Choice Reaction Time

Choice reaction time (CRT) is the latency to select and execute one of several possible responses to one of several possible stimuli. Unlike simple RT, CRT includes a stimulus-response mapping step, so performance reflects both perceptual and decision processes. Hick (1952) and Hyman (1953) showed that CRT increases roughly logarithmically with the number of alternatives, a relationship now known as the Hick-Hyman Law.

Reference: Hick, 1952; Hyman, 1953. The NeuroRank implementation holds the canonical form and scales interference via task-irrelevant stimulus density.

1. Choosing whether to peek, hold, or rotate when footsteps arrive from three possible directions in Valorant.
2. Selecting which of four League of Legends abilities to press when three enemies move into range of different skillshots simultaneously.
3. Deciding whether to reload, swap weapon, or push forward in an Apex Legends final ring fight with incomplete information.

The choice RT phase of the Reaction module presents one of multiple stimuli per trial and requires the matching response. Accuracy is the primary signal: fast but inaccurate choice-RT responses indicate guessing, not genuine discrimination. Accuracy feeds 40% of the Decision Quality dimension.