Student Seminars and Defenses
NSC 503 Seminar
Catalina Guzman - PhD Candidate
Title: TBD
Faculty Evaluators: Ania Majewska & Loisa Bennetto
Student Moderator: Gavin Magill
May 19, 2025 @ 4:00 p.m.
Medical Center | K207
NSC 503 Seminar
Alex Solorzano & Alexis Feidl - PhD Candidates
Titles: TBD
Faculty Evaluators: John Olschowka & Debroah Cory-Slechta
Student Moderator: Margaux Masten
May 12, 2025 @ 4:00 p.m.
Medical Center | K207
NSC 503 Seminar
Alesandra Martin & Emma Strawderman - PhD Candidates
Titles: TBD
Faculty Evaluators: Michael Telias & Frank Garcea
Student Moderator: Jeeyun Kim
May 05, 2025 @ 4:00 p.m.
Medical Center | K207
NSC 503 Seminar
Joanne Chiu & Emma Bryson - PhD Candidates
Titles: TBD
Faculty Evaluators: Jean Bidlack & David Dodell-Feder
Student Moderator: Daulton Myers
Apr 28, 2025 @ 4:00 p.m.
Medical Center | K307
NSC 503 Seminar
Wen Li & Yunshan Cai - PhD Candidates
Titles: TBD
Faculty Evaluators: Rick Libby & Ed Brown
Student Moderator: Mariah Marrero
Apr 21, 2025 @ 4:00 p.m.
Medical Center | K307
NSC 503 Seminar
Tracey Preko & Skylar DeWitt - PhD Candidates
Titles: TBD
Faculty Evaluators: Samuel Norman-Haignere & Ania Busza
Student Moderator: Amelia Hines
Apr 14, 2025 @ 4:00 p.m.
Medical Center | K307
NSC 503 Seminar
Adam Roszczyk & Caleb Mahlen - PhD Candidates
Titles: TBD
Faculty Evaluators: Manoela Fogaca & Andrew Wojtovich
Student Moderator: Tanique McDonald
Apr 07, 2025 @ 4:00 p.m.
Medical Center | K307
NSC 503 Seminar
Gueladouan Jean Setenet & Pavel Rjabtsenkov - PhD Candidates
Titles: TBD
Faculty Evaluators: Thomas O'Connor & Amy Kiernan
Student Moderator: Andrea Campbell
Mar 31, 2025 @ 4:00 p.m.
Medical Center | K307
NSC 503 Seminar
Sean Lydon & Estephanie Balb - PhD Candidates
Titles: TBD
Faculty Evaluators: Benjamin Suarez-Jimenez & Samuel MacKenzie
Student Moderator: Dominic Bunn
Mar 24, 2025 @ 4:00 p.m.
Medical Center | K307
NSC 503 Seminar
Tom Scudder & Lelo Shamambo - PhD Candidates
Titles: TBD
Faculty Evaluators: Doug Portman & Marissa Sobolewski
Student Moderator: Abigail Alpers
Mar 17, 2025 @ 4:00 p.m.
Medical Center | K307
The Impact of Ambient Ultrafine Particulate Matter from Air Pollution on Neurodevelopmental Outcomes in Spiny Mice: A Novel Translatable Animal Model - Thesis Proposal
Margaux C. Masten - PhD Candidate, Neuroscience Graduate Program
There is a growing body of epidemiological evidence linking air pollution (AP) exposure and increased risk for multiple childhood onset neurodevelopmental disorders (NDDs) including attention-deficit hyperactivity disorder (ADHD) and autism spectrum disorder (ASD). Exposure to AP in the third trimester of pregnancy has been linked with higher odds of ASD diagnosis, as well as, more symptoms of inattention and decreased corpus callosum (CC) volume associated with increased hyperactivity. Ultrafine particulate matter (UFP) is one of the most reactive components of AP, due to its large surface area to volume ratio. Furthermore, UFPs present a unique challenge as their small size allow them to penetrate deep into the lungs and traverse many of the body’s barrier mechanisms such as the placenta and the blood brain barrier, creating a unique challenge for the developing brain during gestation. Previous work from our lab in C57BL/6J mice shows that gestational and early postnatal exposures to ambient UFP from traffic related air pollution trigger unique sex-dependent neurobehavioral outcomes, with ventriculomegaly, alterations in myelination of the CC, persistent CC microglial activation, elevated glutamate in the brain, metal dyshomeostasis, and behavioral deficits including impulsivity, cognitive inflexibility, and altered social interaction. However, the sex-difference and directionality of these effects vary between gestational and post-natal exposures. Due to the altricial brain development at birth in traditional laboratory rodents, we do not know if the differences are due to critical windows of exposure or differential routes of exposure. Unlike C57BL/6J mice, the African Spiny mouse (genus Acomys) is born precocial with neural development more similar to humans at the time of birth. This unique model allows us to test the neurotoxicity of air pollution during late gestation with a more translational pattern of brain development. In addition to their precocial brain development at birth, spiny mice are highly social animals allowing for more expanded social behavioral evaluations. The central hypothesis of this thesis is that late gestational UFP exposure induces neurodevelopmental changes in spiny mice similar to the effects seen in postnatal C57BL/6J UFP exposures, including altered white matter development, cognitive inflexibility, and social behavioral deficits.
