Past Post-Doctoral Events

SPRING 2017

Post-Doctoral Journal Club

 Scientists/Activists

Wednesday, February 22             

12:00 noon, PAIS 464

Discussion leader:  Katherine Bryant (Anthropology). 

Two articles will be discussed.  The first is a sociology research article on the changes to public trust of science in the US over time:   Gauchat G. 2012. Politicization of Science in the Public Sphere: A Study of Public Trust in the United States, 1974-2010. American Sociological Review 77:167-187

The second is a Time article on the anti-science politics of the Trump administration, available here.  

Post-Doctoral Facilitated Discussion

Autobiographical Memory: From Self to Society

Friday, March 17

12:00 noon, PAIS 464

Presenter:  Jordan Booker (Psychology) 

Jordan Booker (Psychology) will give a presentation entitled “Autobiographical Memory: From Self to Society.” Open discussion will follow the presentation, led by Dr. Booker. 

Post-Doctoral Book Club

NeuroTribes

Wednesday, April 12      

12:00 noon, PAIS 464. 

Discussion leader:  Christina Tzeng (Psychology).                

The book for this session will be NeuroTribes: The Legacy of Autism and the Future of Neurodiversity by Steve Silberman.  The book can be purchased in print or digital format here.

FALL 2015 SEMESTER

Tuesday, November 17, 2015     

‘Precision Medicine’ Approach for Oxytocin’s Role in Social Behavior, from Rodents to Humans

Elissar Andari 
Yerkes National Primate Research Center
Emory University

The neuropeptide oxytocin modulates a range of complex behaviors from parental care to pair bonding and memory. By using knockout mice, we show that oxytocin plays a role in the memory formation of social events. We also found that oxytocin is likely to play a significant role in the regulation of fear expression and extinction of negative events. Furthermore, through pharmacological manipulations, we observed that central administration of oxytocin antagonist to socially monogamous prairie voles abolishes their prosocial-like responses to the stress of others. There is growing evidence for the role of this molecule in promoting socio-emotional skills in healthy subjects and in neurodevelopmental disorders such as Autism Spectrum Disorder (ASD). We show that acute intranasal administration of oxytocin impacts social behavior and the BOLD activity of key brain regions involved in perception and emotional processes in individuals with ASD. Here, I will discuss the social dysfunction of ASD and oxytocin’s role in social behavior within a “precision medicine” approach that accounts for phenotype, outcome measures and inter-individual variability.

The Oral Microbiome of Pregnant Smokers and Marijuana Users

Irene Yang 
School of Nursing
Emory University

In 2013, 11.39% of births in the US were preterm. African American (AA) women have a higher risk of preterm birth and premature infants are vulnerable to a host of immediate and long-term complications. Tobacco smoking and marijuana use are associated with the occurrence of preterm birth. Biological mechanisms underlying these associations, however, are not well understood. Periodontal disease may be a mediating mechanism by virtue of the dysregulation it causes in the normal pregnancy
systemic inflammatory state. Periodontal disease results from an infection of microorganisms at the tooth-gingival interface, and pregnant women are particularly susceptible to this infection due to the hormonal shifts occurring in their body. Exposure to tobacco and marijuana smoke increases that vulnerability. This presentation will describe the oral microbiome of pregnant African American non-smokers, tobacco smokers, and marijuana smokers, and any relationship that their microbial environment may have with the occurrence of preterm birth.

SPRING 2015 SEMESTER

Tuesday, March 17th, 2015

Alternative Approaches to Comparative Cognitive Neuroscience

Peter Cook
Center for Neuropolicy
Emory University 

Rodent models for comparative neuroscience are flexible, cheap, highly controlled, and, consequently, pervasive. However, productive as they can be—particularly at the molecular level—these dominant models don’t accurately represent within- and cross-species variability in natural populations and are thus not always ecologically valid. Alternative models may be less expedient, but may also better fit certain research questions—they can also be more humane. I’ll address three representative lines of research in which I’ve been involved: 1. Characterization of the neurobehavioral impact of naturally occurring domoic acid toxicosis in a large sample of wild sea lions undergoing rehabilitation, 2. Opportunistic post-mortem, high-resolution diffusion tensor imaging of white matter tracts in the brains of a range of species, and 3. Awake, unrestrained fMRI conducted cooperatively with domestic dogs. Each of these projects has provided novel insight into the neurocognitive functioning of particular species, and the results emphasize the complicated connections between brain, behavior, and environment. 

