A fresh look at task structure: exploring set size, stimulus-response properties, attention, and conflict through transitional analysis

How do our brains process and store information about our behaviors? When using a TV’s remote control, you probably don’t think about each button and what it does. Instead, you likely consider groups of related controls. Some change volume, others control playback, some navigate menus. These groupings simplify our thinking about actions and are therefore crucial for effective behavior. Yet, we know little about how these structures are formed. This dissertation 1) explores which factors induce cognitive structures and 2) develops novel tools to measure them. Specifically, I compute the duration of each possible sequence of responses to visualize how they are related. First, I asked how the number of stimulus-response pairs (e.g., buttons on a remote) influenced subdivision. I presented four or eight targets and structure increased with additional items. Next, I explored how stimulus properties and method of responding might change structure. Suppose you used a remote with two hands instead of one or that buttons were color-coded according to their function. Participants responding to distinct sets of targets used more structure compared to those that saw one set, but method of responding did not impact cognitive structures. Finally, some stimuli require different actions depending on the context. How might this change the organizational principles above? To answer this question, I asked participants to shift between task-relevant properties depending on a cue (e.g., respond to target color or shape). Results revealed that stimulus, response, and spatial factors all interact to determine the cognitive organization of our behaviors.