Name: ______Date:______

STIMULUS

RESPONSE PERFORMANCE LAB

PART 1

Goal

Determine if the reaction time of a reflex varies between one hand and the other hand.

1.What are the independent variables in this lab?

2.What is the dependent variable in this lab?

Hypothesis

I think that
because

Materials

•30-cm ruler

Procedure
1.Assign a task to each team member:
–Test subject: Person who stands upright.
–Experimenter: Person who holds the ruler.
2.The test subject spreads the thumb and the index finger of the right hand 1 cm apart.
3.The experimenter holds the ruler vertically with the 0 mark at the bottom just above the test subject’s right hand.
4.At an agreed signal, the experimenter drops the ruler.
5.The test subject catches the ruler between the thumb and the index finger as quickly
as possible.
6.Practise two or three times, then record the measurement indicated on the ruler by the test subject’s index finger.
7.Take two or three measurements.
8.Calculate the average of the results.
9.Repeat steps 2 to 8 with the left hand.
10.Repeat steps 2 to 9 by reversing the roles of the team members.
11.Put away materials.

Results

Record your results in the table below. Give the table a title.

Title:

Test subject / Measurement indicated on ruler
Right hand / Left hand
1
2

Analysis of the results

1.Is the reaction time of the reflex the same for both hands? Explain your answer.

2.Explain variations and differences.

3.Are the results the same for each test subject?

4.What are the possible sources of error in this lab?

5.How could you improve the protocol for this lab?

Conclusion

1.Complete the following sentence:

Reaction time / between one hand and the other hand.

2.Was your hypothesis confirmed or not? Explain your answer.

Application

What are the advantages of having good reflexes?

PART 2

Purpose: To measure response speed by catching a ruler as fast as possible after visual, auditory and tactile stimuli have been practiced.

Materials: Meter stick

Rules:

-You will work with the person next to you.

-You must stay seated during this activity.

Procedure:

  1. Look at the table on the next page. That is where you will record your results.
  2. One person will be the holder (the one dropping the ruler) and the other one will be the catcher (the one catching the ruler).
  3. The holder will hold the ruler above the catcher’s hand. Make sure that the 0 line on the ruler is between the catcher’s fingers.
  4. The holder will drop the ruler without any warning and the catcher must catch it as soon as possible after it has been released. Record the number on your ruler where you caught it.
  5. Repeat it 4 more times.
  6. Repeat 4 and 5, but this time the catcher will have his/her eyes closed and the holder will say “GO” to the catcher to warn him of the moment he/she will drop it.
  7. Repeat 4 and 5, but this time the catcher will have his/her eyes closed and the holder will touch the catcher’s hand to warn him of the moment he/she will drop it.
  8. Switch places with your partner, so that you both get to test it.

YOUR RESULTS

Signal / 1st Try / 2nd Try / 3rd Try / 4th Try / 5th Try / Average
Visual cue (eyes open)
Auditory cue (Sound: “GO”)
Tactile cue: (Touch)

Questions:

  1. In theory, which one of the tests (visual , auditory or tactile) should you be the fastest? Explain why.

❏Visual

❏Auditory

❏Tactile

______

  1. Which one of the tests (visual, auditory or tactile) did you perform the best? Where were your results the fastest? Why do you think those were your results?

❏Visual

❏Auditory

❏Tactile

______

  1. Which one of the tests (visual, auditory or tactile) did you perform the worst? Where were your results the slowest? Why do you think those were your results?

❏Visual

❏Auditory

❏Tactile

______

  1. How did your response speed change with practice?

______

  1. Number and draw the pathway of the information (1. Sensory receptor → 2. sensory nerve → 3. Brain → 4. motor nerve → 5. Part of the body that reacted to the stimulus)

Visual Cue (Eyes open): Auditory cue (Eyes closed, voice cue):

Tactile cue ( Eyes closed, touch cue)