Physiology Commons^™

An Unattended Mask Makes An Attended Target Disappear, Arielle A. Veenemans, Patrick Cavanagh

Dartmouth Scholarship

In pattern masking, the target and mask are presented at the same location and follow one another very closely in time. When the observer attends to the target, he or she must also attend to the mask, as the switching time for attention is quite slow. In a series of experiments, we present mask–target–mask sequences staggered in time and location (Cavanagh, Holcombe, & Chou, 2008) that allow participants to attentively track the target location without attending to the masks. The results show that the strength of masking is on average unaffected by the removal of attention from the masks. Moreover, …

Rfx Transcription Factors Are Essential For Hearing In Mice, Ran Elkon, Beatrice Milon, Laura Morrison, Manan Shah, Sarath Vijayakumar, Manoj Racherla, Carmen C. Leitch, Lorna Silipino, Shadan Hadi, Michèle Weiss-Gayet, Emmanuèle Barras, Christoph D. Schmid, Aouatef Ait-Lounis, Ashley Barnes, Yang Song, David J. Eisenman, Efrat Eliyahu, Gregory I. Frolenkov, Scott E. Strome, Bénédicte Durand, Norann A. Zaghloul, Sherri M. Jones, Walter Reith, Ronna Hertzano

Physiology Faculty Publications

Sensorineural hearing loss is a common and currently irreversible disorder, because mammalian hair cells (HCs) do not regenerate and current stem cell and gene delivery protocols result only in immature HC-like cells. Importantly, although the transcriptional regulators of embryonic HC development have been described, little is known about the postnatal regulators of maturating HCs. Here we apply a cell type-specific functional genomic analysis to the transcriptomes of auditory and vestibular sensory epithelia from early postnatal mice. We identify RFX transcription factors as essential and evolutionarily conserved regulators of the HC-specific transcriptomes, and detect Rfx1,2,3,5 and 7 in the developing HCs. …

Topological Data Analysis For Discovery In Preclinical Spinal Cord Injury And Traumatic Brain Injury, Jessica L. Nielson, Jesse Paquette, Aiwen W. Liu, Cristian F. Guandique, C. Amy Tovar, Tomoo Inoue, Karen-Amanda Irvine, John C. Gensel, Jennifer Kloke, Tanya C. Petrossian, Pek Y. Lum, Gunnar E. Carlsson, Geoffrey T. Manley, Wise Young, Michael S. Beattie, Jacqueline C. Bresnahan, Adam R. Ferguson

Physiology Faculty Publications

Data-driven discovery in complex neurological disorders has potential to extract meaningful syndromic knowledge from large, heterogeneous data sets to enhance potential for precision medicine. Here we describe the application of topological data analysis (TDA) for data-driven discovery in preclinical traumatic brain injury (TBI) and spinal cord injury (SCI) data sets mined from the Visualized Syndromic Information and Outcomes for Neurotrauma-SCI (VISION-SCI) repository. Through direct visualization of inter-related histopathological, functional and health outcomes, TDA detected novel patterns across the syndromic network, uncovering interactions between SCI and co-occurring TBI, as well as detrimental drug effects in unpublished multicentre preclinical drug trial data …

Prediction Of Maximal Oxygen Consumption From Rating Of Perceived Exertion (Rpe) Using A Modified Total-Body Recumbent Stepper, John P. Mcculloch, Douglas J. Lorenz, Michael A. Kloby, Matthew D. Love, Daniela G.L. Terson De Paleville Phd

International Journal of Exercise Science

International Journal of Exercise Science 8(4): 414-424, 2015. Exercise training is crucial to improve cardiovascular health and quality of life in people with spinal cord injuries (SCI). A key limitation is the lack of validated submaximal tests to evaluate and predict cardiovascular fitness in this population. The purpose of this study was to validate a submaximal test to predict maximal oxygen consumption for individuals with SCI. Ten able-bodied participants and two individuals with SCI completed a rating of perceived exertion (RPE)-based submaximal oxygen consumption test and a graded maximal oxygen consumption test on a NuStep T4 recumbent stepper. Prediction of …

Assessment Of Dietary Behaviors, Body Composition, And Cardiovascular Disease Risk Among College Club Rugby Team, Carly R. Macdougall, Gytis Balilionis, Svetlana Nepocatych

