<p>A pervasive aspect of daily life is searching for a specific target amongst an array of distracting items. Studying such visual searches offers a useful and powerful tool for revealing the underlying aspects of visual attention. Understanding how factors influence accurate target detection serves to both enhance real-world search tasks and inform basic cognitive psychology. The goal of the research presented herein is to examine the effects of expectation, experience, and environment on search behavior. The experiments are conducted in controlled laboratory environments, but are designed to simulate real-world searches, with the express goal of informing the implementation of search tasks in everyday life. First, <italic>expectation </italic>is explored by manipulating target prevalence and measuring the resultant change in behavior as participants' biases shift. Second, <italic>experience </italic>is tested by comparing individuals with and without extensive video game exposure, specifically on their susceptibility to the pressures of rare target search. Lastly,<italic> environment</italic> is examined by utilizing multiple simultaneous targets. This manipulation has been shown to induce errors in radiology, and here the generality of this effect is explored to establish the various pressures to which it is sensitive. Collectively, these data serve to inform how different influences modulate visual search performance, and the results can directly inform the training, recruitment, and execution of real-world search tasks such as those in radiology, cytology, and airport security.</p> / Dissertation