Sensory Showdown: Reaction Time Lab
Names:
Period:
Background Information:
Reflexes are designed to protect you. Things like blinking your eye, the size of your pupil changing
when you step into a bright room, or pulling your hand back from a hot surface are all reflex actions. Reflexes
don’t require higher brain activity. If you touch a hot surface, you will actually pull your hand back before your
brain recognizes the heat.
Reactions require higher brain function. Putting your foot on the brake of the car when the car in front of
you slows or comes to a stop is an example of a reaction. You must first see the leading car’s brake lights; that
information must be processed by your brain and a signal must be sent to the muscles of your back and legs.
The signal not only tells you to step on the brake, but how hard to step on the brake.
Scientific Question: Who has a faster reaction males or females?
1. Hypothesis: If the brain responds to visual stimuli by sending messages to the hand to grasp the ruler
then (males/females ) will react (faster) because__________________________________________
_______________________________________________________________________________________.
2. Materials List: a) Ruler b) Pencil c) Lab report document
3. Procedure: working in groups of 3
Draw ruler here with lab set up
Job 1-drop ruler by holding at top with thumb and
pointer finger
Job 2-catch ruler with thumb and pointer finger
Job 3-record data
Scientist-choose best catch out of 3
4. Data Collection: Group Data
Student Name
Gender (M/F)
Reaction (mm)
1
2
3
Best CatchWhen finished write your data on the Class Data chart on the board
5. Class Data:
Male Name
Ruler mm
Female Name
Ruler mm
÷
Number of Males:
________
Sum of all male’s
measurements:
___________
Number of
Females:
_________
Average time of
Average time of
Males
Females
To find the average--divide the sum by the number of males
Example: 201 seconds ÷ 15 males=13.4 seconds
Sum of all female’s
measurement: ___________
5. Conclusion Questions:
1. What does your data tell you about reaction time between males and females?
When looking at the group data I notice that
________________________________________________________________________________________________.
2. a What is the difference between the male and female’s averages? ________________________________
2 b. Draw how big that is here:
2c. Do you think it’s a significant difference? (does it really matter?)
Yes because _______________________ or No because ___________________________
2 d. Do you accept or reject you hypothesis? Why?
I accept/reject my hypothesis because ___________________________________________________
3. Why did we find the average of the class’s measurement and not the sum? ______________________
_____________________________________________________________________________________
4a. If you continued to repeat the test for visual stimuli, do you think your reaction time would get faster? Why
or why not?
If I repeated the test for visual stimuli, my reaction time would __________________________because
________________________________________________________________________________________________.
5. Draw the path of sensory input from the visual stimuli (seeing the ruler) as it led to your reaction (grabbing
the ruler).
5. . Can you determine from our test whether males or females have a faster reaction time? 6. Would your
results hold true for all of Los Angeles? 7 All of the United States? Use evidence from the reading to justify
your claims. See below:
5. Claim: After conducting the reaction time lab I believe that (males / females / neither) have the fastest reaction time.
Evidence: This is true or not true because according to article _______________________________ paragraph _____
says ________________________________________________________________ so _________________________
______________________________________________________________________________________________.
.
6.Claim: This is true/not true for all of Los Angeles because (I think)_______________________________________…
Evidence: :This is true or not true because according to article _______________________________ paragraph
_______ says ________________________________________________________________ so
_______________________________________________________________________________________________.
7. Claim: This is true/not true for all of the United States because ___________________________________________
_______________________________________________________________________________________________.
Evidence: (be sure to include the title and paragraph number)
This is true or not true because according to article _______________________________ paragraph _______ says
________________________________________________________________ so __________________________
_________________________________________________________________________________________.
Background information adapted from the Exploratorium reaction time lab http://ed.fnal.gov/arise/guides/bio/8-Body-Systems/8c1NervousReactionTimeLabII.pdf