Experiments from Aim 1 will use transmission electron microscopy to characterize UFP metal contaminants and particle characteristics across maternal cranial nerves, maternal olfactory bulbs, placenta, and the periventricular region of the fetal brain. We hypothesize that inhaled UFP from the dam will translocate across the placenta and into the pup brain and will show differential bioprocessing in the maternal and fetal brains. In Aim 2 we will use electron microscopy and immunohistochemistry to identify changes in myelination and white matter tracts. We hypothesize that exposure in the spiny mice will lead to white matter damage with decreased corpus collosum size, altered myelin ultrastructure, and enlarged lateral ventricles in a male-biased manner. Experiments from Aim 3 will test social interaction and cognitive flexibility using behavioral paradigms including measures of social interaction and communication as well as the translationally relevant ID/ED shift operant task. We predict there will be sex-dependent deficits in social communication and cognitive flexibility in spiny mice exposed to UFP during the late gestational period in utero. Together these experiments will expand our understanding of how late gestational exposure to air pollution confers risk for multiple neurodevelopmental disorders that share sex-biased prevalence rates and behavioral presentations.
Mar 07, 2025 @ 12:00 p.m.
Medical Center | Adolph Lower Aud. (1-7619)
Host: Advisor: Marissa Sobolewski, PhD
"Blind-field visual abilities after occipital stroke: incidence, dynamics, substrates and consequences for visual rehabilitation" - Thesis Defense
Bryan V. Redmond - PhD Candidate, Neuroscience Graduate Program
Cortically induced blindness (CB), which most often results from stroke damage to the primary visual cortex (V1) or its afferents,
leads to binocular loss of conscious visual perception. While motor stroke rehabilitation is well-researched, the visual deficits
faced by CB patients lack effective treatment, with only compensatory therapies like saccadic training and prism lenses
prescribed clinically. CB is considered permanent, offering little hope for visual recovery. However, recent research from the
Huxlin lab and others has challenged this notion, demonstrating the potential for recovering direction discrimination abilities -
among others - within the blind field. In addition, building on the pioneering work of Riddoch and Weiskrantz, Saionz and
colleagues (2020) reported that about 1/3 of naïve, early post-occipital stroke patients retain a range of preserved conscious
simple and complex motion abilities. More rarely, some even retained the ability to discriminate orientation of static targets
within their perimetrically-defined blind fields. Whether with different perimetric tests or psychophysical tasks, evidence is
mounting supporting the heterogeneity of perception inside CB fields. A next step is to identify and understand the natural
history of these abilities, what anatomical structures enable them, and what their presence means for rehabilitation.
The first step in this endeavor is to define the deficit. Humphrey automated perimetry (HAP) is the most common type of clinical
perimetry used in CB. It measures light detection using a small, static stimulus, presented randomly in a grid-like pattern across
the central visual field. However, it does not control fixation during testing as rigorously as the Macular Integrity Assessment
(MAIA) perimeter. We contrasted these two perimeters’ ability to identify visual impairment and assess changes both
spontaneously and following restorative interventions. We concluded that on the sum, HAP performed according to strict test
quality criteria is the most optimal way to quickly but coarsely define the extent and severity of the deficit in CB. Based on HAPdefined
blind-field boundaries, we then proceeded to map motion discrimination in the blind-field. Our standard method for
identifying preservation of such abilities involved repeatedly and densely testing a few, adjacent blind field locations using
random dot stimuli. Although precise, this approach is time-consuming, and oversamples a very small region of visual space
rather than canvassing the entire deficit. This limitation makes it impractical for clinical use, leaving most patients uninformed
about the truly heterogenous nature of their “blind” field.
