Date of Graduation


Document Type


Degree Type



Statler College of Engineering and Mineral Resources


Chemical and Biomedical Engineering

Committee Chair

Shuo Wang

Committee Member

Jessica Allen

Committee Member

Xin Li


This research investigates the role that attention and memory plays in visual exploration through a comprehensive analysis of eye movement and behavioral data, alongside incorporation of a computational saliency model. The purpose of this project is to quantify differences in visual attention over repeated viewings of natural scene images by employing a free viewing task that contains a memory component. In Chapter 2, we explore the task’s behavioral data showing that participants generally memorize our images well before we investigate the effect of numerous object and individual feature inclusion. In Chapter 3, we develop four primary methods to quantify visual exploration of our images and implement these methods to determine if differences exist between new and repeated images but also between remembered and forgotten images. We found that these methods showed more intensely focused visual attention in images that had been repeatedly viewed. In Chapter 4, we introduce a computation saliency model adapted from previous works (Wang et al., 2015) and discuss the extensive tuning needed to achieve optimal performance. Further, we explore the differences in saliency weights for new vs repeated images and also 1st vs 2nd vs 3rd image viewings, showing multiple significant differences were observed. In Chapter 5, we incorporate additional methods to determine if our natural scene images were viewed consistently. This included examining fixations in the order of occurrence but also total image consistency. The latter suggested that initial viewings are more similar to tertiary viewing than to secondary viewings albeit this trend is not observed as strongly in images that contain certain semantic features. In Chapter 6, we replicate our previously discussed methods on preliminary data taken from participants with ASD to explore difference in visual attention when compared against controls. Finally in Chapter 7, we discuss key results and conclusions developed by this research before commenting on ways to further alter and enhance the included analyses to provide a more comprehensive analysis of visual exploration.