Behavioral and Biochemical Effects of 3,4-Methelynedioxymethamphetamine (MDMA) on the Extinction of Fear Memory

Matthew B. Young
Neuroscience
Emory University 

3,4-methelynedioxymethamphetamine (MDMA, ‘ecstasy’) has been reported to have long-term positive effects on symptoms of post-traumatic stress disorder (PTSD) when combined with psychotherapy. It has been theorized that recovery from PTSD requires extinction of the conditioned fear response to a stimulus that no longer signals danger. Using behavioral and biochemical measures of fear learning, we demonstrate that MDMA increases fear extinction learning, providing a mechanistic basis for clinical findings with MDMA. 

FALL 2014 SEMESTER

Thursday, October 30th, 2014

Key to Universal Flu Vaccine: Embrace the Unfamiliar

Ali Ellebedy
Microbiology and Immunology
Emory University School of Medicine

Vaccination is the most effective means of attaining protection against influenza viruses. Conventional protective anti-influenza antibodies primarily target few sites within the globular head region of influenza virus hemagglutinin (HA), the principal target of virus-neutralizing antibody responses. However, the constantly evolving nature of influenza viruses enable them to escape pre-existing immune surveillance thwarting public health efforts to control influenza annual epidemics. One solution is to elicit protective antibodies directed against highly conserved epitopes, such as those within the stem region of HA. Current influenza vaccination strategies rely on changing the HA components of the annual vaccine to ensure that they match circulating influenza strains. Our data show that annual influenza vaccines induce antibody responses that are largely directed against the highly variable HA head region, which are protective, but are strain specific and does not provide the much-sought broad protection. In contrast, immunization with HAs derived from influenza virus strains that are currently not circulating in humans (e.g. H5N1) did substantially increase HA stem-specific responses and thus represents a viable strategy for promoting broadly protective immunity against influenza. 

ADRA1A Locus and Response to Treatment of Major Depression

Adriana Lori
Human Genetics
Emory University School of Medicine

Major Depressive Disorder (MDD) is a leading cause of dis-ability worldwide. While effective treatments for MDD are available, responses to treatment for MDD are often sub-optimal, with remission occurring in less than 50% of patients.   ADRA1A encodes the α1 adrenergic receptor, which is a key brain protein that mediates signaling by the neurotransmitter norepinephrine. Several lines of evidence suggest the importance of ADRA1A as a gene influencing response to treatment in MDD; among these, our preliminary data from 82 patients randomly assigned to two lines of treatment (SSRI escitalopram or CBT) showed a statistical relationship between one SNP in the ADRA1a region and patterns of brain activity (PET) associated with achievement of remission. To further explore whether ADRA1A polymorphisms may influence achievement of remission in response to antidepresssant treatment, the 82 patients who participated in the treatment study mentioned above will be completely sequenced for the ADRA1A locus to identify unique SNPs that impact the function of the gene. If we identified SNPs or mutations that distinguish responders vs non-responders, we could i) establish a line of therapy for the responders ii) search new strategies and options for non-responders c) establish cell lines and animal models to experiment new pharmaco-therapies in non-responders. Research funded by the Brain and Behavior Research Foundation (NARSAD).

