Projects

Go and Nogo Decision Making

The decision to make or withhold a saccade has been studied extensively using a go-nogo paradigm, but little is known about the decision process underlying pursuit of moving objects. Prevailing models describe pursuit as a feedback system that responds reactively to a moving stimulus. However, situations often arise in which it is disadvantageous to pursue, and humans can decide not to pursue an object just because it moves. This project explores mechanisms underlying the decision to pursue or maintain fixation. Our paradigm, ocular baseball, involves a target that moves from the periphery…

Integration and Segregation

Traditionally, smooth pursuit research has explored how eye movements are generated to follow small, isolated targets that fit within the fovea. Objects in a natural scene, however, are often larger and extend to peripheral retina. They also have components that move in different directions or at different speeds (e.g., wings, legs). To generate a single velocity command for smooth pursuit, motion information from the components must be integrated. Simultaneously, it may be necessary to attend to features of the object while pursuing it.

Fixational and Functional PRL in Central Vision Loss

Individuals with central vision loss (commonly due to age-related macular degeneration), must use viewing strategies using peripheral vision. Patients often adopt a preferred retinal locus (PRL) for visually guided behavior. While the are clinical measures for estimating the PRL, little is known about use in the real world. Our research seeks to characterize this natural behavior and inform visual rehabilation techniques.