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Neuroscience at Scholarship Sewanee 2016

‌Scholarship Sewanee is a celebration of student research at the University, centering around class projects, community-based projects, or independent student research.  They include data collection and analysis during the previous summer as well as the academic year, both on- and off-campus.  It is an expansion of Scientific Sewanee, first held in April 1994, with an Invited Lecture and 20 student poster presentations.

Scholarship Sewanee 2016 included 38 oral presentations held Friday morning and later in the afternoon. The McCrady Invited Lecture was held at 1 p.m.;  69 poster presentations starting at 2:15 p.m. (with researchers remaining close to their posters to discuss their project with those attending);  and a Sewanee Symphony Orchestra and University Choir concert Friday evening involving many student musicians.  More than 165 students were mentored by 47 Sewanee and several faculty/graduate students from other institutions – notably Yale. 

Petra Richer ’16, and Thomas Fernandez MD.  Insights from De Novo genetic variation in Tourette Syndrome.  Department of Psychiatry, Yale Univ. School of Medicine.  Mentor, Thomas Fernandez MD, Assistant Professor in the Child Study Center and of Psychiatry at Yale.  Richer is a Biology major with a minor in Neuroscience.

 Tourette syndrome (TS) is a neuropsychiatric disorder characterized by combinations of motor and vocal tics that persist for longer than one year. In the general population, 0.5-0.7% of people are affected by TS at some point in their lives. The median age of onset among children is 6 years, and tics reach the peak of their severity at approximately 10.6 ± 2.6 years of age. Twin studies have found a concordance rate of 53% in monozygotic and 8% in dizygotic twins, indicating a substantial genetic component to the disease. Current treatment options for TS vary in effectiveness among individuals and include behavioral therapy and various medications for controlling disruptive tics. Remaining questions about TS pathophysiology and a need for new and improved treatment options has prompted the study of genetic causes that underlie the disease in the hopes of identifying novel therapeutic targets and increasing our understanding of this complex disorder.

 

Gosife Donald Okoye ’16, (pictured above with Dr. Dale Peterson) Lucianna Frick, and Maximiliano Rapanelli.  Acute disruption of striatal modulation by neuronal histamine results in Tourette Syndrome-like phenomenology.  Department of Psychiatry, Yale Univ. School of Medicine.  Mentor, Dr. Thomas Fernandez of Yale.  Okoye is a Biochemistry major. Frick and Rapanelli are Associate Research Scientists in Psychiatry at Yale.  Speaker’s Choice Award for best poster (2-way tie).

Tourette Syndrome is a complex neuropsychiatric disorder characterized by pathognomic motor and vocal tics, as well as by sensory and cognitive symptoms and its pathophysiology is not well understood. Recently, a high-penetrance mutation in histidine decarboxylase (Hdc), a key enzyme in the biosynthesis of Histamine (HA), was implicated as a rare cause of TS. Hdc knockout mice recapitulate core phenomenology of TS. The finding that the tic-like stereotypes observed in HDC knockout mice were mitigated by HA infusion into the brain has focused attention on disruption of brain HA as a potential causative factor in neuropsychiatric disease especially TS. To investigate the cause of the observed effects, we used cre-infused DREADDs to reversibly inactivate histaminergic neurons chemogenetically; importantly, peripheral sources of HA are unperturbed by this manipulation, and brain development is normal.

 

 Madison Bunderson ’18.  Mood modulation by music:  neural arousal and attention.  Mentor, Assistant Professor of Psychology Brandy Tiernan.  Bunderson is a Psychology major with a minor in Neuroscience and a certificate in Creative Writing.

 Previous literature suggests that mood modulates the neural response to emotional stimuli. In the proposed study we will induce mood states with music, then use an oddball paradigm in which participants will categorize images as positive, negative, or neutral while brain activity is recorded. Our research questions include: a) if music is salient enough to change and stabilize mood and b) whether mood influences attention and arousal for negative events. We expect that mood states will elicit differential neural activity for negative images when participants are asked to categorize emotionally salient images. More specifically, neural response to negative images will be greater than the response to positive or neutral images when a positive mood is induced, an indication of increased arousal and attention shifting. The understanding of music’s influence and of the neural mechanisms underlying emotion, mood, and affect is invaluable due to their roles in our everyday life and behavior.

 

Cody Bartz ’18.  Mood and memory in college students.  Mentor, Assistant Professor of Psychology Brandy Tiernan.  Bartz is a Psychology major with a minor in Neuroscience.

Sad moods impact memory. For example, depressed individuals retrieve less information than healthy controls on episodic memory tasks. Unfortunately depression is common on college campuses, where adequate retrieval is essential for high performance and achievement. Research suggests increased cognitive load affects memory. Full time college students enrolled in extra activities may feel stressed, which, in turn, influences mood and suboptimal memory retrieval. In this experiment, we examine the relationship between mood, cognitive load, and memory retrieval. Participants will complete self-report measures of mood, memory, and current workload, followed with a computer-based task to test cognitive load and memory. We expect that higher scores on measures of depression and sad mood will perform poorly on these tasks. Moreover, we expect that increase cognitive load will impact mood. We will use the results to support students and find useful strategies to promote work-life balance.