SPRING 2014 SEMESTER

Friday, February 14         

Acquisition of Paleolithic Toolmaking Abilities Involves Structural Remodeling to Inferior Frontoparietal Regions

Erin Hecht
Department of Anthropology
Emory University

Human ancestors first intentionally modified stones into tools about 2.6 million years ago, initiating a cascading increase in technological complexity that continues today.  A parallel trend of brain expansion during the Paleolithic has motivated over 100 years of theorizing linking stone toolmaking and human brain evolution, but empirical support remains limited.  The current study aimed to identify neuroanatomical targets of natural selection acting on toolmaking ability.  Subjects received MRI and DTI scans before, during, and after an intensive, two-year Paleolithic toolmaking training program.  White matter fractional anisotropy (FA) showed changes in branches of the superior longitudinal fasciculus leading into left supramarginal gyrus, bilateral ventral precentral gyri, and right inferior frontal gyrus pars triangularis.  FA correlated with training hours, increasing from Scan 1-2, a period of intense training, and decreasing from Scan 2-3, a period of reduced training.  Similarly, voxel-based morphometry found gray matter expansion in the left supramarginal gyrus from Scan 1-2 and a reversal of this effect from Scan 2-3.  Probabilistic tractography confirmed that white matter changes projected to gray matter changes and to other regions that activate during Paleolithic toolmaking.  These results show that the acquisition of Paleolithic toolmaking skills requires the re-allocation of structural resources and likely affected the trajectory of human brain evolution.  These regions participate not only in toolmaking but also in other complex functions including action planning and language. This substantiates the hypothesized co-evolution of these functions and supports the interaction between technological, social, communicative, and neural complexity in human evolution.

Application of Wavelets and Machine Learning to Detect Electromyographic Activity in Human Sleep

Jacqueline Fairley 
Department of Neurology
Emory University

Manual/visual identification of phasic muscle activity, during human sleep, represents a potentially reliable metric for distinguishing between neurodegenerative disorder populations and age-matched controls. However, visual scoring of PEM activity is laborious, time consuming, and potentially error prone-preventing feasible implementation within a clinical setting. Therefore, in this talk I will discuss how wavelets and machine learning can be used to automatically identify phasic muscle activity during human sleep via the polysomnogram.  More specifically, I will focus on Symlet and Daubechies wavelet families, principle component analysis, forward floating search feature selection, and linear classification. Results from this work provide evidence that automated detection compares satisfactorily to expert manual scoring (>90% classification performance) in 11/12 datasets.

Friday, February 28th

Proteomics and Its Relevance to Dystonia Research and Medicine

Teresa Douglas 
Department of Neurology
Emory University

Proteomics involves large scale analysis of functional proteins and their physiological interactions. Technological advancements have improved the sensitivity and scale of proteomic analysis thus leading to a dramatic expansion of proteomics methods in health and disease research.  The neurosciences have also adopted proteomics in the effort to identify pathological causes of several common diseases and identify therapeutic targets. Some earlier discoveries have already been translated into clinical care. Dystonia, a muscle movement disorder that is often debilitating and can affect persons of any age, is among the lesser known neurological conditions. Like many lesser known neurological diseases, the field of dystonia research and care is in urgent need of clinical breakthroughs stemming from modern proteomics analyses. Current and upcoming proteomics research as it relates to dystonia, limitations of proteomics analysis, along with the potential benefits to dystonia affected patients as proteomics technology continues to advance and become more applicable to both research efforts and medical care will be covered in the presentation.

Reciprocal Effect of Type I IFN Signaling on CD8 T cells: An Intricate Phenomenon 

Siddhartha Bhaumik
Emory Vaccine Center
Emory School of Medicine

Type I Interferons (IFNs) play a major role in initiating the innate immune response and shaping the nature of the adaptive immune response. Previous work from our laboratory has shown that the induction and requirement of Type I IFNs on CD8 T cells for their clonal expansion and memory generation depends largely on the pathogen. In this context, there is very little known about the effect of Type I IFNs on the CD8 T cell development during West Nile Virus (WNV) infection, which in humans the clinical manifestations can range from feeble fever to fatal meningoencephalitis. Here, using a murine footpad infection model we addressed two questions: (1) what happens to virus-specific CD8 T cell responses if the infected host is devoid of IFN-I signaling, (2) what happens to virus-specific CD8 response if only CD8 T cells lack IFN-I signaling. Our results show that lack of IFN-I signaling in the host lead to increased susceptibility to WNV infection and exaggerated CD8 T cell clonal expansion, while lack of IFN-I signaling only on the CD8 T cells showed a diminished clonal expansion. Together our results suggest that the IFN-I mediated innate viral control is important for determining the measure of CD8 T cell effector and memory differentiation. This knowledge has implications in the development of vaccine strategies against the neurotropic WNV infection.

