Lab Researchers

Principal Investigator

Percival Matthews
Principal Investigator
http://edpsych.education.wisc.edu/people/faculty-staff/percival-matthews
Curriculum Vitae

My research program is organized around two primary goals: 1) to understand some basic underpinnings of human mathematical cognition, and 2) to find ways to leverage this understanding into effective educational techniques that can be used to impact the life chances of everyday people. My research has spanned all stages of development and has included work both in K-12 schools and in the laboratory. Currently, my largest projects involve

exploring how basic perceptual abilities that all humans come with can help anchor understanding of fractions concepts and
investing how we can improve children’s understanding of the equal sign, a type of knowledge that is an important entry point for algebraic thinking.

When I’m not in research mode, I enjoy hanging out with my wife and two daughters, experiencing new foods, working out, and reveling in the music of the ’70s (which I feel set the high water mark for popular music).

Postdoctoral Researchers

Sangmi Park
Postdoctoral Researcher
Curriculum Vitae

Sangmi is a postdoctoral researcher at UW-Madison. She earned her B.A. in Psychology and M.A. in Child Psychology and Education from Sungkyunkwan University in South Korea, and she earned a Ph.D. in Psychology at Clark University. Her broad research interests includes children’s learning in mathematics. Her most recent research explores how children understand symbolic and non-symbolic fractions and how this relates to their mathematics achievement. Her work aims to provide insights that can help improve children’s math performance.

Lauren Westerberg
Postdoctoral Researcher

Lauren is a postdoctoral researcher at UW-Madison. She earned Ph.D. and M.S. degrees in Human Development and Family Science at Purdue University, and she earned a B.A. in Psychology at Elon University. Her research focuses on the development of STEM knowledge and skills, and relations between STEM and other school readiness domains. Additionally, her work focuses on STEM measure development and evaluation.

Graduate Students

Robert Quintana
Graduate Student

Robert graduated from Gustavus Adolphus College where he earned a B.A. in Psychology. After graduation, Robert worked at an alternative school, where he served as a teaching assistant in a classroom for children with emotional/behavior difficulties. He also worked a Behavioral Technician at Wisconsin’s Early Autism Program and as a math tutor for Schools of Hope in the MMSD school district. In his downtime, he likes to take long walks in areas with vegetation and water, bike around Madison, and work on his jump shot.

Research Interests: Robby is interested in how the development of certain cognitive abilities influence mathematical understanding and trajectories. Specifically, how differences in spatial skill and proportional reasoning influence fraction understanding and general calculation skill. He hopes this research will contribute towards new learning tools and interventions to that make math more accessible and fun.

Xiang Cheng
Graduate Student

Xiang graduated from UW-Madison in May 2024 with a B.S. in Education Studies and Mathematics with certificates in Statistics and Arts & Teaching. She worked as an undergraduate research assistant with the MELD lab for 3 years. She is from Guangzhou, China. In the past, Xiang has been tutoring high school students in mathematics. In her free time, she enjoys writing calligraphy, playing Pipa, singing, and watching cute animal videos.

Research Interests: Xiang is interested in how individuals perform nonsymbolic ratio comparisons across different sensory modalities, particularly with visual and auditory stimuli. She aims to determine whether the ratio processing system is generalized across the broader sensory domain through her research.

Lab Manager

Vedaa Vandavasi
Lab Manager

Vedaa Vandavasi, from Mumbai, India, is a Biological Systems Engineering student at the University of Wisconsin-Madison, specializing in Natural Resources and Environmental Engineering. With experience in atmospheric research, journalism, and sustainability, she is passionate about creating positive environmental impact and aims to advance agricultural technology in developing countries. Vedaa loves reading, traveling, and is always up for a good cup of coffee.

Undergraduate Research Assistants

Maddie Pritz
Undergraduate Research Assistant
Maddie is a second-year undergraduate student at UW-Madison from Grayslake, IL. She is majoring in Psychology, and this is her second semester working in the MELD lab. After finishing her undergraduate degree, she aspires to go to graduate school on the Cognitive Psychology track. Outside of school and the lab, she finds joy in playing the guitar, creating art, and eating good food.

