Multiple-choice reaction time. Slot lights up - press the matching key. Tests S-R mapping speed.
Choice RT separates raw neural speed from stimulus-response mapping speed.
Hick's Law: RT increases linearly with the log of choices. 4-choice is ~150ms slower than 1-choice.
Practice automates the mapping - eventually the response feels involuntary.
Combined with simple RT, the two give a fuller speed profile.
Hick (1952) demonstrated the log-relationship now called Hick's Law.
Choice RT correlates more strongly with general intelligence than simple RT (r ≈ 0.4).
It captures how fast you can pick the right response, not just notice a signal.
This task isolates stimulus-response mapping: the time to register which slot lit, match it to its assigned key, and select that action over competing ones. Your score blends perceptual encoding, response selection, and motor execution. Because every trial forces a choice among alternatives, it indexes decision speed rather than raw alertness.
Unlike simple reaction time, where one signal maps to one key and no decision is needed, this adds a discrimination and selection stage. The gap between your simple and choice times estimates pure decision cost. Real-world analogues include sorting incoming items by category or steering toward the correct lane among several.
Build a fixed map first, then add alternatives once it feels automatic.
Start with two slots so each key becomes overlearned, then progress to four and beyond as accuracy holds above roughly nine in ten. Focus on keeping your fingers resting on their home keys and your eyes centred between slots, so no single position is favoured. Level up only when your times stop falling at the current count.
The common mistake is anticipating: pre-pressing a key on a hunch shaves milliseconds on lucky trials but produces wrong responses and inconsistent timing. Treat every error as costlier than a slow correct trial. Also resist tensing your whole hand; let only the selected finger move, since whole-hand readiness slows the eventual choice.
Read your own trend across sessions, not a single fast trial.
Your headline metric is mean correct reaction time, ideally paired with accuracy and the spread of your trials. Choice times naturally exceed simple ones and climb roughly with the logarithm of the slot count, so compare like with like. Strong performance shows steady, tight timings with few errors; a wide spread signals lapses even when your average looks good.
Reaction time is highly state-dependent: fatigue, caffeine, time of day, and even keyboard latency shift it by tens of milliseconds. A fast score does not certify broad processing speed or intelligence, and a slow one on a tired evening is not your ceiling. Watch direction over weeks rather than fixating on any one number.