(photo of JHU's Peabody Library, where we wish we held our lab meetings)

The PERCEPTION & MIND LAB investigates how we see, how we think, and especially how seeing and thinking interact to produce sophisticated behavior. We are located in the Department of Psychological and Brain Sciences at Johns Hopkins University, and we are also affiliated with the cross-departmental Vision Sciences Group. This page contains information about who we are and what we do.



Principal Investigator

Chaz Firestone (personal homepage)
Assistant Professor of Psychological and Brain Sciences

Chaz comes to Hopkins after having done his graduate work in the Department of Psychology at Yale. Before that, he spent some time as a graduate student in philosophy at Brown, where he was also an undergraduate. When he's not trying to figure out how seeing and thinking relate to one another, Chaz likes to grapple, eat ceviche, and set spurious world records for fastest circumnavigation of the globe on foot.

Graduate Students

Chenxiao Guan
Graduate Student (co-advised by Jonathan Flombaum)

Chenxiao is interested in connections between perception and action, including how we perceive objects that can interact with us (e.g., graspable tools) and with each other (e.g., jigsaw puzzle pieces). She comes to us from the University of Rochester, where she explored neural representations of affordances in the CAOs Lab with Brad Mahon, and took advanced math courses for fun. Chenxiao is also a skilled driver of ATVs, and is rumored to be in a band.

Zekun Sun
Graduate Student

Zekun is curious about the 'intelligence' of visual perception, and wants to know how much of our rich experience of the world is explained by perception vs. by cognition. Her previous work at the Chinese Academy of Sciences explored visual attention to painful images (such as a hammer hitting a hand), including one study in which she inflicted actual pain on her subjects by attaching a contact-heat thermode to their arms. For this reason, we don't mess with Zekun.

Graduate Affiliates

Qian Yu
Graduate Student in the Bedny and Halberda labs

Qian is interested in the mental representation of magnitudes. While working as a translator of popular books (incl. Steve Jobs by Walter Isaacson!), she translated some psychology books and became fascinated by research on how the mind works. So, she joined Ying-Yi Hong's Culture Lab at the Chinese University of Hong Kong and explored aspects of the Uncanny Valley phenomenon. With Qian, you get two lab members for the price of one, since she is rarely seen without her cat, Pipi.

Lab Manager

Jose Rivera-Aparicio
Lab Manager

Jose is interested in the relationship between linguistic and perceptual categorization. He once walked up to Chaz after a talk with a fantastic resume and even better questions, so Chaz responded by offering him a job. Jose's previous work in Mariko Moher's Early Childhood Cognition Lab at Williams College explored how children and adults prioritize different features (such as color vs. shape) in sorting objects; now Jose sorts things here in the lab.


Patrick Little
Research Assistant

Pat is a rising junior studying applied math and cognitive science. In the lab, he's exploring how very tiny fluctuations in behavioral responses can answer very big questions about how perception works. Pat has an unusual talent for listening: He is a member of the peer listening group A Place To Talk, and he subscribes to more podcasts than Chaz has heard of. He also likes watching gourmet cooking shows, and then applying this knowledge to his other pastime: microwaving burritos.

J.J. Valenti
Research Assistant

J.J. is a rising senior at JHU studying cognitive science and philosophy. Here in the lab, he is excited to conduct a project on physical reasoning for which he won a Provost's Research Award — technically earning the lab its first ever 'grant'! J.J. is also involved in the PILOT program, as well as the Prometheus Undergraduate Philosophy Journal. When not on campus, he enjoys exploring Baltimore with his "posse" (J.J.'s word), or spending a quieter night in with an online lecture.


We have recently collaborated with the following researchers:

Perception is how we make contact with the world around us. How does this core process interface with the rest of the mind?

Our lab approaches this and other questions using the tools of vision science. Much of our work uses computer-based psychophysical experimentation, but we also explore these questions using larger real-world environments, computational models, 3D-printed stimuli, studies of brain-damaged patients, and even some unusual 'field work' (including experiments run in New York City's Times Square!).

A central research interest in the lab is how perception is 'smarter' and richer than we often give it credit for, often influencing — or even incorporating — surprisingly sophisticated processing that you might typically associate with higher-level cognition. For example, we've recently become interested in how our minds generate physical intuitions about the world (e.g., how we determine that a pile of rocks will topple over or stay upright). In one recent project, we have explored how basic representations of an object's shape can reach all the way up to our higher-level judgments about how that object will behave in physically rich scenarios, creating illusions of balance whereby objects that look hopelessly unstable may in fact balance perfectly (or vice versa).

We have also engaged with core questions about the underlying 'format' of what we see. Just as the format of a digital file constrains how it can be used (consider how a .doc file is useful for different purposes than a .pdf), the way our minds encode and represent information constrains how that information can be used by other processes. We have explored the format of perceptual representations by taking objects and shapes as a case study. Using new paradigms the lab has developed, we have found surprisingly direct evidence that the mind represents objects much as an architect might represent a building — in the format of a 'blueprint' or 'skeleton' that explains why objects look and behave as they do.

The lab also has a deep interest in foundational questions about the nature of perception. In particular, we have explored the ways in which higher-level factors such as language, desire, emotion, and action can — and cannot — influence what we see. Our work on this long-standing question in cognitive science has suggested that vision is not simply another kind of cognition, but rather is a truly distinct, 'encapsulated' process in the mind.

For a list of lab publications, see here.


Some of our recent work explores illusions of balance.

Click this shape, anywhere you like!

What can art history tell us about seeing and thinking? Find out here.

Join Us

We are actively recruiting a postdoctoral fellow! There are also opportunities for undergraduate research assistants. If you're interested in joining the lab, please send an e-mail to Chaz Firestone. Please also check out our opportunities page to learn more about the positions currently available in the lab.