This is an exploratory study. We do not have strong a priori hypotheses, and the purpose of the study is not to generalize beyond the study sample. We are merely interested in mapping out the movement of attention as a subject navigates through a busy, interactive space. We predict perhaps that probes near the player will be noticed more often than probes far away, and that probes in front of the player will be noticed more often than probes behind the player. However, there are many aspects to explore, including the effect of the player's movement between probe spawn and probe detection. As such, we will analyze the data in several ways and explore multiple potential hypotheses. These analyses include: * examining reaction time and detection rates for near versus far probes * examining reaction time and detection rates for in front versus behind probes * creating a "heatmap" on the play area of detection and reaction time as a function of location of presentation and position at probe spawn and probe detection * Examining the interaction between a probe's near/far status, in front/behind status, and vertical height as it relates to detection and reaction time * Examining the effect of a player's movement between spawn and despawn on detection and reaction time * looking for block-level effects on detection rates or reaction time