The Fisher Fellows in Neurosceince

Graduate student in the laboratory of A. James Hudspeth, MD, PhD

Emily Atlas successfully defended her Ph.D. in September 2025. Her research focuses on understanding how organs like the ear develop with a high level of precision. This is an important question because the intricate structure of the ear is required for its proper function. When sound waves enter our ear, they physically push on specialized cells that then get excited and signal their activation to the brain. Because these sensory cells are physically stimulated by sound waves, they need to be positioned properly within the tissues of the ear to function correctly.

To explore these mechanisms in a tractable system, Dr. Atlas turned to the model system of zebra fish, which have sensory organs embedded on the surface of their skin that contain cells very similar to the ones in human ears. The fish use these organs to sense water flows and thus escape predation, align with currents and school with other fish. Importantly, since these organs are on the surface of fish, it is possible to acquire long, high-resolution 3D videos of their development.

Dr. Atlas optimized imaging protocols and data analysis pipelines so that she can study cell movements and structure as sensory cells position themselves and interact with their neighbors. She also optimized protocols in the lab to generate mutants using CRISPR-Cas9 and to assess gene expression changes as cells develop. These protocols will ultimately help to understand the machinery that cells use to interact with each other and to move around to create a tissue that functions properly, and to explain how cells use potentially basic, simple rules and work together to generate complex structures.

Over the last year, Dr. Atlas focused on understanding how hair cells of the zebra fish’s lateral line, a sensory system that detects water movement instead of sound, develop and polarize precisely. In the lateral line, hair cells form in pairs. Once mature, one cell detects water flowing from the head, while its sister detects flow from the tail. Dr. Atlas’s research investigates how these two cells become oriented in opposite directions and position themselves within the organ to create a mirror-symmetric pattern.

In particular, Dr. Atlas characterized the roles of specific genes, identified through single-cell RNA sequencing, that act downstream of early fate decisions to establish hair-cell polarity throughout maturation. This work aims to shed light on the cellular mechanisms that govern hair cell development, cell polarity, and the precise coordination of cell behavior, integrating insights from genetic and molecular approaches and physical understanding. In addition to continuing this experimental work, she has been writing up these results for publication. Dr. Atlas is deeply grateful for the support of the Fisher Foundation Fellowship, which has enabled her to pursue this research.

Graduate student in the laboratory of Nathaniel Heintz, PhD

Matthew Baffuto’s research focuses on DNA modifications that occur in specific cell types during normal human aging and in neurodegeneration. By examining postmortem human brain tissue, he can profile various types of molecular changes and give insight to what is happening in healthy and abnormal cells.

Over the past year, Mr. Baffuto’s research has expanded to characterize functional epigenetic signatures within regulatory regions across various regions of the human brain, including basal ganglia, cerebral cortex, cerebellar cortex, and hippocampus. He has identified specific druggable targets that are dysregulated in neurodegenerative diseases as well as those that modulate the activation state of these regions.

Mr. Baffuto’s current work also focuses on identifying isoforms of these proteins expressed in dysregulated neuronal cell types, assessing their activity in model systems, and leveraging AI-based docking tools and patented compounds to evaluate binding specificity for target isoforms. Additionally, he has submitted a manuscript on some of these findings that is currently in the review stage for publication.

Graduate student in the laboratory of Alipasha Vaziri, PhD

Kevin Barber primarily focuses on establishing a training and behavioral analysis pipeline that will serve as the basis of his investigation into the neural mechanisms underlying decision-making.

To do this, Mr. Barber studies how the brain forms choices by studying mice engaged in a carefully designed decision-making task. Using cutting-edge imaging technology, he and his collaborators can observe the activity of tens of thousands of neurons simultaneously while mice report decisions that are guided by visual stimuli. A key advancement has been the ability to distinguish between two fundamental types of neurons: excitatory neurons that transmit signals and inhibitory neurons that suppress them. This distinction has provided crucial insights into how neural circuits balance competing signals during goal-directed behavior. By applying statistical methods that reveal hidden patterns in complex neural data, Mr. Barber and his colleagues uncovered the mechanism by which excitatory and inhibitory populations work together to transform sensory information into accurate choices.

