Choose, then react.
An arrow points left or right: press that side. A choice reaction test in your browser, and why deciding makes every reaction slower.
By Suraj Kumar3 min read
Simple reaction time is pressing when something happens. Choice reaction time is pressing the right thing when something happens, and it is always slower, because you must decide first.
Left or right.
After a wait you cannot guess, an arrow appears pointing left or right. Press the arrow key on that side, or tap that half of the box. A wrong side is counted and the try is taken again, so guessing never pays.
Why deciding takes time.
Hick's law, from the 1950s, says the time to choose grows with the number of choices. Even with two, the brain must tell which arrow it saw before the hand moves, so choice times are well over simple ones.
Compare with your simple reaction.
Take the colour test too. The gap between the two is roughly how long the decision takes you.
Further reading
Topics: choice reaction time test · choice reaction time · decision reaction test · hick's law · two choice reaction · reaction and decision speed
A little less theory. A little more doing.
Try it on your own terms, with a free browser tool.
Try the tool