This thesis addresses this gap, developing an automated, direction discrimination perimetric tool (ADDaPT) able to rapidly and
accurately detect preserved motion discrimination abilities across the HAP-defined blind-field of CB patients. Then, using the
new ADDaPT definition of preservation in concert with computerized, home-based training, we compare the efficacy of training
in preserved and non-preserved CB patients. In addition, we correlated performance outcomes with the progression of
retrograde degeneration affecting the ganglion cell and inner plexiform layers of the retina, measured using optical coherence
tomography at baseline and 12-months post-stroke.
Mar 05, 2025 @ 9:00 a.m.
Eastman Dental Center | EIOH Farash Auditorium (1st floor EDC)
ZOOM LinkHost: Advisor: Krystel R. Huxlin, PhD
NSC 503 Seminar
Stacey Pedraza & Gavin Magill - PhD Candidates
Titles: TBD
Faculty Evaluators: Ed Freedman & Krystel Huxlin
Student Moderator: Catalina Guzman
Mar 03, 2025 @ 4:00 p.m.
Medical Center | K307
NSC 503 Seminar
Nicole Popp & Staci Rocco - PhD Candidates
Titles: TBD
Faculty Evaluators: Nathan Smith & Jennetta Hammond
Student Moderator: Julia Granato
Feb 24, 2025 @ 4:00 p.m.
Medical Center | K307
NSC 503 Seminar
Niki Lam & Leah Sheppard - PhD Candidates
Titles: TBD
Faculty Evaluators: Margot Mayer-Proschel & Anne Luebke
Student Moderator: Thomas Delgado
Feb 17, 2025 @ 4:00 p.m.
Medical Center | K307
NSC 503 Seminar
Aishwarya Jayan & Aaron Huynh - PhD Candidates
Titles: “How do prior expectations influence memory encoding for complex narratives and events?" - Jayan
“Characterizing Upper Extremity Motor Impairments in Ischemic Stroke Patients” - Huynh
Faculty Evaluators: Madalina Tivarus & Lauren Hablitz
Student Moderator: Lia Calcinez Rodruiguez
Feb 10, 2025 @ 4:00 p.m.
Medical Center | K307
NSC 503 Seminar
Aiesha Anchan & Erica Squire - PhD Candidates
Titles: TBD
Faculty Evaluators: Hohui Xia & Gil Rivlis
Student Moderator: Leslie Gonzalez
Feb 03, 2025 @ 4:00 p.m.
Medical Center | K307
When Oscillations Reflect Key Information Needed for Goals: Maintenance Engages Mnemonic Oscillations in Rhesus Monkey - Thesis Defense
Dennis Jung, MS - PhD Candidate, Neuroscience Graduate Program
Working memory (WM) enables temporary maintenance and manipulation of task-relevant information. One important role of WM is preventing information loss during distraction. While neural oscillations are known to support WM maintenance and distractor resistance, less is understood about how anticipation influences these processes. This thesis investigated neural oscillations in WM during distractor anticipation. To test this, we recorded local field potentials (LFP) in the lateral prefrontal cortex (LPFC), a key brain area for WM, and scalp electroencephalograms (EEG) from monkeys performing modified memory-guided saccade (MGS) tasks, with varying in distractor timing and item load. The first experiment tested how distractor anticipation influences brain oscillatory dynamics with fixed distractor timing during memory maintenance. We found widespread thetaband (4-8 Hz) EEG activity better encoded the memory item after, rather than before, the anticipated distractor time, regardless of whether the distractor appeared. However, theta-band LFP activity in the LPFC only encoded the item when the distractor was presented. These results suggest large-scale theta oscillations reflect WM dynamics associated with both maintenance and distractor anticipation, while small-scale theta oscillations in the LPFC specifically encode the stored item, ensuring stability. The second experiment varied distractor timing. We found greater behavioral impairment when the distractor appeared towards the end of the task. EEG theta activity continued encoding item—greater towards the end of maintenance, regardless of the presence of the distractor. Similar encoding was observed for the LFP theta activity only when the distractor was shown. These results suggest WM becomes more vulnerable to distraction over prolonged maintenance, but greater encoding of items may reduce deteriorating distractor effects. The third experiment explored effects of increased item load and internal selective attention on distractor anticipation. Selection increased encoding of an attended item in EEG and LFP theta-band activities. Post-cue distractors tended to increase behavioral errors compared to a single-item conditions in the previous experiments, suggesting increased task complexity and variability impairs distractor anticipation. Together, the results of these experiments demonstrate that the distractor anticipation influences the WM dynamics as reflected in both small- and large-scale oscillatory signals.