Anna Schellin
Undergraduate Research Assistant
Anna is a second-year undergraduate student from New Prague, MN, majoring in Statistics and Psychology. After finishing her undergraduate degree, she hopes to attend graduate school and continue on a Psychological Statistics path. Outside of her studies, she enjoys hiking, thrifting, and reading.

Madilyn Kaiser
Undergraduate Research Assistant
Madilyn is a senior at UW-Madison from Pulaski, Wisconsin. This is her second semester working in the MELD Lab. She is majoring in Psychology, and hopes to go to graduate school to become a Physician’s Assistant. Outside of school, work, and the lab, Madilyn enjoys traveling, movies, and spending time with friends and family.

Sakeef Sekender
Undergraduate Research Assistant
Sakeef is a first-year undergraduate student from Los Angeles, California majoring in Pre-Business. After graduating, he hopes to get his MBA and work in the business industry, specifically Investment Banking. He really enjoys listening to music, playing basketball and volleyball, and staying active by going on hikes and camping.

Jack Christensen
Research Assistant
Jack is a high school special student with an interest in the effects of psychological, cognitive, emotional, cultural, and social factors on decision-making and learning. This is his first semester in the MELD Lab. He is hoping to deepen his understanding of the relationship between the brain and behavior while being exposed to real-world research practices, including the actual techniques and methodology scientists and professors use to conduct it. Outside the lab, he enjoys curling, fencing, horseback riding, playing Magic the Gathering, and volunteering as an ambassador for JDRF.

Devon Adams
Undergraduate Research Assistant
Devon is a second-year undergraduate majoring in neurobiology on a pre-physician assistant track and working towards a certificate in either global health or gender and women’s studies. Her hometown is Onalaska, WI and some of her hobbies include reading, baking, and spending time with friends and family.

Aster Bi
Undergraduate Research Assistant
Aster is a third-year undergraduate student at UW-Madison from Beijing, China. She is majoring in Statistics. After graduating, she hopes to pursue a master’s degree in the field of either data science or biostatistics. She enjoys singing, doing paint by numbers, and making food.

Graduate Alumni

Yunji Park
Curriculum Vitae

Yunji is a postdoctoral scholar in the department of psychiatry at Stanford University. Yunji completed her Doctorate and a Masters in Educational Psychology at the University of Wisconsin-Madison, and she earned her bachelors degree and a Masters in Cognitive Science in South Korea. Working in the Cognitive Neuroscience Lab, she was involved in the various projects studying the development of numerical cognition. Yunji specifically investigated the representation of magnitude and how it relates to mathematical achievement over the course of the development.

Research Interests: I’m interested in young learners and their brain development in the context of math education. I’m also interested in kids’ structural and functional brain changes shaped by educational experience! My current project focuses on the development of nonsymbolic ratio discrimination and its relationship with math competence (behavioral), children’s neural representations for nonsymbolic and symbolic fractions and how the representation changes over the course of development using fMRI, and exploring white matter tracts that are related with fractional knowledge using DTI. If you are interested in my work and want to know more, please visit my personal web page.

Alex Viegut smiling in red cardigan with black and white shirt underneath.

Alexandria Viegut
Curriculum Vitae

Alex is an assistant professor in the psychology department at UW – Eau Claire. Her current research focus is measuring and supporting students’ understanding of fractions, especially through visual models. She earned Ph.D. (2022) and M.S. (2019) degrees in Educational Psychology at UW-Madison, and holds a B.A. in Psychology from the University of Notre Dame. After completing her PhD, she worked as a postdoctoral researcher in Learning Sciences at the University of Delaware. As a graduate student, Alex enjoyed teaching undergraduate child and adolescent development classes in the Educational Psychology Department.

Research Interests: My work draws from both psychology and math education research, and I’m currently exploring connections between fractions and algebraic thinking. I am also interested in the role of visual representations (number lines, gestures, diagrams, etc.) in children’s math thinking and learning. If you’d like to hear more about my research, please visit my professional website or email me at viegutaa@uwec.edu! Outside of research and teaching, I enjoy running, card games with friends, and playing piano.