International Journal of Exercise Science

International Journal of Exercise Science 8(4): 403-413, 2015. The purpose of this study was to evaluate dietary behaviors, body composition, and potential cardiovascular disease (CVD) risk factors among college club rugby team players. 15 athletes completed demographics, three 24-hour dietary recalls, body composition and blood lipid profile assessments following an overnight fast. Mean ± SD age of participants was 20 ± 1 years; weight 81 ± 16 kg; BMI 25.7 ± 3.2 kg/m²; body fat 13 ± 5%; total cholesterol 133 ± 37 mg/dl; high-density lipoprotein 49 ± 18 mg/dl; low-density lipoproteins 77 ± 26 mg/dl; triglycerides 86 …

The Influence Of Short-Term Quercetin Supplementation On Peak Oxygen Uptake During Simulated Altitude Exposure In Trained Cyclists, Justin A. Carlstrom

International Journal of Exercise Science

International Journal of Exercise Science 8(4): 394-402, 2015. Endurance performance and peak oxygen uptake (VO_2peak) decline as altitude increases. Some data exist suggesting that quercetin supplementation improves aerobic capacity in trained and untrained individuals at sea-level (normobaric normoxic conditions). Few studies have examined the effects of quercetin on endurance performance during simulated altitude exposure (normobaric hypoxic conditions). The purpose of this study was to determine the effects of consuming 1000 mg·day^-1 of quercetin for two weeks on cycling VO_2peak in healthy trained male cyclists performing under normobaric normoxic and hypoxic conditions (NP and HP, respectively). Fourteen …

Efficacy Of Vibration Exercise As A Warm-Up Modality For Overground Sprinting, Victoria Moddie, Amanda C. Benson, Brett A. Gordon, Noel Lythgo

International Journal of Exercise Science

International Journal of Exercise Science 8(4): 385-393, 2015. This study investigated the efficacy of vibration exercise (VbX) as a warm-up modality for maximal overground sprinting. Ten national level sprinters participated in a randomized crossover design (14.0 ± 7.4 days washout period). A VbX warm-up was compared to a warm-up involving sprint-specific exercises (control condition). The VbX warm-up involved 10 ´ 1 minute bouts delivered by a Galileo 900 side-alternating plate (frequency = 26 Hz, peak-to-peak displacement = 9 mm) with 30 s rest between bouts (total time = 15 minutes). The sprint-specific warm-up involved jogging, dynamic exercises and sprinting drills …

A Multi-Directional Treadmill Training Program For Improving Gait, Balance, And Mobility In Individuals With Parkinson’S Disease: A Case Series, Kimberly Smith, Kurt Jackson, Kimberly Edginton-Bigelow, Lloyd Laubach

International Journal of Exercise Science

International Journal of Exercise Science 8(4): 372-384, 2015. Treadmill training is a commonly used intervention for improving gait in people with Parkinson’s disease (PD). However, little is known about how treadmill training may also influence balance and other aspects of mobility. The purpose of this case series was to explore the feasibility and possible benefits of multi-directional treadmill training for individuals with PD. Four participants (62.3 ± 6.5 yrs, Hoehn & Yahr 2-4) performed 8 weeks of treadmill training 3 times per week. Weeks 1-4 included forward walking only, while weeks 5-8 included forward and multi-directional walking. Participants were tested …

Seasonal Variation In The Distribution Of Daily Stepping In 11-13 Year Old School Children, Paul Mccrorie, Elaine Duncan, Malcolm Granat, Benedict Stansfield

International Journal of Exercise Science

International Journal of Exercise Science 8(4): 358-371, 2015. Seasonality studies in adolescent’s physical activity (PA) tend to report total PA (e.g. steps/day) rather than more specific detail such as steps/hour. This study compared the detailed changes in PA between seasons. Thirty three adolescents (baseline age 12.2 ± 0.3y) wore the activPAL activity monitor for 8 days on two occasions. Steps/day were higher in summer (Mdn = 12,879) than winter (Mdn = 10,512), p.05), however, boys had significantly higher step counts in summer between ’13:00-14:00’ (p=.023), ’19:00-20:00’ (p=.032) and ‘20:00-21:00’ (p=.023). Total steps/day masked sex differences within specific hours of the …

Tactical Athletes: An Integrated Approach To Understanding And Enhancing The Health And Performance Of Firefighters-In-Training, Stacy L. Gnacinski, Barbara B. Meyer, David J. Cornell, Jason Mims, Kathryn R. Zalewski, Kyle T. Ebersole