Jan 29, 2025 @ 1:00 p.m.
Medical Center | Lower Adolph Aud. (1-7619)
Hybrid EventHost: Advisor: Adam Snyder, PhD
NSC 503 Seminar
Amelia Hines & Sid Chittaranjan - PhD Candidates
Titles: “Potential role of viral latency protein U94A in Alzheimer's Disease" - Hines
“Evaluating the role of calcium dynamics in regulating microglia process dynamics” - Chittaranjan
Faculty Evaluators: Gail Johnson & Sarah McConnell
Student Moderator: Mark Osabutey
Jan 27, 2025 @ 4:00 p.m.
Medical Center | K307
Mitigating Immune-Mediated Cell Loss in Photoreceptor Replacement Therapies: A Preclinical Evaluation Using Advanced Retinal Imaging - Thesis Proposal
Andrea Campbell - PhD Candidate, Neuroscience Graduate Program
Visual impairment affects over 2.2 billion people worldwide, with retinal diseases (RDs) like age-related macular degeneration (AMD) and retinitis pigmentosa (RP) as significant contributors to this impairment. These diseases lead to the degeneration of photoreceptor cells, which lack a natural regenerative capacity in humans. Current treatments primarily aim to slow disease progression, underscoring a critical need for regenerative strategies focused on restoring vision. Photoreceptor precursor cells (PRPCs) derived from human embryonic stem cells (hESCs) and induced pluripotent stem cells (iPSCs) are promising candidates for cell replacement therapies. However, immune-mediated rejection and inflammation remain significant barriers to their success. To address these challenges without relying on prolonged immune suppression, this study evaluates two complementary strategies: (1) short-term systemic immune suppression and (2) co-transplantation of PRPCs with regulatory T cells (T-regs).
Aim 1 evaluates the efficacy of short-term immune suppression in promoting PRPC survival. Prolonged immune suppression increases risks such as infections and systemic toxicity. Inspired by transient protocols in retinal pigment epithelium (RPE) transplantation, this study hypothesizes that a short-term immunosuppressive regimen can promote PRPC survival while minimizing adverse effects. Advanced adaptive optics scanning laser ophthalmoscopy (AOSLO) will facilitate non-invasive, longitudinal imaging of PRPC survival and host immune responses at cellular resolution.
Meeting ID: 944 0302 2429
Passcode: 903589
Aim 2 examines the co-transplantation of PRPCs with T-regs to locally modulate immune responses. T-regs play a key role in immune tolerance and may provide a localized, cellular alternative to pharmacological immune suppression. By dampening inflammation and inhibiting cytotoxic T-cell activity, T-regs could enhance PRPC survival. Using fluorescent reporters and high-resolution imaging, this study will track immune activity, T-reg function, and PRPC survival in real-time, assessing the potential of T-regs to mitigate rejection.
This research integrates cutting-edge imaging technologies, fluorescent reporters, and an NHP model that closely mimics human retinal anatomy, physiology, and immune responses. By leveraging these innovations, the study seeks to advance regenerative therapies for retinal diseases, providing insights into immune modulation and stem cell-based interventions. Success in these strategies could pave the way for safer and more effective treatments for RD patients, addressing an unmet medical need and establishing a framework for future cell-based therapies in ophthalmology.
Jan 13, 2025 @ 11:00 a.m.
Medical Center | K307 (3-6408)
Hybrid EventHost: Advisor: Juliette E. McGregor, Ph.D.