Required Practical - Human Reaction Times

• If the reaction time is reduced this means it takes less time to react.
  • So, a reduction in the reaction time does NOT mean that someone is reacting more slowly, it means they are reacting more quickly.

• Caffeine and exercise are factors that could affect human reaction time
• Their effect can be tested by dropping and catching a ruler.

The steps in the practical procedure are:

1. Hold a ruler vertically from one end. The test subject should have their thumb and finger either side of the ruler at the 0cm mark.
2. Drop the ruler. The subject should try to catch it between their thumb and forefinger as fast as possible.
3. Note down the distance from the 0cm mark that the ruler travels before the subject catches it.
4. Use a table to convert this distance into a reaction time.
5. Repeat the experiment on a subject who has just had a coffee, or who has just done exercise.
6. Compare reaction times.

• The independent variable is whether or not the subject has had caffeine or exercised.
• The dependent variable is the subject’s reaction time.