Download Stimulus Response Time Lab

Anatomy & Physiology
Ms. Buchalski
Name ___________________________________________
Date ______________
The Nervous System: Stimulus Response Time Lab Activity
Introduction: The human nervous system is composed of the brain and spinal cord (Central Nervous
System, CNS) and the nerves which branch out from the CNS, the Peripheral Nervous System (PNS).
Sensory neurons of the PNS carry information to the CNS. Signals from the brain are carried to motor
neurons (PNS), which carry out responses by muscles.
In this lab, you will be comparing the rate at which sensory neurons, working through the brain, can elicit
responses via motor neurons.
Purpose: To identify differences in the nervous system based on reaction response time
Materials:
 Meter stick
 Blindfold
 Partner
Procedure:
1. One person in the group will place his/her arm on a flat surface, such as a desk top.
The hand should extend over the edge of the desk.
2. The partner will hold the meter stick so that the end of the stick is between the thumb and
forefinger.
There should be space so that the meter stick can move between the fingers.
3. The person holding the meter stick will drop it without warning and the person with his/her arm
on the desk will grab the stick as quickly as possible. This will be done five times for each test
situation.
4. The person releasing the stick will record the point on the meter stick that the test subject grabs.
This number in centimeters is then recorded in the observation chart.
5. There are three test situations. The first is visual. The test subject will watch and react as soon as
the stick is released. The second test is auditory. The test subject is blindfolded and will respond
when the tester says now as the meter stick is released. The third is tactile. The test subject is still
blindfolded, but this time the tester will touch the person when the stick is released.
Observations:
Stimulus
Trial 1
Trial 2
Trial 3
Trial 4
Trial 5
Visual
Auditory
Tactile
Graphing: Upon completion, graph your data on the graph paper provided to you. You should have 3
lines on your graph. Be sure to include a key, title, and labels.
Anatomy & Physiology
Ms. Buchalski
Name ___________________________________________
Date ______________
Conclusion:
1. Which of the 3 scenarios allowed for the fastest response time? Offer an explanation as to why this
is so. Were both partners fastest for this scenario? Why might there be a difference?
2. Explain how your body is able to obtain information, process it, and then respond using the
correct terms. Use your book or the internet as a guide.