Meet the team!

PRINCIPAL INVESTIGATOR

LINDSAY HALLADAY, PhD

lrhalladay@arizona.edu


Lindsay graduated from Cal State San Bernardino, where she first started researching neural circuits in the developing basal ganglia, in Sanders McDougall's and Cynthia Crawford's labs. She then earned her Ph.D. in behavioral neuroscience from UCLA while working in Tad Blair's lab. Her graduate work investigated the role of neural circuitry underlying defensive action selection. Lindsay then spent four years in metro D.C. as a Postdoctoral Research Fellow in Andrew Holmes's lab at the National Institute on Alcohol Abuse and Alcoholism. Her primary research there examined neural circuitry underlying compulsive alcohol-seeking. Lindsay helped establish the Neuroscience Program at Santa Clara University in the fall of 2017 and received tenure at SCU in the spring of 2023. The Halladay Lab relocated to the University of Arizona's Neuroscience Department in January 2025.  Broadly speaking, the Halladay Lab investigates the neural intersection between reward and aversion. Current research projects aim to identify specific neural circuits mediating allostatic mechanisms related to stress- and/or reward-related behaviors.

UBRP Fellow 2025

Sawyer Sullivan

Hi! I’m majoring in Neuroscience & Cognitive Science, with minors in Studio Art, Spanish, and Information Science. I’m originally from Madison, Wisconsin, so being able to explore Tucson and Arizona has been incredible. I’m interested in the intersections between behavioral neuroscience, cognition, and epigenetics. Outside of the lab, you can find me making all kinds of art, sitting on my friends’ porches, stargazing, or biking around the city.

UBRP Fellow 2026

Jakob Villarreal

Hello! I’m an undergraduate double-majoring in Neuroscience and Cognitive Science and Philosophy, with a minor in Spanish. I’m originally from Chandler, Arizona and have lived in the state my whole life. I joined the Halladay Lab to investigate and understand the neural correlates of behavior, particularly those relevant to psychiatric disorders. Outside of the lab, you can find me out in Tucson with friends, hiking around the state, or making a new Spotify playlist.

Joy Ogbonnaya

UBRP Fellow 2025

Hi! I’m an undergraduate student majoring in Neuroscience and Cognitive Science with a minor in Spanish. I’m a native Arizonan and grew up just two hours north of Tucson in Gilbert, Arizona. I was drawn to the Halladay Lab because of its focus on the neural basis of behavior. I’m excited to contribute to research that bridges cognitive science with real-world topics such as decision-making and emotion. Outside the lab, I enjoy reading, hanging out with friends, and spending time exploring nature.

Marco Estrada

Hello! I am studying Neuroscience & Cognitive Science and Biology, with a minor in Spanish. I was born and raised in the San Francisco Bay Area, where my education fostered in me a love for all things science. I'm especially interested in how experiences can shape the circuitry of the nervous system, which in turn can lead to specific behaviors. I like to spend my free time with family and friends, going on runs, playing spikeball at the U of A mall, cooking new dishes, and trying new cuisine.

Jigisha Rohila

Hey! I’m an undergraduate at the University of Arizona, majoring in Neuroscience and Cognitive Science with a minor in Psychology and Consciousness Studies. I’m originally from India. Before that, I lived in New Jersey, and I definitely miss the cold! I’m particularly interested in neurodevelopmental research, especially how early life stress affects brain development and its connection to neurodevelopmental disorders. Outside of school and lab, I enjoy spending time at lakes, reading, driving around and listening to music.


Kanishk Dravid Anmala

UBRP Fellow 2025

Hi! I am a junior on the pre-med track majoring in neuroscience and cognitive science with minors in biochemistry and philosophy. I was born and raised in Chandler, AZ. I am deeply passionate about research topics such as early life stress, mental health, PTSD, and neuroplasticity — factors that drive my aspirations of becoming both a surgeon and an author. Some fun facts about me are that I was a figure skater for 8 years, I am a boxer, and I love dancing. I spend my free time playing chess, drawing, writing, and working out.

Lab Alumni


Sriparna Majumdar Postoctoral Fellow

Janet Ronquillo '23, De Novo Fellow 2021, DeNardo Science Scholar 2022, NIH postbacc fellow 2023-24

Michael Nguyen '24, De Novo Fellow 2021, Goldwater Scholar 2022, ALZA Science Scholar 2023-24

Varya Zlotnik '24, APA SUPER Fellow 2023, Osberg Fellow 2023

Jennifer Nguyen '21

Sandra Del Toro '24

Sean Do '26, REAL Fellow 2023

Kevin Shimizu '25, REAL Fellow 2023, SURFiN recipient 2024

Kerri Lyons '23, REAL Fellow 2021, DeNovo Fellow 2022

Linnea Rothi '23, DeNardo Science Scholar 2021-23

Matthew Nguyen '21

Jocelyn Yang '24, REAL Fellow 2022

Danny Bui-Tu '22, De Novo Fellow 2021

Avery Curet '22,  De Novo Fellow, 2021

Natalie Rovero '21, DeNardo Senior Prize 2021, REAL fellow 2019

Alex Quan '21, REAL fellow 2019

Max Bjorni '21, DeNardo Science Scholar 2019-21, Barry Goldwater Scholar 2020

Noel Del Toro '21, De Novo Fellow 2019

Bryce Rosellini '21

Hannah Henderson '20,  DeNovo Fellow 2019

Elissa Yang '20

Tasneem Sadok '20

Malia Belnap '19, DeNardo Science Scholar 2018-19

Randi Emmons '19