 

Social Research Lab:  Dr. Jordan Troisi, Julian Wright ’17, Dr. Bethany Fleck (Metropolitan State University of Denver), Rachel McGill (Metropolitan State University of Denver), Garrett Heatherly ’16, Anna Bradley ’18, Meaghan Gray ’17, and Alex Evans ’16.  Grading Scheme Study.  Mentor, Assistant Professor of Psychology Jordan Troisi.  Heatherly is a Psychology Major with a minor in Neuroscience.

Many college level classes are graded on point-based systems determined by the amount of points earned throughout the semester. Students’ perceptions of the amount of points in a course have not been empirically examined. Using an experimental paradigm with online surveys, students (n = 216) at two universities reported their perceptions of college course vignettes: one in which 100 points were available and one in which 1000 points were available. Participants then completed a series of surveys. Results showed that students prefer and would be more likely to sign up for a course with a 100-point based grade scheme. Results also revealed that those in the 1000-point based condition experience more negative mood at the prospect of having points deducted. These effects were enhanced among female participants. Additionally, statistically controlling for income and race did not alter the results. We recommend that college courses offer fewer total points.ocial Research Lab:  Dr. Jordan Troisi, Julian Wright ’17, Dr. Bethany Fleck (Metropolitan State University of Denver), Rachel McGill (Metropolitan State University of Denver), Garrett Heatherly ’16, Anna Bradley ’18, Meaghan Gray ’17, and Alex Evans ’16.  Grading Scheme Study.  Mentor, Assistant Professor of Psychology Jordan Troisi.  Heatherly is a Psychology Major with a minor in Neuroscience.

 

 Yubisan Ventura ’16.  Gender differences in E-Cigarette use among adolescents.  Mentors, Dr. Grace Kong (Associate Research Scientist) and Dr. Suchitra Krishnan-Sarin (Professor), Department of Psychiatry, Yale University School of Medicine.  Ventura is a Psychology major with a Neuroscience minor.

 Studies have shown that there are gender differences in tobacco use (i.e. cigarette smoking, smokeless tobacco, cigars, pipe, etc.). Adult and adolescent males smoke more cigarettes per day than adult & adolescent females. Significantly fewer females inhale, if they do, fewer inhale deeply with every puff as compared to males. Females take fewer puffs than males and men have a larger puffing volume and longer puff duration than females. E-cigarette use continue to grow among adolescents. However, research has not analyzed whether there are gender differences in e-cigarette use. I hypothesize that there is a gender difference in e-cigarette vaping behavior among adolescents. Adolescent females will take fewer puffs as compared to adolescent males. Adolescent males will take deeper and longer puffs as compared to adolescent females.

 

‌Anna Bradley ’18, Dr. Jordan Troisi, Dr. Regan Gurung, Sara Balte ’17, Alex Evans ’16, Meaghan Gray ’17, Garrett Heatherly ’16, and Julian Wright ’17. Pride and Prejudice:  consequences of race and exposure to the Confederate Flag.  Mentor, Assistant Professor of Psychology Jordan Troisi.  Heatherly is a Psychology major with a minor in Neuroscience.  Dr. Gurung is Professorof Human Development and Psychology at the Univ. of Wisconsin Green Bay.

Past research suggests that exposure to the Confederate Flag affects judgments toward nonwhite individuals. Our study furthered this research by focusing on different racial groups’ reactions to the Confederate Flag. Participants were Sewanee students (n=41), 35 of which were white, and 6 of which were nonwhite. Participants were randomly assigned to view one of two sets of news headlines with accompanying images: one with stories featuring the Confederate Flag, and one without the flag. Afterward participants completed a series of questionnaires. Our results indicate that exposure to the Confederate Flag did not influence whites towards whites intended attitudes when encountering racism and personal attitudes about the flag. However, exposure to the Confederate Flag did significantly influence the responses of nonwhite individuals. Overall, the results suggest that exposure to the Confederate Flag has a greater impact on nonwhite individuals than white individuals.

Petra Richer ’16.  Exome sequencing in Tourette Syndrome and genetic screening in a C. elegans model of Machado Joseph Disease.  [oral presentation]  Mentors, Assistant Professor of Biology Elise Kikis and Thomas Fernandez MD, Assistant Professor in the Child Study Center and of Psychiatry at Yale.   Richer is a Biology major with a minor in Neuroscience.  Based on work at the Sewanee-at-Yale Directed Research Program.

 Gene discovery has played an integral role in elucidating mechanisms underlying neurological disorders. Sequencing studies have identified variation between cohorts to implicate genes in disorders like Tourette syndrome (TS), while neurodegenerative disorders have been modeled in C. elegans, where RNA interference (RNAi) screens have identified regulators of polyglutamine (polyQ) aggregation. Here, I describe an exome sequencing study exploring de novo genetic variation in TS. Implicated genes were assessed for their functional roles and expression and were found to be vital for a variety of cellular processes and had distinct spatiotemporal localization. In a separate project, an ethyl methanesulfonate mutagenesis screen was performed to identify genes that suppress the aggregation of the ataxin-3 protein in which a polyQ expansion causes Machado Joseph disease. C. elegans expressing the human ataxin-3 protein were mutagenized and are currently being characterized.

 Scholarship Sewanee, a campus-wide celebration of student scholarship and creative activity, is made possible by numerous generous benefactors including Walter and Mayna Nance;  The Andrew W. Mellon Foundation;  The Undergraduate Research Advisory Committee; and The Office of the Dean of the College. Production made possible by the efforts of Elizabeth Ellis, Erin Cassell, & Charles McClain;  Physical Plant Services, and Print Services.