Wednesday, March 19th

Utilizing a Unique Animal Model to Connect Genes and Social Behavior

Wendy Zinzow-Kramer
Department of Psychology
Emory University

Over the past decade, behavioral scientists have become increasingly interested in genetics as a tool to predict behavior and identify risk factors for psychiatric illness. The link between genetic polymorphisms and behavioral constructs such as “aggression” is still lacking, largely because of a failure to consider the intermediary steps that happen at the levels of gene transcription and protein function. We utilize a songbird model, the white-throated sparrow, which allows us to study social behavior in a natural environment and correlate behavior with gene expression. This species exhibits a plumage polymorphism that correlates with many aspects of social behavior. Individuals with a white stripe (WS) on the crown are more aggressive and have higher song rates than individuals with a tan stripe (TS). The plumage polymorphism is linked to a chromosomal rearrangement, presenting a unique opportunity to study the relationship between genes and social behavior. The powerful and exciting technology of next-generation sequencing will be utilized to identify genes in the brain that vary in expression with relation to both plumage morph and aggressive behavior. Because genes and pathways that regulate social behavior are highly conserved, the findings of this research will be relevant to the mechanisms underlying social behavior in all vertebrates, including humans. 

Neurobiological Pathways Predicting Risk for Post-Traumatic Stress Disorder

Jennifer Stevens 
Department of Psychiatry and Behavioral Sciences
Emory University

Although a large percentage of the general population experiences a significant traumatic event during their lifetime, only about 7% develop post-traumatic stress disorder (PTSD).  What are the factors that contribute to resilience or vulnerability to PTSD after a trauma?  This question has been difficult to answer, particularly because PTSD is a complex disorder with symptoms that vary widely from individual to individual. We have found several examples showing how individual differences in brain function can increase our ability to explain risk for PTSD, indicating mechanisms for the contributions of both genetic and experiential risk factors.  I will discuss these findings and focus on possible neurobiological pathways for the heightened risk of PTSD in women relative to men.

FALL 2013 SEMESTER

Wednesday, October 16, 2013
12:00 noon

Jennifer Mascaro, PhD
Department of Anthropology
Emory University 

The Biological Bases of Individual Variation in Paternal Nurturing

Despite the well-documented benefits afforded the children of invested fathers in modern western societies, some fathers choose not to invest in their children. Why do some men make this choice? The overall goal of this project was to identify the biological influences on paternal nurturing behavior. To that end, we recruited fathers of children aged 1-2, as well as age-matched non-fathers, and acquired measures of reproductive biology, and genetic, hormonal, neurobiological, self-report, and behavioral data. Fathers were compared to non-fathers, and individual variation in paternal behavior was examined with respect to reproductive biology, hormones, genetics, and neurobiology. We identified hormones and neural activity that differed between fathers and non-fathers, as well as neural activity that predicted paternal attitudes and caregiving. Our pattern of results further suggested that the biology of human males reflects a trade-off between mating effort and parenting effort.

Faith Bartz, PhD
Clean Greens Project Manager
Rollins School of Public Health
Emory University 

Microbial Profiles of Fresh Produce and the Farm Environment: Food Safety on the U.S-Mexico Border

Although produce associated enteric disease outbreaks are responsible for serious economic losses, morbidity, and mortality, few studies have directly identified routes of contamination at the farm or packing facility. The goal of our study was to quantify fecal indicators in potential environmental sources of contamination and identify their role in produce contamination. We took composite samples of fresh produce (including rinses of cantaloupe, jalapeño, and tomato) and matched irrigation water, soil, and farm worker hand rinses from 10 farms in northern Mexico. These samples represented several steps in the production process, spanning from pre-harvest through harvest and packaging. From each sample, generic E. coli, fecal coliforms, Enterococcus, and somatic coliphages were enumerated. The magnitude of association between produce and environmental sample contamination was assessed . The presence of E. coli, coliforms, and coliphage was significantly associated between hands and produce. The presence of E. coli and coliforms was also significantly associated between soil and produce. The concentrations of E. coli, Enterococcus, coliforms, and coliphage were significantly and highly correlated between hands and produce, but not between soil or water and produce. These trends were also observed when analyses were adjusted for crop type and production step. These results suggest that decreasing farm worker hand contamination would be an effective intervention to decrease microbial contamination of produce and improve food safety on farms.

