I work with Dr. Michele Rucci in the Active Perception Laboratory at the University of Rochester where the overarching theme of my research is understanding vision as an active process by investigating the crucial interaction between visual perception and oculomotor behavior. This research integrates experimental and theoretical approaches to characterize realistic inputs to the retina during the acquisition of fine spatial details, to understand how vision changes as a result of these behaviors, and to elucidate the neural mechanisms underlying human visual perception.
Humans execute microsaccades (pink) and ocular drift (green) while reading the 20/20 line of an eye chart.
The human eye has only a tiny region dedicated to high-acuity vision known as the fovea. The smallest eye movements, such as microsaccades and ocular drift, drastically change the image impinging on the fovea. Despite its critical importance for seeing fine details, visual function within the fovea is vastly understudied. My research investigates how small eye movements impact visual acuity and the time course of vision within the fovea.
A brief summary of how saccades transform visual space into a spatiotemporal flow impinging on the retina.
Human vision is unlike a camera, which can capture rich information about the world in a single stationary snapshot. In reality, our eyes are always moving so that we capture not a snapshot of the world, but a movie. Contrary to common intuition, a moving image is actually beneficial for vision -- even when examining fine details. My research aims to understand how the continually-changing visual flow impinging on the eye encodes spatial information in temporal signals, and how the visual system uses these signals to form a percept of the world.
Pattern of activity in an array of modeled P ganglion cells exposed to a 20/20 line E during ocular drift. Levels of simulated activity are color-coded so that red and blue represent high and low responses, respectively. Note that the smaller drift measured in the Snellen test enhances the relevant edges of the optotype.
Microsaccades and ocular drift have traditionally been believed to be noise in the oculomotor system. However, given their critical roles in precisely positioning visual targets within the fovea and structuring the visual flow entering the eye, the question arises of whether we can control them to maximally benefit from the interaction of the spatial and temporal properties of the eye. Ongoing research in the lab examines the level of control that humans exercise over their smallest eye movements and how changes in oculomotobehavior impact visual perception.
Binocular Vision and Depth Perception
Though the two eyes are generally looking in the same direction, the images entering the eyes are moving independently from each other most of the time. How can high acuity or even fine depth perception be achieved in the presence of such uncorrelated motion? My current research investigates the consequences of binocular oculomotor behaviors to the perception of 2 and 3-dimensional patterns.
Eye movements recorded simultaneously from both eyes as subject read the 20/20 line of an eye chart.