurological deficits can occur. Symptoms for concussions are necessary to track in order for an athlete to properly report their recovery to a physician. Doctors primarily rely on a patient’s report …

Impaired Executive Function In Concussed Athletes, Marisa Gretz

Neuroscience Summer Fellows

Concussions are classified as mild traumatic brain injuries (mTBI). An individual that has sustained a concussion will experience symptoms such as nausea, possible memory loss, blurry vision, or loss of balance. Most symptoms subside within a few days, but a large pool of research raises concern for the recovery of executive function, specifically impulse control. Executive function relates to all tasks that require deliberate attention. Past research has shown adolescents record the highest number of sports concussions when compared to collegiate and professional athletes. The frontal lobe, which controls executive function, is not fully developed during the time of adolescence. …

The Effects Of Visual Search Efficiency On Object-Based Attention, Adam S. Greenberg, Maya Rosen, Elizabeth Cutrone, Marlene Behrmann

Neuroscience: Faculty Publications

The attentional prioritization hypothesis of object-based attention (Shomstein & Yantis in Perception & Psychophysics, 64, 41–51, 2002) suggests a two-stage selection process comprising an automatic spatial gradient and flexible strategic (prioritization) selection. The combined attentional priorities of these two stages of object-based selection determine the order in which participants will search the display for the presence of a target. The strategic process has often been likened to a prioritized visual search. By modifying the double-rectangle cueing paradigm (Egly, Driver, & Rafal in Journal of Experimental Psychology: General, 123, 161–177, 1994) and placing it in the context of a larger-scale visual …

Increased Resting-State Functional Connectivity Of Visual- And Cognitive-Control Brain Networks After Training In Children With Reading Difficulties, Tzipi Horowitz-Kraus, Mark Difrancesco, Benjamin Kay, Yingying Wang, Scott K. Holland

Center for Brain, Biology, and Behavior: Faculty Publications

The Reading Acceleration Program, a computerized reading-training program, increases activation in neural circuits related to reading.We examined the effect of the training on the functional connectivity between independent components related to visual processing, executive functions, attention, memory, and language during rest after the training. Children 8–12 years old with reading difficulties and typical readers participated in the study. Behavioral testing and functional magnetic resonance imaging were performed before and after the training. Imaging data were analyzed using an independent component analysis approach. After training, both reading groups showed increased single-word contextual reading and reading comprehension scores. Greater positive correlations between …

The Mouse That Trolled: The Long And Tortuous History Of A Gene Mutation Patent That Became An Expensive Impediment To Alzheimer's Research, Tania M. Bubela, Saurabh Vishnubhakat, Robert Cook-Deegan

Office of the Provost

This case study presents the tale of the academic discovery of a rare mutation for early-onset Alzheimer's disease that was patented by a sole inventor and licensed to a non-practicing entity (NPE), the Alzheimer's Institute of America (AIA). Our aims are (1) to relate this story about patents, research tools, and impediments to medical progress, and (2) to inform ongoing debates about how patents affect research, disposition of university inventions, and the distribution of benefits from publicly funded research. We present an account of the hunt for Alzheimer's genes, their patenting, assignment, and enforcement based on literature, litigation records and …

Erin: A Portal To Resources For Higher Education In Neuroscience, Richard F. Olivo, Joseph R. Burdo, Robert Calin-Jagemen, William Grisham, Monica L. Linden, Robert L. Rosenberg, Laura L. Symonds, Janice E. Thornton

Neuroscience: Faculty Publications

ERIN, Educational Resources in Neuroscience, is the Society for Neuroscience's web portal to selected, high- quality materials for higher education. A Board of Editors approves resources after describing them and classifying them by topic, subtopic, media type, author, and appropriate educational level. Some resources are also accompanied by reviews and ratings from faculty who have used the resource. These features make a search of ERIN far more useful than a typical Google search.