Thursday, November 21, 2013
12:00 noon

POST-DOCTORAL LUNCH SYMPOSIUM

Otis Smart, PhD
Department of Neurosurgery
Emory University School of Medicine

Long-term Lateral Changes in Bilateral Hippocampal Seizure Onset Zones

This study describes seizure laterality and localization changes over 500 consecutive days in a patient with
bilateral temporal lobe epilepsy (BTLE) and implanted NeuroPace RNS™ System. During a continuous
two-year time period, the RNS™ device stored 54 hippocampal electrocorticography (ECoG) seizures,
which we analyzed to determine their distribution and time variance across hippocampi. We report
nonrandom long-term seizure laterality and localization variations, especially in the first 200 days
postimplant, despite equivalent total seizure counts in both hippocampi. This case suggests that hippocampal
seizures dynamically progress over extensive timescales.

Sheena Brown, PhD
Asthma Clinical Research Program 
Emory University School of Medicine

The Role of Dietary Sulfur Amino Acids and Oxidant Stress in Childhood Asthma

Asthma, one of the most common chronic diseases seen in children, affects more than 25 million people in the United States annually.  While asthma symptoms are intermittent in many children, some have persistent symptoms that necessitate daily treatment. While the mechanisms of severe asthma are not entirely clear, the disorder is likely related to oxidant stress from antioxidant depletion. Our group has previously shown that children with severe asthma have decreased concentrations of cysteine, an antioxidant, in the airways and the systemic circulation. Because cysteine is synthesized from methionine, a sulfur amino acid (SAA) that is ingested from the diet, the overarching hypothesis is that cysteine bioavailability is decreased in children with severe asthma as a function of both altered dietary SAA intake and SAA metabolism. Following characterization, lung function testing, measurement of lung inflammation, and venipuncture were performed. Dietary intake of SAAs, systemic levels of antioxidants, SAA metabolites, and genes involved in SAA metabolism were also assessed. Our results showed there is no difference in SAA intake among the groups. However, severe asthmatics displayed decreased concentrations of cysteine, SAAs metabolites, and genes involved in the SAA metabolism pathway. These results suggest the increased oxidant stress and symptoms seen in sever asthmatics may be due to altered metabolism of SAAs.

SPRING 2013 SEMESTER

Wednesday, February 6, 2013
Noon until 1:30 pm

Demystifying Signal Processing Techniques for Neuroscience Applications

Jacqueline Fairley, PhD
Department of Neurology
Emory University

Signal processing involves the application of mathematics to analyze neuroscientific data. Although there are various signal processing tools, open source and commercially available, many may be overwhelming to the first time user and often do not explicitly provide information on how to apply these tools.  This talk aims to provide insight on salient aspects of signal processing for neuroscience applications by providing case study examples using waking electroencephalogram (EEG) and electromyogram (EMG) data sets from humans diagnosed with sleep-wake and neurodegenerative disorders, respectively. 

More specifically, information will be provided on pre-processing, data characterization, and post-processing aspects of biological time series analysis.  To highlight these topics waking EEG data will be provided from a primary hypersomnia clinical trial and from a Rapid Eye Movement Behavior Disorder research protocol.  Information from this talk will provide insight regarding the signal processing tools available and best methods on how to best apply them in neuroscience research.     


