What alcohol does to reaction time
What alcohol does to reaction time
260 ms–500 ms
Reaction — a decision, via the brain
Alcohol slows choice reaction considerably more than simple reaction, and it degrades error rates before it degrades speed — people become willing to respond when they should have withheld. That ordering is why impairment is visible in driving behaviour well before it is visible in a reaction test, and why the "I react fine" self-assessment is unreliable in exactly the direction that causes harm.
The numbers
- Typical
- 320 ms
- Range
- 260 ms to 500 ms
- What it is
- Reaction — a decision, via the brain
- What is measured
- Simple and choice reaction at blood alcohol concentrations around the common legal driving limits.
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
How it varies between people
| What | Typical | Range | Kind |
|---|---|---|---|
| How reaction time changes with age | 250 ms | 190 ms–400 ms | Reaction |
| What sleep loss does to reaction time | 300 ms | 250 ms–600 ms | Reaction |
Common questions
- How long is what alcohol does to reaction time?
- Typically 320 ms, with a real range of 260 ms to 500 ms. Simple and choice reaction at blood alcohol concentrations around the common legal driving limits.
- 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
- How reaction time changes with age 250 ms
- What sleep loss does to reaction time 300 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
- Typical range compiled from manufacturer specifications — At One Place