ERIN's development was funded by the National Science Foundation with a three-year grant to SfN. Along the way, various unexpected problems arose and solutions were found, many …

Subject Assessment Of In-Vehicle Auditory Warnings For Rail Grade Crossings, Steven Landry, Jayde Croschere, Myounghoon Jeon

Michigan Tech Publications, Part 1

Human factors research has played an important role in reducing the incidents of vehicle-train collisions at rail grade crossings over the past 30 years. With the growing popularity of in-vehicle infotainment systems and GPS devices, new opportunities arise to cost-efficiently and effectively alert drivers of railroad crossings and to promote safer driving habits. To best utilize this in-vehicle technology, 32 auditory warnings (16 verbal, 7 train-related auditory icons, and 9 generic earcons) were generated and presented to 31 participants after a brief low-fidelity driving simulation. Participants rated each sound on eight dimensions deemed important in previous auditory warning literature. Preliminary …

Susceptibility Of Parkinson’S Disease Following Mild Blast Traumatic Brain Injury, Glen Howel Galicia Acosta

Open Access Theses

Blast injury-induced neurotrauma (BINT) is steadily increasing in prevalence due to escalated terror activity and constitutes the signature injury associated with current military conflicts. BINT produces significant neurological deficiencies and there is a growing concern that the injury may produce long-term consequences that affect the resilience and the performance of soldiers. One of the potential consequences is an increased susceptibility to Parkinson's disease (PD). A vital goal aimed at curtailing the post-deployment long-term consequences of blast injury-induced neurotrauma is to further our knowledge of pathogenic mechanisms responsible for the escalation of post injury diseases. The purpose of this project is …

Spatiotemporal Fluctuations Of Olfactory Stimuli And Its Detection By An Optical Method, Mitu Chandra Acharjee

Graduate Theses and Dissertations

Olfactory processing in the mammalian brain is a highly dynamic process, yet most of the olfaction experiments have been studied primarily with static stimuli. Odors in the natural environment are transported by turbulent flow of air or water. Natural odorants have fluctuations in concentration and it changes rapidly with time. These rapid fluctuations may pose some challenges to identifying an odor; on the other hand, the variation itself may provide important clues about the odor source. The goal of this thesis project was to create a similar odorant environment like the rapid odor fluctuations encountered in nature – to meet …

Neonatal Isolation Stress Inhibits Pre-Weaning Weight Gain And Mild-Stressor Induced Locomotor Activity In Early Adolescent Male And Female Rats, Peter Villavecchia, Mindy Miserendino

Psychology Faculty Publications

The present study looked at the effects of neonatal isolation, an early life stress experience, in male and female early adolescent rats, an age which is underrepresented in the early stress literature. Four stress-sensitive indices were assessed: weight gain during the pre-weaning period, open field activity, and locomotor activity in response to two mild stressors: exposure to a novel environment, and a single IP saline injection. Rats in the neonatal isolation condition were removed from dam and littermates on postnatal days 2-9 in accord with the procedure used by Kehoe et al. (1995); behavioral testing occurred on PN25-PN30 during …

Onset Time And Durability Of Huntingtin Suppression In Rhesus Putamen After Direct Infusion Of Antihuntingtin Sirna, Richard Grondin, Pei Ge, Qingmin Chen, Jessica E. Sutherland, Zhiming Zhang, Don M. Gash, David K. Stiles, Gregory R. Stewart, Dinah W. Y. Sah, William F. Kaemmerer

Neuroscience Faculty Publications

One possible treatment for Huntington's disease involves direct infusion of a small, interfering RNA (siRNA) designed to reduce huntingtin expression into brain tissue from a chronically implanted programmable pump. Here, we studied the suppression of huntingtin mRNA achievable with short infusion times, and investigated how long suppression may persist after infusion ceases. Rhesus monkeys received 3 days of infusion of Magnevist into the putamen to confirm catheter patency and fluid distribution. After a 1-week washout period, monkeys received radiolabeled siRNA targeting huntingtin. After 1 or 3 days of siRNA delivery, monkeys were either terminated, or their pumps were shut off …