The Primate Gambling Task

Darby Proctor, PhD
Yerkes National Primate Research Center
Emory University

Humans show a strong propensity to engage in gambling behaviors. Decisions to gamble are often based on feelings, irrational thoughts, and a misunderstanding of odds rather than on probabilities of earning a net profit. This leads to a conflict between the chance of an immediate payout from the bet and the long-term economic consequences of gambling behavior. Why humans evolved to make these gambling decisions is unclear. Understanding the evolutionary roots of this behavior, by examining the other primates, could shed light on this issue. Here, we adapted a human gambling experiment, the Iowa Gambling Task (IGT), to be suitable for nonhuman primates. In the traditional IGT, participants are asked to pick from an array of decks of cards. Each card within a deck contains either a gain or a loss of a reward. One deck has a relatively consistent payout, while another deck is not as profitable, but is also variable, potentially paying more on an individual trial. Typical humans develop a preference for the consistent deck which nets the largest overall gain. In the current study, chimpanzees respond similarly to humans in a modified version of this task. Capuchin monkeys however, react differently than both humans and chimpanzees. This suggests that the evolutionary roots of human gambling behaviors are shared with chimpanzees, but not with capuchins.

Wednesday, March 6, 2013
Noon until 1:30 pm

Watching Single Enzymes at Work: Regulation of DNA Supercoil Density by Gyrase Orthologs

Monica Fernandez-Sierra, PhD
Department of Physics
Emory University

Type II topoisomerases maintain DNA topology by regulating the level of supercoiling of chromosomes. DNA gyrase is a unique and highly conserved bacterial Type II topoisomerase which is able to introduce negative supercoils into the genome. All gyrase orthologs have homologous catalytic domains, although some species-specific regions have been found. Surprisingly, in mid-log phase growth, the Salmonella typhimurium genome has 15% less supercoil density than that of Escherichia coli. We hypothesized that this contrast may be due to differences in the activities of the S. typhimurium and E.coli gyrases. Using magnetic-tweezers, we assessed the supercoiling and relaxation activities of these two gyrase orthologs and found that under single-enzyme conditions and 0.6-pN tension, both enzymes relax positively supercoiled DNA at similar rates although S. typhimurium gyrase pauses more often. At high enzyme concentration and lower tensions, S. typhimurium gyrase introduces negative supercoils faster and to a larger extent than E. coli gyrase. Our findings, along with protein sequence analyses, indicate that amino acid differences in the C-terminal domain of the GyrA subunits may affect the binding and wrapping of DNA by the two enzymes. These results support the notion that while amino acid substitutions among gyrase orthologs produce distinct supercoiling activities, other factors contribute to the overall supercoiling level of the genomes of different organisms.


The Ups and Downs of Female Anxiety: Estrogen and Menstrual Cycle Effects on Fear Regulation

Ebony Glover, PhD
Department of Psychiatry and Behavioral Sciences
Emory University School of Medicine 

Post-traumatic stress disorder (PTSD) is a severe and debilitating anxiety disorder associated with neurobiological abnormalities that can develop after exposure to a traumatic event. Women have a two-fold greater risk for developing PTSD than men. However, the influence of female gonadal hormones, especially estrogen, on fear regulation is not well understood. Our findings show that the inability to inhibit fear responses in safe conditions may be a biomarker for PTSD. I will present recent findings that low estrogen is associated with deficits in fear inhibition in naturally cycling women with PTSD. Hence, low estrogen may be a vulnerability factor for PTSD risk in women due to its influence on fear regulation.

FALL 2012 SEMESTER

Thursday, October 11, 2012
Noon until 1:30 pm, PAIS 464

Vocal communication in bonobos: meaningful food-call sequences and the social use of copulation calls 

Zanna Clay, PhD
Department of Psychology
Emory University

Bonobos (Pan paniscus) are still one of the least well understood of the great apes, largely remaining in the shadow of their better known cousins, the chimpanzees (Pan troglodytes). This is especially evident in the domain of communication, with bonobo vocal behaviour an especially neglected field of study. Here, I address this issue by presenting a series of studies examining natural vocal communication in bonobos, focusing on the role of vocalisations during two contexts, food discovery and sex. In the feeding context, I combined observational and experimental techniques to examine whether bonobos produce and understand vocalisations that convey meaningful information about food quality. Results indicated that bonobos combine food-associated calls into sequences in a way that relates to food quality, which receivers use to guide foraging decisions.cNext, I present a series of studies that explore the vocal behaviour of female bonobos during sexual interactions with males and other females. Beyond their reproductive function, female bonobos use copulation calls as social signals, to communicate a range of social information and also are subject to audience effects. Overall, I will discuss the relevance of studying primate vocalisations to investigate the underlying cognition and suggest that vocalisations are important behavioural tools for bonobos to navigate their social and physical worlds.


