Dr Emma Stewart

Research

visual perception, eye movements, object and shape perception, peripheral vision, visual prediction, visual inference

Interests

My research broadly investigates how humans perceive the visual world and make eye-movements to guide decisions and actions. I combine behavioural and psychophysical methods with eye-tracking, computational modelling, reaching, computer graphics, and statistical modelling to investigate the following topics:

1) Oculomotor planning. When we need information about something in our environment, we make rapid eye movements (saccades) to bring objects or areas of interest into our high-resolution central vision. How does this planning happen, and what sort of factors (visual, environmental, internal) determine when and where we direct our gaze?

2) Peripheral vs central vision. We make eye movements 2-3 times every second, but maintain a stable percept of the world, despite a constant change of visual input on the retina. How does the brain achieve this, and how is our experience of the world shaped by both peripheral and central vision?

3) Perceptual inference. Humans can make rapid inferences based on the physical properties (i.e. shape, geometry) of objects in the world. How do we make such inferences, and how do they affect motor planning, metacognition, and decision-making?

4) Past experience. Humans build priors about how things in the world will act, based on a lifetime of visual experience. How do these priors shape perception, action, and oculomotor planning?

5) Object viewpoint perception. Objects look different depending on how they are situated relative to you. How can we use non-uniformities in object viewpoint perception to inform us about the nature and dimensionality of our inner world, our mind’s eye?

6) Physical understanding and oculomotor control. How does our physical understanding of the world affect our interactions with the world via eye movements, and what is the interconnection between our mental models of the world and oculomotor control?

**Biography**
After completing undergraduate degrees in Psychology, Law, and French, I completed my PhD in Psychology at The University of Adelaide in Australia, under the supervision of Prof Anna Ma-Wyatt. For my PhD work, I investigated how visual perception changes when humans make eye and hand movements. I then moved to Germany in 2016 to do a post-doc with Prof Alexander Schutz at the University of Marburg, where my research focussed on how humans maintain the percept of a stable world, despite making 2-3 eye movements every second. In 2021 was awarded a grant from the German research council (DFG) to work with Prof Roland Fleming at JLU Giessen (Germany), where I led my own research program looking at how inferences from the physical properties of objects in the world influence eye movements. In December 2023 I joined Queen Mary as a Lecturer (equiv. Asst. Prof) in Psychology.

Publications

2024

2023

2022

2020

2019

2018

2017

2015