Choice reaction time
Choice reaction time
300 ms–500 ms
Reaction — a decision, via the brain
Adding a decision costs roughly 100 to 150 milliseconds over simple reaction, and the cost grows with the number of alternatives in a way that is close to logarithmic — Hick's law, which says reaction time rises with the base-2 logarithm of the number of choices. That logarithm is why a menu of eight items is not four times slower than a menu of two, and it is one of the few laboratory findings that transfers cleanly into interface design.
The numbers
- Typical
- 380 ms
- Range
- 300 ms to 500 ms
- What it is
- Reaction — a decision, via the brain
- What is measured
- Two or more stimuli, each with its own response. Press left for a red light, right for a green one.
Why this is a reaction
A reaction is a decision: signal in, processing, movement out. The floor for a human is around 150 milliseconds, and anything measured below about 100 ms is anticipation rather than response.
Where it sits against everything else
Reflexes at the top, reactions in the middle, design values off the end of the scale.
Vestibulo-ocular reflex — Reflex 10 ms
Knee-jerk (patellar) reflex — Reflex 22 ms
Latency added by your screen and mouse — Physical limit 35 ms
Blink reflex — Reflex 40 ms
Withdrawal reflex — Reflex 90 ms
Time a jab takes to land — Physical limit 110 ms
Sprint start reaction — Reaction 140 ms
Simple tactile reaction time — Reaction 155 ms
Simple auditory reaction time — Reaction 170 ms
Professional gamer reaction time — Reaction 190 ms
Formula One start reaction — Reaction 200 ms
Simple visual reaction time — Reaction 250 ms
How reaction time changes with age — Reaction 250 ms
What sleep loss does to reaction time — Reaction 300 ms
What alcohol does to reaction time — Reaction 320 ms
Recognition reaction time — Reaction 340 ms
Choice reaction time — Reaction 380 ms
Time to hit a 95 mph fastball — Physical limit 400 ms
Time a goalkeeper has on a penalty — Physical limit 450 ms
Time to play a 90 mph delivery — Physical limit 500 ms
Driver reaction to an expected event — Reaction 850 ms
The basic senses
| What | Typical | Range | Kind |
|---|---|---|---|
| Simple tactile reaction time | 155 ms | 130 ms–190 ms | Reaction |
| Simple auditory reaction time | 170 ms | 140 ms–200 ms | Reaction |
| Simple visual reaction time | 250 ms | 200 ms–300 ms | Reaction |
| Recognition reaction time | 340 ms | 280 ms–450 ms | Reaction |
Common questions
- How long is choice reaction time?
- Typically 380 ms, with a real range of 300 ms to 500 ms. Two or more stimuli, each with its own response. Press left for a red light, right for a green one.
- Is that a reflex or a reaction?
- Reaction — a decision, via the brain. A reaction is a decision: signal in, processing, movement out. The floor for a human is around 150 milliseconds, and anything measured below about 100 ms is anticipation rather than response.
Related pages
- Simple tactile reaction time 155 ms
- Simple auditory reaction time 170 ms
- Simple visual reaction time 250 ms
- Recognition reaction time 340 ms
- A reflex is not a reaction Why one is 20 ms and the other 250
- Stopping distance at every speed Reaction distance plus braking distance, computed
- Measure your own reaction time Five attempts, median reported
Sources
- Response Times: Their Role in Inferring Elementary Mental Organization — R. Duncan Luce, Oxford University Press, 1986