Modeling the Mind:  Memory, Text and Violence in Faulkner’s Most Furious Fictions

John Michael Corrigan, PhD
Fox Center for Humanistic Inquiry
Emory University

Where ancient tragedy represented violence as a disease that, once unleashed, could wipe out whole communities, William Faulkner is unique among modernists in visualizing this tradition of violence in terms of cognition and textuality. Anticipating the technology of neuroimaging, Faulkner used Southern architecture to image the structure of the mind so that antebellum plantation mansions serve as diseased maps of memory and town centers model the way in which violence hampers cognitive processing. This imaging technique extends to the visual architecture of the page itself. Passages in which the threat of violence is greatest most often turn metafictional, forcing the reader to consider his own powerlessness in relation to the static nature of the two-dimensional page. If modernism celebrated human agency, vaunting the reader’s power to infuse texts with meaning, Faulkner depicts scenes in which violence breaks outside of the bounds of narrative to jar the reader in his or her accustomed posture. Even something as simple as a text can pose a threat. Indeed, the reader doesn’t just extend his mind into a text; rather, he finds that words, even those long dead, can be infected with what they represent.

Thursday, November 8, 2012
Noon until 1:30 pm, PAIS 464

Oxytocin Receptor Knockdown Prairie Voles Display Behavioral Deficits with Relevance to Autism and Are a Model for the Screening of Pharmacotherapeutics

Alaine Keebaugh, PhD
Yerkes National Primate Research Center
Emory University 

Studies have implicated oxytocin (OT) and its receptor (OXTR) in the modulation of social behaviors, and disruptions in this system have been linked to diseases of social deficits such as autism spectrum disorder (ASD).  Recently, Oxtr knockout mice have been shown to model multiple components of the ASD phenotype and highlight the importance of detailed behavioral phenotyping with relevance to social cognition.  We extend these studies in mice by site-specifically manipulating Oxtr in the prairie vole, a social rodent with an unusual repertoire of social behaviors.  Here, we use viral-mediated RNA interference (RNAi) to knockdown expression of Oxtr within the nucleus accumbens (NAcc) of prepubertal female prairie voles.  This localized gene knockdown blocked the formation of a pair bond, reduced spontaneous nurturing behavior and maternal care and lead to deficits in communication.  Further, we found that acute Melanotan II administration can rescue pair bond formation, supporting a role for this drug in pharmacotherapy aimed at enhancing social behavior by targeting the oxytocinergic system. These results underscore the potential of using viral-mediated RNAi for the rapid production and testing of genetic disease models in this species and for identifying pharmacotherapeutics for diseases of social deficits such as ASD. 


To Sleep, Perchance to Train the Brain

Michael Scullin, PhD
Department of Neurology
Emory University

Working memory is essential to higher order cognition (e.g. fluid intelligence) and to performance of daily activities. Though working memory was traditionally thought to be inflexible, recent studies report that working memory can be trained over days and weeks. An intriguing idea is that sleep--in particular, the neural plasticity occurring during slow-wave sleep--facilitates working memory improvements. In a recent paper, we studied working memory training across 48 hours in patients with neurodegenerative disease. All patients underwent overnight polysomnography recording during the training interval to measure sleep physiology. We found that working memory improvements were specifically associated with a nocturnal sleep interval in Parkinson’s disease patients. Furthermore, the working memory improvements were positively correlated with the amount of slow-wave sleep that patients obtained between training sessions and negatively correlated with presence of even mild sleep apnea. The translational implication is that working memory is potentially modifiable in patients with Parkinson’s disease but that sleep disturbances may first need to be corrected.