International Journal of Exercise Science

International Journal of Exercise Science 8(4): 341-357, 2015. In an effort to reduce the rates of firefighter fatality, injury, and workplace stress, there has been a call for research to advance knowledge of firefighting performance and injury prevention. Physical and psychological variables important to firefighter health and performance have been identified, yet the interrelated nature of these variables has been overlooked. Given the overlap between the physical and psychological demands of firefighting and sport, and given that an integrated framework has been used in the sport domain to guide athlete health and performance research and practice, firefighter organizations could benefit …

Performance And Perceptual Responses Of Collegiate Female Soccer Players To A Practical External And Internal Cooling Protocol, Rachel L. Holm, Veronika Pribyslavska, Samantha L. Johnson, Jordan B. Lowe, Mary C. Stevenson-Wilcoxson, Eric M. Scudamore, James M. Green, Charlie P. Katica, Eric K. O'Neal

International Journal of Exercise Science

International Journal of Exercise Science 8(4): 331-340, 2015. This study examined practical pre- and mid practice cooling interventions on running performance, perceived exertion (RPE), and thermal sensation (TS) during soccer. During two formal pre-season practices female, NCAA Division II soccer players participated in three, 15 min scrimmage bouts followed by a 4^th 10 min bout. Following the 1^st, 2^nd, and 3^rd bouts, 8 field position players completed competitive sets of two, 30 yard sprints against other team members with time recorded between 5 and 30 yards. After the 4^th bout, players completed an …

Validation Of Maximal Heart Rate Prediction Equations Based On Sex And Physical Activity Status, Stephen J. Roy, J.L. Mccrory

International Journal of Exercise Science

International Journal of Exercise Science 8(4): 318-330, 2015. The purpose of the study was to determine if measured maximal heart rate (HR_max) was affected by sex or aerobic training status, and to determine the accuracy of three common clinical age-prediction maximal heart rate regression equations used to predict HR_max: HR_max = 220 – age, HR_max = 226 – age, and HR_max = 208 – (0.7 ∙ age). Fifty-two participants in total, 30 of which were in the active group (15 M, 15 F) and 22 subjects in the sedentary group (9 M, …

Preferences Toward Gender Of Coach And Perceptions Of Roles Of Basketball Coaches, Jacqui L. Kalin, Jennifer J. Waldron

International Journal of Exercise Science

International Journal of Exercise Science 8(4): 303-317. Framed within role congruity theory this study examined (a) if female collegiate basketball players have a preference toward male or female head basketball coaches, (b) if the gender and enjoyment level of past head coaches influence preferences toward a male or female head coach and/or influence the perceived roles of women’s basketball head coaches, and (c) if there is a relationship between the perceived roles of women’s basketball head coaches and female collegiate basketball players’ preferences toward male or female head coaches. Fifty-nine women’s basketball players from 10 Division I universities completed a …

Evolution From Electrophysiologic To Hemodynamic Monitoring: The Story Of Left Atrial And Pulmonary Artery Pressure Monitors, Deirdre M. Mooney, Erik Fung, Rahul N. Doshi, David M. Shavelle

Dartmouth Scholarship

Heart failure (HF) is a costly, challenging and highly prevalent medical condition. Hospitalization for acute decompensation is associated with high morbidity and mortality. Despite application of evidence-based medical therapies and technologies, HF remains a formidable challenge for virtually all healthcare systems. Repeat hospitalizations for acute decompensated HF (ADHF) can have major financial impact on institutions and resources. Early and accurate identification of impending ADHF is of paramount importance yet there is limited high quality evidence or infrastructure to guide management in the outpatient setting. Historically, ADHF was identified by physical exam findings or invasive hemodynamic monitoring during a hospital admission; …

Genetics Ignite Focus On Microglial Inflammation In Alzheimer's Disease, Manasi Malik, Ishita Parikh, Jared B. Vasquez, Conor Smith, Leon Tai, Guojun Bu, Mary Jo Ladu, David W. Fardo, G. William Rebeck, Steven Estus

Physiology Faculty Publications

In the past five years, a series of large-scale genetic studies have revealed novel risk factors for Alzheimer's disease (AD). Analyses of these risk factors have focused attention upon the role of immune processes in AD, specifically microglial function. In this review, we discuss interpretation of genetic studies. We then focus upon six genes implicated by AD genetics that impact microglial function: TREM2, CD33, CR1, ABCA7, SHIP1, and APOE. We review the literature regarding the biological functions of these six proteins and their putative role in AD pathogenesis. We then present a model for how …

