Peter J. Marshall

I am a developmental scientist interested in how new forms of action, perception, and understanding emerge over development. Much of my work asks how infants come to act in increasingly organized ways, and how changes in behavior relate to changes in the developing brain and body.

My research spans developmental psychology, cognitive neuroscience, and developmental theory. Current work focuses on infant reaching and grasping, the development of neural representations of the body, and new ways of characterizing developmental change from naturalistic behavior. A more recent strand of my work examines children's interactions with emerging technologies, including social robots and AI-generated content.

Across this work, I am interested in what changes when development is treated as part of the explanation rather than simply as something to be measured. My theoretical work has examined what it means to understand the brain as part of an active, developing organism rather than as an isolated system, and how psychological capacities take form through histories of activity and interaction.

I studied Natural Sciences at the University of Cambridge, specializing in zoology, and went on to complete a Ph.D. there with a research focus in developmental psychology. I then joined the Department of Human Development at the University of Maryland as a postdoctoral researcher and later as a Research Assistant Professor, where my work focused on temperament, attachment, early experience, and brain development.

I joined Temple University in Philadelphia in 2004 and am now Professor of Psychology and Neuroscience. From 2016 to 2026, I served as Chair of the Department.