One of two boxes will light up. Press the matching side - โ Left key or โ Right key (or tap the box). 10-trial average. Choice RT is ~60ms slower than simple RT.
Hick's Law (1952) states that reaction time increases logarithmically with the number of choices. Two choices adds ~50-70ms over simple reaction time. This "decision time" reflects how quickly the brain can discriminate between stimuli and select the correct response. Choice reaction is a more demanding human benchmark than simple reaction tests.
Compare with your Simple Reaction Time. The difference reveals your personal decision-making overhead.
Choice reaction time is a more demanding human benchmark than simple reaction tests โ it's what actually matters in real-world split-second decisions.
Choice Reaction Time (CRT) extends simple reaction time by requiring a decision between stimuli. The task - two lights, press the matching side - introduces a stimulus-identification step that adds approximately 50โ80ms to your response time compared to simple RT. This difference, the decision time component, is predicted by Hick's Law (1952): reaction time increases logarithmically with the number of choices. Two alternatives add roughly one "bit" of information, and each additional bit costs approximately 150ms.
Hick's Law has profound implications for product design, aviation, and combat - situations where the number of available choices determines response speed under pressure. Fighter pilots are trained to minimize decisions under combat conditions precisely because each additional option adds cognitive processing time. UI designers use Hick's Law to limit menu options and reduce user response time. Understanding your personal Hick's Law coefficient - how much each additional choice costs you - is a meaningful index of decision-making efficiency.
Compare your CRT score with your Simple RT score to isolate your personal decision-time overhead. If the difference exceeds 100ms, stimulus discrimination (identifying left vs right quickly) may be slower than your detection speed - suggesting that spatial processing or response selection is your bottleneck rather than neural conduction speed. If the difference is under 50ms, you are especially efficient at integrating the detection and decision steps.
Average CRT on our platform is approximately 360โ400ms. The global average for simple RT is ~284ms, giving a typical decision overhead of 80โ120ms. Athletes in reactive sports (tennis, cricket, boxing) show smaller-than-average decision overhead, reflecting practice at rapid stimulus-response translation.
Average CRT on this platform is approximately 360-400ms. Scores that keep decision overhead over simple reaction time under 50ms represent especially efficient stimulus-response integration.
Choice reaction adds a stimulus-identification and decision step on top of pure detection, which Hick's Law explains as reaction time increasing logarithmically with the number of possible choices.
Hick's Law, established in 1952, states that reaction time increases logarithmically with the number of choices available, with each additional bit of information costing roughly 150ms of response time.
The test typically presents a small number of choices (such as two directions or sides), which keeps decision complexity low while still requiring genuine discrimination between stimuli.
It's one factor researchers study in driving safety research, since quickly identifying and responding to the correct stimulus among several options mirrors real-world decisions like braking versus swerving.
Some research suggests fast-paced action games can modestly improve choice reaction time and decision speed, likely due to repeated practice making rapid stimulus discrimination more automatic.
Yes, because choice reaction time requires an extra decision-making step, it tends to be more sensitive to fatigue, distraction, and cognitive load than simple reaction time.
Choice reaction time is typically 50-100 milliseconds slower than simple reaction time, reflecting the additional processing needed to identify which stimulus appeared before responding.
With practice, the decision-making component can become faster and more automatic, which can shrink but rarely eliminates the natural gap between simple and choice reaction time.
If the difference exceeds 100ms, stimulus discrimination or response selection may be your bottleneck rather than neural conduction speed, suggesting decision-making overhead rather than raw detection is limiting your score.