Relevance Of The Carotid Body Chemoreflex In The Progression Of Heart Failure., David C. Andrade, Claudia Lucero, Camilo Toledo, Carlos Madrid, Noah J. Marcus, Harold D. Schultz, Rodrigo Del Rio

Journal Articles: Cellular & Integrative Physiology

Chronic heart failure (CHF) is a global health problem affecting millions of people. Autonomic dysfunction and disordered breathing patterns are commonly observed in patients with CHF, and both are strongly related to poor prognosis and high mortality risk. Tonic activation of carotid body (CB) chemoreceptors contributes to sympathoexcitation and disordered breathing patterns in experimental models of CHF. Recent studies show that ablation of the CB chemoreceptors improves autonomic function and breathing control in CHF and improves survival. These exciting findings indicate that alterations in CB function are critical to the progression of CHF. Therefore, better understanding of the physiology of …

A Novel C-Terminal Cib2 (Calcium And Integrin Binding Protein 2) Mutation Associated With Non-Syndromic Hearing Loss In A Hispanic Family, Kunjan Patel, Arnaud P. Giese, J. M. Grossheim, Rashima S. Hegde, Maria Delio, Joy Samanich, Saima Riazuddin, Gregory I. Frolenkov, Jinlu Cai, Zubair M. Ahmed, Bernice E. Morrow

Physiology Faculty Publications

Hearing loss is a complex disorder caused by both genetic and environmental factors. Previously, mutations in CIB2 have been identified as a common cause of genetic hearing loss in Pakistani and Turkish populations. Here we report a novel (c.556C>T; p.(Arg186Trp)) transition mutation in the CIB2 gene identified through whole exome sequencing (WES) in a Caribbean Hispanic family with non-syndromic hearing loss. CIB2 belongs to the family of calcium-and integrin-binding (CIB) proteins. The carboxy-termini of CIB proteins are associated with calcium binding and intracellular signaling. The p.(Arg186Trp) mutation is localized within predicted type II PDZ binding ligand at the carboxy …

Kinematics And Hydrodynamics Of Cephalopod Turning Performance In Routine Swimming And Predatory Attacks, Rachel A. Jastrebsky

Biological Sciences Theses & Dissertations

Steady rectilinear swimming has received considerable attention in aquatic animal locomotion studies. Unsteady swimming movements, however, represent a large portion of many aquatic animals’ locomotive repertoire and have not been examined extensively. This study incorporates kinematic analyses of routine turning performance of brief squid Lolliguncula brevis and dwarf cuttlefish Sepia bandensis (Chapter 2), 3D velocimetry techniques to examine hydrodynamic turning performance of L. brevis (Chapter 3) and kinematic analyses of turning performance of L. brevis during predatory attacks on shrimp and fish prey (Chapter 4).

Both L. brevis and S. bandensis demonstrated high maneuverability, having the lowest measures of length-specific …

Effects Of Supplemental Hydration On Physiology And Behavior Of Northern Pacific Rattlesnakes (Crotalus Oreganus Oreganus), Griffin D. Capehart

Master's Theses

Hydration is a critical element for many physiological processes in vertebrates, such as protein production, innate immunity, and behavioral processes such as daily activity and thermoregulation. Few studies have directly assessed the effect of hydration on these animals in nature. While it seems intuitive that drought is stressful to animals, studies examining drought are typically observational and fail to assess how the hydration state of these animals influences their physiology and behavior. We tested for an effect of hydration on several physiological and behavioral parameters in Northern Pacific rattlesnakes (Crotalus oreganus oreganus) by experimentally manipulating hydration levels in …

The Role Of Perineuronal Nets In Regulating Barrel Cortex Physiology, Philip Chu

Dissertations, Theses, and Capstone Projects

The ability of the brain to adapt to changing environmental conditions is regulated by genetic and environmental factors. One component of the brain extracellular matrix, a scaffold of proteins and proteoglycans, tightly ensheaths the soma and proximal processes of neurons. These Perineuronal nets (PNNs) play protective and structural roles in the brain, but also regulate plasticity and behavior. Their developmental expression is highly attenuated following sensory deprivation, or pharmacological silencing of neuronal activity. Thus, PNNs contribute to the activity dependent regulation of plasticity in the brain. Although PNNs are relatively ubiquitous in the neocortex, little is known about the degree …