More recently, they have been investigating how longer timescale brain states are represented across large populations of neurons during the task. Mr. Barber and his team seek to reveal how states such as engagement, disengagement, or bias are encoded in collective neural activity and shape how individual decisions unfold. By tracking brain state representations alongside moment-to-moment neural activity, they can now predict with remarkable precision a mouse’s decision accuracy, even before any visual stimulus is presented. This finding demonstrates that large-scale neural recordings can capture not just immediate task-relevant information, but also the broader contextual states that influence behavior. Mr. Barber’s hope is that understanding how these states are represented across neural populations could provide important insights into attention, learning, and disorders that affect decision-making.

Mr. Barber is hopeful that this project will expand our understanding of a fundamental cognitive process and potentially provide a new perspective on how correct and incorrect choices are formed in the brain.

MD-PhD student in the laboratory of Sidney Strickland, PhD

Lauren Sweetland-Martin in 2025 completed her PhD studies and returned to medical school to continue her training as part of the Tri-Institutional MD-PhD program at Weill Cornell Medical College, Memorial Sloan Kettering Cancer Center, and The Rockefeller University. She investigates how certain dietary fats may protect the brain from amyloid-beta buildup. Her preliminary work suggests a protective effect of a high-fat diet when fed to mice affected by Alzheimer’s disease before onset of pathology.

Ms. Sweetland-Martin is planning additional experiments to validate whether this effect can be observed in other mouse lines, such as one with mutations affecting the amyloid precursor protein. She and her colleagues will also explore whether a high fat diet affects the vascular microenvironment in the mice brains and test various configurations of dietary fats and other compounds to determine if there is an optimal diet for neuroprotection.

A student in the Tri-Institutional MD-PhD Program, Ms. Sweetland-Martin has completed her initial medical training at Weill Cornell Medical College and conducted doctoral research at The Rockefeller University under the mentorship of Dr. Sidney Strickland and Dr. Erin Norris. Her PhD work investigated the effects of an early lipid-rich diet on the amelioration of Alzheimer’s disease pathology and cognitive decline. As a future physician-scientist, Ms. Sweetland-Martin is dedicated to working with the geriatric population to further scientific knowledge and improve patient care and outcomes for neurodegenerative diseases. She is grateful for the opportunities provided by the Fisher Center for Alzheimer’s Research Foundation and is eager to continue her research career investigating Alzheimer’s disease, dementia, and the pathology of aging.

Graduate student in the laboratory of Nathaniel Heintz, PhD

Ester Siantoputri is examining the molecular changes that occur in the human hippocampus during early-stage Alzheimer’s disease. The hippocampus is a region of the brain that is critical for memory and spatial cognition, and it consists of various neuronal subtypes that are differentially affected as the disease progresses. By comparing vulnerable and resistant cell types, Ms. Siantoputri may be able to find molecular targets to protect neurons against Alzheimer’s pathology.

A subtype of neurons in the hippocampus, the CA1 pyramidal neurons, is affected early in Alzheimer’s disease. Ms. Siantoputri’s research aims to uncover the mechanisms behind this selective vulnerability using a technique called Fluorescent Activated Nuclear Sorting (FANS) followed by deep molecular profiling on postmortem human brain samples. She has generated molecular profiles from a cohort of healthy and early Alzheimer’s donors and gleaned some insights. In the neurons, there is a significant loss of RELN, a molecular signal that is crucial to the activation of learning and memory pathways. This loss may affect CA1 neurons specifically, as they express an adaptor, DAB1, which works together with RELN to relay this information. Ms. Siantoputri and her collaborators hypothesize that this may be a critical factor underlying selective vulnerability in CA1 neurons. Targeting this pathway may be the key to a more effective therapeutic strategy for early Alzheimer’s patients. Ms. Siantoputri is currently working to validate this result and publish it in a scientific journal.

