The Vision & Cognition Lab

at Johns Hopkins University


Welcome to the Vision & Cognition Lab!

Among other things, we're interested in the limits of visual attention and visual working memory, the psychophysics of numerical estimation, and the interfaces between vision and language. We maintain strong collaborative ties with the Laboratory for Child Development and the Visual Thinking Lab, as well as the larger Vision Sciences Group at JHU.

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Join Us


Justin Halberda, Professor

Dr. Justin Halberda directs the Vision and Cognition lab, and co-directs the Laboratory for Child Development with Dr. Lisa Figenson. He currently holds appointments in the Department of Psychological and Brain Sciences (primary) as well as the Department of Cognitive Science. His recent work in this lab is focused on the organization of visual attention and working memory, psychophysical modeling of the human approximate number system, and the semantics of logical vocabulary (e.g., quantifiers).

Curriculum Vitae
231 Ames Hall

Current Students

Emily is a graduate student who has been working with Dr. Halberda since the fall of 2017. She is interested in studying magnitude systems and the visual number sense using computational models. Prior to graduate school, Emily studied psychology, math, and classical languages at Macalester College.


Emily Sanford

Qian Yu

Qian joined the lab in 2017 and has been working with Dr. Halberda on questions related to the mechanisms underlying visual working memory. Her work on this topic has seen her maintain active collaborations with Dr. Firestone and Dr. Flombaum. Before arriving at JHU, Qian translated popular books (including Steve Jobs by Walter Isaacson!) and also worked in Ying-Yi Hong's Culture Lab at the Chinese University of Hong Kong where she explored the Uncanny Valley phenomenon.


Caroline is a first year graduate student working with Dr. Halberda and Dr. Firestone. Caroline is interested in the relation between attention and experience, including how attentional capacities develop from childhood through adolescence and into adulthood. She spent her undergraduate and MA years at NYU in Marisa Carrasco's lab investigating performance field asymmetries and links between vision and touch.


Caroline Myers

Nick Bisbee

Nick is a first year graduate student working with Dr. Halberda and Dr. Feigenson. He is interested in the structure of objects, part/whole relationships, and the development of number. Prior to graduate school, Nick studied neurobiology and behavioral neuroscience at UT Austin then spent several years teaching high-school physics (partly in collaboration with UT Austin).


Postdoctoral Fellows

Nicolò Cesana Arlotti

Originally from Milan, Italy, Nicolò received his PhD in 2016 under Luca Bonatti at Universitat Pompau Fabra in Barcelona, Spain. He joined the Vision Lab in 2018 where he has continued his work on exploring the precursors of logical reasoning in infants.


VCL Alumni

Pat joined the lab in 2018, having studied applied math and cognitive science as an undergrad here at JHU. He was the lab manager for the VCL and for Prof. Chaz Firestone's Perception and Mind Lab until 2020, when he left to pursue a PhD in cognition and perception at New York University.

Pat Little

Josh Langfus

Josh graduated from Johns Hopkins in 2015 with undergraduate degrees in Cognitive Science and Philosophy. Before working in the VCL, Josh spent a year in Madrid, Spain teaching English to high school students as part of a Fulbright grant. His interests include computational models, use of technology as a vehicle for cognitive interventions, and the structure of concepts. He served as lab manager from 2016 until 2018 when he left the lab to pursue a PhD in clinical psychology at the University of North Carolina, Chapel Hill.


Tyler graduated from Johns Hopkins in 2015 with a B.A. in Cognitive Science and served as the Lab Manager from 2014 to 2016. Currently, he's pursuing his PhD in Linguistics at University of Maryland, College Park and is interested in psycholinguistics, semantics, and language acquisition. Check out his Personal Website

Tyler Knowlton

Hrag Pailian

Hrag defended his dissertation, "Costs of Manipulating Information in Visual Working Memory" in July 2015. In it, he focused on the following questions: is the limit for manipulating information independent of that for storing information and are original representations updated or do they remain separate once they have been subjected to a given computation? To this end, he has developed a novel method - the Flicker paradigm - which allows for storage constraints to be studied within the context of how VWM is flexibly used in the real world. He is currently a Postdoctoral fellow under George Alvarez in Harvard's Vision Sciences Laboratory. Check out his Personal Website

Dr. Darko Odic was a graduate student in the lab from 2009 to 2014. He defended his dissertation, "Objects and Substances in Vision, Language, and Development", in 2014. He's currently an Assistant Professor in the Department of Psychology at the University of British Columbia, where he is the PI of the Centre for Cognitive Development. Check out his Personal Website

Darko Odic

Hee Yeon Im

Dr. Hee Yeon Im defended her dissertation, "An exploration of ensemble visual processing through perception, attention, and memory", in 2013. Since then, she has worked as a Postdoctoral fellow in the Song lab at Brown University and is currently a Postdoctoral fellow in the Kveraga Lab at Harvard Medical School.

Dr. Melissa Libertus was a Postdoctoral fellow in the lab from 2010-2013. Currently, she is an Assistant Professor in the Psychology department at University of Pittsburgh, where she directs the Kids' Thinking Lab. Check out her Lab Website

Melissa Libertus

Robert Eisinger

Robert graduated from Johns Hopkins in 2013 with a B.S. in Computer Science and fearlessly managed the lab for 3 years. He is currently pursuing a joint MD/Ph.D. at the University of Flordia College of Medicine.

Ryan graduated from Johns Hopkins with a B.A. in Neuroscience and an M.S.E. in Computer Science and served as the lab's inaugural manager. He is now pursuing a Ph.D. in Neuroscience at Princeton University.

Ryan Ly

☞ And countless undergraduate research assistants, programmers, and collaborators who've contributed to our success over the years! ☜