Ms. Siantoputri spent her childhood in Indonesia before moving to Singapore at the age of 15 to further her education. Her father’s battle with neurodegenerative disease piqued an interest in the subject, leading her to shift into neuroscience research despite obtaining an undergraduate degree in biomedical engineering. When she started in the graduate program at Rockefeller, she rotated in various Alzheimer’s disease labs and became increasingly fascinated by the field. This led to her current project, studying the molecular changes that cause selective cellular vulnerability in Alzheimer’s disease. Ms. Siantoputri aspires to enhance our understanding of the disease and contribute to the ongoing search for effective therapeutic strategies.

In addition to her research, Ms. Siantoputri dedicates time to volunteering for outreach initiatives that aim to make science education more accessible to underrepresented communities. She has volunteered with the Summer Neuroscience Program, teaching a small group of high school students how to read a research paper and conduct their own experiments. She is also an event director for Rockefeller Inclusive Science Initiative, planning social and volunteering events to engage the campus community and enrich their experience at Rockefeller. In her free time, she enjoys drawing, painting, and taking long walks around the city.

Graduate student in the laboratory of Cori Bargmann, PhD

Jinghong Tang grew up in Hefei, China, and came to the U.S. in 2017 to study at the University of Rochester, where he double-majored in cell and developmental biology and economics. His undergraduate research focused on how developmental growth of the fruit fly is regulated.

At Rockefeller, Mr. Tang has pivoted to neuroscience, drawn by how much remains unknown about the brain. He studies the fundamental principles of how neurons—the brain’s basic building blocks—operate at the cellular level. His thesis proposal is entitled, “Dissecting the Molecular and Cellular Basis of Neuropeptidergic Control of Behavior in C. elegans.”

Mr. Tang investigates how neurons talk using tiny chemical messages called neuropeptides. These messages can travel short or long distances and act within seconds to hours, helping adjust brain activity and guide everyday functions such as eating and handling stress, as well as modulating mood, social behavior, and alertness. Dysfunction in peptide signaling has been linked to conditions like Alzheimer’s disease, Parkinson’s disease, and migraines.

Mr. Tang uses the nematode worm Caenorhabditis elegans as a model and is developing methods to label and visualize these peptides using high-resolution microscopy. This allows him to measure adjustments in peptide production and understand how that changes behavior. In addition, he is building sensors that allow him to monitor neuropeptides as they are sent and received in real time, in live worms, and linking these signals to specific behaviors. James hopes this research can uncover the fundamental cell biology of neuropeptides to provide a deeper understanding of their roles in disease and the search for cures.

Outside of research, Mr. Tang participates in the Tri-I Mentorship Initiative (TIMI), helping college students apply to graduate school and offering career advice to high school students. His other interests include history, archaeology, and space exploration.

Graduate student in the laboratory of Vanessa Ruta, PhD

Jiaqi Wang completed her undergraduate studies at Peking University, where she majored in biological sciences and graduated summa cum laude. Trained as a molecular neuroscientist, she came to The Rockefeller University with a passion for understanding brain functions and enthusiasm for investigating neural basis of natural behaviors. She joined Dr. Ruta’s lab to study the courtship behavior of fruit flies.

Social animals navigating a complex environment are constantly integrating current sensory inputs with past experience to select actions that best serve their survival needs. In ever-changing environments where sensory information is often intermittent, animals rely on memory to bridge gaps in sensory input and guide behavior effectively.

Fascinated by the rich repertoire of courtship rituals in fruit fly Drosophila melanogaster, Ms. Wang is actively investigating how males alternate between sensory-guided versus memory-guided behaviors during courtship towards females. Her research seeks to discover how insect brains are innately hard-wired to adapt to dynamic sensory environments by flexibly switching between different behavioral strategies, offering insight into animals that may have evolved shared behavioral and neural solutions to common challenges during social interactions. Her thesis proposal is entitled, “Uncovering the role of spatial memory for conspecifics in courtship behavior of Drosophila melanogaster.”

Outside of the lab, Ms. Wang finds inspiration in art, music, and sports, pursuing her passions as an amateur violinist and rock climber.